PLACE THESE INSTRUCTIONS ADJACENT TO HEATER AND NOTIFY OWNER TO KEEP FOR FUTURE REFERENCE.
KEEP THIS MANUAL IN THE POCKET ON HEATER FOR FUTURE REFERENCE WHENEVER MAINTENANCE ADJUSTMENT OR SERVICE IS
REQUIRED.
PRINTED 0625 100350709_2000594666A
Instruction Manual
HIGH-EFFICIENCY COMMERCIAL GAS WATER HEATERS
LOW LEAD
CONTENT
LISTED
WARNING: If the information in these
instructions is not followed exactly, a fire
or explosion may result causing property
damage, personal injury or death.
Do not store or use gasoline or other
flammable vapors and liquids in the
vicinity of this or any other appliance.
WHAT TO DO IF YOU SMELL GAS:
Do not try to light any appliance.
Do not touch any electrical switch; do
not use any phone in your building.
Immediately call your gas supplier
from a neighbor’s phone. Follow the
gas supplier’s instructions.
If you cannot reach your gas supplier,
call the fire department.
Installation and service must be
performed by a qualified installer,
service agency or the gas supplier.
•
•
•
•
Thank you for buying this energy ecient water heater. We
appreciate your condence in our products.
MODELS FLEX 60G/100G/119G
SERIES 400-401-450-451
INSTALLATION - OPERATION - SERVICE - MAINTENANCE
Failure to follow these instrucons and safety
messages could result in death or serious injury.
Read and understand this instrucon manual and the
safety messages herein before installing, operang or
servicing this water heater.
This manual must remain with the water heater.
⚠
WARNING
Safety Hazard
For Your Safety
AN ODORANT IS ADDED TO THE GAS USED
BY THIS WATER HEATER.
2 • High-Eciency Commercial Gas Water Heaters
CONTENTS
APPROVALS ............................................ ......................................................... 3
GENERAL SAFETY INFORMATION .................................................................. 3
Do Not Operate if damaged ...................................... ..................... ..3
Limiting the Risk of Scalding ............................................................3
Grounding Instructions ................................................... ................. 3
Hydrogen Gas Flammable ... ............................................... ..............3
Important Definitions ......................................................................4
Hazard Messages .......................................................................... ... 4
INTRODUCTION .............................................................................................. 7
Abbreviations Used .........................................................................7
Qualifications ..................................................................................7
ICOMM™ .........................................................................................7
Building Management System .........................................................7
Leak Detection ................................................................................7
AUTOMATIC WATER Shut-off Valve ..................................................7
Preparing for the Installation ...........................................................7
FEATURES AND COMPONENTS ...................................................................... 9
Basic Operation ...............................................................................9
Modulation ............................................... ..... ..... ...... ..... ...... ..... ..... ..9
Gas Valve ......................................................................................... 9
Blower/Burner Assembly Detail ......................................... ..... ...... ...9
Top View Components .......................... .........................................10
Side View Components ................... ............................................... 13
Recovery and Storage Capacities ................................................... 15
INSTALLATION CONSIDERATIONS ................................... ............................. 16
Rough In Dimensions ..................................................................... 16
Locating the Water Heater ............................................................ 17
Optional Terminations ................................................................... 18
Hard Water .................................................................................... 18
Circulation Pumps .........................................................................18
Insulation Blankets ........................................................................ 18
INSTALLATION REQUIREMENTS................................................................... 20
Gas Supply Systems .......................................................................20
Supply Gas Regulator ................................................... ........ ........ .. 20
Power Supply ................. ........ ........ ........ ........ ........ ......... ........ ....... 20
Mixing Valves.................................................................................21
Dish-washing Machines ................................................................. 21
Closed Water Systems ...................................................................21
Thermal Expansion ........................................................................ 21
Temperature-Pressure Relief Valve ................................................ 22
Condensate Drain .......................................................................... 23
Combustible Material Storage .......................................................23
Contaminated Air ..........................................................................24
Air Requirements ........................................................................... 24
Fresh Air Openings For Confined Spaces .......................................25
Massachusetts Installation Requirements .....................................27
VENTING INSTALLATION .............................................................................. 28
General Venting Information .........................................................28
Category IV Appliances ..................................................................28
General Venting Instructions ......................................................... 29
Venting Requirements ...................................................................29
Venting Installation Sequence .......................................................31
Power Vent Installation ................................................................. 31
Direct Vent Installation .................................................................. 32
Vertical Termination Installation ............................................. .......33
Horizontal Termination Installation ...............................................35
Polypropylene Installations ........................................................... 36
AL29-4C
®
Vent Installations............................................................36
Common Venting .................................................. .........................37
Concentric Termination Installation ...............................................37
Low Profile Vent Installation ................................... .......................41
Venting Arrangements ....................................................... ............43
Sidewall Termination Clearances ................................................... 45
INSTALLING THE WATER HEATER ................................................................. 47
Condensate Drain Installation .......................................................47
Leak Detection Module Installation ............................................... 47
Supply Gas Line Installation ........................................................... 48
Electrical Wiring ............................................................................50
Water Line Connections ................................................................51
START UP ......................................................... ............... ............... ............... . 53
Prior to Start up ................... ............................... ........................... 53
Filling The Water Heater ....................................... .........................53
Initial Start Up ............................................................................... 53
Gas Calibration ..............................................................................54
Start Up Conditions ....................................................................... 55
Operational Conditions .................................................................55
Start-Up Procedure ...................................................................... ..55
Lighting the Water Heater .............................................................56
Supply Gas Pressure Adjustment ...................................................58
Multiple Appliance Installations ....................................................58
Checking the Firing Rate ................................................................ 58
Turning Off the Gas Supply ............................................................ 58
High Altitude Installations .............................................................59
TEMPERATURE REGULATION ....................................................................... 60
High Temperature Limit Control ....................................................60
Thermostat Control .......................................................................60
Firing Rate Modulation .................................................................. 61
High Temperature Applications .....................................................61
CONTROL SYSTEM OPERATION ................................................................... 62
Limiting the Risk of Scalding .......................................................... 62
Wi-Fi ...................................... ........................................................62
Lockout Function ........................................................................... 62
Control System Overview ..............................................................62
Control System Navigation ............................................................62
User Settings & Control System Menus .........................................64
MAINTENANCE ............................................................................................. 76
Maintenance Schedule ..................................................................76
Draining and Flushing .................................................................... 76
Sediment Removal .................................. .............. ............... .......... 77
Lime Scale Removal .......................................................................77
Burner Flame Inspection ............................................................... 78
Anode Rod Maintenance ...............................................................78
Drain Valve and Access Panels ....................................................... 78
Temperature-Pressure Relief Valve Test ................... ......................79
Vent System Maintenance ............................................................. 79
TROUBLESHOOTING .......................................................................... ........... 80
Installation Checklist ..................................................................... 80
Sequence of Operation .......................................... ........................80
Operational Problems ............................... ........ ........ ........ ........ ..... 82
Replacement Parts ........................................................................83
Resetting Control System Lockouts ................................................83
Diagnostic Checks .............................................. ............................ 83
Fault and Alert Conditions ............................................................. 84
Checking for Leaks .............................................. ........................... 97
Checking Threaded Fittings ...........................................................97
DIAGRAMS .................................................................................................... 98
Wiring Diagrams ............................................................................ 98
Water Piping Diagrams ................................................................102
High-Eciency Commercial Gas Water Heaters • 3
APPROVALS
LOW LEAD
CONTENT
LISTED
Note:
ASME construcon is oponal on the 60G and 100G water
heaters covered in this manual.
GENERAL SAFETY INFORMATION
DO NOT OPERATE IF DAMAGED
DO NOT USE THIS APPLIANCE IF ANY PART HAS BEEN EXPOSED TO
FLOODING OR WATER DAMAGE.
Immediately call a qualied service
agency to inspect the appliance and to make a determinaon on what
steps should be taken next.
If the unit is exposed to the following, do not operate heater unl all
correcve steps have been made by a qualied service agency.
1. External re.
2. Damage.
3. Firing without water.
LIMITING THE RISK OF SCALDING
For a variety of reasons, water heaters can produce water that is much
hoer than its temperature seng. Take precauons to prevent this
higher temperature water from reaching the water xtures.
The temperature of the water in the water
heater can exceed the thermostat se�ng and
be hot enough to cause burns.
To reduce the risk of unusually hot water
reaching the fixtures in the house, install point
of use thermosta�c mixing valves at each point
of use.
⚠
WARNING
Burn Hazard
According to a naonal standard,
Performance Requirements for Water
Temperature Limiting Devices (ASSE 1070)
and many local plumbing codes,
the water heater’s gas control valve should not be used as the sole
means to regulate water temperature and avoid scalds.
A properly adjusted thermostac mixing valve at each point of use
allows you to set the tank temperature to a higher seng without
increasing risk of scalds. A higher temperature seng allows the
tank to provide much more hot water and can help provide proper
water temperatures for appliances such as dishwashers and washing
machines.
GROUNDING INSTRUCTIONS
This water heater must be grounded in accordance with the
National
Electrical Code
and/or local codes. These codes must be followed in
all cases. Failure to ground this water heater properly may also cause
errac control system operaon.
This water heater must be connected to a grounded metal, permanent
wiring system; or an equipment grounding conductor must be run with
the circuit conductors and connected to the equipment grounding
terminal or lead on the water heater.
HYDROGEN GAS FLAMMABLE
Hydrogen gas can be produced in a hot water system served by this
water heater that has not been used for a long period of me (generally
two weeks or more). Hydrogen gas is extremely ammable. To reduce
the risk of injury under these condions, it is recommended that a
hot water faucet served by this water heater be opened for several
minutes before using any electrical appliance connected to the hot
water system. If hydrogen is present there will probably be an unusual
sound such as air escaping through the pipe as the water begins to
ow. There should be no smoking or open ame near the faucet at
the me it is open.
Flammable hydrogen gases can form in water pipes.
The hydrogen can explode if it is exposed to flame and
can cause severe injury or death.
Keep all igni�on sources away from faucet when
turning on hot water.
⚠
WARNING
Explosion Hazard
Verify the power to the water heater is turned off before performing any service procedures. The Enable /Disable switch on front panel
disables the gas valve. Electrical supply must be turned off at circuit breaker serving water heater.
4 • High-Eciency Commercial Gas Water Heaters
IMPORTANT DEFINITIONS
Qualied Installer: A qualied installer must have ability equivalent to
a licensed tradesman in the elds of plumbing, air supply, venng and
gas supply, including a thorough understanding of the requirements
of the
National Fuel Gas Code, ANSI Z223.1/NFPA 54
as it relates to the
installaon of gas red water heaters. The qualied installer must
also be familiar with the design features and use of ammable vapor
ignion resistant water heaters and have a thorough understanding
of this Installaon and Operang manual.
Service Agency: A service agency also must have ability equivalent to
a licensed tradesman in the elds of plumbing, air supply, venng and
gas supply, including a thorough understanding of the requirements
of the
National Fuel Gas Code”, ANSI Z223.1/NFPA 54
as it relates to the
installaon of gas red water heaters. The service agency must also
have a thorough understanding of this Installaon and Operang
manual, and be able to perform repairs strictly in accordance with the
service guidelines provided by the manufacturer.
Gas Supplier: The Natural Gas or Propane Ulity or service who supplies
gas for ulizaon by the gas burning appliances within this applicaon.
The gas supplier typically has responsibility for the inspecon and
code approval of gas piping up to and including the Natural Gas meter
or Propane storage tank of a building. Many gas suppliers also oer
service and inspecon of appliances within the building.
HAZARD MESSAGES
The proper installaon, use, and servicing of this water heater is
extremely important to your safety and the safety of others.
Many safety-related messages and instrucons have been provided
in this manual and on your own water heater to warn you and others
of a potenal injury hazard. Read and obey all safety messages and
instrucons throughout this manual. It is very important that the
meaning of each safety message is understood by you and others who
install, use, or service this water heater.
This is the safety alert symbol. It is used
to alert you to potenal personal injury
hazards. Obey all safety messages that
follow this symbol to avoid possible
injury or death. Keep this manual near
the water heater.
DANGER DANGERᥕᥕ
DANGER
indicated an imminently
hazardous situaon which, if not
avoided, will result in injury or death.
WARNING WARNINGᥕᥕ
WARNING
indicates a potenally
hazardous situaon which if not avoided
could result in injury or death.
CAUTION CAUTIONᥕᥕ
CAUTION
indicates a potenally
hazardous situaon which, if not
avoided, could result in minor or
moderate injury.
CAUTION CAUTIONᕩᕩ
CAUTION
used without the safety alert
symbol indicates a potenally hazardous
situaon which, if not avoided could
result in property damage
All safety messages will generally tell you about the type of hazard,
what can happen if you do not follow the safety message, and how to
avoid the risk of injury.
CAUTION
Property Damage Hazard
Avoid water heater damage from pressure fluctua�ons
in closed water systems.
• Fill tank with water before operating.
• Install thermal expansion tank if necessary.
• Do not apply heat to cold water inlet.
• Contact qualified installer or service agency.
Failure to follow these instrucons and safety
messages could result in death or serious injury.
Read and understand this instrucon manual and the
safety messages herein before installing, operang or
servicing this water heater.
This manual must remain with the water heater.
⚠
WARNING
Safety Hazard
The temperature of the water in the water
heater can exceed the thermostat se�ng and
be hot enough to cause burns.
To reduce the risk of unusually hot water
reaching the fixtures in the house, install point
of use thermosta�c mixing valves at each point
of use.
⚠
WARNING
Burn Hazard
CAUTION
Property Damage Hazard
Over me, the tank and fings of the water heater
can begin to leak and cause water damage.
• Locate the water heater near an adequate drain
and in an area where water leakage from the
heater or connecons will not result in damage to
the area or the lower floors of the structure.
• Install the water heater in a drain pan.
⚠
DANGER
Burn Hazard
The discharge water from the temperature-pressure
relief valve is hot enough to cause burns.
Keep clear of the temperature-pressure relief valve
discharge outlet.
General Safety Informaon
High-Eciency Commercial Gas Water Heaters • 5
• Do not store or use gasoline or other flammable
vapors and liquids in the vicinity of this or any other
appliance.
• Avoid all ignition sources if you smell gas.
• Do not expose water heater controls to excessive gas
pressure.
• Use only the gas shown on the water heater rating
label.
• Maintain required clearances to combustibles.
• Keep ignition sources away from faucets after
extended periods of non-use.
Read instruc�on manual before installing, using or
servicing water heater.
⚠
WARNING
Fire or Explosion Hazard
• Do not obstruct water heater air intake
with insula�ng blanket.
• Gas and carbon monoxide detectors are
available.
• Install water heater in accordance with the
instruc�on manual.
Breathing carbon monoxide can cause brain damage or death. Always read
and understand instruc�on manual.
⚠
WARNING
Breathing Hazard - Carbon Monoxide Gas
Because of the increased risk from scalding, if you
set the water heater’s gas control knob higher than
120°F (49°C), install thermosta�c point-of-use
mixing valves at each point of use. Due to the
increased risk of scalding, do not set the tempera-
ture of the thermosta�c mixing valves above 120°F
(49°C).
⚠
DANGER
Burn Hazard
Normal opera�on of the water heater can cause
it to become sufficiently over-heated and/or
over-pressurized that it can explode, resul�ng in
property damage, sever injury, or death.
To avoid this hazard, you must install a properly-
sized temperature-pressure relief valve in opening
provided.
• The temperature-pressure relief valve must
comply with ANSI Z21.22-CSA 4.4 and ASME
code.
• Do not plug, block, or cap the discharge line.
⚠
WARNING
Explosion Hazard
Property Damage Hazard
While the water heater is in rou�ne opera�on, it can
release hot water from the temperature-pressure relief
valve discharge pipe in quan��es that could cause
damage to the surroundings.
Locate the water heater near an adequate drain and
in an area where water from the temperature-pres-
sure relief valve discharge pipe will not result in
damage to the area or the lower floors of the
structure.
⚠
CAUTION
• Install water heater in accordance with
the Instruction Manual and NFPA 54 or
CAN/CSA-B149.1.
• To avoid injury, combustion and ventilation air
must be taken from outdoors.
• Do not place chemical vapor emitting products
near water heater.
Breathing carbon monoxide can cause brain damage or death. Always
read and understand instruc�on manual.
⚠
WARNING
Breathing Hazard - Carbon Monoxide Gas
• Special considera�ons must be taken with
installa�ons above 10,100 (3,078 meters).
• Please contact an A. O. Smith qualified
service agent to obtain the proper setup
and instruc�ons before ligh�ng.
• Failure to implement the proper setup will
result in improper and inefficient opera�on
of the appliance, resul�ng in produc�on of
increased levels of carbon monoxide gas in
excess of the safe limits which could result
in serious personal injury or death.
Breathing carbon monoxide can cause brain damage or death. Always read
and understand instruc�on manual.
⚠
WARNING
Breathing Hazard - Carbon Monoxide Gas
• Do not use water heater with any gas other than
the gas shown on the rating label.
• Excessive gas pressure to gas valve can cause
serious injury or death.
• Turn off gas lines during installation.
• Contact a qualified installer or service agency for
installation and service.
⚠
WARNING
Fire and Explosion Hazard
6 • High-Eciency Commercial Gas Water Heaters
General Safety Informaon
• Use joint compound or thread sealer tape compatible
with propane gas.
• Leak test gas connections
before placing the water heater in operation.
• Disconnect gas piping at main gas shutoff valve before
leak testing.
• Install sediment trap in accordance
with NFPA 54 or CAN/CSA B149.1.
⚠
WARNING
Fire and Explosion Hazard
The temperature of the water in the water
heater can exceed the thermostat se�ng and
be hot enough to cause burns.
If you choose a higher temperature se�ng,
install thermosta�c mixing valves at each
point-of-use to help avoid scalding.
⚠
WARNING
Burn Hazard
Modifying the water heater to exceed the firing rate
on the ra�ng label can result in property damage,
personal injury or death.
• Under no circumstances should the input exceed
the rate shown on the water heater’s rating label.
• Over-firing could result in fire or explosion.
• Gas and carbon monoxide detectors are available.
⚠
WARNING
Fire and Explosion Hazard
• Under no circumstances should the input exceed
the rate shown on the water heater’s rating label.
• Overfiring could result in damage to the water
heater and sooting.
• Gas and carbon monoxide detectors are available.
Breathing carbon monoxide can cause brain damage or death. Always
read and understand instruc�on manual.
⚠
WARNING
Breathing Hazard - Carbon Monoxide Gas
Burn Hazard
• The combus�on chamber and burner
sleeve and housing become very hot
during opera�on.
• Do not reach into the burner housing or
combus�on chamber if the water heater is
s�ll hot.
• Allow the water heater to cool and always
use gloves when handling the main burner.
⚠
CAUTION
Servicing this water heater exposes you to
electrified components that can cause severe
injury or death if you touch them.
• Turn off power at the branch circuit breaker
serving the water heater before performing any
service.
• Label all wires prior to disconnecting when
performing service. Wiring errors can cause
improper and dangerous operation.
• Verify proper operation after servicing.
⚠
WARNING
Electrical Shock Hazard
Jumping out control circuits or components can
result in property damage, personal injury or death.
• Service should only be performed by a qualified
service technician using proper test equipment.
• Altering the water heater controls and/or wiring in
any way could result in permanent damage to the
controls or water heater and is not covered under
the limited warranty.
• Any bypass or alteration of the water heater
controls and/or wiring will result in voiding the
appl
iance warranty.
⚠
WARNING
Safety Hazard
⚠
CAUTION
Safety Hazard
Do not operate the water heater if it has been exposed to or exhibits
the following:
• Exposed to flooding or water damage
• External damage.
• Firing without water.
• Sooting.
Do not operate the water heater until all corrective steps
have been made by a qualified service technician.
• Overheated water can cause water tank explosion.
• A properly sized temperature and pressure relief
valve must be installed in the opening provided.
⚠
WARNING
Explosion Hazard
⚠
DANGER
Burn Hazard
The discharge water from the drain valve is hot enough
to cause burns.
Keep your hands clear of the drain valve discharge
outlet.
High-Eciency Commercial Gas Water Heaters • 7
INTRODUCTION
Thank You for purchasing this water heater. Properly installed and
maintained, it should give you years of trouble free service.
ABBREVIATIONS USED
Abbreviaons found in this Instrucon Manual include :
• ANSI - American Naonal Standards Instute
• ASME - American Society of Mechanical Engineers
• AHRI - Air Condioning, Heang and Refrigeraon Instute
• NEC - Naonal Electrical Code
• NFPA - Naonal Fire Protecon Associaon
• UL - Underwriters Laboratory
• CSA - Canadian Standards Associaon
QUALIFICATIONS
Qualified Installer or Service Agency
Installaon and service of this water heater requires ability equivalent
to that of a Qualied Agency (as dened by ANSI below) in the eld
involved. Installaon skills such as plumbing, air supply, venng, gas
supply and electrical supply are required in addion to electrical tesng
skills when performing service.
ANSI Z223.1 2006 Sec. 3.3.83:
“Qualied Agency” - “Any individual,
rm, corporaon or company that either in person or through a
representave is engaged in and is responsible for (a) the installaon,
tesng or replacement of gas piping or (b) the connecon, installaon,
testing, repair or servicing of appliances and equipment; that is
experienced in such work; that is familiar with all precauons required;
and that has complied with all the requirements of the authority
having jurisdicon.”
If you are not qualied (as dened by ANSI above) and licensed or
cered as required by the authority having jurisdicon to perform a
given task do not aempt to perform any of the procedures described
in this manual. If you do not understand the instrucons given in this
manual do not aempt to perform any procedures outlined in this
manual.
ICOMM™
This water heater comes equipped with the iCOMM™ remote
monitoring system. It allows users to monitor crical operaons and
diagnose issues remotely using the manufacturer’s water heater app
(available for IOS and Android).
The iCOMM™ system can automacally nofy selected personnel via
email and or cellular phone text messages if operaonal problems or
user dened Alert condions should occur. The system is expandable
to meet the needs of mulple heaters and groups of heaters.
To order or to nd out more about ICC devices, Technical Support.
To connect your water heater to iCOMM, download the A. O. Smith
app from the Apple App Store or Google Play store and follow the
instrucons for how to add your water heater.
BUILDING MANAGEMENT SYSTEM
This water heater is connecble to BACnet or Modbus compliant
Supervisory controls via the oponal ICC BMS Gateway. This allows
connecon of the water heater to local Building Management Systems
using Serial RS-485 (MS/TP) or IP connecons.
LEAK DETECTION
The water heaters covered in this manual are equipped with a leak
detecon device that connuously tests for the presence of water in
the immediate locaon of the water heater. If water is detected, it
generates an alarm.
AUTOMATIC WATER SHUT-OFF VALVE
The oponal Automac Water Shut o Valve and Valve Control Board
work in conjuncon with the TRC to help reduce the risk of further
water damage if a leak is detected by the leak detecon device.
PREPARING FOR THE INSTALLATION
1. Read the enre manual before aempng to install or operate the
water heater. Pay close aenon to the
General Safety Information
(page 3). If you don’t follow the safety rules, the water heater
may not operate safely. It could cause property damage, injury
and/or death.
This manual contains instrucons for the installaon, operaon,
and maintenance of the water heater. It also contains warnings
throughout the manual that you must read and be aware of. All
warnings and all instrucons are essenal to the proper operaon
of the water heater and your safety.
Detailed installaon diagrams are also found in this manual. These
diagrams will serve to provide the installer with a reference. It is
essenal that all venng, water piping, gas piping and wiring be
installed as shown.
Particular attention should be given to the installation of
thermometers at the locaons indicated in the piping diagrams as
these are necessary for checking the operaon of the water heater.
The principal components of the water heater are idened in
Features and Components
(page 9) in this manual. Use this
reference to locate and idenfy various components on the
water heater.
See
Installation Checklist
(page 80) and
Troubleshooting
(page
80). By using this checklist the user may be able to make
minor operaonal adjustments and avoid unnecessary service
calls. However, service and diagnosc procedures should only be
performed by a Qualied Service Agency.
Note:
Costs to correct installaon errors are not covered under
the limited warranty.
2. Be sure to turn o power when working on or near the electrical
system of the water heater. Never touch electrical components with
wet hands or when standing in water.
8 • High-Eciency Commercial Gas Water Heaters
Introducon
3. The installaon must conform to all instrucons contained in this
manual and the local code authority having jurisdicon. These shall
be carefully followed in all cases. Authories having jurisdicon
should be consulted before installaon begins if there are any
quesons regarding compliance with local, state or naonal codes.
In the absence of local codes, the installaon must comply with
the current edions of the
National Fuel Gas Code
,
ANSI Z223.1/NFPA
54
and the
National Electrical Code
,
NFPA 70
or
CAN/CSA-B149.1
,
the
Natural Gas and Propane Installation Code
and
CSA C22.1, the
Canadian Electrical Code
. All documents are available from the
Canadian Standards Associaon, 8501 East Pleasant Valley Road,
Cleveland, OH 44131. NFPA documents are also available from
the Naonal Fire Protecon Associaon, 1 Baerymarch Park,
Quincy, MA 02269.
4. If aer reading this manual you have any quesons or do not
understand any poron of the instrucons, call the toll free number
on the back cover of this manual for technical assistance. In order
to expedite your request, please have the full Model, Serial and
Series number of the water heater you are working with available
for the technician. This informaon is located on the water heater’s
rang label.
5. Carefully plan the placement of the water heater. Examine the
locaon to ensure that it complies with the requirements in
Rough
In Dimensions
(page 16) and
Locating the Water Heater
(page 17).
6. For installaon in California this water heater must be braced or
anchored to avoid falling or moving during an earthquake. See
instrucons for correct installaon procedures. Instrucons may
be obtained from California Oce of the State Architect, 1102 Q
Street, Suite 5100, Sacramento, CA 95811.
7. Massachuses Code requires this water heater to be installed in
accordance with
Massachusetts 248-CMR 2.00: State Plumbing Code
and
248-CMR 5
. See
Massachusetts Installation Requirements
(page
27).
High-Eciency Commercial Gas Water Heaters • 9
FEATURES AND COMPONENTS
BASIC OPERATION
The water heaters covered in this manual have a helical coil shaped
heat exchanger that is submerged in the storage tank. The water
heater’s Main Burner is a radial design burner, it is mounted on the
top and res downward through the heat exchanger. This is a forced
dra burner; hot burning gases are forced through the heat exchanger
under pressure and exit through the exhaust/vent connecon located
at the boom of the water heater. See
Figure 1
and
Figure 2
.
BLOWER
BURNER
ASSEMBLY
INTAKE AIR
(combustion air)
CONNECTION
MAIN
BURNER
(radial design)
HEAT
EXCHANGER
HELICAL
COIL
VENT (exhaust)
OUTLET
Figure 1. Operational Components
MODULATION
The water heaters covered by this manual are capable of adjusng their
ring rate. The combuson blower is controlled by the CSC. The TRC
and CSC monitor the water temperature in the tank and regulate the
ring rate to achieve the target temperature set-point. The ring rate
is dictated by the hot water draw, proximity to the tank temperature
set-point, and various other temperature limitaons.
GAS VALVE
This heater is equipped with a gas adapve system and motor driven
throle. It is controlled by the CSC in conjuncon with the TRC.
BLOWER/BURNER ASSEMBLY DETAIL
Intake Air Connection Pipe
Combustion
Blower
Assembly
Spark Igniter
Flame
Sensor
Main Burner
(radial design)
Burner Flange
Figure 2. Blower/Burner Assembly - 60 Gallon
Intake Air Connection Pipe
Combustion
Blower
Assembly
Spark Igniter
Flame
Sensor
Main Burner
(radial design)
Burner Flange
Figure 3. Blower Burner Assembly -100 Gallon
Intake Air Connection Pipe
Combustion
Blower
Assembly
Spark Igniter
Flame
Sensor
Main Burner
(radial design)
Burner Flange
Figure 4. Blower-Burner Assembly -119 Gallon
10 • High-Eciency Commercial Gas Water Heaters
Features and Components
Spark Igniter
The control system energizes the spark ignion control with 120 VAC
during the ignion period. The spark ignion control then sends a
high-voltage electrical current to the spark igniter which in turn ignites
the main burner air/gas mixture.
Flame Sensor
The control system also monitors the ame sensor to conrm a ame is
present at the Main Burner. If a ame is not veried during the ignion
trial period the control system will immediately deenergize the Gas
Valve. See
Sequence of Operation
(page 80).
TOP VIEW COMPONENTS
60 Gallon Top View
9
8
6
7
5
4
3
13
12
11
10
1
2
16
14
15
Figure 5. Top View, 60 Gallon
The Enable/Disable switch listed in this manual is NOT an “on/o”
switch and does not disconnect 120 volt power to the control boards
and other heater components.
1. Enable/Disable Switch. When in the “Disabled” posion the switch removes
electrical power from the gas valve so that water heang is disabled. The
UIM, TRC, CSC, and other electrical components will sll be energized and the
display will read “Water Heang Disabled”.
2. Temperature-Pressure Relief Valve (T & P Valve). See
Temperature-Pressure
Relief Valve
(page 22).
3. Control boards (TRC and CSC) enclosure. This enclosure houses the control
system’s TRC and CSC. The temperature regulaon control (TRC) and
combuson and safety control (CSC) regulate water temperature and control
all water heater funcons. See
Control System Operation
(page 62).
4. Combuson Blower Assembly. Includes Gas Valve and Venturi gas feed
system.
5. Spark Ignion Transformer. When energized, sends the electrical current to
the spark igniter.
6. 120 VAC juncon box. Incoming power supply, ground connecons, and other
eld-installed electrical connecons are made here. See
Power Supply
(page
20) and
Power Supply Connections
(page 50).
7. Supply gas line connecon. See the requirements for the supply gas line in
Table 4
(page 17)
and
Table 5
(page 17).
8. Water heater’s Gas Valve.
9. Intake air connecon - PVC. Refer to
Venting Installation
(page 28).
10. Blocked Intake Air switch. Normally closed contacts that open on fall in
pressure. This switch is used to ensure intake (combuson) air to the water
heater is not restricted. The control system monitors this switch and will
disable heang operaon if its contacts are open during a heang cycle.
11. Powered anode rod 31.5”. The water heaters covered in this manual are
equipped with a powered (non sacricial) anode rod. Protecve current
is fed by the control system to the tanium electrodes at the end of each
anode rod. This current ows through the water to the conducve surfaces
inside the storage tank which diminishes the corrosive eect of water when it
comes in contact with steel.
12. Main Temperature Probe. The water heater’s control system monitors this
probe to detect water temperature in the upper poron of the storage tank.
13. Water outlet connecon 1 1/2” NPT.
14. Flex Memory Module (FMM) under cover: The FMM board is located inside
the plasc display enclosure. The FMM board enables an FMM device to
communicate informaon with the heater.
DO NOT REMOVE OR DAMAGE THE
FMM BOARD
.
15. User Interface Module (UIM). The UIM includes the display circuit board and
the control system’s LCD Touch Display. Used to adjust various user sengs
and view operaonal informaon. See
Control System Operation
(page 62).
16. Vent connecon (exhaust/condensate elbow) - aluminum. Refer to
Venting
Installation
(page 28).
Features and Components
High-Eciency Commercial Gas Water Heaters • 11
100 Gallon Top View
9
8
6
7
5
4
14
13
12
11
1
3
17
15
16
2
10
Figure 6. Top View, 100 Gallon
The Enable/Disable switch listed in this manual is NOT an “on/o”
switch and does not disconnect 120 volt power to the control boards
and other heater components.
1. Water Heater’s Dual Voltage Enable/Disable Switch. When in the “Disabled”
posion the switch removes electrical power from the gas valve so that water
heang is disabled. The UIM, TRC, CSC, and other electrical components will
sll be energized and the display will read “Water Heang Disabled”.
2. Powered anode 13.78”. The water heaters covered in this manual are
equipped with powered (non sacricial) anode rods. Protecve current is fed
by the control system to the tanium electrodes at the end of each anode
rod. This current ows through the water to the conducve surfaces inside
the storage tank which diminishes the corrosive eect of water when it
comes in contact with steel.
3. Temperature-Pressure Relief Valve (T & P Valve). See
Temperature-Pressure
Relief Valve
(page 22).
4. Control boards (TRC and CSC) enclosure. This enclosure houses the control
system’s TRC and CSC. The temperature regulaon control (TRC) and
combuson and safety control (CSC) regulate water temperature and control
all water heater funcons. See
Control System Operation
(page 62).
5. Spark Ignion Transformer. When energized, sends the electrical current to
the spark igniter.
6. 120 VAC juncon box. Incoming power supply, ground connecons, and other
eld-installed electrical connecons are made here. See
Power Supply
(page
20) and
Power Supply Connections
(page 50).
7. Supply gas line connecon. See the requirements for the supply gas line in
Table 4
(page 17)
and
Table 5
(page 17).
8. Water heater’s Gas Valve.
9. Intake air connecon - PVC. Refer to
Venting Installation
(page 28).
10. Combuson Blower Assembly. Includes Gas Valve and Venturi gas feed
system.
11. Blocked Intake Air switch. Normally closed contacts that open on fall in
pressure. This switch is used to ensure intake (combuson) air to the water
heater is not restricted. The control system monitors this switch and will
disable heang operaon if its contacts are open during a heang cycle.
12. Powered anode 48”.
13. Main Temperature Probe. The water heater’s control system monitors this
probe to detect water temperature in the upper poron of the storage tank.
14. Water outlet connecon 1 1/2” NPT.
15. Flex Memory Module (FMM) under cover: The FMM board is located inside
the plasc display enclosure. The FMM board enables an FMM device to
communicate informaon with the heater.
DO NOT REMOVE OR DAMAGE THE
FMM BOARD
.
16. User Interface Module (UIM). The UIM includes the display circuit board and
the control system’s LCD Touch Display. Used to adjust various user sengs
and view operaonal informaon. See
Control System Operation
(page 62).
17. Vent connecon (exhaust/condensate elbow) - aluminum. Refer to
Venting
Installation
(page 28).
12 • High-Eciency Commercial Gas Water Heaters
Features and Components
13
11
7
6
5
4
17
16
15
14
1
2
18
3
20
10
12
19
8
9
Figure 7. Top View, 119 Gallon
The Enable/Disable switch listed in this manual is NOT an “on/o”
switch and does not disconnect 120 volt power to the control boards
and other heater components.
1. Water Heater’s Dual Voltage Enable/Disable Switch. When in the “Disabled”
posion the switch removes electrical power from the gas valve so that water
heang is disabled. The UIM, TRC, CSC, and other electrical components will
sll be energized and the display will read “Water Heang Disabled”.
2. Temperature-Pressure Relief Valve (T & P Valve). See
Temperature-Pressure
Relief Valve
(page 22).
3. Powered anode rod 19.69”. The water heaters covered in this manual are
equipped with powered (non sacricial) anode rods. Protecve current is fed
by the control system to the tanium electrodes at the end of each anode
rod. This current ows through the water to the conducve surfaces inside
the storage tank which diminishes the corrosive eect of water when it
comes in contact with steel.
4. Control boards (TRC and CSC) enclosure. This enclosure houses the control
system’s TRC and CSC. The temperature regulaon control (TRC) and
combuson and safety control (CSC) regulate water temperature and control
all water heater funcons. See
Control System Operation
(page 62).
5. Combuson Blower Assembly. Includes Gas Valve and Venturi gas feed
system.
6. Spark Ignion Transformer. When energized, sends the electrical current to
the spark igniter.
7. 120 VAC juncon box. Incoming power supply, ground connecons, and other
eld-installed electrical connecons are made here. See
Power Supply
(page
20) and
Power Supply Connections
(page 50).
8. Intake air connecon - PVC. Refer to
Venting Installation
(page 28).
9. Supply gas line connecon. See the requirements for the supply gas line in
Table 4
(page 17)
and
Table 5
(page 17).
10. Powered anode, shielded,.118 dia x 31.5. Approximate locaon (not visible.)
11. CPAM Power Supply: Provides power to the CPAM.
12. Water heater’s Gas Valve.
13. CPAM (Powered Anode Module): Axillary control for the operaon of
powered anodes.
14. Blocked Intake Air switch. Normally closed contacts that open on fall in
pressure. This switch is used to ensure intake (combuson) air to the water
heater is not restricted. The control system monitors this switch and will
disable heang operaon if its contacts are open during a heang cycle.
15. Powered anode 48”.
16. Main Temperature Probe, 1 of 2 temperature probes. The water heater’s
control system monitors this probe to detect water temperature in the upper
poron of the storage tank.
17. Water outlet connecon 1 1/2” NPT.
18. Flex Memory Module (FMM) under cover: The FMM board is located inside
the plasc display enclosure. The FMM board enables an FMM device to
communicate informaon with the heater.
DO NOT REMOVE OR DAMAGE THE
FFM BOARD
. *Not shown/visible.
19. User Interface Module (UIM). The UIM includes the display circuit board and
the control system’s LCD Touch Display. Used to adjust various user sengs
and view operaonal informaon. See
Control System Operation
(page 62).
20. Vent connecon (exhaust/condensate elbow) - aluminum. Refer to
Venting
Installation
(page 28).
Features and Components
High-Eciency Commercial Gas Water Heaters • 13
SIDE VIEW COMPONENTS
5
8
10
2
1
16
3
9
4
7
6
14
11
17
15
Figure 8. Left-Side Components
3
11
7
6
5
13
1
17
4
2
14
8
9
12
15
16
18
Figure 9. Right-Side Components
60 and 100 Gallon Models
1. Temperature-Pressure Relief Valve. See
Temperature-Pressure Relief Valve
(page 22).
2. User Interface Module (UIM). The UIM includes the display circuit board and
the control system’s LCD Touch Display. Used to adjust various user sengs
and view operaonal informaon. See
Control System Operation
(page 62).
3. Control boards enclosure. See
Figure 5, Figure 6,
and
Figure 7
(page 10) for
descripon.
4. Spark Ignion Transformer. When energized, sends the electrical current to
the spark igniter.
5. Combuson Blower.
6. Water heater Gas Valve.
7. Supply gas line connecon. See the requirements for the supply gas line in
Table 4
and
Table 5
(page 17).
8. Intake air connecon - PVC.
9. 120 VAC juncon box. Incoming power supply, ground connecons, and other
eld-installed electrical connecons are made here. See
Power Supply
(page
20) and
Power Supply Connections
(page 50) .
10. Water outlet - 1 1/2” NPT connecon.
11. Vent connecon (exhaust/condensate elbow) - Aluminum.
12. Water heater drain valve.
13. Leak Detecon Module. This feature senses the buildup of water in the
vicinity of the appliance. (Must be plugged in to operate the unit.)
14. Water inlet connecon - 1 1/2” NPT connecon.
15. Blocked Exhaust (vent) switch, under cover. Normally closed contacts that
open on a rise in pressure. This switch is used to ensure that the Exhaust
(vent) piping connected to the water heater is not restricted. The control
system monitors this switch and will disable heang operaon if its contacts
are open during a heang cycle
16. Clean-out access panel, covers water heater clean-out opening and ASME
plate where applicable.
17. Lower Temperature Probe, 1 of 2 temperature probes. The water heater’s
control system monitors this probe to detect water temperature in the lower
poron of the storage tank.
18. Recirculaon loop return connecon - 3/4” NPT.
19. Oponal BMS Module. This feature enables the heater to communicate with
a building management system. *Not shown/visible.
14 • High-Eciency Commercial Gas Water Heaters
Features and Components
1
3
4
15
14
8
13
12
11
10
8
7
6
9
2
5
18
16
Figure 10. Left Side
87
6
10
11
12
5
4
3
2
1
16
15
14
9
17
13
18
Figure 11. Right Side
119 Gallon Models
1. Control boards enclosure. See
Figure 5, Figure 6,
and
Figure 7
(page 10) for
descripon.
2. Water outlet - 1 1/2” NPT connecon.
3. User Interface Module (UIM). The UIM includes the display circuit board and
the control system’s LCD Touch Display. Used to adjust various user sengs
and view operaonal informaon. See
Control System Operation
(page 62).
4. Temperature-Pressure Relief Valve. See
Temperature-Pressure Relief Valve
(page 22).
5. Lower Temperature Probe, 1 of 2 temperature probes. The water heater’s
control system monitors this probe to detect water temperature in the lower
poron of the storage tank.
6. Clean-out access panel, covers water heater clean-out opening and ASME
plate where applicable.
7. Water heater drain valve.
8. Water inlet connecon - 1 1/2” NPT connecon.
9. Leak Detecon Module. This feature senses the buildup of water in the
vicinity of the appliance. (Must be plugged in to operate the unit.)
10. Blocked Exhaust (vent) switch. Normally closed contacts that open on a
rise in pressure. This switch is used to ensure that the Exhaust (vent) piping
connected to the water heater is not restricted. The control system monitors
this switch and will disable heang operaon if its contacts are open during a
heang cycle
11. Vent connecon (exhaust/condensate elbow) - Aluminum.
12. Recirculaon loop return connecon - 3/4” NPT.
13. Combuson Blower.
14. Water heater Gas Valve.
15. Supply gas line connecon. See the requirements for the supply gas line in
Table 4
and
Table 5
(page 17).
16. Intake air connecon - PVC.
17. 120 VAC juncon box. Incoming power supply, ground connecons, and other
eld-installed electrical connecons are made here. See
Power Supply
(page
20) and
Power Supply Connections
(page 50) .
18. Spark Ignion Transformer. When energized, sends the electrical current to
the spark igniter.
19. Oponal BMS Module. This feature enables the heater to communicate with
a building management system. *Not shown/visible.
Features and Components
High-Eciency Commercial Gas Water Heaters • 15
RECOVERY AND STORAGE CAPACITIES
Table 1. Storage Capacies
Model U.S. Gallons Liters
60 gallon 60 227
100 gallon 100 379
119 gallon 119 451
Table 2. Recovery Capacies
Model
Input °F
U.S. Gallons/hr & liters/hr at temperature rise indicated
30°F 40°F 50°F 60°F 70°F 80°F 90°F 100°F 110°F 120°F 130°F 140°F
Btu/hr kW °C 17°C 22°C 28°C 33°C 39°C 44°C 50°C 56°C 61°C 67°C 72°C 78°C
100 100,000 29
GPH 384 288 230 192 165 144 128 115 105 96 89 82
LPH 1453 1090 872 726 623 545 484 436 396 363 335 311
120 120,000 35
GPH 461 345 276 230 197 173 154 138 126 115 106 99
LPH 1743 1308 1046 872 747 654 581 523 475 436 402 374
150 150,000 44
GPH 576 432 345 288 247 216 192 173 157 144 133 123
LPH 2179 1634 1308 1090 963 817 726 654 594 545 503 467
199 199,900 58
GPH 768 576 461 384 329 294 288 256 230 209 192 177
LPH 2906 2179 1744 1453 1245 1112 1090 967 872 793 726 671
250 250,000 73
GPH 960 720 576 480 411 360 320 288 262 240 221 206
LPH 3632 2724 2179 1816 1557 1362 1211 1090 991 908 838 778
251 251,000 74
GPH 963 723 578 481 413 361 321 289 263 241 222 206
LPH 3647 2735 2188 1823 1563 1368 1214 1094 995 912 842 781
300 300,000 88
GPH 1152 864 691 576 494 432 384 345 314 288 266 247
LPH 4359 3269 2615 2179 1868 1635 1453 1307 1189 1090 1005 934
400 400,000 117
GPH 1535 1152 921 768 658 576 512 461 419 384 354 329
LPH 5812 4358 3487 2906 2491 2179 1937 1744 1585 1453 1341 1245
500 500,000 146
GPH 1919 1439 1152 960 823 720 640 576 523 480 443 411
LPH 7265 5448 4358 3632 3114 2724 2421 2179 1981 1816 1677 1557
Recovery capacies are based on 95% thermal eciency.
16 • High-Eciency Commercial Gas Water Heaters
INSTALLATION CONSIDERATIONS
ROUGH IN DIMENSIONS
GAS
INTAKE
CLEANOUT
T&P
DRAIN
EXHAUST
1 1/2" NPT
WATER
OUTLET
FRONT
18°
TOP
40°
45°
30°
22°
TOP VIEW
INTAKE
CLEANOUT
T&P
DRAIN
EXHAUST
1 1/2" NPT
WATER
OUTLET
FRONT
18°
TOP
44°
45°
30°
64°
64°
TOP VIEW
60 Gallon
100 Gallon
65°
GAS
SUPPLY GAS
CONNECTION
INTAKE AIR
CONNECTION
3 INCH PVC
WATER
OUTLET
HEIGHT
F
I
H
SUPPLY GAS
CONNECTION
INTAKE AIR
CONNECTION
3 INCH PVC
WATER
OUTLET
HEIGHT
F
I
H
FRONT
VENT
CONNECTION
3 INCH
(exhaust elbow)
T & P VALVE
CLEANOUT
3/4” NPT
DRAIN
3/4” NPT
RECIRCULATION
RETURN
1 1/2” NPT
WATER
INLET
LOWER
TEMPERATURE
PROBE
D
E
A
J
G
C
B
FRONT
VENT
CONNECTION
3 INCH
(exhaust elbow)
T & P VALVE
CLEANOUT
3/4” NPT
DRAIN
3/4” NPT
RECIRCULATION
RETURN
1 1/2” NPT
WATER
INLET
LOWER
TEMPERATURE
PROBE
D
E
A
J
G
C
B
GAS
INTAKE
CLEANOUT
T&P
DRAIN
EXHAUST
1 1/2" NPT
WATER
OUTLET
FRONT
18°
TOP
42°
45°
30°
15°
30°
119 GALLON
SUPPLY GAS
CONNECTION
INTAKE AIR
CONNECTION
4 INCH PVC
WATER
OUTLET
HEIGHT
F
I
H
FRONT
VENT
CONNECTION
3 INCH
(exhaust elbow)
T & P VALVE
CLEANOUT
3/4” NPT
DRAIN
3/4” NPT
RECIRCULATION
RETURN
1 1/2” NPT
WATER
INLET
LOWER
TEMPERATURE
PROBE
D
E
A
J
G
C
B
&
Figure 12. Rough-in Dimensions
Installaon Consideraons
High-Eciency Commercial Gas Water Heaters • 17
Model
(Gallon)
Table 3. Dimensions by Model
APPROX. SHIP
WEIGHT STD
APPROX. SHIP
WEIGHT ASME
A B C D E F G H I J
in (cm) in (cm) in (cm) in (cm) in (cm) in (cm) in (cm) in (cm) in (cm) in (cm) LBS (KG) LBS (KG)
60
55-1/2
(141)
35
(88.9)
27-3/4
(70.5)
6-5/16
(16)
3
(7.62)
42-1/4
(107.32)
11-1/4
(28.6)
48-1/2 (123.2)
53-1/2
(135.9)
18-1/4
(46.36)
460
(208)
490
(220)
100
76-1/2
(194.9)
56-3/8
(143.2)
27-3/4
(70.5)
6-5/16
(16)
3
(7.62)
64
(162.6)
11-1/4
(28.6)
70
(177.8)
75-1/2
(191.8)
18-1/4
(46.36)
523
(237)
553
(251)
119
75-3/4
(197.5)
52
(132)
33-1/8
(84.1)
4-3/4
(12.1)
4-3/4
(12.1)
63-1/8
(160.3)
12-3/4
(32.4)
69-1/4
(175.9)
74-1/2
(189.2)
23
(58.4)
855
(388)
855
(388)
These designs comply with the current edion of the
American National
Standard for Gas Fired Water Heaters, Volume III
,
ANSI Z21.10.3-CSA 4.3
.
The 100K-400K input water heaters are Automac Circulang Tank or
Automac Storage Water Heaters. The 500K-input water heater is an
Automac Circulang Tank or Automac Instantaneous water heater.
Table 4. Fuel Type/Connecon Size by Model
† MODEL SERIES NATURAL GAS PROPANE GAS
60 Gallon 400-401-450-451 3/4” NPT 3/4” NPT
100 Gallon 400-401-450-451 3/4” NPT 3/4” NPT
119 Gallon 400-401-450-451 1 1/4” NPT 1 1/4” NPT
† Depending on the installed equivalent length, and/or the number of appliances
connected, the supply gas line size may have to be increased beyond the minimum
required sizes. See
Gas Line Sizing
(page 48).
Table 4
shows connecons sizes only. Depending on the installed
equivalent length, and/or the number of appliances connected, the
supply gas line size may have to be increased beyond the minimum
required sizes. See
Gas Line Sizing
(page 48).
Table 5. Gas Pressure Requirement
Model
*Manifold Pressure Minimum Supply Pressure Maximum Supply Pressure
Natural Gas Propane Gas Natural Gas Propane Gas Natural Gas Propane Gas
60G 0” W. C. (0 kPa) 0” W. C. (0 kPa) 3.5” W .C. (0.87 kPa) 8.0” W. C. (1.99 kPa) 14” W. C. (3.49 kPa) 14” W. C. (3.49 kPa)
100G 0” W. C. (0 kPa) 0” W. C. (0 kPa) 3.5” W .C. (0.87 kPa) 8.0” W. C. (1.99 kPa) 14” W. C. (3.49 kPa) 14” W. C. (3.49 kPa)
119G 0” W. C. (0 kPa) 0” W. C. (0 kPa) 3.5” W .C. (0.87 kPa) 8.0” W. C. (1.99 kPa) 14” W. C. (3.49 kPa) 14” W. C. (3.49 kPa)
*
The manifold pressure is the factory setting and is not adjustable. A negative pressure will be seen with just the blower running without the Gas Control Valve open.
LOCATING THE WATER HEATER
Carefully choose a locaon for the new water heater. The placement is
a very important consideraon for the safety of the occupants in the
building and for the most economical use of the water heater.
CAUTION
Property Damage Hazard
Over me, the tank and fings of the water heater
can begin to leak and cause water damage.
• Locate the water heater near an adequate drain
and in an area where water leakage from the
heater or connecons will not result in damage to
the area or the lower floors of the structure.
• Install the water heater in a drain pan.
Whether replacing an exisng water heater or installing the water
heater in a new locaon observe the following crical points:
1. The water heater must be located indoors.
2. The water heater must not be located in an area where it will be
subject to freezing temperatures.
3. Locate the water heater so it is protected and not subject to physical
damage by a moving vehicle.
4. Locate the water heater on a level surface.
5. Locate the water heater near a oor drain. The water heater should
be located in an area where leakage of the tank or connecons will
not result in damage to the area adjacent to the water heater or
to lower oors of the structure. When such locaons cannot be
avoided, it is recommended that a metal drain pan, adequately
drained, be installed under the water heater.
6. Locate the water heater close to the point of major hot water usage.
7. Locate the water heater close to a 120 VAC power supply. See
Power
Supply
(page 20) for requirements.
8. Locate the water heater where an adequate supply of fresh air for
combuson and venlaon can be obtained. See
Air Requirements
(page 24).
9. Locate the water heater where the vent and intake-air piping,
when installed, will remain within the maximum equivalent lengths
allowed. See
Venting Requirements
(page 29).
10. Do not locate the water heater where noise (such as the Combuson
Blower) during normal operaon will be objeconable in adjacent
areas.
11. Do not locate the water heater where the subsequent installaon of
the vent (exhaust) or intake-air terminaons would be objeconable
due to noise at the terminaon(s). This includes locaons close to
or across from windows and doors. See
Venting Installation
(page
28) .
18 • High-Eciency Commercial Gas Water Heaters
Installaon Consideraons
• Do not store or use gasoline or other flammable
vapors and liquids in the vicinity of this or any other
appliance.
• Avoid all ignition sources if you smell gas.
• Do not expose water heater controls to excessive gas
pressure.
• Use only the gas shown on the water heater rating
label.
• Maintain required clearances to combustibles.
• Keep ignition sources away from faucets after
extended periods of non-use.
Read instruc�on manual before installing, using or
servicing water heater.
⚠
WARNING
Fire or Explosion Hazard
There is a risk in using fuel burning appliances such as gas water heaters
in rooms, garages or other areas where gasoline, other ammable
liquids or engine driven equipment or vehicles are stored, operated or
repaired. Flammable vapors are heavy and travel along the oor and
may be ignited by the water heater’s igniter or Main Burner ames
causing re or explosion.
Flammable items, pressurized containers or any other potenal re
hazardous arcles must never be placed on or adjacent to the water
heater.
Clearance to Combustible Materials
The water heaters covered in this manual are approved for installaon
on combustible flooring. The clearance to combustible and non
combusble construcon materials is 0 inches on the back and sides of
the water heater. These water heaters are also approved for installaon
in an alcove.
When the water heater is installed directly on carpeng, the water
heater shall be installed on a metal or wood panel extending beyond
the full width and depth of the water heater by at least 3 in (76.2
mm) in any direcon or, if the water heater is installed in an alcove or
closet, the enre oor shall be covered by the panel. The panel must
be strong enough to carry the weight of the heater when full of water.
Note:
Adequate clearance for servicing should be maintained on all
installaons. See
Service Clearance
below.
TOP VIEW
0
0
0
ALCOVE
FRONT VIEW
CLEARANCES TO COMBUSTIBLE
AND NON COMBUSTIBLE
CONSTRUCTION MATERIALS
WATER
HEATER
FRONT
TOP COVER
FRONT
Figure 13. Clearances
Service Clearance
A service clearance of 24 inches (61 cm) should be maintained from
serviceable parts such as the T&P valve, control system components,
gas valve, clean out opening, drain valve, the vent connecon (exhaust/
condensate elbow) and the condensate drain. Leave as much room
as possible above the water heater and near the exhaust elbow for
this reason.
Intake Air and Vent Pipe Clearances
The minimum clearance from combusble materials for the vent
(exhaust) and intake-air piping shall be 0 inches. Vent or intake-
air piping passing through a combusble wall or ceiling must be a
connuous run (no joints).
OPTIONAL TERMINATIONS
The water heaters covered by this manual can be installed in a
Direct Vent conguraon using oponal concentric or low prole
terminaons.
See
Low Profile Vent Installation
(page 41), and
Low Profile Vent
Installation
(page 41).
Concentric and low prole terminaons must be ordered separately.
Contact Technical Support for assistance in ordering the concentric
terminations or low profile vent terminations. See the contact
informaon label on the water heater.
HARD WATER
Where hard water condions exist, water soening or the threshold
type of water treatment is recommended. This will protect the
dishwashers, coee urns, water heaters, water piping and other
equipment.
See
Maintenance
(page 76) for sediment and lime scale removal
procedures.
CIRCULATION PUMPS
A circulang pump is used when a system requires a circulang loop or
there is a storage tank used in conjuncon with the water heater. The
tank is provided with a 3/4” NPT recirculaon loop return connecon.
See
Figure 8
through
Figure 11
(page 13)
for its locaon. See
Water
Piping Diagrams
(page 102) for the installaon locaon of circulang
pumps.
See (page 101) for electrical hookup informaon. Install in accordance
with the current edion of the
National Electrical Code
,
NFPA 70
or the
Canadian Electrical Code
,
CSA C22.1
.
Stainless Steel circulang pumps are recommended for use with
commercial water heaters.
See the circulang pump manufacturer’s instrucons for its operaon,
lubricaon and maintenance instrucons.
INSULATION BLANKETS
Insulaon blankets are available to the general public for external use
on gas water heaters but are not necessary with these products. The
Installaon Consideraons
High-Eciency Commercial Gas Water Heaters • 19
purpose of an insulaon blanket is to reduce the standby heat loss
encountered with storage tank heaters. The water heaters covered
by this manual meet or exceed the
Energy Policy Act
standards with
respect to insulaon and standby heat loss requirements, making an
insulaon blanket unnecessary.
• Do not obstruct water heater air intake
with insula�ng blanket.
• Gas and carbon monoxide detectors are
available.
• Install water heater in accordance with the
instruc�on manual.
Breathing carbon monoxide can cause brain damage or death. Always read
and understand instruc�on manual.
⚠
WARNING
Breathing Hazard - Carbon Monoxide Gas
Should you choose to apply an insulaon blanket to this heater, you
should follow these instrucons. See
Features and Components
(page
9) for identification of components mentioned below. Failure to
follow these instrucons can restrict the air ow required for proper
combuson, potenally resulng in re, asphyxiaon, serious personal
injury or death.
•
Do not
apply insulaon to the top of the water heater, as this will
interfere with safe operaon of the blower assembly.
•
Do not
cover the control system LCD on top of the water heater.
•
Do not
cover the Temperature-Pressure Relief Valve.
•
Do not
cover the instrucon manual. Keep it on the side of the
water heater or nearby for future reference.
•
Do
obtain new warning and instrucon labels from the
manufacturer for placement on the blanket directly over the
exisng labels.
•
Do
inspect the insulaon blanket frequently to make certain it
does not sag, thereby obstrucng combuson air ow.
20 • High-Eciency Commercial Gas Water Heaters
INSTALLATION REQUIREMENTS
GAS SUPPLY SYSTEMS
Low pressure building gas supply systems are dened as those systems
that cannot under any circumstances exceed 14” W.C. (1/2 PSI Gauge).
These systems do not require pressure regulaon. Measurements
should be taken to ensure that gas pressures are stable and fall within
the requirements stated on the water heater rang plate. Readings
should be taken with all gas burning equipment o (stac pressure)
and with all gas burning equipment running at maximum rate (dynamic
pressure). The gas supply pressure must be stable within 1.5” W.C.
from static to dynamic pressure to provide good performance.
Pressure drops that exceed 1.5” W.C. can cause rough starng, noisy
combuson or nuisance outages. Increases or spikes in stac pressure
during o cycles may cause failure to ignite or in severe cases damage
to appliance gas valves. If your low pressure system does NOT meet
these requirements, the installer is responsible for the correcons.
High Pressure building supply systems use pressures that exceed 14”
W.C. (1/2 PSI Gauge). These systems must use eld-supplied regulators
to lower the gas pressure to less than 14” W.C. (1/2 PSI Gauge). Water
heaters require gas regulators that are properly sized for the water
heater input and deliver the rang plate specied pressures. Gas
supply systems where pressure exceeds 5 PSI oen require mulple
regulators to achieve desired pressures. Systems in excess of 5 PSI
building pressure should be designed by gas delivery professionals
for best performance. Water heaters connected to gas supply systems
that exceed 14” W.C. (1/2 PSI Gauge) at any me must be equipped
with a gas supply regulator.
60/100/119 gallon model units require a minimum gas supply pressure
of 3.5” W.C. for natural gas and 8” W.C. for propane gas. The supply
pressure should never fall below 3.5” W.C. for natural gas and 8” W.C.
for propane gas.
The minimum supply pressure is measured while gas is flowing
(dynamic pressure). The supply pressure should never fall below the
minimums. The supply pressure should be measured with all gas red
appliances connected to the common main ring at full capacity. If the
supply pressure drops more than 1.5” W.C. as gas begins to ow to
the water heater, the supply gas system, including the gas line and/
or the gas regulator, might be restricted or undersized. See
Supply
Gas Regulator
(page 20), the requirements for the supply gas line
in
Table 4
(page 17)
and
Table 5
(page 17), and the instrucons in
Supply Gas Line Installation
(page 48). The gas valve on all models
has a maximum gas supply pressure limit of 14” W.C. The maximum
supply pressure is measured while gas is not owing (stac pressure).
SUPPLY GAS REGULATOR
1. The maximum allowable gas supply pressure for this water heater is
14.0” W. C. (3.49 kPa) for natural and propane gas. Install a posive
lock-up gas pressure regulator in the gas supply line if inlet gas
pressure can exceed these pressures at any me.
2. If a posive lock-up regulator is required follow these instrucons:
3. Posive lock-up gas pressure regulators must be rated at or above
the input Btu/hr rang of the water heater they supply.
4. Supply gas regulators shall have inlet and outlet connecons not
less than the minimum supply gas line size for the water heater they
supply. See
Table 17
(page 48) and
Table 18
(page 49).
5. Posive lock-up gas pressure regulator(s) should be installed no
closer than 3 feet (1 meter) and no farther than 8 feet (2.4 meters)
from the water heater’s inlet gas connecon.
6. Aer installing the posive lock-up gas pressure regulator(s) an
inial nominal supply pressure seng of 7.0” W.C. while the water
heater is operang is recommended and will generally provide
good water heater operaon. Some addional adjustment maybe
required later to maintain a steady gas supply pressure.
When installing mulple water heaters in the same gas supply system it
is recommended that individual posive lock-up gas pressure regulators
be installed at each unit.
Ensure that the gas line is properly supported to reduce the weight
on the gas train support.
POWER SUPPLY
The water heaters covered in this manual require a 120 VAC, 1Ø (single
phase), 60Hz, 15 amp power supply and must also be electrically
grounded in accordance with local codes or, in the absence of local
codes, with the
National Electrical Code
,
ANSI/NFPA 70
or the
Canadian
Electrical Code, CSA C22.1
.
Dedicated Power Wiring and Breakers
Dedicated power supply wires, neutral wires, ground wiring and
dedicated circuit breakers oen prevent electrical line noise and are
required when installing the water heater.
Note:
This water heater should not be connected to an electrical
supply with a Ground Fault Circuit Interrupter (GFCI) or Arc
Fault Circuit Interrupter (AFCI) with Integral GFCI protecon as
dened in
NFPA 70, CSA C22.1
and
UL 943
.
Power Fluctuations and Electrical Noise
The water heater’s control system requires a source of stable clean
electricity for proper operaon. Connecng the water heater to a
branch circuit that is subject to uctuaons in voltage level or electrical
line noise such as EMI (electro magnec interference) or RFI (radio
frequency interference) may cause errac control system operaon
and malfuncon.
A high quality power supply filter/suppressor are commercially
available and must be installed if the above condions exist.
Note:
Malfuncons caused by the power supply and the costs to install
power supply lters are not covered under the limited warranty.
Installaon Requirements
High-Eciency Commercial Gas Water Heaters • 21
MIXING VALVES
Because of the increased risk from scalding, if you
set the water heater’s gas control knob higher than
120°F (49°C), install thermosta�c point-of-use
mixing valves at each point of use. Due to the
increased risk of scalding, do not set the tempera-
ture of the thermosta�c mixing valves above 120°F
(49°C).
⚠
DANGER
Burn Hazard
Water heated to a temperature which will sasfy clothes washing, dish
washing, and other sanizing needs can scald and cause permanent
injury upon contact. Short repeated heang cycles caused by small hot
water uses can cause temperatures at the point of use to exceed the
water heater’s temperature seng by up to 20°F (11°C).
Some people are more likely to be permanently injured by hot water
than others. These include the elderly, children, the inrm and the
physically/mentally disabled.
Table 6
shows the approximate me-
to-burn relaonship for normal adult skin. If anyone using hot water
provided by the water heater being installed ts into one of these
groups or if there is a local code or state law requiring a certain water
temperature at the point of use, then special precauons must be
taken.
In addition to using the lowest possible temperature setting that satisfies
the demand of the application a means, such as a thermostatic point-of-
use mixing valve, for example, can be used at the hot water taps used
by these people to reduce the water temperature.
Check State and/or local codes for thermostac point-of-use mixing
valve requirements and installaon pracces.
Mixing valves are available at plumbing supply stores. Consult a
Qualied Installer or Service Agency. Follow mixing valve manufacturer’s
instrucons for installaon of the valves.
Table 6. Burn Time at Various Temperatures
Water Temperature
°F (°C)
Time for 1st Degree Burn
(Less Severe Burns)
Time for Permanent Burns
2nd & 3rd Degree
(Most Severe Burns)
110 (43) (Normal shower temp.)
116 (47) (Pain threshold)
116 (47) 35 minutes 45 minutes
122 (50) 1 minute 5 minutes
131 (55) 5 seconds 25 seconds
140 (60) 2 seconds 5 seconds
149 (65) 1 second 2 seconds
154 (68) Instantaneous 1 second
(U.S. Government Memorandum, C.P.S.C., Peter L. Armstrong, Sept. 15, 1978)
HOT WATER
OUTLET
TO TANK
INLET
CHECK
VALVE
MIXING
VALVE
COLD
WATER
INLET
TEMPERED WATER
OUTLET
12” TO 15”
(30-38 cm)
CHECK
VALVE
Figure 14. Mixing Valve
DISH-WASHING MACHINES
All dish-washing machines meeng the
National Sanitation Foundation
requirements are designed to operate with water ow pressures
between 15 and 25 pounds per square inch (103 kPa and 173 kPa).
Flow pressures above 25 pounds per square inch (173 kPa), or below
15 pounds per square inch (103 kPa), will result in improperly sanized
dishes. Where pressures are high, a water pressure reducing or ow
regulang control valve should be used in the 180°F (82°C) line to the
dish-washing machine and should be adjusted to deliver water pressure
between these limits.
The
National Sanitation Foundation
also recommends circulaon of 180°F
(82°C) water. The circulaon should be just enough to provide 180°F
(82°C) water at the point of take-o to the dish-washing machine.
Adjust ow by throling a full port ball valve installed in the circulang
line on the outlet side of the pump. Never throle ow on the sucon
side of a pump. See
Water Piping Diagrams
(page 102).
Note:
To comply with
NSF Standard 5
installaon requirements the
boom of the water heater must be sealed to the oor with
a silicone based sealant or elevated 6 inches above the oor.
CLOSED WATER SYSTEMS
Water supply systems may, because of code requirements or such
conditions as high line pressure, among others, have installed
devices such as pressure reducing valves, check valves, and back ow
preventers. Devices such as these cause the water system to be a
closed system.
THERMAL EXPANSION
As water is heated, it expands (thermal expansion). In a closed system
the volume of water will grow when it is heated. As the volume of water
grows there will be a corresponding increase in water pressure due
to thermal expansion. Thermal expansion can cause premature tank
failure (leakage). This type of failure is not covered under the limited
warranty. Thermal expansion can also cause intermient Temperature-
Pressure Relief Valve operaon: water discharged from the valve due
to excessive pressure build up. This condion is not covered under
the limited warranty. The Temperature-Pressure Relief Valve is not
intended for the constant relief of thermal expansion.
22 • High-Eciency Commercial Gas Water Heaters
Installaon Requirements
A properly sized and pressurized thermal expansion tank must be
installed on all closed systems to control the harmful eects of thermal
expansion. Contact a local plumbing service agency to have a thermal
expansion tank installed.
See
Water Line Connections
(page 51) and the
Water Piping Diagrams
(page 102).
TEMPERATURE-PRESSURE RELIEF VALVE
This water heater is provided with a properly rated/sized and cered
combinaon Temperature-Pressure Relief Valve (T&P valve) by the
manufacturer. The valve is cered by a naonally recognized tesng
laboratory that maintains periodic inspecon of producon of listed
equipment of materials as meeng the requirements for
Relief Valves
for Hot Water Supply Systems
,
ANSI Z21.22
•
CSA 4.4
, and the code
requirements of
ASME
.
If replaced, the new T&P valve must meet the requirements of local
codes, but not less than a combinaon Temperature-Pressure Relief
Valve rated/sized and cered as indicated in the above paragraph.
The new valve must be marked with a maximum set pressure not to
exceed the marked hydrostac working pressure of the water heater
(150 psi = 1,035 kPa) and a discharge capacity not less than the water
heater Btu/hr or kW input rate as shown on the water heater’s model
rang label.
Normal opera�on of the water heater can cause
it to become sufficiently over-heated and/or
over-pressurized that it can explode, resul�ng in
property damage, sever injury, or death.
To avoid this hazard, you must install a properly-
sized temperature-pressure relief valve in opening
provided.
• The temperature-pressure relief valve must
comply with ANSI Z21.22-CSA 4.4 and ASME
code.
• Do not plug, block, or cap the discharge line.
⚠
WARNING
Explosion Hazard
Note:
In addion to the factory-installed Temperature-Pressure Relief
Valve on the water heater, each remote storage tank that may
be installed and piped to a water heang appliance must also
have its own properly sized, rated and approved Temperature-
Pressure Relief Valve installed. Contact Technical Support for
assistance in sizing a Temperature-Pressure Relief Valve for
remote storage tanks. See the contact informaon label on
the water heater.
For safe operaon of the water heater, the Temperature-Pressure Relief
Valve must not be removed from its designated opening nor plugged.
The Temperature-Pressure Relief Valve must be installed directly into
the ng of the water heater designed for the relief valve. Install
discharge piping so that any discharge will exit the pipe 6 inches above
an adequate oor drain, or external to the building. In cold climates
it is recommended that it be terminated at an adequate drain inside
the building. Be certain that no contact is made with any live electrical
part. The discharge opening must not be blocked or reduced in size
under any circumstances. Excessive length, over 30 feet (9.14 m), or
use of more than four elbows can cause restricon and reduce the
discharge capacity of the valve.
No valve or other obstrucon is to be placed between the Temperature-
Pressure Relief Valve and the tank. Do not connect discharge piping
directly to the drain. Posion the end of the discharge pipe directly
above the drain, poinng downward, with an air gap of 6” (15.3 cm)
above a suitable drain. To prevent bodily injury, hazard to life, or
property damage, the relief valve must be allowed to discharge water
in adequate quanes should circumstances demand. If the discharge
pipe is not connected to a drain or other suitable means, the water
ow may cause property damage.
Property Damage Hazard
While the water heater is in rou�ne opera�on, it can
release hot water from the temperature-pressure relief
valve discharge pipe in quan��es that could cause
damage to the surroundings.
Locate the water heater near an adequate drain and
in an area where water from the temperature-pres-
sure relief valve discharge pipe will not result in
damage to the area or the lower floors of the
structure.
⚠
CAUTION
T&P Valve Discharge Pipe Requirements:
• Shall not be smaller in size than the outlet pipe size of the valve,
or have any reducing couplings or other restricons.
• Shall not be plugged or blocked.
• Shall not be exposed to freezing temperatures.
• Shall be of material listed for hot water distribuon.
• Shall be installed so as to allow complete drainage of both the
Temperature-Pressure Relief Valve and the discharge pipe.
• Must terminate six inches above a oor drain or external to the
building. In cold climates, it is recommended that the discharge
pipe be terminated at an adequate drain inside the building.
• Shall not have any valve or other obstrucon between the relief
valve and the drain.
⚠
DANGER
Burn Hazard
The discharge water from the temperature-pressure
relief valve is hot enough to cause burns.
Keep clear of the temperature-pressure relief valve
discharge outlet.
The Temperature-Pressure Relief Valve must be manually operated at
least twice a year.
Caution should be taken to ensure that (1) no one is
in front of or around the outlet of the Temperature-Pressure Relief Valve
discharge line
, and (2)
the water manually discharged will not cause any
bodily injury or property damage because the water may be extremely
hot.
If aer manually operang the valve, it fails to completely reset
and connues to release water, immediately close the cold water inlet
to the water heater, follow the draining instrucons in this manual,
and replace the Temperature-Pressure Relief Valve with a properly
rated/sized new one.
Installaon Requirements
High-Eciency Commercial Gas Water Heaters • 23
Note:
The purpose of a Temperature-Pressure Relief Valve is to
prevent excessive temperatures and pressures in the storage
tank. The T&P valve is not intended for the constant relief of
thermal expansion. A properly sized thermal expansion tank
must be installed on all closed systems to control thermal
expansion. See
Closed Water Systems
(page 21)
and
Thermal
Expansion
(page 21).
If you do not understand these instrucons or have any quesons
regarding the Temperature-Pressure Relief Valve contact Technical
Support for assistance. See the contact informaon label on the water
heater.
CONDENSATE DRAIN
The water heaters covered in this manual are condensing appliances
and require a building drain to be located in close proximity to allow
the condensate to drain safely.
Condensate drains from the water heater at the exhaust/condensate
elbow located at the boom. The eld-installed condensate drain line
must not be elevated above the condensate drain connecon on the
exhaust/condensate elbow. See
Figure 15
(page 23).
If the condensate does not drain properly it will build up in the exhaust
(vent) elbow. This will restrict the ow of ue gases and cause the
Blocked Exhaust pressure switch to open its contacts. The control
system monitors all pressure switches, if the Blocked Exhaust Switch
contacts are open the control system will lockout and disable heang
operaon. The “Blocked Exhaust” Fault message will be displayed on
the control system’s LCD. See
Fault and Alert Conditions
(page 84).
The Condensate Clean-out Cap must be on and ght when unit is in
operaon.
The exhaust elbow has a built in condensate trap. Do not install an
addional trap in the condensate drain piping. See
Figure 15
(page
23).
Note:
If the “Blocked Exhaust“ Fault message is ever displayed on
the control system LCD, check the condensate drain rst and
ensure it is not blocked.
EXHAUST (VENT)
ELBOW
THIS SIDE VIEW
OF EXHAUST
ELBOW AND
ARROW INDICATE
THE LOCATION OF
THE PRESSURE
PORT
BUILDING
DRAIN
CONDENSATE
CLEANOUT CAP
CONDENSATE DRAIN
LINE - FIELD INSTALLED
CONDENSATE
DRAIN LINE
CONNECTION
Figure 15. Exhaust/Condensate Elbow
Condensate Drain Water Trap
Do not remove the factory-installed exhaust/condensate elbow for any
reason. See
Figure 15
. The water heater’s vent pipe is under a slight
posive pressure while unit is in operaon. The water trap prevents
ue gases from escaping into the installed space. The exhaust elbow
has a “built in” condensate trap. Do not install an addional trap in
the condensate drain piping. See
Figure 15
(page 23) and
Condensate
Drain Installation
(page 47).
Condensate PH Level
The condensate drains from the water heater’s covered in this manual
have pH levels between 4.3 and 5.0. Install a commercially available
neutralizing kit if required by local codes.
Note:
Lower pH levels are acidic. Do not connect a metal drain
line, such as copper, to the water heater for this reason. See
Condensate Drain Installation
(page 47).
COMBUSTIBLE MATERIAL STORAGE
Read instruction manual before installing, using or servicing water
heater.
⚠
WARNING
Fire or Explosion Hazard
Under certain circumstances, the water heater can
explode and catch fire, resul�ng in property damage,
personal injury, or death.
Do the following to avoid these condi�ons:
• Do not store or use gasoline or other flammable
vapors and liquids in the vicinity of this or any other
appliance.
• Avoid all ignition sources if you smell gas.
• Do not expose water heater controls to excessive gas
pressure.
• Use only the gas shown on the water heater rating
label.
• Maintain required clearances to combustibles.
• Keep ignition sources away from faucets after
extended periods of non-use.
Keep appliance area clear and free of combusble materials, gasoline
and other ammable vapors and liquids.
24 • High-Eciency Commercial Gas Water Heaters
Installaon Requirements
CONTAMINATED AIR
• Install water heater in accordance with
the Instruction Manual and NFPA 54 or
CAN/CSA-B149.1.
• To avoid injury, combustion and ventilation air
must be taken from outdoors.
• Do not place chemical vapor emitting products
near water heater.
Breathing carbon monoxide can cause brain damage or death. Always
read and understand instruc�on manual.
⚠
WARNING
Breathing Hazard - Carbon Monoxide Gas
Corrosion of the flue ways and vent system may occur if air for
combuson contains certain chemical vapors. Such corrosion may
result in failure and risk of asphyxiaon.
Combuson air that is contaminated can greatly diminish the life span
of the water heater and water heater components such as igniters and
burners. Propellants of aerosol sprays, beauty shop supplies, water
soener chemicals and chemicals used in dry cleaning processes that
are present in the combuson, venlaon or ambient air can cause
such damage.
Do not store products of this sort near the water heater. Air which is
brought in contact with the water heater should not contain any of
these chemicals. If necessary, uncontaminated air should be obtained
from remote or outdoor sources. The limited warranty is voided when
failure of water heater is due to a corrosive atmosphere. (See limited
warranty for complete terms and condions).
If the water heater will be used in beauty shops, barber shops, cleaning
establishments, or self-service laundries with dry cleaning equipment,
it is imperave that the water heater(s) be installed in a Direct Vent
conguraon so that all air for combuson is derived directly from
the outdoor atmosphere through a sealed intake-air pipe. See
Venting
Installation
(page 28).
AIR REQUIREMENTS
• Install water heater in accordance with
the Instruction Manual and NFPA 54 or
CAN/CSA-B149.1.
• To avoid injury, combustion and ventilation air
must be taken from outdoors.
• Do not place chemical vapor emitting products
near water heater.
Breathing carbon monoxide can cause brain damage or death. Always
read and understand instruc�on manual.
⚠
WARNING
Breathing Hazard - Carbon Monoxide Gas
For safe operaon an adequate supply of fresh uncontaminated air for
combuson and venlaon must be provided.
An insucient supply of air can cause recirculaon of combuson
products resulng in contaminaon that may be hazardous to life.
Such a condion oen will result in a yellow, luminous burner ame,
causing soong of the combuson chamber, burners and ue tubes
and creates a risk of asphyxiaon.
Do not install the water heater in a conned space unless an adequate
supply of air for combuson and venlaon is brought in to that space
using the methods described in
Confined Space
.
Never obstruct the ow of venlaon air. If you have any doubts or
quesons at all, call your gas supplier. Failure to provide the proper
amount of combuson air can result in a re or explosion and cause
property damage, serious bodily injury or death.
Unconfined Space
An Unconned Space is one whose volume
is not
less
than
50 cubic feet
per 1,000 Btu/hr (4.8 cubic meters per kW) of the total input rang of all
appliances installed in the space. Rooms communicang directly with
the space, in which the appliances are installed, through openings not
furnished with doors, are considered a part of the unconned space.
Makeup air requirements for the operaon of exhaust fans, kitchen
ventilation systems, clothes dryers and fireplaces shall also be
considered in determining the adequacy of a space to provide
combuson, venlaon and diluon air.
Unusually Tight Construction
In unconned spaces in buildings, inltraon may be adequate to
provide air for combuson, venlaon and diluon of ue gases.
However, in buildings of unusually ght construcon (for example,
weather stripping, heavily insulated, caulked, vapor barrier, etc.)
additional air must be provided using the methods described in
Confined Space
.
Confined Space
A Conned Space is one whose volume
is
less than
50 cubic feet per
1,000 Btu/hr (4.8 cm per kW) of the total input rang of all appliances
installed in the space.
Openings must be installed to provide fresh air for combustion,
venlaon and diluon in conned spaces. The required size for the
openings is dependent on the method used to provide fresh air to
the conned space
and
the total Btu/hr input rang of all appliances
installed in the space.
Direct Vent Appliances
Appliances installed in a Direct Vent conguraon that derive all
air for combuson from the outdoor atmosphere through sealed
intake-air piping are not factored in the total appliance input Btu/hr
calculaons used to determine the size of openings providing fresh
air into conned spaces.
Exhaust Fans
Where exhaust fans are installed, addional air shall be provided to
replace the exhausted air. When an exhaust fan is installed in the
same space with a water heater, sucient openings to provide fresh
air must be provided that accommodate the requirements for all
appliances in the room and the exhaust fan. Undersized openings will
Installaon Requirements
High-Eciency Commercial Gas Water Heaters • 25
cause air to be drawn into the room through the water heater’s vent
system causing poor combuson. Soong, serious damage to the water
heater and the risk of re or explosion may result. It can also create
a risk of asphyxiaon.
Louvers and Grilles
The free areas of the fresh air openings in the instrucons that follow
do not take in to account the presence of louvers, grilles or screens
in the openings.
The required size of openings for combuson, venlaon and diluon
air shall be based on the “net free area” of each opening. Where the
free area through a design of louver or grille or screen is known, it
shall be used in calculang the size of the opening required to provide
the free area specied. Where the louver and grille design and free
area are not known, it shall be assumed that wood louvers will have
25% free area and metal louvers and grilles will have 75% free area.
Non motorized louvers and grilles shall be xed in the open posion.
FRESH AIR OPENINGS FOR CONFINED SPACES
The following instrucons shall be used to calculate the size, number
and placement of openings providing fresh air for combustion,
venlaon and diluon in conned spaces. The illustraons shown in
this secon of the manual are a reference for the openings that provide
fresh air into conned spaces only.
Do not
refer to these illustraons
for the purpose of vent installaon. See
Venting Installation
(page 28)
for complete venng installaon instrucons.
Outdoor Air Through Two Openings
Figure 16. Outdoor Air Through Two Openings
The conned space shall be provided with two permanent openings,
one commencing within 12 inches (30 cm) of the top and one
commencing within 12 inches (30 cm) of the boom of the enclosure.
The openings shall communicate directly with the outdoors. See
Figure
16
.
Each opening shall have a minimum free area of one square inch per
4,000 Btu/hr (550 mm
2
per kW) of the aggregate input rang of all
appliances installed in the enclosure. Each opening shall not be less
than 100 square inches (645 cm
2
).
Outdoor Air Through One Opening
Figure 17. Outdoor Air Through One Opening
Alternavely a single permanent opening, commencing within 12
inches (30 cm) of the top of the enclosure, shall be provided. See
Figure 17
. The water heater shall have clearances of at least 1 inch
(2.5 cm) from the sides and back and 6 inches (15 cm) from the front
of the water heater. The opening shall directly communicate with the
outdoors or shall communicate through a vercal or horizontal duct
to the outdoors or spaces that freely communicate with the outdoors
and shall have a minimum free area of the following:
One square inch per 3000 Btu/hr (700 mm
2
per kW) of the total input
rang of all appliances located in the enclosure, and
Not less than the sum of the areas of all vent connectors in the space.
Outdoor Air Through Two Horizontal Ducts
Figure 18. Outdoor Air Through Two Horizontal Ducts
The conned space shall be provided with two permanent horizontal
ducts, one commencing within 12 inches (30 cm) of the top and one
commencing within 12 inches (30 cm) of the boom of the enclosure.
26 • High-Eciency Commercial Gas Water Heaters
Installaon Requirements
The horizontal ducts shall communicate directly with the outdoors.
See
Figure 18
.
Each duct opening shall have a minimum free area of 1 square inch
per 2,000 Btu/hr (1100 mm
2
per kW) of the aggregate input rang of
all appliances installed in the enclosure.
When ducts are used, they shall be of the same cross seconal area
as the free area of the openings to which they connect. The minimum
dimension of rectangular air ducts shall be not less than 3 inches.
Outdoor Air Through Two Vertical Ducts
The illustraons shown in this secon of the manual are a reference
for the openings that provide fresh air into conned spaces only.
Do not
refer to these illustraons for the purpose of vent installaon.
See
Venting Installation
(page 28) for complete venng installaon
instrucons.
Figure 19. Outdoor Air Through Two Vertical Ducts
The conned space shall be provided with two permanent vercal
ducts, one commencing within 12 inches (30 cm) of the top and one
commencing within 12 inches (30 cm) of the boom of the enclosure.
The vercal ducts shall communicate directly with the outdoors. See
Figure 19
.
Each duct opening shall have a minimum free area of 1 square inch
per 4,000 Btu/hr (550 mm
2
per kW) of the aggregate input rang of
all appliances installed in the enclosure.
When ducts are used, they shall be of the same cross seconal area
as the free area of the openings to which they connect. The minimum
dimension of rectangular air ducts shall be not less than 3 inches.
Air From Other Indoor Spaces
Figure 20. Air From Other Indoor Spaces
The conned space shall be provided with two permanent openings,
one commencing within 12 inches (30 cm) of the top and one
commencing within 12 inches (30 cm) of the boom of the enclosure.
See
Figure 20
.
Each opening shall communicate directly with an addional room(s)
of sucient volume so that the combined volume of all spaces meets
the criteria for an Unconned Space.
Each opening shall have a minimum free area of 1 square inch per
1,000 Btu/hr (1100 mm
2
per kW) of the aggregate input rang of all
appliances installed in the enclosure. Each opening shall not be less
than 100 square inches (645 cm
2
).
Installaon Requirements
High-Eciency Commercial Gas Water Heaters • 27
MASSACHUSETTS INSTALLATION REQUIREMENTS
Commonwealth Of Massachusetts
For all side wall terminated, horizontally vented power vent, direct
vent, and power direct vent gas fueled water heaters installed in every
dwelling, building or structure used in whole or in part for residenal
purposes, including those owned or operated by the Commonwealth
and where the side wall exhaust vent terminaon is less than seven
(7) feet above nished grade in the area of the venng, including but
not limited to decks and porches, the following requirements shall
be sased:
Installing Carbon Monoxide Detectors
At the me of installaon of the side-wall horizontal-vented gas-fueled
equipment, the installing plumber or gas-er shall observe that a
hard-wired carbon-monoxide detector, with an alarm and baery
back-up, is installed on the oor level where the gas equipment is to be
installed. In addion, the installing plumber or gas-er shall observe
that a baery-operated or hard-wired carbon-monoxide detector,
with an alarm, is installed on each addional level of the dwelling,
building, or structure served by the side-wall horizontal-vented gas-
fueled equipment. It shall be the responsibility of the property owner
to secure the services of qualied licensed professionals for the
installaon of hard-wired carbon-monoxide detectors.
In the event that the side-wall horizontally-vented gas-fueled
equipment is installed in a crawl space or an ac, the hard-wired
carbon-monoxide detector, with alarm and baery back-up, may be
installed on the next adjacent oor level.
In the event that the requirements of this subdivision can not be met at
the me of compleon of installaon, the owner shall have a period of
thirty (30) days to comply with the above requirements provided that
during said thirty (30) day period, a baery-operated carbon-monoxide
detector, with an alarm, shall be installed.
Approved Carbon Monoxide Detectors
Each carbon-monoxide detector as required in accordance with the
above provisions shall comply with
NFPA 720
and be
ANSI/UL 2034
listed
and
CSA
cered.
Signage
A metal or plasc idencaon plate shall be permanently mounted
to the exterior of the building at a minimum height of eight (8) feet
above grade directly in line with the exhaust vent terminal for the
horizontally-vented gas-fueled heang appliance or equipment. The
sign shall read, in print size no less than one-half (1/2) inch in size,
“gas
vent directly below. Keep clear of all obstructions.”
Inspection
The state or local gas inspector of the side-wall horizontally-vented
gas-fueled equipment shall not approve the installaon unless, upon
inspecon, the inspector observes carbon-monoxide detectors and
signage installed in accordance with the provisions of
248 CMR 5.08(2)
(a) 1 through 4
.
Exemptions
The following equipment is exempt from
248 CMR 5.08(2)(a)1 through 4
:
1. The equipment listed in Chapter 10 entitled “Equipment Not
Required To Be Vented” in the most current edion of
NFPA 54
as
adopted by the Board; and
2. Product Approved side-wall horizontally-vented gas-fueled
equipment installed in a room or structure separate from the
dwelling, building, or structure used in whole or in part for
residenal purposes.
Manufacturer Requirements - Gas Equipment Venng System Provided
When the manufacturer of Product Approved side-wall horizontally-
vented gas-fueled equipment provides a venng system design or
venng system components with the equipment, the instrucons
provided by the manufacturer for installaon of the equipment and
the venng system shall include:
1. Detailed instrucons for the installaon of the venng-system
design or the venng-system components
2. A complete parts list for the venng-system design or venng
system.
Manufacturer Requirements - Gas Equipment Venting System Not Provided
When the manufacturer of a Product Approved side-wall
horizontally-vented gas-fueled equipment does not provide the parts
for venng the ue gases, but idenes “special venng systems,” the
following requirements shall be sased by the manufacturer:
1. The referenced “special venting system” instructions shall be
included with the appliance or equipment installaon instrucons.
2. The “special venng systems” shall be Product Approved by the
Board, and the instrucons for that system shall include a parts list
and detailed installaon instrucons.
A copy of all installaon instrucons for all Product Approved side-wall
horizontally-vented gas-fueled equipment, all venng instrucons, all
parts lists for venng instrucons, and/or all venng-design instrucons
shall remain with the appliance or equipment at the compleon of
the installaon.
28 • High-Eciency Commercial Gas Water Heaters
VENTING INSTALLATION
Breathing carbon monoxide can cause brain damage or death. Always read
and understand instruc�on manual.
• Install vent system In accordance with codes.
• Do not operate water heater if flood
damaged.
• Install water heater in accordance with the
instruction manual.
• Do not operate if soot buildup is present.
• Do not obstruct water heater air intake(s)
with insulating jacket or blanket.
• Do not place chemical vapor emitting
products near water heater.
• Install gas and carbon monoxide detectors for
additional safety.
• Never operate the heater unless it is vented
to the outdoors and has adequate air supply
to avoid risks of improper operation, fire,
explosion or asphyxiation.
• Analyze the entire vent system to make sure
that condensate will not become trapped in a
section of vent pipe and therefore reduce the
open cross sectional area of the vent.
⚠
WARNING
Breathing Hazard - Carbon Monoxide Gas
Never operate the water heater unless it is vented to outdoors. The
instrucons in this secon of the manual must be followed to avoid
choked combuson or recirculaon of ue gases. Such condions
cause soong of the combuson chamber, burners, and ue tubes,
and creates a risk of asphyxiaon.
GENERAL VENTING INFORMATION
The water heaters covered in this manual are Category IV appliances
and may be installed in either a Power Vent or Direct Vent conguraon.
Approved Materials
Approved vent and intake-air pipe materials that may be used in the
United States:
PVC pipe materials:
• DWV ASTM-D2665 or CSA B181.2
• Schedule 40, 80, 120 ASTM-D1785 or CSA B137.3
• SDR Series ASTM-2241 or CSA B137.3
CPVC pipe materials:
• CPVC 41 ASTM-D2846 or CSA B137.6
• Schedule 40, 80 ASTM-F441 or CSA B137.6
• SDR Series ASTM-F442
Polypropylene
(page 36)
• M & G Duravent PolyPro vent system
• Centrotherm InnoFlue vent system
AL29-4C® Vent Installations
(page 36).
• HeatFab Saf-T Vent
• Duravent FasNSeal
Approved vent pipe materials that must be used in Canada:
• ULC S636 PVC / CPVC
• ULC S636 Polypropylene
• AL29-4C Stainless Steel
Approved intake-air pipe materials that must be used in Canada:
PVC pipe materials:
• DWV ASTM-D2665 or CSA B181.2
• Schedule 40, 80, 120 ASTM-D1785 or CSA B137.3
• SDR Series ASTM-D2241 or CSA B137.3
CPVC pipe materials:
• SDR Series ASTM-D2241 or CSA B137.3
• Schedule 40, 80 ASTM-F441 or CSA B137.6
• SDR Series ASTM-F442
Polypropylene
• M & G Duravent PolyPro vent system
• Centrotherm InnoFlue vent system
AL29-4C Stainless Steel
• HeatFab Saf-T Vent
• Duravent FasNSeal
Where applicable, the installaon of the venng system should be done
in accordance with the venng system manufacturer’s instrucons.
Note:
The use of cellular core PVC (
ASTM F891
), cellular core CPVC,
or Radel
®
(polyphenolsulfone) in non-metallic venng systems
is prohibited. Covering non-metallic vent pipe and ngs with
thermal insulaon is prohibited.
CATEGORY IV APPLIANCES
Category IV
appliances operate with a posive vent (exhaust) stac
pressure and with vent-gas temperatures low enough to produce
condensate in the vent piping.
Power Vent Configurations
Power Vent conguraons derive all combuson air from the room
where they are installed and discharge all ue gases to the outdoor
atmosphere through a sealed vent (exhaust) pipe. Power vent
conguraons have one vent pipe connected to the water heater which
can be terminated in a vercal or horizontal arrangement. See
Figure
52
and
Figure 53
(page 43).
Direct Vent Configurations
Direct Vent conguraons derive all combuson air directly from the
outdoor atmosphere through a sealed intake-air pipe and discharge
all flue gases to the outdoor atmosphere through a sealed vent
(exhaust) pipe. Direct Vent conguraons have two pipes connected
to the water heater, one vent pipe and one intake-air pipe. Direct
Vent configurations can be terminated in one of seven different
arrangements. See
Figure 54
through
Figure 60
(page 43).
Venng Installaon
High-Eciency Commercial Gas Water Heaters • 29
GENERAL VENTING INSTRUCTIONS
These instrucons must be followed on all installaons.
1.
Do not
install the water heater in a Power Vent conguraon
unless there is adequate supply of fresh air. See
Air Requirements
(page 24). If the installaon space does not provide an adequate
supply of fresh air the water heater must be installed in a Direct
Vent conguraon.
2. If the water heater is to be installed in a beauty shop, barber shop,
cleaning establishment, a laundry with dry cleaning equipment
or any space with contaminated air it is imperave that the water
heater(s) be installed in a Direct Vent conguraon so that all air
for combuson is derived from the outdoor atmosphere.
3. The vent and intake-air piping must terminate outdoors.
4. The minimum clearance from combusble materials for the vent
(exhaust) and intake-air piping shall be 0 inches. Vent piping passing
through a combusble wall or ceiling must be a connuous run
(no joints).
5. The water heater must be protected from freezing down-dras
during shutdown periods.
6. The vent (exhaust) pipe must not be combined or connected to any
other appliance’s vent system or chimney.
7. The intake-air pipe must not be combined or connected to any
other appliance’s intake-air piping.
8. Locate the water heater where the vent (exhaust) and intake-air
piping will remain within the maximum equivalent lengths allowed.
See
Venting Requirements
(page 29).
9. Do not install the vent or intake-air piping in a manner that will
allow water to be trapped in the piping.
10. The vent (exhaust) and intake-air piping must be pitched at a
minimum of 2% grade back to the water heater (to allow drainage
of condensate).
11. Do not anchor the vent or intake-air pipe directly to framed walls,
oors or ceilings unless rubber isolaon pipe hangers are used to
prevent vibraon noise from being transmied.
12. Use only approved vent/intake-air pipe sizes and materials. See
Venting Requirements
(page 29).
13. Use only factory supplied vent and intake-air, concentric or low
prole terminaons. See
Venting Requirements
(page 29).
14. Do not locate the vent (exhaust) or intake-air terminaons where
they would be objeconable due to noise at the terminaon(s).
This includes locaons close to or across from windows and doors.
15. Direct venng into dead air spaces such as alleys, atriums, and inside
corners can cause recirculaon of ue gases. Recirculaon of ue
gases will cause soong, premature failure of the heat exchanger
and icing of the combuson air intake during severe cold weather.
To prevent the recirculaon of ue gases, maintain as much distance
as possible between the intake-air and vent terminaons.
16. Do not locate the vent terminaon over public walkways or a public
area where condensate or vapor can cause a nuisance or ice hazard.
17. Ensure that the screens in the factory supplied terminaons are
securely installed to prevent blockage in the vent system.
18. Stress levels in pipe/fittings can be significantly increased by
improper installaon. If rigid pipe clamps are used to hold the pipe in
place, or if the pipe cannot move freely through a wall penetraon,
the pipe may be stressed, or high thermal stresses may be formed
when the pipe heats up and expands. Install accordingly to minimize
such stresses.
19. Carefully read the
Venting Requirements
and then proceed to the
Venting Installation Sequence
(page 31).
VENTING REQUIREMENTS
Field-Supplied PVC Fittings
Field-supplied ngs should be equivalent to the piping material being
installed. Field-installed/supplied ngs will add equivalent length
to the vent or intake-air piping as indicated below. All eld-supplied/
installed ngs and piping must be factored into the equivalent length
calculaons.
• 90° elbows (short or long radius) are equivalent to 5 linear feet
(152 cm) of pipe.
• 45° elbows (short or long radius) are equivalent to 2.5 linear feet
(76 cm) of pipe.
Note:
See
Table 13
(page 37)
and
Table 14
(page 37) for equivalent
linear pipe length of AL29-4C
®
45° and 90° elbows.
Primer and Cement
Tetrahydrofuran (THF) primer should be used to prepare the surfaces
of pipe and ngs for solvent welding. If CPVC pipe and ngs are
used, then the proper cement must be used for all joints, including
joining the pipe to the factory provided terminaons (PVC material).
PVC Materials should use ASTM D-2564 Grade Cement; CPVC Materials
should use ASTM F-493 Grade Cement.
Pipe Size Requirements
The water heaters covered in this manual are tested and cered to
use exhaust vent and intake air pipe diameters of 2”, 3”, 4”, and 6”.
See
Table 7
,
Table 8
, and
Table 9
(page 30)
for correct pipe diameter,
lengths, and amount of 90˚ and 45˚ bends.
Note:
Install the pipe size required for the installed equivalent length
of each pipe independently. For example, if the intake-air pipe
will be 70 feet equivalent length or less and the vent pipe will
be more than 70 feet equivalent length; the intake-air pipe must
be installed using 4 inch pipe and the vent must be installed
using 6 inch pipe.
Note:
See
Table 13
(page 37)
and
Table 14
(page 37)
for equivalent
linear pipe length of AL29-4C
®
45° and 90° elbows.
There is no minimum equivalent length requirement for the intake
air pipe.
The minimum equivalent length requirement for the exhaust pipe is
7 feet for all models.
30 • High-Eciency Commercial Gas Water Heaters
Venng Installaon
Factory Supplied Fittings
The 119 gallon water heater ships with two (2) factory supplied 4 inch
terminaons (PVC 45° elbows with debris screen). If 6 inch intake-air
or vent pipe is installed, factory supplied 6 inch terminaons must be
used (PN: 100111626).
The 60 gallon and 100 gallon water heaters ship with two factory
supplied 3 inch terminaons (PVC 45 deg elbows with debris screen).
Factory supplied vent and intake-air terminaons or concentric and
low prole terminaons must be used. If 2 or 4 inch intake-air or vent
pipe is installed, factory supplied terminaons must be installed. (PN:
100386033 for 2 inch and 100110909 for 4 inch). Factory supplied
terminations and installed fittings (exhaust elbow and intake-air
connecon) add zero equivalent length to the vent and intake-air
piping.
Note:
Three-inch vent and/or intake pipe as well as 3 inch terminaons
previously used on older 300 and 400 models must be replaced
with four-inch or six-inch pipe and four-inch or six-inch
terminaons depending on installed length.
Table 7. PVC/CPVC Equivalent Length and
Maximum Number of Elbows - 60 Gallon Models
Number of 90°
Elbows Installed
Maximum Feet (Meters)
2 Inch Pipe 3 Inch Pipe 4 Inch Pipe
One (1) 70 (21.3) 95 (28.9) 145 (44.1)
Two (2) 65 (19.8) 90 (27.4) 140 (42.6)
Three (3) 60 (18.2) 85 (25.9) 135 (41.1)
Four (4) 55 (16.7) 80 (24.3) 130 (39.6)
Five (5) N/A N/A 125 (38.1)
Six (6) N/A N/A 120 (36.5)
Table 8. PVC/CPVC Equivalent Length and
Maximum Number of Elbows - 100 Gallon Models
Model
Maximum Feet (Meters)
Maximum Number of
Elbows
2” Pipe 3” Pipe 4” Pipe 2” Pipe 3” Pipe 4” Pipe
150 50 (15.2) 150 (45.72) 200 (60.96) 4 4 6
199 40 (12.2) 150 (45.72) 200 (60.96) 4 4 6
250 20 (6.10) 150 (45.72) 200 (60.96) 2 4 6
Table 9. PVC/CPVC Equivalent Length and
Maximum Number of Elbows - 119 Gallon Models
Number of 90°
Elbows Installed
Maximum Feet (Meters)
4 Inch Pipe 6 Inch Pipe
One (1) 95 (28.9) 145 (44.1)
Two (2) 90 (27.4) 140 (42.6)
Three (3) 85 (25.9) 135 (41.1)
Four (4) 80 (24.3) 130 (39.6)
Five (5) 75 (22.8) 125 (38.1)
Six (6) 70 (21.3) 120 (36.5)
INTAKE AIR CONNECTION
The water heaters covered in this manual are factory equipped with a
unique Combuson Blower and intake-air connecon Tee ng. The
Tee is a 3” x 3” x 1/2” ng. The intake-air connecon Tee ng has
a hose barb installed in the 1/2 inch branch to connect the Blocked
Intake Air switch sensing tube.
Figure 21. Intake Air Connection (60 Gallon)
Figure 22. Intake Air Connection (100 Gallon)
Figure 23. Intake Air Connection (119 Gallon)
Ensure that the hose barb installed in the Tee ng
IS NOT
facing
down towards the ground (180° - 6 o’clock posion) before venng
installaon begins. The barb ng must be angled between 90° and
no more than 130° as shown in
Figure 24
(page 31). If the barb ng
is facing down, residual condensate that occasionally forms in the
intake-air pipe can drain into the Blocked Intake Air switch through
the aached sensing tube and damage the switch. This condion can
also lead to Blocked Intake Air fault condions and associated control
system lockouts.
Venng Installaon
High-Eciency Commercial Gas Water Heaters • 31
90° TO 130°
END VIEW
Figure 24. Intake Air Connection Hose Barb Angle Range for Proper Operation
The intake-air Tee ng is factory-installed with the 1/2 inch branch
and hose barb angled to the right at approximately 130° when viewed
from the end. See
Figure 24
. The Tee ng’s 1/2 inch branch and
hose barb must not be angled any lower (towards the ground) than
this factory specicaon. Angling higher, up to a 90° posion, will not
adversely aect operaon and is acceptable.
Large Hose Clamp
Figure 25. Intake Air Tee Fitting - Side View
Inspect/-Adjust Intake Air Tee Fitting
Inspect the angle of the tee ng’s 1/2 inch branch and hose barb
while viewing from the end of the tee. See
Figure 24
. If the angle of
the tee ng 1/2 inch branch and hose barb is lower than shown,
adjustment will be necessary. To adjust the intake-air tee ng angle,
follow the steps listed below.
1. Ensure that the water heater is turned o at the on/o switch on
the front of the water heater.
2. Disconnect the blocked intake-air switch sensing tube. See
Figure
26
for the locaon.
3. Loosen the large hose clamp on the Fernco coupling that connects
the intake-air connecon pipe to the combuson blower. See
Figure
25
(page 31).
4. Adjust the angle of the tee ng so that the 1/2 inch branch and
hose barb are at the proper angle as shown in
Figure 24
.
5. Reghten the large hose clamp on the combuson blower intake-
air Fernco coupling.
Blocked Intake
Sensing Tube
Figure 26. Blocked Intake Air Switch Sensing Tube
Required Terminations for Six-Inch Intake Air or Vent Pipe
When a six-inch intake-air or vent pipe is installed using standard
terminations, factory-supplied six-inch terminations must be
used. Contact Technical Support for assistance in ordering six-inch
terminaon(s). See the contact informaon label on the water heater.
See
Optional Terminations
(page 18)
for more informaon.
VENTING INSTALLATION SEQUENCE
1. Read
General Venting Instructions
(page 29) and
Venting
Requirements
(page 29) before proceeding. These instrucons
and requirements must be followed on all installaons.
2. Determine whether the water heater will be installed in a power-vent
or direct-vent conguraon and which vent system arrangement will
be used for the installaon. See
Venting Arrangements
(page 43).
3. Proceed to the applicable installaon instrucons:
•
Power Vent Installation
(page 31)
or
•
Direct Vent Installation
(page 32).
POWER VENT INSTALLATION
1. Read
General Venting Instructions
(page 29) and
Venting
Requirements
(page 29) before proceeding. These instrucons
and requirements must be followed in addion to the instrucons
below that are specic for power vent conguraons.
2. Determine which terminaon arrangement will be used for the
installaon: vercal or horizontal terminaon. See
Figure 46
and
Figure 47
(page 41).
3. Determine the vent pipe size for the installation. See
Venting
Requirements
(page 29).
4. Plan the layout of the vent piping backwards from the terminaon
point outdoors to the water heater. Layout the vent piping to use
a minimum of pipe and elbows.
5. Install the terminaon rst.
If the vent piping will terminate vercally through a roof, see
Vertical Termination Installation
(page 33).
32 • High-Eciency Commercial Gas Water Heaters
Venng Installaon
If the vent piping will terminate horizontally through a sidewall,
see
Horizontal Termination Installation
(page 35).
PIPE FIELD
SUPPLIED
ALUMINUM
EXHAUST/
CONDENSATE
ELBOW VENT
CONNECTION
FACTORY
INSTALLED
PIPE FIELD
SUPPLIED
REDUCER
FIELD SUPPLIED
VENT (EXHAUST) CONNECTION
Figure 27. Vent Exhaust Connection
6. When installaon of the terminaon is complete, install necessary
piping and ngs to route the vent piping back to the water heater.
7. The vent pipe must be supported properly to avoid bending or
failure. The water heater manufacturer recommends that the vent
pipe be supported every 5 feet (152 cm) of vercal run and every
3 (91 cm) of horizontal run.
8. Do not install the vent piping in a manner that will allow water to
be trapped in the piping.
9. All vent (exhaust) pipes must be pitched a minimum of 1/4 in (7 mm)
per foot back to the water heater (to allow drainage of condensate).
10. 60/100 gallon - If installing three-inch vent pipe, connect the vent
pipe to the exhaust elbow on the water heater. If installing two- or
four-inch pipe, transion to three-inch pipe at the exhaust elbow
on the water heater. The eld-installed three-inch pipe between
the elbow and the reducer coupling should be 18 in (45 cm) or
less in length.
11. 119 gallon - If installing four-inch vent pipe, connect the vent pipe
to the exhaust elbow on the water heater. If installing six-inch pipe,
transion to four-inch pipe at the exhaust elbow on the water
heater. The eld-installed four-inch pipe between the exhaust
elbow and the 6” x 4” reducer coupling should be 18 in (45 cm)
or less in length.
DIRECT VENT INSTALLATION
1. Read
General Venting Instructions
(page 29) and
Venting
Requirements
(page 29)
before proceeding. These instrucons
and requirements must be followed in addion to the instrucons
below that are specic for direct-vent conguraons.
2. Determine which direct-vent arrangement will be used for the
installaon. There are several direct-vent arrangement opons.
Figure 46
(page 40)
and
Figure 47
(page 41).
3. Determine the vent and intake-air pipe sizes to be used for the
installaon. See
Venting Requirements
(page 29).
4. Plan the layout of the vent and intake-air piping backwards from
the terminaon point outdoors to the water heater. Layout the
vent and intake-air piping to use a minimum of pipe and elbows.
5. Install the terminaons rst.
• If standard terminaons are being used, and the intake-air
or vent piping will terminate vercally through a roof, see
Vertical Termination Installation
(page 33).
• If standard terminaons are being used, and the intake-air or
vent piping will terminate horizontally through a sidewall, see
Horizontal Termination Installation
(page 35).
• If a low-prole terminaon will be used, see
Table 15
(page
42).
6. When installaon of the terminaon(s) is complete, install the
necessary piping and ngs to route the intake-air and vent piping
back to the water heater. The intake-air and vent piping must be
supported properly to avoid bending or failure. The water heater
manufacturer recommends that the vent and intake-air piping be
supported every 5 (152 cm) of vercal run and every 3 (91 cm)
of horizontal run.
7. Do not install the vent or intake-air piping in a manner that will
allow water to be trapped in the piping.
8. A eld-supplied condensate tee ng and drain hose must be
installed in the intake-air piping near the water heater in colder
climates with heavy snow accumulaons and in areas that regularly
experience high humidity. The drain hose must be routed to an
adequate oor drain separate from any other condensate drain
hoses. See
Figure 28
(page 33).
Note:
Snow being pulled into the intake-air piping and
then melng can lead to excessive amounts of water
accumulaon and damage to the water heater
components. Warm, humid outdoor air can lead to
excessive condensaon inside the intake-air piping and
may also damage water heater components.
9. The intake-air and vent (exhaust) piping must be pitched a minimum
of 1/4 in (7 mm) per foot back to the water heater (to allow drainage
of condensate).
10. 119 gallon - If installing four-inch vent pipe, connect the vent pipe
to the exhaust elbow on the water heater. If installing six-inch vent
pipe, transion to four-inch pipe at the exhaust elbow on the water
heater. The eld-installed four-inch pipe between the exhaust
elbow and the 6” x 4” reducer coupling should be 18 in (45 cm)
or less in length.
11. 60/100 gallon - If installing three-inch vent pipe, connect the vent
pipe to the exhaust elbow on the water heater. If installing two- or
four-inch vent pipe, transion to three-inch pipe at the exhaust
elbow on the water heater. The eld-installed three-inch pipe
between the exhaust elbow and the reducer coupling should be
18 in (45 cm) or less in length.
Venng Installaon
High-Eciency Commercial Gas Water Heaters • 33
INTAKE AIR CONDENSATE TEE INSTALLATION
INSTALL TEE FITTING AS CLOSE
TO WATER HEATER INTAKE AIR
CONNECTION AS POSSIBLE
FIELD SUPPLIED TEE
WITH HOSE BARB
FITTING INSTALLED
119G ONLY
FACTORY
INSTALLED
INTAKE AIR
CONNECTION
(REDUCER)
INTAKE AIR
CONNECT FIELD
SUPPLIED FLEXIBLE
DRAIN HOSE TO BARB
FITTING AND FORM A
LOOP WATER TRAP IN
DRAIN HOSE
RUN DRAIN HOSE
TO SUITABLE FLOOR
DRAIN SEPARATELY
FROM OTHER
CONDENSATE DRAINS
Figure 28. Intake Air Condensate Tee Installation
12. Ensure that the intake-air screen on the intake-air connecon is
removed before connecng the intake-air pipe to the water heater.
See
Figure 29
.
Breathing carbon monoxide can cause brain damage or death. Always read
and understand instruc�on manual.
• Do not obstruct water heater air intake.
• Gas and carbon monoxide detectors are
available.
• Install water heater in accordance with the
instruction manual and applicable codes.
⚠
WARNING
Breathing Hazard - Carbon Monoxide Gas
Note:
Do not leave the screen inside the intake-air connecon in
direct-vent installaons. Once the intake-air pipe is installed,
the screen will be hidden from view and may become clogged
with debris over me. This will cause improper combuson.
INTAKE AIR SCREEN
(remove for Direct Vent)
Figure 29. Intake Air Screen
13. On 119 gallon models, if installing four-inch intake-air pipe, connect
the intake-air pipe to the intake-air connecon on the water heater.
On 60/100 gallon models, if installing three-inch intake-air pipe,
connect the intake-air pipe to the intake-air connecon on the
water heater.
14. On 119 gallon models, if installing six-inch intake-air pipe, transion
to four-inch pipe at the intake-air connecon on the water heater.
The eld-installed four-inch pipe between the intake-air connecon
and the 6” x 4” reducer coupling should be 18 in (45 cm) or less in
length. On 60/100 gallon, if installing two- or four-inch intake-air
pipe, transion to three-inch pipe at the intake-air connecon on
the water heater. The eld-installed three-inch pipe between the
intake-air connecon and the reducer coupling should be 18 in (45
cm) or less in length.
PIPE FACTORY
INSTALLED
PIPE FIELD
SUPPLIED
REDUCER
FACTORY INSTALLED
INTAKE AIR CONNECTION
INTAKE AIR
COMBUSTION
BLOWER
Figure 30. Intake-Air Connection (119-Gallon Model)
Direct Vent Air Intake Moisture Protection
The air intake piping in a direct-vent system will normally not have any
moisture accumulaon in it. However, in certain cases, moisture can
build up and needs to be drained. Typical situaons include, but are
not limited to the following:
• Cold outdoor temperature, parcularly if the air inlet is short
• High outdoor humidity
• Heater being used mostly for space heang
• Air inlet pipe has vercal rise near the heater
Installaons with any of these condions are required to provide a
moisture drain with a trap that ows to a waste drain. See
Figure 28
(page 33) and
Figure 46
(page 40) through
Figure 52
(page 43).
A horizontal secon of the air-inlet pipe near the heater should
include a 4″ x 4″ x 1/2″ (119 gallon) and 3” x 3” x 1/2” (60/100 gallon)
tee and a hose barb ng to drain the water. The tee should be as
close to the heater as is praccal. The drain tubing in any installaon
should have a loop trap and ow to an appropriate waste drain. The
air-intake drain line must be enrely separate from the exhaust vent
outlet condensate drain line.
VERTICAL TERMINATION INSTALLATION
1. Determine the locaon for the terminaon(s).
2. If installing only the vent (exhaust) piping in a power-vent
conguraon vercally through the roof, ensure that all exterior
vercal clearance requirements shown in
Figure 31
and
Figure 32
(page 35)
are being maintained. These clearances and those cited
by local and naonal codes must be maintained.
Note:
On at roof installaons, the vent terminaon must be
a minimum of 24 in (60 cm) above any parapet, vercal
34 • High-Eciency Commercial Gas Water Heaters
Venng Installaon
wall, or structure within 10 (3 m) horizontally. See
Figure 32.
3. If installing both intake-air and vent piping in a direct-vent
conguraon vercally through the roof, ensure that all exterior
vercal clearance requirements shown in
Figure 31, Figure 32
(page
35)
,
and
Figure 33
(page 35) are being maintained. These
clearances and those cited by local and naonal codes must be
maintained.
Note:
On at roof installaons, the intake-air and the vent
terminaons must be a minimum of 24 in (60 cm) above
any parapet, vercal wall or structure within 10 (3 m)
horizontally. See
Figure 32
.
4. If installing only vent piping in a power-vent conguraon vercally
through the roof, the following instrucons must be followed:
A. The vent terminaon must be oriented facing downward as
shown in
Figure 31
and
Figure 32
.
B. The boom edge of the vent terminaon must be a minimum
of 12 in (30 cm), 18 in (45 cm) in Canada, above the average
or expected snow level as shown in
Figure 31
.
5. If installing both intake-air and vent piping in a direct vent
conguraon vercally through the roof, the following instrucons
must be followed:
A. The intake-air and vent pipes must penetrate the same side
of the roof as shown in
Figure 33
(page 35).
B. The intake-air and vent terminaons must be oriented facing
downward and in the same direcon as shown in
Figure 33
(page 35).
C. The intake-air and vent terminaons must have a minimum
separaon of 24 in (61 cm) measured on the center line, as
shown in
Figure 33
. In colder climates, this separaon should
increase to at least 48 in (122 cm).
D. The boom edge of the intake-air and vent terminaons
must be a minimum of 12 in (30 cm), 18 in (45 cm) in Canada,
above the average or expected snow level as shown in
Figure
31
below.
2” (5 cm)
MAXIMUM
FACTORY SUPPLIED
STANDARD TERMINATION
POINTED DOWN TOWARDS
THE GROUND
VERTICAL TERMINATION(S) INSTALLATION
INTAKE AIR AND/OR VENT (EXHAUST)
FIELD
SUPPLIED
90° ELBOW
FIELD
SUPPLIED
STRAP/SUPPORT
FIELD SUPPLIED
PLUMBING
ROOF BOOT
OR FLASHING
MAINTAIN 12” (30 cm)
18” (45 cm) FOR CANADA
MINIMUM CLEARANCE
ABOVE HIGHEST ANTICIPATED
SNOW LEVEL.
Figure 31. Vertical Termination(s) Installation
6. When the intake-air and/or vent piping from mulple water heaters
will terminate in the same locaon, the vent terminaons can be
grouped together in close proximity 0 in (0 cm) / touching. Intake-
air terminaons can also be grouped together in close proximity
0 in (0 cm) / touching.
The distance between the closest vent and intake-air terminaons
must be a minimum of 24 in (61 cm) as shown in
Figure 33
(page
35). In colder climates, this separaon should be increased to
at least 48 in (122 cm).
7. Cut a 5 in (13 cm) diameter hole for four-inch pipe or an 7 in (18
cm) diameter hole for six-inch pipe where the pipe(s) will pass
through the roof.
Note:
Beware of concealed wiring and piping when cung
through the roof.
Table 10. Vent Hole Size
Pipe Size Hole Size
2 in 3 in (7.6 cm)
3 in 4 in (10 cm)
4 in 5 in (12.7 cm)
6 in 7 in (17.7 cm)
8. Suspend the pipe(s) through center of hole using eld-supplied
metal strapping or equivalent support materials as shown in
Figure
31
.
9. Slide a roof boot or equivalent ashing over the pipe, secure the
roof boot or equivalent ashing to the roof (see
Figure 31
), and seal
around the ashing.
10. Install the factory-supplied intake-air and/or vent terminaon(s)
using eld-supplied pipe and one eld-supplied 90° elbow as shown
Venng Installaon
High-Eciency Commercial Gas Water Heaters • 35
in
Figure 31
. The short secon of pipe that connects between the
eld-supplied 90° elbow and the factory-supplied terminaon must
not be excessive in length. The exposed poron of this pipe shall
be no more than 2 in (5 cm). See
Figure 31
.
INTAKE AIR AND/OR VENT
TERMINATION(S) MUST BE A
MINIMUM OF 24 INCHES (60 cm)
ABOVE ANY PARAPET, VERTICAL
WALL OR STRUCTURE WITHIN
10 FEET (3 m) HORIZONTALLY.
VERTICAL TERMINATION(S) FLAT ROOF CLEARANCE
INTAKE AIR AND/OR VENT (EXHAUST)
24 INCHES (60 cm)
MINIMUM HEIGHT ABOVE
IF LESS THAN
10 FEET (3 m)
Figure 32. Vertical Termination(s) Flat Roof Parapet Clearance
11. Return to
Power Vent Installation
(page 31) or
Direct Vent Installation
(page 32) to complete the installaon of the intake-air and/or
vent piping between the terminaon(s) and the water heater.
VERTICAL TERMINATION - DIRECT VENT
STANDARD TERMINATIONS
24 INCHES (61 cm) MINIMUM
48 INCHES (122 cm) IN COLDER CLIMATES
FACTORY SUPPLIED
STANDARD TERMINATIONS
POINTED DOWNWARD
FIELD
SUPPLIED
90° ELBOW
VENT (EXHAUST)
TERMINATION
INTAKE AIR
TERMINATION
FIELD SUPPLIED
PLUMBING
ROOF BOOTS
OR FLASHINGS
MAINTAIN 12” (30 cm)
18” (45 cm) FOR CANADA
MINIMUM CLEARANCE
ABOVE HIGHEST
ANTICIPATED SNOW LEVEL.
Figure 33. Vertical Termination - Direct Vent
HORIZONTAL TERMINATION INSTALLATION
1. Determine the locaon for the terminaon(s).
2. If installing only vent (exhaust) piping in a power-vent conguraon
through a sidewall, ensure that all exterior sidewall clearance
requirements for the terminaon shown in
Figure 62
(page 46),
are being maintained. These clearances, and those cited by local
and naonal codes, must be maintained.
3. If installing both intake-air and vent piping in a direct-vent
conguraon through a sidewall, ensure that all exterior sidewall
clearance requirements for the terminaons shown in
Figure 62
(page 46), for the vent and intake-air termination, are being
maintained. These clearances, and those cited by local and naonal
codes, must be maintained.
4. If installing both an intake-air and vent terminaon in a direct-vent
conguraon through a sidewall, there must be a minimum of 24
in (61 cm) separaon, measured on a vercal center line, between
the intake-air and vent terminaons. See
Figure 34
.
Note:
In colder climates, this separaon should be increased to
at least 48 in(122 cm) between the intake-air and vent
terminaon or any other appliance vent that discharges
moisture-laden air such as clothes dryers. This will reduce
possibility of frost over from side winds blowing exhaust
vapors to the intake-air terminaon and is recommended
for Canadian installaons.
5. If installing both intake-air and vent terminations in a Direct
Vent conguraon through a sidewall, the intake-air and vent
terminaons must be installed at the same elevaon, measured
on horizontal center line. See
Figure 34
.
VENT (EXHAUST)
TERMINATION
INTAKE AIR
TERMINATION
INSTALL ON
ELEVATION
CENTERLINE
24 INCHES (61 cm) MINIMUM
48 INCHES (122 cm) IN COLDER CLIMATES
KEEP INTAKE AND VENT
TERMINATION SCREENS
CLEAR OF DEBRIS
Figure 34. Sidewall Termination - Direct Vent
6. When the intake-air and/or vent piping from mulple water heaters
will terminate at the same locaon through a sidewall, the vent
terminaons can be grouped together in close proximity - 0 in (0
cm) / touching. The intake-air terminaons can also be grouped
together in close proximity - 0 in (0 cm) / touching.
However, the distance between the closest vent and intake-air
terminaons must be a minimum of 24 in (61 cm). In colder
climates, this separaon should be increased to at least 48 in
(122 cm). See
Figure 34
(page 35).
7. Cut a hole where the pipe(s) will pass through the wall. See
Table
10
(page 34)
for the size of the hole needed.
Note:
Beware of concealed wiring and piping when cung
through the wall.
8. Refer to vent hole size table in previous page.
9. Vent Terminaon – exhaust gases of this water heater are less than
140°F (60 C°). In cold climates, water vapor in the exhaust gases will
condense into a cloud of vapor where the vent exits the building.
This vapor can gradually discolor exterior building surfaces. The vent
terminaon should be located where this vapor cloud and potenal
36 • High-Eciency Commercial Gas Water Heaters
Venng Installaon
discoloraon are not a concern. Extending the exposed vent piping
up to a maximum of 6 in (15.2 cm) from the wall helps vapor from
being trapped along a building’s face. To avoid this problem, the
vent can also be terminated vercally through the roof, see
Vertical
Termination Installation
(page 33).
10. Cement the intake-air and/or vent terminaon to the secon(s) of
pipe cut to length in the above step.
11. Slide the included metal wall plate(s) over the pipe(s) to stop
against the intake-air and/or vent terminaon. Place some silicone
caulking (eld-supplied) on the back of the wall plate(s) to secure
it to the wall.
12. Working from outside, slide the pipe and terminaon(s) assembled
in the above steps through the wall. Ensure that the terminaon(s)
is pointed down towards the ground. See
Figure 35
.
INTERIOR WALL EXTERIOR WALL
FROM
WATER
HEATER
COUPLING
METAL PLATES
INSTALL INSIDE
AND/OR OUTSIDE
FACTORY SUPPLIED
STANDARD TERMINATION
POINTED DOWN
TOWARDS THE GROUND
INCREASE EXPOSED VENT
PIPING UP TO A MAXIMUM
OF 6 INCHES (15.2 cm) FROM
WALL TO HELP PREVENT VAPOR
FROM DISCOLORING THE WALL
SURFACE IN COLDER CLIMATES
Figure 35. Sidewall Termination Installation
13. Place a bead of silicone caulking (eld-supplied) around the gap
between the installed pipe(s) and the wall. Apply enough to ll the
gap between the pipe(s) and wall.
14. Press the wall plate ush against the outside wall.
15. Working from the inside, apply enough silicone caulking on the
back of the interior wall plate(s) to hold it in place and slide the
wall plate over the installed pipe(s).
16. Install a coupling to the end of the pipe(s) inside the building. Before
the silicone caulking has me to completely set, go outside the
building and ensure that the terminaon(s) is sll poinng down
towards the ground. See
Figure 35
.
17. Return to
Power Vent Installation
(page 31) or
Direct Vent Installation
(page 32) to complete the installaon of the intake-air and/or
vent piping between the terminaon(s) and the water heater.
POLYPROPYLENE INSTALLATIONS
The water heaters covered by this manual have been approved to be
installed with Polypropylene vent material as shown in
Table 11
and
Table
12
. The approved applicaon of single wall, non-exible, non-concentric
Polypropylene vent material is oered by two specic manufacturers
(Centrotherm ECO Systems and DuraVent Polypropylene). These
listed products must be installed by following the vent manufacturer’s
instrucons. See
Table 6
(page 21)
to determine the maximum pipe
length and maximum number of elbows that can be used.
Insulaon should not be used on Polypropylene venng materials. The
use of insulaon will cause increased vent wall temperatures, which
could result in vent pipe failure.
Use only the adapters and vent system listed in the tables below.
DO
NOT
mix vent systems of dierent types or manufacturers. Failure to
comply could result in severe personal injury, death, or substanal
property damage.
Installaons must comply with applicable naonal, state, and local
codes. For Canadian installaon, Polypropylene vent must be listed
as a
ULC-S636
approved system. If Polypropylene vent is not required
by your local code, you may use either PVC or CPVC pipes for your
water heater, which allow non-metallic venng material installaons.
Polypropylene vent systems do not use cement to connect the pipe
and elbow secons, but use a push together gasket seal method.
Do not aempt to connect Polypropylene with sealant cement. All
vent connecons
MUST
be secured by the vent manufacturer’s joint
connector. The installer must use a specic vent starter adapter at the
ue connecon. The adapter is supplied by the vent manufacturer to
adapt to its vent system.
In order to be in full compliance with
UL-1738
or
ULC-S636
and to meet
the requirements of the water heater manufacturer, you must use the
metal joint-connector rings, available from the Polypropylene vent
manufacturer, to sen the joints of four-inch and six-inch diameter
pipes.
Table 11. M & G Duravent PolyPro Vent System Part Numbers
Nominal
Pipe
Diameter
Flue
Outlet
Adapter
Adapter
Connector
Ring
Connector
90 Degree
Elbow
Vent
Material
Vent Terminal(s)
2” 2PPS-AD PPS-PAC 2PPS-LB 2PPS-E90B 2PPS
2PPS-E45B for
Exhaust;
2PPS-E45B for
Intake
(Direct Vent Only)
3” 3PPS-AD PPS-PAC 3PPS-LB 3PPS-E90B 3PPS
3PPS-E45B for
Exhaust;
3PPS-E45B for
Intake
(Direct Vent Only)
4” 4PPS-AD PPS-PAC 4PPS-LB 4PPS-E90B 4PPS
4PPS-E45B for
Exhaust;
4PPS-E45B for
Intake
(Direct Vent only)
6”
6PPS-
06PVCM-
6PPF
PPS-PACL 6PPS-LBC 6PPS-E90 6PPS
6PPS-E45 for
Exhaust;
6PPS-E45 for
Intake
(Direct Vent only)
Table 12. Centrotherm InnoFlue SW Vent system part numbers
Nominal
Pipe
Diameter
Flue Outlet
Adapter
Adapter
Connector
Ring
Connector
90 Degree
Elbow
Vent
Material
Vent Terminal(s)
2” ISAGL0202 IAFC02 IANS02 ISELL0287 ISVL02
ISELL0245UV for
Exhaust;
ISELL0245UV for
Intake (Direct Vent
only)
3” ISAGL0303 IAFC03 IANS03 ISELL0387 ISVL03
ISELL0345UV for
Exhaust;
ISELL0345UV for
Intake (Direct Vent
only)
4” ISAGL 0404 IAFC04 IANS04 ISEL0487 ISVL04
ISELL0445UV for
Exhaust;
ISELL0445UV for
Intake (Direct Vent
only)
6” ISAGL 0606 IAFC06 IANS06 ISEL0687
Polypro-
pylene
ISELL0645UV for
Exhaust;
ISELL0645UV for
Intake (Direct Vent
only)
AL29-4C
®
VENT INSTALLATIONS
(AL29-4C
®
is a registered trademark of Allegheny Technologies, Inc.)
Venng Installaon
High-Eciency Commercial Gas Water Heaters • 37
The water heaters covered by this manual are approved to be
installed with AL29-4C
®
stainless steel vent material using parts from
the manufacturers listed in
Table 13
and
Table 14
below. These listed
systems must be installed using the vent manufacturer’s instrucons
including their listed clearances to combusble and noncombusble
materials. See
Table 7,
Table 8, and Table 9
(page 30)
for the maximum
and minimum equivalent linear vent lengths and number of elbows
that may be used. However, see
Table 13
and
Table 14
below to nd the
appropriate equivalent linear vent lengths for the AL29-4C
®
elbows.
Note:
The equivalent lengths of the AL29-4C
®
elbows are dierent
than those from smooth walled plasc vents. See
Table 13
and
Table 14
for the correct equivalent linear vent lengths.
Listed vent systems composed of AL29-4C
®
must not mix parts from
the dierent manufacturers. The joints of these products are sealed by
internal gaskets. Do not use any other type of sealant. When assembling
these vent systems, follow the vent manufacturer’s instrucons for
cleaning and lubricang the joints, if required. Each secon must be
locked together using the method supplied by the vent manufacturer.
The water heaters covered by this manual can be installed using the
approved vent terminaons shown in this manual. This means that,
the installer must use the adapter listed in
Table 13
and
Table 14
and a
short piece of PVC pipe to complete the end of the vent system with
an approved terminaon. In Canada, the PVC pipe length must be
listed to
ULC636
.
Table 13. HeatFab Saf–T Vent AL29-4C
®
Vent System Parts
Dia.
Flue
Outlet
Adapter
*Straight
Pipe (3’
Secon)
45°
Elbow
Equivalent
Linear
Length, 45°
Elbow
90°
Elbow
Equivalent
Linear
length, 90°
Elbow
Adapter to
PVC
3”
9301
PVC
9307 9311
5 (178
cm)
9314
10 (305
cm)
9353CPVC
4"
9401
PVC
9407 9411
5 (178
cm)
9414
10 (305
cm)
9454CPVC
6"
9601
PVC
9607 9611
5 (178
cm)
9614
10 (305
cm)
9656CPVC
*Consult vent manufacturer’s catalogue for other available lengths.
Table 14. Duravent FasNSeal AL29-4C® Vent System Parts
Dia.
Flue Outlet
Adapter
*Straight
Pipe (3’
Secon)
45° Elbow
Equiv-
alent
Linear
Length,
45° Elbow
90° elbow
Equiv-
alent
Linear
Length,
90° Elbow
Adapter to
PVC
3” 810005378 FSVL3603 FSELB4503
5 ft
(178 cm)
FSELB9003
10 ft
(305 cm)
810009530
4" 810005545 FSVL3604 FSELB4504
5 ft
(178 cm)
FSELB9004
10 ft (305
cm)
810009529
6" 810005225 FSVL3606 FSELB4506
5 ft
(178 cm)
FSELB9006
10 ft (305
cm)
810005572
*Consult vent manufacturer’s catalogue for other available lengths.
COMMON VENTING
The water heaters covered by this manual may be installed using
a common horizontal direct vent kit. Contact Technical Support for
assistance in ordering common vent kits. See the contact informaon
label on the water heater.
CONCENTRIC TERMINATION INSTALLATION
Concentric terminaons must be ordered separately.
• The 100k - 250k BTU/h models must use the four-inch concentric
terminaon, Part Number: 100111100, for both three-inch and
four-inch vent diameters or the two-inch terminal (100112869)
for two-inch diameter pipe.
• The 251k-500k BTU/h models must use the six-inch concentric
terminaon for both 4” & 6” vent diameters, Part Number:
100113124.
Contact Technical Support for assistance in ordering concentric
terminaons. See the contact informaon label on the water heater.
1. Determine the locaon for the terminaon.
Note:
Roof terminaon is preferred since it is less suscepble
to damage, has reduced risk of intake contaminants, and
vent vapors are less visible.
2. When installing a concentric terminaon vercally through the
roof, ensure that all exterior vercal clearance requirements for
the concentric terminaon shown in
Figure 36
and
Figure 39
(page
39) are being maintained. These clearances and those cited by
local and naonal codes must be maintained.
3. When installing a concentric terminaon vercally through a at
roof, the terminaon’s vent cap must be a minimum of 10 (3
m) away from any parapet, vercal wall, or structure as shown in
Figure 36
.
Note:
If this required distance to a parapet, vercal wall, or
structure cannot be maintained, standard terminaons
must be used. See
Vertical Termination Installation
(page
33).
CONCENTRIC TERMINATION(S)
MUST BE A MINIMUM OF 10 FEET
(3 m) AWAY FROM ANY PARAPET,
VERTICAL WALL OR
STRUCTURE.
VENT PIPE
INTAKE AIR PIPE
Figure 36. Concentric Termination - Flat Roof Parapet Clearance
4. When installing a concentric termination through a sidewall,
ensure that all exterior sidewall clearance requirements for the
terminaon shown in
Figure 62
(page 46) are being maintained.
These clearances and those cited by local and naonal codes must
be maintained.
38 • High-Eciency Commercial Gas Water Heaters
Venng Installaon
5. When installing mulple concentric terminaons vercally through
a roof or horizontally through a sidewall, ensure that the required
clearances between terminations and groupings of multiple
terminaons are maintained. See
Multiple Concentric Termination
Clearances
(page 39)
for more informaon.
6. Cut a 7 in (18 cm) diameter hole for six-inch concentric terminaons
where they will pass through the wall or roof. Cut a 5 in (13 cm)
diameter hole for the four-inch concentric terminal or a 3 in (7.6
cm) hole for the two-inch terminal, where the terminaon will pass
through the wall or roof.
Note:
Beware of concealed wiring and piping when cung
through the wall or roof.
7. When installing mulple concentric terminaons vercally through
the roof in the same locaon, the terminaon caps for all concentric
terminaons must be at the same height measured from ground.
See
Multiple Concentric Termination Clearances
(page 39).
8. Determine if the concentric terminaon will need to be shortened
to accommodate required clearances or to ensure that all vent
caps are at the same height when installing mulple terminaons
vercally through the roof in the same locaon.
See
Figure 37
and
Figure 38
for the minimum lengths allowed for
concentric terminaon.
Note:
When shortening the length of the terminaon, carefully
measure and cut the larger (intake-air) pipe rst. Cut the
same amount of pipe o of the smaller (vent) pipe.
Note:
Lengthening of the Concentric Vent Terminaon is not
permied.
VENT PIPE
INTAKE AIR CONNECTION
VENT CONNECTION
INTAKE AIR PIPE
Y FITTING ASSEMBLY
VENT CAP
VENT PIPE ASSEMBLY
MINIMUM ALLOWABLE LENGTH 25 INCHES (64 cm)
INTAKE AIR PIPE MAY BE SHORTENED
MINIMUM ALLOWABLE LENGTH 12 INCHES (30 cm)
VENT CAP
INTAKE AIR PIPE
Y FITTING
VENT PIPE MAY BE SHORTENED
Figure 37. Concentric Termination Kit - 60/100 Gallon
9. Assemble and install the concentric terminaon. See
Figure 38
,
Figure 39,
and
Figure 40
for these instrucons.
VENT PIPE
INTAKE AIR CONNECTION
VENT CONNECTION - 4 INCH PVC
INTAKE AIR PIPE
Y FITTING ASSEMBLY
VENT CAP
VENT PIPE ASSEMBLY
VENT PIPE IS 4 INCH SDR-26 PIPE
SUPPLIED LENGTH 46.50” (118 cm)
MINIMUM ALLOWABLE LENGTH 16.38” (41.6 cm)
INTAKE AIR PIPE IS 6 INCH SDR-26 PIPE
SUPPLIED LENGTH 25.38” (64.5 cm)
MINIMUM ALLOWABLE LENGTH 12” (30 cm)
VENT CAP
INTAKE AIR PIPE
6” x 6” x 6”
Y FITTING
6” x 4” BUSHING
(FACTORY
INSTALLED)
Figure 38. Concentric Termination Kit - 119 Gallon
10. Cement the Y ng to the larger diameter intake-air pipe.
11. Slide the intake-air pipe and Y ng assembly from inside the
building through the hole cut for the terminaon in the roof or
sidewall. Ensure no foreign materials, such as insulaon, accumulate
inside the assembly.
12. Secure the intake-air Y-ng assembly using eld-supplied metal
strapping or equivalent support materials.
13. On installaons installed through the roof, slide a eld-supplied
plumbing boot or roof ashing over the intake-air Y-ng assembly
and secure it to the roof.
14. Seal around the plumbing boot or roof ashing.
15. Cement the vent cap onto the vent pipe. Alternately a eld-supplied
stainless-steel screw can be used to secure the two components
together when eld disassembly is desired for cleaning. A pilot hole
must be drilled for the screw to prevent damage/cracking of the
vent cap and/or vent pipe.
16. Install the vent cap/vent pipe assembly into the intake-air Y-ng
assembly. Ensure that the small-diameter vent pipe is cemented
and boomed in the Y ng.
17. Connect the intake-air and vent piping from the water heater to
the six-inch concentric terminaon using eld-supplied reducer
couplings as needed. Cement all ngs and pipe in place. Use the
appropriate method for connecng intake-air and vent piping to
the terminaons as follows:
• For two-inch installaons, connect the pipe directly to the
two-inch terminaon.
• For three-inch installaons, connect the pipe directly to
the three-inch terminaon. Do not mix dierent pipe and
terminaon sizes.
• For four-inch pipe installaons, connect the piping to the
concentric terminaon using eld-supplied 4” x 3” reducer
coupling and short secons of three-inch pipe 18 in (45 cm)
or less.
Venng Installaon
High-Eciency Commercial Gas Water Heaters • 39
Do not exceed the maximum equivalent vent length specied
Table 7,
Table 8, and Table 9
(page 30).
18. Return to
Direct Vent Installation
(page 32) to complete the
installaon of the intake-air and vent piping between the concentric
terminaon and the water heater.
NOTE: SECURING STRAP
MUST BE FIELD INSTALLED
TO PREVENT MOVEMENT
OF TERMINATION KIT
MAINTAIN 12” (30 cm)
18” (45 cm) FOR CANADA
MINIMUM CLEARANCE
ABOVE HIGHEST ANTICIPATED
SNOW LEVEL. MAXIMUM OF
24” (60 cm) ABOVE ROOF.
ROOF FLASHING
(field supplied)
STRAP
(field supplied)
VENT
PIPE
INTAKE
AIR PIPE
COMBUSTION
AIR
VENT
Figure 39. Concentric Termination - Vertical Installation
INTAKE AIR PIPE
STRAP
(field supplied)
VENT PIPE
COMBUSTION
AIR
VENT
1 inch(2.54 cm)
MAXIMUM
NOTE: SECURING STRAP MUST BE
FIELD INSTALLED TO PREVENT
MOVEMENT OF TERMINATION KIT
IN SIDEWALL.
Figure 40. Concentric Termination - Sidewall Installation
Multiple Concentric Termination Clearances
When installing mulple concentric terminaons vercally through
a roof or horizontally through a sidewall, ensure that the required
clearances (separaon) between terminaons are maintained. Ensure
mulple terminaons are arranged or grouped as required.
Note:
These clearances must be maintained to prevent the
recirculaon of vent (exhaust) gases to the intake-air. Clearances
are measured between the edges of the concentric terminaon
caps.
When installing mulple concentric terminaons through a roof or
through a sidewall, the clearances shown in
Figure 41
(page 39)
through
Figure 45
(page 40)
must be maintained.
Close Proximity & Standard Clearance
1. The clearance between mulple terminaon caps must be 0 cm (0
in) / touching to a maximum of 2 in (5 cm), dimension A -
Figure
41
, when installing concentric terminaons in close proximity. See
Figure 41
through
Figure 45
.
2. The clearance between mulple terminaon caps must be increased
to a minimum of 24 in (61 cm), dimension B -
Figure 41
, when
installaon in close proximity (above) is not possible. This is the
standard clearance.
A
OR
B
A = 0 - 2 INCHES (0 - 5 cm)
CONCENTRIC
TERMINATION CAPS
END VIEW
TWO CONCENTRIC TERMINATIONS
(THROUGH A ROOF OR SIDEWALL)
B = 24 INCHES (61 cm)
OR GREATER
CLOSE PROXIMITY STANDARD CLEARANCE
Figure 41. Two Concentric Terminations
Three Concentric Terminaons
1. When installing three concentric terminaons through a roof or
through a sidewall, the third terminaon can be installed in close
proximity as indicated by dimension A in
Figure 42
.
2. If close-proximity installaon of the third terminaon is not possible,
the third terminaon can be installed as indicated by dimension B
in
Figure 42
.
A = 0 - 2 INCHES (0 - 5 cm)
CLOSE PROXIMITY
CONCENTRIC
TERMINATION
CAPS END VIEW
THIRD
TERMINATION
THREE CONCENTRIC TERMINATIONS
(THROUGH A ROOF OR SIDEWALL)
A
A B
B = 24 INCHES (61 cm)
OR GREATER
Figure 42. Three Concentric Terminations
Four Concentric Terminaons
1. When installing four concentric terminaons through a roof or
through a sidewall in close proximity, they can be arranged into
stacked rows of two, as shown in
Figure 43,
or lateral rows of two
as shown in
Figure 44
.
2. Four is the maximum number of concentric terminaons that can
be installed in a group where all terminaons are in close proximity
as shown in
Figure 43.
40 • High-Eciency Commercial Gas Water Heaters
Venng Installaon
A
A
A = 0 - 2 INCHES (0 - 5 cm)
CLOSE PROXIMITY
CONCENTRIC
TERMINATION
CAPS END VIEW
FOUR CONCENTRIC TERMINATIONS
(THROUGH A ROOF OR SIDEWALL)
Figure 43. Four Concentric Terminations - Close Proximity
A B
A
FOUR CONCENTRIC TERMINATIONS
(THROUGH A ROOF OR SIDEWALL)
A = 0 - 2 INCHES (0 - 5 cm)
CLOSE PROXIMITY
B = 24 INCHES (61 cm)
OR GREATER
CONCENTRIC
TERMINATION
CAPS END VIEW
Figure 44. Four Concentric Terminations in a Line
Groups Of Terminaons
When installing mulple groups of concentric terminaons through a
roof or through a sidewall in close proximity, they can be installed into
stacked groups of four as shown in
Figure 48
(page 41). Lateral groups
of four as shown in
Figure 45
can be a more convenient installaon
arrangement for mulple groups, depending on available space.
A
A B
A = 0 - 2 INCHES (0 - 5 cm)
CLOSE PROXIMITY
CONCENTRIC
TERMINATION
CAPS END VIEW
EIGHT CONCENTRIC TERMINATIONS
(THROUGH A ROOF OR SIDEWALL)
B = 24 INCHES (61 cm)
OR GREATER BETWEEN
GROUPS OF FOUR
Figure 45. Eight Concentric Terminations
Multiple Concentric Termination Arrangements
The illustrations on this page show some of the installation
arrangements for mulple concentric terminaons that are allowed.
See
Multiple Concentric Termination Clearances
(page 39) for detailed
informaon on clearances and addional arrangement opons.
Note:
When mulple concentric terminaons are installed through a
roof in the same locaon, all terminaon caps must be at the
same height as measured from the ground.
Two Concentric Terminaons
Two concentric terminaons can be installed in close proximity as
shown in
Figure 46
or with standard clearances when this arrangement
is not possible. See
Figure 41
(page 39) for detailed informaon on
clearances. See
Figure 42
(page 39) when installing three concentric
terminaons.
SIDEWALL
ROOF
Figure 46. Two Concentric Terminations - Sidewall and Roof
Four Concentric Terminaons
Four concentric terminaons can be installed in close proximity as
shown in
Figure 47
. See
Figure 43
(page 40)
and
Figure 44
(page 40)
for detailed informaon on clearances and addional arrangement
opons.
Venng Installaon
High-Eciency Commercial Gas Water Heaters • 41
SIDEWALL
ROOF
Figure 47. Four Concentric Terminations - Sidewall and Roof
Eight Concentric Terminaons
Eight concentric terminaons can be installed in two stacked groups
of four, in close proximity, as shown in
Figure 39
. See
Figure 39
(page
39) for detailed informaon on clearances.
Lateral groups of four as shown in
Figure 38
(page 38) can be a more
convenient installaon arrangement for mulple groups depending
on available space.
SIDEWALL
ROOF
Figure 48. Eight Concentric Terminations - Sidewall and Roof
LOW PROFILE VENT INSTALLATION
This water heater is cered for sidewall direct venng with IPEX
System 636 Low-Prole Vent Kit. Follow instrucons below for proper
installaons.
All terminaon kits must be located and installed in accordance with
local building code and
CSA B149.1 Natural Gas and Propane Installation
Code
.
1. Once the proper locaon has been determined, cut two holes in the
wall large enough to accommodate the pipe. Pipe diameters and
distance between hole centers can be found in
Table 15
(page 42).
2. Slide both the intake and exhaust pipes through the holes. Solvent
cement to both pipes to the base of the vent terminaon kit. Follow
the solvent cemenng procedures outlined in the
IPEX System 636
Installation Guide
, which is available on the web www.ipexinc.com.
3. To fasten the base to the wall, use the supplied screws and anchors.
A 3/16 in (5 mm) hole, 1-3/16” (30mm) deep, will need to be drilled
for the anchors. Locate the anchor hole using the base as a template.
4. Screw the Cap to the Base using the supplied screws.
5. Once the vent termination and pipes are secured, the wall
penetraons will need to be sealed from the interior using a PVC-
compable sealant material.
All vent pipes and air inlets must terminate at the same height to
avoid possibility of severe personal injury, death, or substanal
property damage.
6. Operate heater through one heat cycle to ensure combuson-
air and vent pipes are properly connected to concentric vent
terminaon
42 • High-Eciency Commercial Gas Water Heaters
Venng Installaon
Vent Base
V
ent Cap
Air Inlet
Piping
Vent (Exhaust)
Piping
Figure 49. Inlet and Vent Flow in Low Profile Installation
To Heater Intake
Air Connection
From Heater Vent
Pipe Connection
Vent/Air
Termination
12”
Min to
Over-
Hang
12”
Min
Grade or
Snow Line
Possible Orientations
Figure 50. Inlet and Vent Flow in Low Profile Vent Installation
12” Min between Edge of Air Inlet
and Adjacent Vent
(Exhaust) Outlet
Air Inlet
Vent/Air
Termination
Vent (Exhaust)
Figure 51. Multiple Low Profile Vent Clearances
Table 15. Low Prole Terminaon Kits - Dimensions
Kit
Number
IPEX
Part
No. Descripon
Pipe Outside
Diameter
Hole Spacing
(Center to Center)
100086241 196984
2” Flush Mount
Vent Kit
2.375 in (6 cm) 5.63 in (14.3 cm)
100187887 196985
3” Flush Mount
Vent Kit
3.5 in (8.9 cm) 5.63 in (14.3 cm)
100187888 196986
4" Flush Mount
Vent Kit
4.50 in (11.4 cm) 5.63 in (14.3 cm)
100187889 196080
6" Flush Mount
Vent Kit
6.61 in (16.8 cm) 7.63 in (19.4 cm)
Table 16. Each Low Prole Terminaon Kit Contains
Qty Item Descripon
1 Base (two holes)
1 Cap (one hole)
8 Stainless Steel Screws
4 Plasc Anchors
Venng Installaon
High-Eciency Commercial Gas Water Heaters • 43
VENTING ARRANGEMENTS
Figure 52. Power Vent Vertical
Figure 53. Power Vent Horizontal
To drain
Enlarged View of
Direct Vent Air
Intake Moisture
Protection*
Figure 54. Direct Vent Vertical
To drain
Enlarged View of
Direct Vent Air
Intake Moisture
Protection*
Figure 55. Direct Vent Horizontal
To drain
Enlarged View of
Direct Vent Air
Intake Moisture
Protection*
Figure 56. Direct Vent Vertical Vent
Horizontal Intake
To drain
Enlarged View of
Direct Vent Air
Intake Moisture
Protection*
Figure 57. Direct Vent Horizontal Vent
Vertical Intake
*Direct Vent combuson air intake drains are required in certain situaons. See
Direct Vent Air Intake Moisture Protection
(page 33).
44 • High-Eciency Commercial Gas Water Heaters
Venng Installaon
To drain
Enlarged View of
Direct Vent Air
Intake Moisture
Protection*
Figure 58. Direct Vent Vertical Concentric
To drain
Enlarged View of
Direct Vent Air
Intake Moisture
Protection*
Figure 59. Direct Vent Horizontal Concentric
To drain
Enlarged View of
Direct Vent Air
Intake Moisture
Protection*
Figure 60. Direct Vent Horizontal Low-Profile
*Direct Vent combuson air intake drains are required in certain situaons. See
Direct Vent Air Intake Moisture Protection
(page 33).
Venng Installaon
High-Eciency Commercial Gas Water Heaters • 45
SIDEWALL TERMINATION CLEARANCES
Fixed
Closed
Operable
Fixed
closed
Operable
B
V
V
V
V
V
V
V
V
C
B
B
X
A
M
K
Regulator vent outlet
In the event no
regulator is present,
H and I can be
disregarded
.
V
Legend:
= Vent terminal
X
= Air supply inlet
= Area where terminal is not permitted
B
B
J
F
X
B
L
E
D
Inside
corner detail
V
A
G
H
15 ft
I
Figure 61. Sidewall Power Vent Using Outside Air
If local adopted installaon codes specify clearances dierent from those illustrated, then the most stringent clearance shall prevail
Terminaon Clearances for Sidewall Power Vent
Type of Clearance Canadian Installaons
1
US Installaons
2
A Clearance above
grade, veranda, porch,
deck or balcony
12 inches (30 cm) 12 inches (30 cm)
B
Clearance to window
or door that may be
opened
• 6 in (15 cm) for applianc-
es ≤ 10,000 Btuh (3 kW)
• 12 in (30 cm) for appli-
ances > 10,000 Btuh (3
kW) and ≤ 100,000 Btuh
(30 kW),
• 36 in (91 cm) for appli-
ances > 100,000 Btuh
(30 kW)
• 6 in (15 cm) for applianc-
es ≤ 10,000 Btuh (3 kW)
• 9 in (23 cm) for appli-
ances >10,000 Btuh (3
kW) and ≤ 50,000 Btuh
(15 kW)
• 12 in (30 cm) for ap-
pliances > 50,000 Btuh
(15 kW)
C Clearance to perma-
nently closed window
12 inches (30 cm)* 12 inches (30 cm)*
D Vertical clearance to
ventilated soffit locat-
ed above the terminal
within a horizontal
distance of 2 feet (61
cm) from the center
line of the terminal
12 inches (30 cm)* 12 inches (30 cm)*
E Clearance to unventi-
lated soffit
12 inches (30 cm)* 12 inches (30 cm)*
F Clearance to outside
corner
2 feet (60 cm)* 2 feet (60 cm)*
G Clearance to inside
corner
18 inches (45 cm)* 18 inches (45 cm)*
Terminaon Clearances for Sidewall Power Vent
Type of Clearance Canadian Installaons
1
US Installaons
2
H Clearance to each
side of center line ex-
tended above meter/
regulator assembly
3 ft (91 cm) within a height
of 15 ft (4.6 m)
Clearance in accordance
with local installation codes
and the requirements of
the gas supplier
I
Clearance to service
regulator vent outlet
3 ft (91 cm)
Clearance in accordance
with local installation codes
and the requirements of
the gas supplier
J
Clearance to a non
mechanical air supply
inlet into building or
combustion air inlet
to any other appliance
• 6 in (15 cm) for applianc-
es ≤ 10,000 Btuh (3 kW)
• 12 in (30 cm) for appli-
ances > 10,000 Btuh (3
kW) and ≤ 100,000 Btuh
(30 kW)
• 36 in (91 cm) for appli-
ances >100,000 Btuh
(30 kW)
• 6 in (15 cm) for applianc-
es ≤ 10,000 Btuh (3 kW)
• 9 in (23 cm) for appli-
ances >10,000 Btuh (3
kW) and ≤ 50,000 Btuh
(15 kW)
• 12 in (30 cm) for ap-
pliances > 50,000 Btuh
(15 kW)
K Clearance to a
mechanical air supply
inlet
6 feet (1.83 m)
3 feet (91 cm) above if with-
in 10 feet (3 m) horizontally
L
Clearance above
paved sidewalk or
paved driveway locat-
ed on public property
7 feet (2.13 m)†
7 ft (2.13 m) for mechanical
draft systems (Category I
appliances); vents for Cat-
egory II and IV appliances
cannot be located above
public walkways or other
areas where condensate or
vapor can cause a nuisance
or hazard
M Clearance under
veranda, porch, deck,
or balcony
12 inches (30 cm) ‡ 12 inches (30 cm) ‡
1. In accordance with the current
CSA B149.1, Natural Gas and Propane Installation Code
.
2. In accordance with the current
ANSI Z223.1/NFPA 54, National Fuel Gas Code
.
† A vent shall not terminate directly above a sidewalk or paved driveway that is located between two single family dwellings and serves both dwellings where it can cause hazardous frost o
ice accumulaons on adjacent property surfaces.
‡ Permied only if veranda, porch, deck, or balcony is fully open on a minimum of two sides beneath the oor.
* Clearance in accordance with local installaon codes and the requirements of the gas supplier and the manufacturer’s installaon instrucons
46 • High-Eciency Commercial Gas Water Heaters
Venng Installaon
Fixed
Closed
Operable
Fixed
closed
Operable
B
V
V
V
V
V
V
V
V
C
B
B
X
A
M
K
Regulator vent outlet
In the event no
regulator is present,
H and I can be
disregarded
.
V
Legend:
= Vent terminal
X
= Air supply inlet
= Area where terminal is not permitted
B
B
J
F
X
B
L
E
D
Inside
corner detail
V
A
G
H
15 ft
I
Figure 62. Other than Sidewall Power Vent Using Outside Air
Terminaon Clearances for Sidewall Direct Vent
Type of Clearance
Canadian Installaons
1
US Installaons
2
A Clearance above grade,
veranda, porch, deck or
balcony
12 inches (30 cm) 12 inches (30 cm)
B
Clearance to window
or door that may be
opened
• 6 in (15 cm) for applianc-
es ≤ 10,000 Btuh (3 kW)
• 12 in (30 cm) for appli-
ances > 10,000 Btuh (3
kW) and ≤ 100,000 Btuh
(30 kW),
• 36 in (91 cm) for appli-
ances > 100,000 Btuh
(30 kW)
• 4 feet (1.2 m) below or to
side of opening;
• 1 foot (30 cm) above
opening
C Clearance to perma-
nently closed window
6 inches (15 cm)* 6 inches (15 cm)*
D Vertical clearance to
ventilated soffit located
above the terminal
within a horizontal dis-
tance of 2 feet (61 cm)
from the center line of
the terminal
12 inches (30 cm) 12 inches (30 cm)
E Clearance to unventilat-
ed soffit
12 inches (30 cm) 12 inches (30 cm)
F Clearance to outside
corner
2 feet (60 cm)* 2 feet (60 cm)*
G Clearance to inside
corner
18 inches (45 cm)* 18 inches (45 cm)*
Terminaon Clearances for Sidewall Direct Vent
Type of Clearance
Canadian Installaons
1
US Installaons
2
H Clearance to each side
of center line extended
above meter/regulator
assembly
3 ft (91 cm) within a height
15 ft (4.6 m)
Clearance in accordance
with local installation codes
and the requirements of the
gas supplier
I
Clearance to service
regulator vent outlet
3 ft (1.83 m)
Clearance in accordance
with local installation codes
and the requirements of the
gas supplier
J
Clearance to a non
mechanical air supply
inlet into building or
combustion air inlet to
any other appliance
• 6 in (15 cm) for applianc-
es ≤ 10,000 Btuh (3 kW)
• 12 in (30 cm) for appli-
ances > 10,000 Btuh (3
kW) and ≤ 100,000 Btuh
(30 kW)
• 36 in (91 cm) for appli-
ances >100,000 Btuh
(30 kW)
• 4 feet (1.2 m) below or to
side of opening;
• 1 foot (30 cm) above
opening
K Clearance to a mechan-
ical air supply inlet
6 feet (1.83 m)
3 feet (91 cm) above if with-
in 10 feet (3 m) horizontally
L
Clearance above paved
sidewalk or paved
driveway located on
public property
7 feet (2.13 m)†
7 ft (2.13 m) for mechanical
draft systems (Category I
appliances); vents for Cat-
egory II and IV appliances
cannot be located above
public walkways or other
areas where condensate or
vapor can cause a nuisance
or hazard
M Clearance under
veranda, porch, deck,
or balcony
12 inches (30 cm) ‡ 12 inches (30 cm) ‡
1 In accordance with the current
CSA B149.1, Natural Gas and Propane Installation Code.
† A vent shall not terminate directly above a sidewalk or paved driveway that is located between two single family dwellings and serves both dwellings.
Where it can cause hazardous frost or ice accumulaons on adjacent property surfaces.
‡ Permied only if veranda, porch, deck, or balcony is fully open on a minimum of two sides beneath the oor.
* Clearance in accordance with local installaon codes and the requirements of the gas supplier and the manufacturer’s installaon instrucons.
High-Eciency Commercial Gas Water Heaters • 47
INSTALLING THE WATER HEATER
CONDENSATE DRAIN INSTALLATION
Installaon must conform with these instrucons and local building
codes.
Condensate neutralizer kits are available. Contact your distributor or
Service Agency.
Field-supplied materials required for installaon include:
• Approved PVC cement and PVC primer.
• 1/2 inch PVC pipe - minimum length to equal the distance
between the water heater and a suitable building drain.
• 1/2 inch PVC ngs (elbows, couplings and adapters) necessary
to install a condensate drain line between the exhaust/
condensate elbow assembly and a suitable building drain.
• Floor mounted standos to brace the drain line.
Installation Notes
1. The condensate drains from the water heater’s covered by
this instruction have pH levels between 4.3 and 5.0. Install a
commercially available neutralizing kit if required by local codes.
Lower pH levels are acidic. Do not connect a metal condensate
drain line, such as copper pipe, to the water heater for this reason.
2. The eld-installed condensate drain line must not be less than 1/2
inch PVC in size. The condensate line must slope to an open drain.
Do not install an additional trap in the condensate drain piping. Do not
remove, modify or alter the factory condensate trap.
Installation Instructions
1. Ensure that the water heater’s Enable/Disable switch is in the
“Disable” posion.
2. Install a 1/2 inch PVC condensate drain line between the condensate
drain connecon on the exhaust/condensate elbow and a suitable
building drain. The exhaust elbow has a “built in” condensate trap.
Do not install an addional trap in the condensate drain piping.
See
Figure 63
.
3. Terminate the condensate drain piping near the drain. See
Figure
63
(page 47).
Note:
In cold climates it is recommended the condensate drain
be terminated at a suitable drain inside the building.
4. Ensure that the condensate drain line is not elevated above the
condensate drain connecon on the exhaust/condensate elbow.
See
Figure 63
.
5. Brace the condensate drain line with oor mounted standos at
intervals of 3 (1 m).
6. Ensure that the condensate drains freely during start up. See
Start
Up
(page 53).
7. Condensate clean out cap must be on and ght when unit is in
operaon.
CONDENSATE DRAIN
LINE - FIELD INSTALLED
BUILDING
DRAIN
1/2” NPT
CONDENSATE
DRAIN
CONNECTION
CONDENSATE
CLEANOUT
EXHAUST/CONDENSATE
(VENT) ELBOW
PRESSURE PORT
Figure 63. Condensate Drain Installation
LEAK DETECTION MODULE INSTALLATION
The water heaters covered by this manual have a water leak detecon
feature that senses the buildup of water in the vicinity of the appliance
seng o alarm to alert the end user. Please follow installaon
instrucons in included kit.
Note:
Must be installed prior to start up.
Sensor
(Inside Drain Pan)
Drain Pan
Wire Mounts
Connector
Cleanout Cover
Access
Figure 64. Leak Detection Module Installation
48 • High-Eciency Commercial Gas Water Heaters
Installing the Water Heater
SUPPLY GAS LINE INSTALLATION
Contact your local gas ulity company to ensure that adequate gas
service is available and to review applicable installaon codes for
your area.
Be sure that the gas meter has sucient capacity to supply the rated gas
input of the water heater as well as the requirements of all other gas
red equipment supplied by the meter. If the gas meter is undersized,
the gas company will have to install a properly sized gas meter.
• Do not use water heater with any gas other than
the gas shown on the rating label.
• Excessive gas pressure to gas valve can cause
serious injury or death.
• Turn off gas lines during installation.
• Contact a qualified installer or service agency for
installation and service.
⚠
WARNING
Fire and Explosion Hazard
Make sure gas supplied is same type listed on the water heater’s
rang label.
The water heaters covered in this manual are not intended for
operaon at higher than 14.0” W. C. (3.49 kPa) for natural and propane
gas supply pressure. See
Table 5
(page 17). The water heaters covered
in this manual require supply gas regulators to maintain required
supply gas pressure. Exposure to higher gas supply pressure may cause
damage to the gas controls which could result in re or explosion. If
overpressure has occurred such as through improper tesng of gas
lines or malfuncon of the supply system the water heater’s gas valve
must be replaced.
Ensure supply regulator vent lines and the safety vent valves are
protected against blockage. These are components of the gas supply
system, not the water heater. Vent blockage may occur during ice
storms.
It is important to guard against gas valve fouling from contaminants
in the gas ways. Such fouling may cause improper operaon, re or
explosion. If copper supply lines are used they must be internally nned
and cered for gas service.
REGULATED GAS
SUPPLY LINE
MAIN GAS
SHUTOFF VALVE
TEE FITTING
PIPE CAP
SEDIMENT TRAP
Figure 65. Main Gas Shut-Off Valve, Tee Fitting, and Sediment Trap
Ensure that all gas pipe is clean on the inside before installaon. To trap
any dirt or foreign material in the gas supply line a sediment trap must
be installed as shown in
Figure 65
. The sediment trap must be readily
accessible and not subject to freezing condions. Install in accordance
with the recommendaons of the local gas ulity company.
Gas Line Sizing
Minimum required supply gas line sizes are shown in
Table 4
(page
17)
and
Table 5
(page 17). Depending on the developed equivalent
length and/or the number of appliances connected to a common main,
the size of supply gas lines may have to be increased.
Size the supply/main gas line(s) in accordance with
Table 17
(page 48)
and
Table 18
(page 49) . The values given in
Table 17
and
Table 18
are
for straight lengths of iron pipe at 0.5” W. C. (125 Pa) pressure drop,
which is considered normal for low pressure systems.
Note:
Fings such as elbows and tees will add to the pipe pressure
drop.
Schedule 40 Steel or Wrought Iron Pipe is the preferred material for
the gas line of this water heater. It is imperave to follow the sizing
recommendaons in the latest version of the
National Fuel Gas Code
if Corrugated Stainless Steel Tubing (CSST) is used as the gas line for
this water heater.
Table 17. Supply Gas Line Sizing U. S. Units
Length in
Feet
Normal Iron Pipe Sizes (Inches)
Input In Thousands Btu/Hr
1/2” 3/4” 1” 1 1/4” 1 1/2” 2”
10 175 360 680 1400 2100 3960
20 120 250 485 950 1460 2750
30 97 200 375 770 1180 2200
40 82 170 320 660 990 1900
50 73 151 285 580 900 1680
60 66 138 260 530 810 1520
70 61 125 240 490 750 1400
80 57 118 220 460 690 1300
90 53 110 205 430 650 1220
100 50 103 195 400 620 1150
125 44 93 175 360 550 1020
150 40 84 160 325 500 950
175 37 77 145 300 460 850
200 35 72 135 280 430 800
High-Eciency Commercial Gas Water Heaters • 49
Table 18. Supply Gas Line Sizing Metric Units
Length In
Meters
Normal Iron Pipe Sizes (inches)
Input in kW
1/2” 3/4” 1” 1 1/4” 1 1/2” 2”
3.0 51 105 199 410 615 1160
6.1 35 73 142 278 428 805
9.1 28 59 110 225 346 644
12.2 24 50 94 193 290 556
15.2 21 44 83 170 264 492
18.3 19 40 76 155 237 445
21.3 18 37 70 143 220 410
24.4 17 35 64 135 202 381
27.4 16 32 60 126 190 357
30.5 15 30 57 117 182 337
38.1 13 27 51 105 161 299
45.7 12 25 47 95 146 278
53.3 11 23 42 88 135 249
61.0 10 21 40 82 126 234
Gas Line Connection
The water heaters covered by this manual are shipped from the factory
with a supply gas connecon. See
Table 4
(page 17). Connect the
supply gas line to the water heater’s Gas Valve in accordance with all
applicable local and naonal code requirements. See
Figure 66
(page
49).
1. The 60-gallon and 100-gallon gas models require a 3/4” NPT
minimum supply gas line. The 119-gallon natural gas models
require a 1 1/4”NPT minimum supply gas line. See
Gas Line Sizing
for addional informaon.
2. Apply thread sealing compounds (pipe dope/ thread-sealer tape)
sparingly and only to the male threads of the pipe joints. Do not
apply sealing compound to the rst two threads. Use pipe dope or
thread-sealer tape marked as being resistant to the acon of liquid
petroleum (LP/propane) gases.
3. Use only a smooth jaw adjustable wrench (such as a monkey
wrench) as a back up on the body of the Gas Valve when ghtening
the rst pipe nipple into the body of the valve.
Do not
use a standard
pipe wrench (Sllson wrench) with metal tooth jaws as this may
permanently damage the valve.
4. Use a standard pipe wrench (Sllson wrench) as a back up on the
rst pipe nipple installed above when connecng other ngs and
pipe in the supply gas line to prevent Gas Valve on water heater
from twisng during installaon.
5. To prevent damage, care must be taken not to apply too much
torque when connecng the supply gas line to the water heater.
6. Install a sediment trap as shown in
Figure 65
(page 48).
7. Install a Main Gas Shuto valve in the supply gas line as shown in
Figure 65
(page 48).
Note:
If overheang occurs or the gas supply fails to shut o,
turn o the Main Gas Shuto valve to the water heater.
Gas Valve
Supply Gas Pressure Test Port
Gas
Connection
Venturi
Manifold Gas Pressure
Test Port (Non Adjustable)
Combustion Air Inlet
Figure 66. 60 Gallon PX52 - Supply Gas Line Connection
Gas
Valve
Supply Gas Pressure
Test Port
Gas
Connection
Venturi
Manifold Gas Pressure
Test Port (Non Adjustable)
Combustion Air Inlet
Figure 67. 100 Gallon VK - Supply Gas Line Connection
Gas Connection
Manifold Gas Pressure
Test Port (Non Adjustable)
Supply
Gas Test
Port
Figure 68. 119 Gallon - Supply Gas Line Connection
50 • High-Eciency Commercial Gas Water Heaters
Installing the Water Heater
Gas Line Leak Testing
• Use joint compound or thread sealer tape compatible
with propane gas.
• Leak test gas connections
before placing the water heater in operation.
• Disconnect gas piping at main gas shutoff valve before
leak testing.
• Install sediment trap in accordance
with NFPA 54 or CAN/CSA B149.1.
⚠
WARNING
Fire and Explosion Hazard
Any me work is done on the gas supply system perform a leak test
to avoid the possibility of re or explosion.
1. For test pressures exceeding 0.5 psi (3.45 kPa) disconnect the water
heater and its Main Gas Shuto Valve from the gas supply piping
system during tesng. See
Figure 46
(page 40). The gas supply
line must be capped when disconnected from the water heater.
2. For test pressures of 0.5 psi (3.45 kpa) or less, the water heater need
not be disconnected, but must be isolated from the supply gas line
by closing the Main Gas Shuto Valve during tesng.
3. Paint all supply gas line joints and connecons upstream of the
water heater with a with a chloride-free liquid leak detecon
soluon to test for leaks. Bubbles indicate a gas leak. Do not use
matches, candles, ame or other sources of ignion for this purpose.
4. Turn o gas supply and repair any leaks before placing the water
heater in operaon.
Purging
Gas line purging is required with new piping or systems in which air
has entered. Purging should be performed per the current edion of
NFPA 54
the
National Fuel Gas Code
.
ELECTRICAL WIRING
All electrical work must be installed in accordance with the
National
Electrical Code
,
ANSI/NFPA 70
or the
Canadian Electrical Code, CSA C22.1
and local requirements.
When installed, the water heater must be electrically grounded in
accordance with local codes or, in the absence of local codes, with
the
National Electrical Code, ANSI/NFPA 70
or the
Canadian Electrical
Code, CSA C22.1
.
If any of the original wire as supplied with the water heater must be
replaced, replacement harnesses are available through Service Parts.
Dedicated Power Wiring and Breakers
Dedicated power supply wires, ground wiring and dedicated circuit
breakers oen prevent electrical line noise and are required when
installing the water heater.
Note:
This water heater should not be connected to an electrical
supply with a Ground Fault Circuit Interrupter (GFCI) or Arc
Fault Circuit Interrupter (AFCI) with Integral GFCI protecon as
dened in
NFPA 70, CSA C22.1
and
UL 943
.
Power Supply Connections
See the requirements for the
Power Supply
(page 20)
before
connecng power.
The 120 VAC hot wire from the power supply must connect to the
black jumper wire or the “L1” terminal block locaon in the juncon
box and the 120 VAC neutral wire must connect to the white jumper
wire or the “Neutral” terminal block locaon in the juncon box for
correct polarity. See
Figure 69
.
Power supply connecons must be made as follows:
1. Turn o the enable/disable switch to disable heang operaon.
2. Turn o power to the water heater at the breaker that supplies
power to the water heater.
3. Remove the juncon box cover. See
Figure 5, Figure 6,
and
Figure 7
(page 10) for juncon box locaon.
4. Connect the 120 VAC hot wire from the power supply to the black
jumper wire or the terminal block locaon marked “L1” inside of
the juncon box located on top of the water heater. If the black
jumper wire is used, make the connecon inside of the juncon box
with a properly sized wire nut and wrap electrical tape around the
wire nut and wire end. See juncon box
Figure 69
and the wiring
diagram
Figure 84
(page 99),
Figure 85
(page 100), or
Figure 86
(page 101).
5. Connect the 120VAC neutral wire from the power supply to the
white jumper wire or the terminal block locaon marked “Neutral”
inside of the juncon box located on top of the water heater. If
the white jumper wire is used, make the connecon inside of the
juncon box with a properly sized wire nut and wrap electrical
tape around the wire nut and wire end. See
Figure 69
and wiring
diagram
Figure 84
(page 99),
Figure 85
(page 100), or
Figure 86
(page 101)..
Note:
If electrical connecons are made directly to the
terminal block remove the jumper wires before making
connecon.
6. Connect the ground wire from the power supply to the green
jumper wire or the ground terminal locaon inside of the juncon
box located on top of the water heater. If the green jumper wire is
used, make the connecon inside of the juncon box with a properly
sized wire nut and wrap electrical tape around the wire nut and
wire end. See
Figure 69
and wiring diagram
Figure 84
(page 99),
Figure 85
(page 100), or
Figure 86
(page 101)..
7. Replace the juncon box cover when connecons are complete.
Installing the Water Heater
High-Eciency Commercial Gas Water Heaters • 51
Note:
Do not apply power to the water heater before
installaon is complete and the water heater is lled with
water.
Heater Wiring
(factory installed)
Ground Terminal
Jumper Wire
L1
Neutral
Figure 69. Power Supply Connections
Note:
Ensure that the water heater is protected from freezing
temperatures when water heang operaon is disabled.
Damage to the water heater caused by freezing
temperatures is not covered under the limited warranty.
External Enable-Disable Circuit
The water heaters covered in this manual are equipped with an enable
disable circuit for use with eld-supplied supervisory controls such as
me clocks or Building Management Systems. The enable/disable
circuit may be used to disable heang operaon during periods when
the building is unoccupied or there is no demand for hot water. To use
the enable disable circuit it must rst be acvated by selecng “use
External Enable” from the UIM. Field support wiring is then installed
between the water heater’s controls and a set of dry contacts (no
voltage or load) on the eld-supplied external control. See wiring
diagram
Figure 84
(page 99),
Figure 85
(page 100), or
Figure 86
(page 101).
WATER LINE CONNECTIONS
The water piping installaon must conform to these instrucons and to
all local and naonal code authority having jurisdicon. Good pracce
requires that all heavy piping be supported.
Read and observe all requirements in the following secons before
installaon of the water piping begins:
1.
Mixing Valves
(page 21).
2.
Dish-washing Machines
(page 21).
3.
Temperature-Pressure Relief Valve
(page 22).
4.
Closed Water Systems
(page 21)
and
Thermal Expansion
(page
21).
5. For mulple water heater installaons, see
Water Piping Diagrams
(page 102).
Water Piping Diagrams
This manual provides detailed water piping diagrams for typical
methods of applicaon for the water heaters. See
Water Piping Diagrams
(page 102).
The water heater may be installed with or without a separate storage
tank. When used with a separate storage tank, the circulaon may be
either by gravity or by means of a circulang pump. When a circulang
pump is used, it is important to note that the ow rate should be slow
so that there will be a minimum of turbulence inside the water heater
storage tank.
Adjust ow by throling a full port ball valve installed in the circulang
line on the outlet side of the pump. Never throle ow on the sucon
side of a pump. See
Water Piping Diagrams
(page 102).
Note:
In addion to the factory-installed Temperature-Pressure Relief
Valve (T&P valve) on the water heater, each remote storage tank
that may be installed and piped to a water heang appliance
must also have its own properly sized, rated and approved
Temperature-Pressure Relief Valve installed.
Thermometers
Thermometers (not supplied) are installed in the water piping system
as a means of detecng the temperature of the hot water supply at
crical points in the system. Field-supplied thermometers should be
obtained and installed. See
Water Piping Diagrams
(page 102).
Water (potable) Heating And Space Heating
1. All water piping components connected to the water heater that
are for space heang applicaons shall be suitable for use with
potable water.
2. Toxic chemicals, such as those used for boiler treatment, must
NEVER be introduced into this system.
3. The water heaters covered in this manual may never be connected
to any exisng heang system or component(s) previously used
with non-potable water heang appliance.
4. When the system requires water for space heang that exceed
safe temperatures at domesc water xtures a mixing valve must
be installed. See
Mixing Valves
(page 21).
5. These water heaters cannot be used in space heang applicaons
only.
T&P Valve Discharge Pipe
Normal opera�on of the water heater can cause
it to become sufficiently over-heated and/or
over-pressurized that it can explode, resul�ng in
property damage, sever injury, or death.
To avoid this hazard, you must install a properly-
sized temperature-pressure relief valve in opening
provided.
• The temperature-pressure relief valve must
comply with ANSI Z21.22-CSA 4.4 and ASME
code.
• Do not plug, block, or cap the discharge line.
⚠
WARNING
Explosion Hazard
This water heater is provided with a properly rated/sized and
cered combinaon temperature - pressure (T&P) relief valve by
the manufacturer. See
Temperature-Pressure Relief Valve
(page 22)
for informaon on replacement and other requirements.
52 • High-Eciency Commercial Gas Water Heaters
Installing the Water Heater
Property Damage Hazard
While the water heater is in rou�ne opera�on, it can
release hot water from the temperature-pressure relief
valve discharge pipe in quan��es that could cause
damage to the surroundings.
Locate the water heater near an adequate drain and
in an area where water from the temperature-pres-
sure relief valve discharge pipe will not result in
damage to the area or the lower floors of the
structure.
⚠
CAUTION
Install a discharge pipe between the T&P valve discharge opening and
a suitable oor drain. Do not connect discharge piping directly to the
drain unless a 6” (15.2 cm) air gap is provided. To prevent bodily injury,
hazard to life, or property damage, the relief valve must be allowed to
discharge water in adequate quanes should circumstances demand.
If the discharge pipe is not connected to a drain or other suitable
means, the water ow may cause property damage.
T&P Valve Discharge Pipe Requirements:
• Shall not be smaller in size than the outlet pipe size of the valve,
or have any reducing couplings or other restricons.
• Shall not be plugged or blocked.
• Shall not be exposed to freezing temperatures.
• Shall be of material listed for hot water distribuon.
• Shall be installed so as to allow complete drainage of both the
Temperature-Pressure Relief Valve and the discharge pipe.
• Must terminate a maximum of six inches above a oor drain or
external to the building. In cold climates, it is recommended that
the discharge pipe be terminated at an adequate drain inside the
building.
• Shall not have any valve or other obstrucon between the relief
valve and the drain.
High-Eciency Commercial Gas Water Heaters • 53
START UP
PRIOR TO START UP
Installaon and start up of this water heater requires abilies and skills
equivalent to that of a licensed tradesman in the eld involved. See
Qualifications
(page 7).
D
O NOT USE THIS APPLIANCE IF ANY PART HAS BEEN EXPOSED TO
FLOODING OR WATER DAMAGE.
Immediately call a qualied service
agency to inspect the appliance and to make a determinaon on what
steps should be taken next.
If the unit is exposed to the following, do not operate heater unl all
correcve steps have been made by a qualied service agency.
1. External re.
2. Damage.
3. Firing without water.
Light the water heater in accordance with the Lighng and Operaon
Instrucon label on the water heater and in this manual on (page 56).
The water heaters covered by this manual are equipped with an
electronic control system, which automatically sequences the
Combuson Blower, pre- and post-purging of the combuson chamber,
the spark generator, the Gas Valve, Main Burner ignion, and ame
sensing. See
Control System Operation
(page 62)
.
The control system
will lockout aer three unsuccessful ignion aempts.
Before aempng start up, thoroughly study and familiarize yourself
with the exact sequence of operaon. See
Sequence of Operation
(page
80).
Be certain that the water heater is full of water, that air is purged
from the gas and water lines and that there are no leaks in the gas
and water lines. It is recommended to purge air from the furthest
hot water xture preferably at the highest point. Ensure that all inlet
water valves are open.
FILLING THE WATER HEATER
Follow these steps to ll the water heater prior to start up.
1. Close the heater drain valve.
2. Open a nearby hot water faucet to permit the air in the system
to escape.
3. Fully open the cold water inlet valve allowing the piping and water
heater to ll with water.
4. Close the hot water faucet opened in Step 2 as water starts to ow.
5. Follow the steps in
Start Up
(page 53).
INITIAL START UP
At the inial start up of the heater, an inial calibraon roune must
run. This inial calibraon may take up to 15 minutes. During this
inializaon, any burner heat demand will be blocked.
Aer calibraon, the connuous monitoring funcon becomes acve.
This funcon can trigger a new calibraon in case a gas quality change
is detected or there is a manual intervenon by the qualied service
technician.
This inial calibraon can take up to 15 minutes.
Required Test Equipment.
One U-tube manometer, recommended ranges; 0-14” W.C. (0--3.5 kPa)
and 0-35” W.C. (0-8.7 kPa) or pressure gauges.
One digital manometer can be used in place of U-tube manometers
or pressure gauges. Recommended ranges; -20.00 to + 20.00” W.C.
(0-3.5 kPa) resoluon 0.01” W.C. and 0-35” W.C. (0-8.7 kPa) resoluon
0.10” W.C.
Note:
All test equipment must be acclimated to ambient temperature
before calibraon and use.
54 • High-Eciency Commercial Gas Water Heaters
Start Up
GAS CALIBRATION
At the inial start up of the heater, an inial calibraon roune runs
automacally. This inial calibraon may take up to 15 minutes.
During this inializaon, any burner heat demand will be blocked.
After calibration, the continuous monitoring function becomes
acve. This funcon can trigger a new calibraon in case a gas quality
change is detected. Refer to the
Service Handbook
for further service,
troubleshoong and maintenance.
1. Click ‘Conrm’ to proceed with the calibraon.
Please press confirm to start the calibration.
Calibration
CONFIRM
BACK
2. Set the date and me, then click Conrm to connue with the
calibraon.
Calibraon will begin and progress screen will display.
DATE/TIME
MONTH DAY YEAR HOURS MINUTES AM/PM
4
28
2025
/ /
12
53
PM
- :
1 2 3
TAB
4 5 6
7 8 9
0
CONFIRM
CANCEL
3. The calibraon process will begin and show its progress on the
screen.
Note:
Calibraon may take up to 15 minutes.
Calibrating
(May take up to 15 minutes)
Calibration
CONFIRM
BACK
4. When the calibraon is complete, click BACK to return to the home
screen.
Calibration Complete
Calibration
CONFIRM
BACK
Start Up
High-Eciency Commercial Gas Water Heaters • 55
START UP CONDITIONS
Smoke/Odor
It is not uncommon to experience a small amount of smoke and odor
during the inial start-up. This is due to burning o of oil from metal
parts, and will disappear in a short while.
Thermal Expansion
CAUTION
Property Damage Hazard
Avoid water heater damage from pressure fluctua�ons
in closed water systems.
• Fill tank with water before operating.
• Install thermal expansion tank if necessary.
• Do not apply heat to cold water inlet.
• Contact qualified installer or service agency.
Water supply systems may, because of such events as high line
pressure, frequent cut-os, the eects of water hammer among others,
have installed devices such as pressure reducing valves, check valves,
back ow preventers, etc. to control these types of problems. When
these devices are not equipped with an internal by pass, and no other
measures are taken, the devices cause the water system to be closed.
As water is heated, it expands (thermal expansion) and closed systems
do not allow for the expansion of heated water.
The water within the water tank expands as it is heated and increases
the pressure of the water system. If the relieving point of the water
heater’s temperature-pressure relief valve is reached, the valve will
release excess pressure. The temperature-pressure relief valve is
not intended for the constant relief of thermal expansion. This is an
unacceptable condion and must be corrected. It is recommended
that any devices installed which could create a closed system have a
by-pass and/or the system have an expansion tank or device to relieve
the pressure built by thermal expansion in the water system. Expansion
tanks are available for ordering through a local plumbing contractor.
Contact the local water heater supplier or qualied service agency for
assistance in controlling these situaons.
OPERATIONAL CONDITIONS
Do not remove the powered anode rod leaving the tank unprotected.
By doing so, all warranty on the water heater tank is voided.
Having the 120 v power to the water heater turned o for extended
periods of me also leaves the tank unprotected and can void the
warranty.
Air In Hot Water Faucets
Flammable hydrogen gases can form in water pipes.
The hydrogen can explode if it is exposed to flame and
can cause severe injury or death.
Keep all igni�on sources away from faucet when
turning on hot water.
⚠
WARNING
Explosion Hazard
HYDROGEN GAS: Hydrogen gas can be produced in a hot water system
that has not been used for a long period of me (generally two weeks
or more). Hydrogen gas is extremely ammable and explosive. To
prevent the possibility of injury under these condions, we recommend
the hot water faucet, located farthest away, be opened for several
minutes before any electrical appliances which are connected to the
hot water system are used (such as a dishwasher or washing machine).
If hydrogen gas is present, there will probably be an unusual sound
similar to air escaping through the pipe as the hot water faucet is
opened. There must be no smoking or open ame near the faucet at
the me it is open.
START-UP PROCEDURE
1. Using the control system menus, change the Operang Setpoint
to the lowest temperature seng. See
Operating Set-Point and
Differential Adjustment
(page 64) .
2. Turn the water heater’s Enable/Disable switch to the “Disable”
posion.
3. Close the Main Gas Shut O Valve.
4. Wait ve minutes for any residual gas to clear.
5. Connect manometer to the supply gas pressure port on the gas
valve.
On the water heaters covered by this manual there are test ports
for supply and manifold gas pressure readings on the gas valve.
Using a small at p pocket screw driver - open the needle valve
inside the supply gas pressure test port one full turn only (do not
fully remove the needle valve), then turn the needle valve screw
counter-clockwise to open the valve. Slide the manometer sensing
tube over the top of the test port. See
Figure 70
.
6. Slowly open the supply gas isolaon valve.
7. Purge the manometer tubing before taking any readings.
8. Measure and record the supply gas pressure, this is a “stac”
supply gas pressure reading; while the water heater is not ring.
When applicable, adjust the supply gas pressure at the gas supply
regulator for the water heater. See
Supply Gas Pressure Adjustment
(page 58).
Note:
The manometer tubing should be purged before taking any
readings.
Gas Valve
Supply Gas Pressure Test Port
Gas
Connection
Venturi
Manifold Gas Pressure
Test Port (Non Adjustable)
Combustion Air Inlet
Figure 70. 60 Gallon_PX52 - Gas Valve Assembly
56 • High-Eciency Commercial Gas Water Heaters
Start Up
Gas
Valve
Supply Gas Pressure
Test Port
Gas
Connection
Venturi
Manifold Gas Pressure
Test Port (Non Adjustable)
Combustion Air Inlet
Figure 71. 100 Gallon VK - Gas Valve Assembly
Gas Connection
Manifold Gas Pressure
Test Port (Non Adjustable)
Supply
Gas Test
Port
Figure 72. 119 Gallon - Gas Valve Assembly
LIGHTING THE WATER HEATER
The instrucon label below is axed to the water heaters that are covered by this manual at the factory and must be followed when lighng
and operang the water heater.
Start Up
High-Eciency Commercial Gas Water Heaters • 57
FOR YOUR SAFETY READ BEFOR LIGHTING
WARNING: If you do not follow these instructions exactly, a fire or
explosion may result causing property damage, personal injury,
or loss of life.
BEFORE OPERATING: ENTIRE SYSTEM MUST BE FILLED
WITH WATER AND AIR PURGED FROM ALL LINES
This appliance does not have a pilot. It is equipped with
an ignition device which automatically lights the burner.
Do not try to light the burner by hand.
BEFORE OPERATING, smell all around the appliance
area for gas. Be sure to smell next to the floor because
gas is havier than air and will settle to the floor.
A.
B.
“WHAT TO DO IF YOU SMELL GAS”
• Do not try to light the appliance.
• Do no touch any electrical switch; do not use
any telephone in your building.
• Immediately call your gas supplier from a
neighbor’s phone. Follow the gas supplier’s
instructions.
• If you connot reach your gas supplier, call the
fire department.
Use only your hand to push in the control buttons.
Never use tools. If the control buttons will not push
in, don’t try to repair them, call a qualified service
technician. Force or attempted repair may result in
fire or explosion
C.
Do not use this appliance if any part has been under
water. Immediately contact a qualified installer or
service agency to replace a flooded water heater. Do
not attempt to repair the service unit. It must be
replaced.
D.
STANDBY-HOLD
SYSTEM OK
49°C
49°C
SETPOINT
ENABLE/DISABLE
SWITCH
STOP! Read the safety information above
on this label
Set the Enable/Disable switch on the control
panel to the Enable position.
1.
2.
Set the thermostat to the lowest setting.
3.
Set the Enable/Disable switch on the control
panel to the Disable position.
4.
This appliance is equipped with a device which
automatically lights the burner.
DO NOT TRY TO LIGHT THE BURNER BY HAND.
5.
Wait five (5) minutes to clear out any gas.
If you then smell gas, STOP! Follow “B” in the
safety information above on this label. If you don’t
smell gas, go to the next step.
6.
Turn on all electrical power to the appliance.
7.
Set the Enable/Disable switch on the control panel
to the Enable position.
8.
Set the thermostat to the desired setting.
9.
CAUTION: Hotter water increases the risk of
scald injury. Consult the instruction manual
before changing temperature
10.
If the appliance will not operate, follow the instruc-
tions “TO TURN OFF GAS TO APPLIANCE” and
call your technician or gas supplier.
WARNING: TURN OFF ALL ELECTRIC
POWER BEFORE SERVICING.
Set the thermostat to the lowest setting.
1.
Set the Enable/Disable switch on the control
panel to the Disable position.
2.
Turn off all electrical power to the appliance if
service is to be performed.
3.
TO TURN OFF GAS TO APPLIANCE
58 • High-Eciency Commercial Gas Water Heaters
Start Up
SUPPLY GAS PRESSURE ADJUSTMENT
• Do not use water heater with any gas other than
the gas shown on the rating label.
• Excessive gas pressure to gas valve can cause
serious injury or death.
• Turn off gas lines during installation.
• Contact a qualified installer or service agency for
installation and service.
⚠
WARNING
Fire and Explosion Hazard
Supply gas pressure shall be measured while the water heater is not
ring (stac pressure)
and
while the water heater is ring at full capacity
(dynamic pressure).
If the supply gas pressure to the water heater is not between the
required minimum and maximum values given in
Table 5
(page 17)
adjust the supply gas regulator as necessary. Adjust the supply gas
regulator(s) per the regulator manufacturer’s instrucons to achieve
the required “stac” supply gas pressure. The dynamic pressure will
be directly proporonal to the stac pressure. The dynamic pressure
cannot be adjusted directly but is directly proporonal to the stac
pressure.
MULTIPLE APPLIANCE INSTALLATIONS
In mulple water heater installaons or in installaons where the
installed water heater(s) share a common gas supply main with other
gas red appliances; the supply gas pressures shall be measured at
each water heater with all gas red appliances connected to a common
main ring at full capacity.
On mulple water heater installaons the supply gas line regulators
shall be adjusted to provide gas pressure to each water heater within
the minimum and maximum supply pressure requirements listed in
Table 5
(page 17) with all gas red appliances connected to a common
gas main ring at full capacity.
Note:
A pressure drop of more than 1.5” W. C. (0.37 kPa) when the
Main Burner ignites is an indicaon of an inadequate supply of
gas and can lead to ignion failure, rough starts and/or rough
operaon. If a drop of more than 1.5” W. C. (0.37 kPa) in supply
gas pressure occurs when the Main Burner ignites, ensure that
the supply gas lines and regulator(s) are properly sized and
installed. See the requirements for the supply gas line in
Table
4
(page 17)
and
Table 5
(page 17)
and the instructions in
Supply Gas Line Installation
(page 48). See the requirements for
Supply Gas Regulator
(page 20). Ensure that all requirements
and installaon instrucons are maintained.
CHECKING THE FIRING RATE
Follow these instrucons to determine the actual ring rate of the
water heater:
1. Ensure that there are no other gas red appliances connected to
the gas meter ring during this test.
2. Contact the gas supplier to determine the heang value, in Btu per
cubic foot, of the gas supply.
3. Start the water heater and ensure it is ring.
4. Locate the gas meter serving the water heater.
5. Time how long (in seconds) it takes for one cubic foot of gas to be
used while the water heater is ring with a stop watch.
6. Use the formula below to “clock” the gas meter and determine the
actual ring rate of the water heater based on the heang value
(Btu per cubic foot) of the gas supply:
x H = Btu/hr
3600
T
x 1050 = 300,000 Btu/hr (87.9 kW)
3600
12.6
Example:
• 3600 = seconds in one hour.
• T = me, in seconds, to burn one cubic foot of gas.
• H = heang value of gas in Btu per cubic foot.
• Btu/hr = actual ring rate of the water heater.
Note:
1050 Btu per cubic foot is a standard value for natural gas.
Standard propane gas Btu content is 2500 Btu per cubic foot.
Btu values may change in certain areas and at high elevaons.
Check with the local gas ulity company.
TURNING OFF THE GAS SUPPLY
1. Change the Operang Setpoint to the lowest temperature seng.
See
Operating Set-Point and Differential Adjustment
(page 64).
2. When the water heater has completed its shut down sequence and
enters the standby mode, turn the water heater’s Enable/Disable
switch to the “Disable” posion. When in the “Disable” posion
the switch only removes electrical power from the gas valve so that
water heang is disabled. The display, Control board, and other
electrical components will sll be energized and the display will
read “Water Heang Disabled”.
3. Close the Main Gas Shuto Valve. See
Figure 65
(page 48).
Start Up
High-Eciency Commercial Gas Water Heaters • 59
HIGH ALTITUDE INSTALLATIONS
The water heaters covered by this manual are cered for use without
modicaon for altudes up to 10,100 feet.
Modifying the water heater to exceed the firing rate
on the ra�ng label can result in property damage,
personal injury or death.
• Under no circumstances should the input exceed
the rate shown on the water heater’s rating label.
• Over-firing could result in fire or explosion.
• Gas and carbon monoxide detectors are available.
⚠
WARNING
Fire and Explosion Hazard
• Under no circumstances should the input exceed
the rate shown on the water heater’s rating label.
• Overfiring could result in damage to the water
heater and sooting.
• Gas and carbon monoxide detectors are available.
Breathing carbon monoxide can cause brain damage or death. Always
read and understand instruc�on manual.
⚠
WARNING
Breathing Hazard - Carbon Monoxide Gas
Note:
The actual ring rate of the water heater must not exceed
the input rang on the water heater’s rang label under any
circumstances.
Note:
Due to the input rang reducon at high altudes, the output
rating of the water heater is also reduced and should be
compensated for in the sizing of the equipment.
60 • High-Eciency Commercial Gas Water Heaters
TEMPERATURE REGULATION
HIGH TEMPERATURE LIMIT CONTROL
This water heater is equipped with a non adjustable high temperature
limit control.
The high temperature limit control sensors are located inside the Main
Temperature Probe. See
Figure 5, Figure 6,
and
Figure 7
(page 10) for
locaon. The high temperature limit control acvates when the water
temperature reaches an unsafe level and deacvates when the water
temperature falls back to a safe level.
If the high temperature limit control acvates due to abnormally
high water temperatures in the storage tank, the control system
immediately deenergizes the gas valve and ends the current heang
cycle. The control system becomes locked out, disabling further
heang operaon. The control system displays the “HIGH TEMP LIMIT
EXCEEDED” fault message on the LCD screen. It is important that you
contact a Qualied Service Agent to determine the reason for the
high temperature limit control acvaon before reseng the high
temperature limit control. Once the reason has been determined and
corrected, the high temperature limit control can be reset as follows:
If the high temperature limit control acvates, the water temperature
must drop below 185°F (85°C) before the control system can be reset.
Once the water temperature has cooled below this point, turn o the
power supply to the water heater, then turn it on again to reset the
control system.
THERMOSTAT CONTROL
Because of the increased risk from scalding, if you
set the water heater’s gas control knob higher than
120°F (49°C), install thermosta�c point-of-use
mixing valves at each point of use. Due to the
increased risk of scalding, do not set the tempera-
ture of the thermosta�c mixing valves above 120°F
(49°C).
⚠
DANGER
Burn Hazard
Hot water temperatures required for automatic dishwasher and
laundry use can cause scald burns resulting in serious personal
injury and/or death.
Table 19
shows the approximate me-to-burn
relaonship for normal adult skin.
The temperature at which injury occurs varies with the person’s age
and duraon of exposure. The slower response me of children, the
elderly, or disabled persons increases the hazards to them. If anyone
using hot water provided by the water heater being installed ts into
one of these groups or if there is a local code or state law requiring a
certain water temperature at the point of use, then special precauons
must be taken.
The temperature of the water in the water
heater can exceed the thermostat se�ng and
be hot enough to cause burns.
If you choose a higher temperature se�ng,
install thermosta�c mixing valves at each
point-of-use to help avoid scalding.
⚠
WARNING
Burn Hazard
In addition to using the lowest possible temperature setting that satisfies
the demand of the application, a means, such as a thermostatic point-
of-use mixing valve, for example, can be used at the hot water taps used
by these people to reduce the water temperature.
Check State and/or local codes for thermostac point-of-use mixing
valve requirements and installaon pracces.
Never allow small children to use a hot water tap or draw their own
bath water. Never leave a child or disabled person unaended in a
bathtub or shower.
The water heater should be located in an area where the general public
does not have access to set temperatures.
Seng the Operang Setpoint at 120°F will reduce risk of scalds. Some
jurisdicons require sengs at specic lower temperatures.
Table 19. Burn Time at Various Temperatures
Water Temperature
°F (°C)
Time for 1st Degree Burn
(Less Severe Burns)
Time for Permanent Burns
2nd & 3rd Degree
(Most Severe Burns)
110 (43) (Normal shower temp.)
116 (47) (Pain threshold)
116 (47) 35 minutes 45 minutes
122 (50) 1 minute 5 minutes
131 (55) 5 seconds 25 seconds
140 (60) 2 seconds 5 seconds
149 (65) 1 second 2 seconds
154 (68) Instantaneous 1 second
(U.S. Government Memorandum, C.P.S.C., Peter L. Armstrong, Sept. 15, 1978)
The temperature of the water in the water
heater can exceed the thermostat se�ng and
be hot enough to cause burns.
To reduce the risk of unusually hot water
reaching the fixtures in the house, install point
of use thermosta�c mixing valves at each point
of use.
⚠
WARNING
Burn Hazard
The water heaters covered in this manual are equipped with an
electronic control system to regulate the water temperature inside
the storage tank. The control system senses the temperature from
two factory-installed temperature probes: one installed in the top of
the storage tank and the other installed near the boom. See
Figure
5, Figure 6,
and
Figure 7
(page 10) for locaon.
Temperature Regulaon
High-Eciency Commercial Gas Water Heaters • 61
The Operang Setpoint is adjusted to regulate water temperature
inside the storage tank. This is an adjustable user seng in the control
system’s “Temperatures Menu.” This and all control system menus are
accessed through the user interface module (UIM) located on the front
of the water heater. See
Figure 75
(page 63).
The Operang Setpoint is adjustable from 90°F (32°C) to 180°F (82°C).
The factory seng is 120°F (49°C). See
Operating Set-Point and Differential
Adjustment
(page 64) for instrucons on how to adjust the Operang
Setpoint and other user sengs.
Set the Operang Setpoint at the lowest seng which produces an
acceptable hot water supply. This will always provide the most energy
ecient operaon.
FIRING RATE MODULATION
The water heaters covered by this manual are capable of modulang
their ring rate. The controls system monitors the water temperature in
the tank and regulates the ring rate to achieve the target temperature
setpoint. The ring rate is dictated by the hot-water draw, proximity
to the tank temperature and various other temperature limitaons.
HIGH TEMPERATURE APPLICATIONS
Higher operang temperatures cause more wear on all water heaters
and will decrease the life span of the water heater. Consider installing
a small booster water heater for high temperature applicaons, such
as commercial dishwashers, to raise the outlet temperature from the
larger primary water heater to the desired point of use temperature.
BTH250-NAT
HEATING
118°F
120°F
OFF
GAS
O
N
SETPOINT
Figure 73. Tank Temperature Setpoint
62 • High-Eciency Commercial Gas Water Heaters
CONTROL SYSTEM OPERATION
LIMITING THE RISK OF SCALDING
For a variety of reasons, water heaters can produce water that is much
hoer than its temperature seng. Take precauons to prevent this
higher temperature water from reaching the water xtures.
The temperature of the water in the water
heater can exceed the thermostat se�ng and
be hot enough to cause burns.
To reduce the risk of unusually hot water
reaching the fixtures in the house, install point
of use thermosta�c mixing valves at each point
of use.
⚠
WARNING
Burn Hazard
According to a naonal standard,
Performance Requirements for Water
Temperature Limiting Devices (ASSE 1070)
and many local plumbing codes,
the water heater’s gas control valve should not be used as the sole
means to regulate water temperature and avoid scalds.
A properly adjusted thermostac mixing valve at each point of use
allows you to set the tank temperature to a higher seng without
increasing risk of scalds. A higher temperature seng allows the
tank to provide much more hot water and can help provide proper
water temperatures for appliances such as dishwashers and washing
machines.
WI-FI
The water heaters covered in this manual feature a Wi-Fi funconality
that is enabled at the factory. If Wi-Fi is not required for installaon,
you can be disabled it as follows:
1. Go to main menu screen
2. Select iCOMM icon
3. Wi-Fi Status should show “AP Mode” (If not scroll down to “Change
to AP Mode” line item and Enable)
4. Enable the Wi-Fi if it is showing as disabled
5. Using a phone or tablet go to the Wi-Fi sengs and search available
networks
6. In the list of networks, there should be a name that is similar
to “iCOMMNextGenUIM-XXXXXXXX”. This is the website being
broadcast by the display on the water heater. Select this network.
7. Aer selecng the iCOMM network, a separate message may
appear asking for permission to Stay Connected to the selected
network. Select the opon to stay connected. Under the selected
network name, there should be an indication that the Wi-Fi
connected with the above iCOMM network.
8. Open a new Internet browser window on the device.
9. The Internet browser may automacally go to the web address
192.168.0.1. If it doesn’t, type that number into the address bar.
This will bring up a page that looks similar to the following:
10. Find the network name on the le that corresponds to the local
Wi-Fi network, and select the Connect buon to the right of it.
11. If the local network is password protected, a new screen will appear
asking for the password. Enter the password for the local network
and click Connect.
12. A conrmaon message should appear indicang the Connecon
to Wi-Fi was completed.
LOCKOUT FUNCTION
The water heaters covered in this manual feature a lockout funconality
that is disabled at the factory by default. If the lockout funconality
is required by the end user, the inial installer/contractor can access
this funconality and enable it through the UIM. See
(page 72) for
the procedure.
CONTROL SYSTEM OVERVIEW
The water heaters covered in this manual are equipped with an
electronic control system that regulates water temperature inside the
storage tank. Heang cycles and ignion are managed by the control
system. The high temperature limit control sensors, ame sensor,
pressure switches, and temperature probes are monitored by the
control system. The combuson blower, spark ignion transformer, gas
valve and anode rods are all powered by the control system.
The main components of the control system are a user interface module
(UIM), Temperature Regulaon Control (TRC) and combuson safety
control (CSC). The UIM is located on the top front side of the water
heater. The control boards are mounted on top of the water heater
inside a protecve enclosure. This unit is equipped with an Enable/
Disable switch. To operate unit, make sure the switch is set to Enable.
See
Features and Components
(page 9) for locaon of these and all
water heater components.
TRC
CSC
J13
Figure 74. Control System Components
CONTROL SYSTEM NAVIGATION
All operational information and user settings are displayed and
accessed from the UIM. The UIM houses the control system’s LCD
Touch Display (liquid crystal display).
The Home Screen
During normal operaon, the control system displays the Home screen
on the LCD Touch Display, which is the default screen. The control
system returns to the Home screen when there are no acve fault
Control System Operaon
High-Eciency Commercial Gas Water Heaters • 63
or alert condions or when there has been no user input for several
minutes.
• Manufacturer and water heater model informaon displays in
the Title Bar at the top of the Home screen.
• The Operang setpoint is shown in the middle of the Home
screen. This is the temperature at which the control system will
maintain the water inside the storage tank.
• Status is shown in the upper le. The status shows the current
operaonal state of the control system in real me.
• The light green band on the temperature dial shows the
temperature oset.
• The three horizontal lines on the Home screen will allow you to
access sub menus.
• The Home screen also displays animated status icons to convey
operaonal informaon. See
Table 20
for descripons of the
status icons.
The temperature of the water in the water
heater can exceed the thermostat se�ng and
be hot enough to cause burns.
If you choose a higher temperature se�ng,
install thermosta�c mixing valves at each
point-of-use to help avoid scalding.
⚠
WARNING
Burn Hazard
HEATING
118°F
120°F
SET POINT
OFF
GAS
O
N
Touch Display
Status
Icons
Title Bar
Menu:
(Operational Menus
are Multifunctional.)
Help
Figure 75. User Interface Module (UIM) Home Screen
Status Icons
The Status Icons are displayed on the Home screen and convey
operaonal and diagnosc informaon. The icons are described in the
table below. See
Figure 75
(page 63). Ensure that the water heater
is properly grounded. Proper operaon requires an adequate earth
ground. If the water heater is not properly grounded it will cause errors
including Ignion Failure.
Table 20. Status Icons
Icon Description
The Combuson Blower is energized.
OFF
GAS
O
N
The gas valve is being energized.
The control system has sensed ame at the Main Burner
from the ame sensor. See
Sequence of Operation
(page
80) and
Figure 2
(page 9).
The control system has declared a fault condion and
must be inspected/serviced by a Qualied Service Agent.
Fault message details can be viewed in the Current Fault
menu. Heang operaon is disabled (lockout) unl the
condion that caused the fault is corrected. Power to the
water heater must be cycled o and on at the breaker
to reset the control system.
Note:
Cycling power will not reset the control system
if the condion that caused the fault has not
been corrected.
The control system has declared an alert condion
and must be inspected/serviced by a Qualied Service
Agent. The water heater will connue to operate during
an alert condion.
Operating States
The current operaonal state of the water heater is displayed on the
Home screen as the “Status.” The common operaonal states are
described in the table below. See
Figure 75
(page 63).
64 • High-Eciency Commercial Gas Water Heaters
Control System Operaon
Table 21. Operang States
State Description
Uncalibrated The unit is currently uncalibrated and must go through
calibraon before use.
Calibraon The unit is currently going through calibraon procedure.
Standby Heater is waing on a call for heat.
Inializing Inializing heater before regular heang.
Input
Vericaon
The unit has begun a burn cycle and is checking all safety
circuits.
Pre-Purge The unit has begun a spark period to ignite the main
burner.
Ignion The unit has begun a burn cycle and is checking safety
circuits.
Inter-Purge Aer a failure to ignite the burner, the control is aempt-
ing to purge any excess gas from the heater exchanger
before another aempt to light.
Heang The water heater has been properly lit, and the water in
the tank is being heated.
Post-Purge Combuson products are being pushed out of the heater
exchanger aer a successful heang cycle.
System in Fault The water heater control has detected a fault. No further
heang of the water will be done unl reset.
Blocked A condion is prevenng a burn cycle that must clear
before resuming water heang.
Ext Ena External enable/disable switch is acve on unit.
BMS BMS is acve on unit.
Heater Disabled The heater has been disabled and will not heat water.
Control System Menus
From the Home screen pressing “Menu” on the LCD Touch Display will
display the “Main Menu” this is where all control system menus are
located. The table below describes the control system menus.
Table 22. Control System Menus
Menu Description
Setpoint Manager Most commonly accessed menu. Contains the Operat-
ing Setpoint and Dierenal user sengs.
Heater Status This menu displays the current state of all pressure
switches and the high temperature limit control sen-
sors. The on/o status of the Combuson Blower, gas
valve, igniter, ame sensor and other monitored water
heater components are displayed in this menu.
Display Sengs Temperature units (°F or °C), the LCD appearance
(brightness/contrast) and back-light delay user adjust-
able sengs are located in this menu.
Heater Informaon Elapsed me of operaon, total heang cycle me,
heang cycle count, heang on me along with UIM
and control board soware revisions can be viewed in
this menu.
Current Fault Displays any current alert or fault messages.
Fault History This control system menu retains a list of the last nine
(9) fault and alert messages with a me stamp. The
newest event will replace the oldest. Faults will clear
aer 30 days.
Fault Occurrence This control system menu retains a running total of how
many mes each fault condion has occurred since the
water heater was rst installed. The data does not clear
and cannot be reset.
Restore This control system feature allows the user to restore
control system user sengs to their factory default
sengs. Display Sengs preferences ARE NOT changed
when factory defaults are restored.
Help Screens Text based operaonal and user informaon explain-
ing how to change user sengs, navigate the control
system menus and icon descripons.
USER SETTINGS & CONTROL SYSTEM MENUS
Operating Set-Point and Differential Adjustment
The Operang Setpoint is adjustable from 90°F (42°C) to 180°F (82°C).
The factory seng is 120°F (49°C). The Dierenal is adjustable from
2°F (1°C) to 20°F (11°C). The factory seng is 8°F (4°C). These user
sengs are accessed from the Temperatures menu. The following
instrucons will explain how to adjust these sengs and navigate the
control system menus.
When the water temperature sensed by the control system from the
two (main and lower) Temperature Probes reaches the Operang
Setpoint the control system will end the heang cycle. A heang cycle
will be acvated again when the sensed water temperature drops
below the Operang Setpoint minus the Dierenal seng.
The temperature of the water in the water
heater can exceed the thermostat se�ng and
be hot enough to cause burns.
If you choose a higher temperature se�ng,
install thermosta�c mixing valves at each
point-of-use to help avoid scalding.
⚠
WARNING
Burn Hazard
Note:
Lower Dierenal sengs may cause excessive heang cycles
(short-cycling) which can cause premature failure of heater
components. Set the Dierenal at the highest seng which
produces an acceptable hot water supply. Set the Operang
Setpoint to the lowest seng which produces an acceptable
hot water supply for most ecient use.
Control System Operaon
High-Eciency Commercial Gas Water Heaters • 65
Setpoint Manager
From the Setpoint Manager, you can adjust the Dierenal Mode, the
Dierenal, and see the current Tank Temperature.
To change the Operang Set-Point and Dierenal, do the following:
1. From the Home screen, press MENU icon. The “Main Menu” screen
will be displayed.
Note:
The dierenal is indicated by the light green band on the
temperature dial.
BTH250-NAT
HEATING
118°F
120°F
OFF
GAS
O
N
SETPOINT
The Main Menu is where all control system menus are listed. See
Table 22
(page 64) for a complete list and descripon of control
system menus.
2. Press Heater icon to access the Setpoint Manager.
FAULTS
SETTINGS
MAIN MENU
HEATER
3. Use the arrow Buons to change the current seng.
Note:
Higher Temperature sengs increase wear and operang
costs. Set the Operang Setpoint to the lowest seng
which produces an acceptable hot water supply. This will
always provide the most energy ecient operaon and
longer life.
150°F
SETPOINT
SETPOINT MANAGER
MODE:
CANCEL
DIFFERENTIAL
10°F
ENTER
MANUAL
4. Tap “CONFIRM” to save the new seng. Press “CANCEL” to discard
changes and return to the previously saved seng.
150°F
SET POINT
SETPOINT MANAGER
MODE:
CANCEL
DIFFERENTIAL
10°F
ENTER
MANUAL
Setpoint changed:
New Setpoint is 130°F
Please confirm to continue:
CONFIRM CANCEL
66 • High-Eciency Commercial Gas Water Heaters
Control System Operaon
5. To change the dierenal seng: change the mode from automac
to manual, then use the up and down arrows on the dierenal to
change seng. Conrm to keep changes or Press the Cancel buon
to return to the previously saved sengs.
•
Differential Mode
- Operang mode with an Intelligent
Demand Response (IDR). This mode allows the water heater
to reduce preset dierenal to a lower seng so that
the appliance will more rapidly respond to large draws to
maintain water outlet temperature. This mode is enabled
at the factory by default, but can be disabled in the eld if
required.
•
Differential
- Adjustable user seng that changes the tank
temperature dierenal with a range of 2° to 20°F. The
factory seng is 8°F.
•
Tank Temperature
- Non adjustable. Control system sensed
temperature (averaged from main and lower temperature
probes).
These sengs are adjusted in the same way described in
Operating Set-Point and Differential Adjustment
(page 64).
150°F
SETPOINT
SETPOINT MANAGER
MODE:
CANCEL
DIFFERENTIAL
10°F
ENTER
MANUAL
iCOMM Menu
1. From the Home screen, press MENU icon.
The “Main Menu” screen will be displayed.
2. Press the iCOMM icon to access the iCOMM screen.
FAULTS
SETTINGS
MAIN MENU
HEATER
The iCOMM screen displays the following Wi-Fi informaon:
•
Wi-Fi Status
- displays status of Wi-Fi connecon.
•
Ethernet
- displays status of Ethernet connecon.
•
iCOMM Server
- displays status the iCOMM server.
•
Wi-Fi MAC
- displays the Wi-Fi MAC number.
•
Ethernet MAC
- displays the Ethernet MAC number.
•
DSN
- displays the Device Serial Number (DSN). Used for
registraon of the heater.
•
Wi-Fi Strength
- displays Wi-Fi signal strength as a series of
bars.
•
Wi-Fi Strength
- displays Wi-Fi signal strength dBm units.
Wi-Fi
- Wi-Fi funconality is enabled at the factory. In the boom
poron of the menu, the Wi-Fi can be disabled by selecng the
Enabled>
marker and selecng the
Disable
opon. This is the only
item on this screen that can be adjusted. The other items are for
view and informaon purposes only.
Top of Menu
iCOMM
Wi-Fi Status Connected
Ethernet Not Connected
Registration Registered
iCOMM Server Connected
Control System Operaon
High-Eciency Commercial Gas Water Heaters • 67
Bottom of Menu
DSN
AC000W006323619
Wi-Fi Strength
0Bars
Enabled
Wi-Fi
-128dBm
Wi-Fi Strength
iCOMM
Heater Information Menu
1. From the Home screen, press MENU icon.
The “Main Menu” screen will be displayed.
2. From the Main Menu, press the Heater icon to access the Heater
menu.
FAULTS
SETTINGS
MAIN MENU
HEATER
3. Press the Heater Informaon icon from the Heater menu to enter
the Heater Informaon screen.
HEATER
INFORMATION
HEATER
STATUS
SETPOINT
MANAGER
HEATER MENU
68 • High-Eciency Commercial Gas Water Heaters
Control System Operaon
This screen contains non adjustable operaonal informaon.
•
Elapsed Time
- Total accumulated me the control system
(water heater) has been energized.
•
Total Heat Time
- Total accumulated me the control system
has been in the heang operang state; burner run me.
•
Total Cycle Counter
- Total accumulated count of heang
cycles.
•
Ignition Failure Count
– Total accumulated count of ignion
failures.
•
Flame Loss Count
- Total accumulated count of ame losses.
•
TRC Version -
Soware version for TRC board.
•
UIM Version
- Soware version for user interface module.
•
Serial Number
- Serial number of the water heater.
•
Model Number
- Model number of the water heater
•
CSC Version
- Soware version for CSC board.
•
CPAM1 Version
- Soware version for CPAM1.
•
CPAM2 Version
- Soware version for CPAM2.
•
Building Management Version
- Soware version for Building
Management System.
•
Water Valve Control Version -
Soware version for the water
valve control.
•
NANODE Version -
Soware version for NANODE.
Historical data is stored in the Flex Memory Module (FMM). If the
FMM is removed or damaged during servicing, the historical data
will be lost and heater may no longer operate. The FMM should
never be replaced unless directed by Technical Support.
The Elapsed Time, Burner On Time and Cycle Count indicate age,
usage and wear.
If the Cycle Count per day is high (divide cycle count by days to
determine cycles per day) or the cycle duraon is short (determine
burner on me total minutes, divide burner on me total minutes
by cycle count) consider raising the Dierenal seng to avoid
short cycling and excessive component wear. See
Operating Set-
Point and Differential Adjustment
(page 64).
This historical data can also be used to assist facilies managers
in forecasng planned replacement of equipment to help avoid
lengthy and costly hot water supply interrupons.
Elapsed Time 0 Days 0 Hrs 31 Mins 37
Total Heat Time
0 Days 0 Hrs 10 Mins 0 Secs
Yes
External Enable Status
YesUse External Enable
HEATER INFO
Heater Status Menu
1. From the Home screen, press MENU icon.
The “Main Menu” screen will be displayed.
2. From the Main Menu, press the
Heater Information
icon to access
the Heater Informaon screen.
HEATER
INFORMATION
HEATER
STATUS
SETPOINT
MANAGER
HEATER MENU
Control System Operaon
High-Eciency Commercial Gas Water Heaters • 69
The Heater Status menu displays the following informaon:
•
Status
- Indicates whether the heater is Enabled or Disabled.
•
Blocked Inlet PS
- Indicates if the Inlet is blocked.
•
Blocked Outlet PS
- Indicates if the Outlet is blocked.
•
Igniter On
- Indicates if the Igniter is operaonal
•
Gas Valve On
- Indicates if the gas valve is on.
•
Flame Detected
- Indicates if ame is detected.
•
Blower RPM
- Indicates the blower RPMs
•
Main Temperature
- Temperature reading of the main
temperature probe.
•
Lower Temperature
- Temperature reading of the lower
temperature probe.
•
Anode Current
– Current reading of anode
•
Anode Tank Voltage
– Voltage of anode tank
•
Anode Drive Voltage
– Voltage of anode drive
•
Water Valve 1 Status
– Current status of Water Valve 1
•
Water Valve 1 Error
– Error in Water Valve 1
•
Water Valve 2 Status
- Current status of Water Valve 2
•
Water Valve 2 Error
- Error in Water Valve 2
•
Water Valve 3 Status
- Current status of Water Valve 3
•
Water Valve 3 Error
- Error in Water Valve 3
Top of Menu
HEATER STATUS
Status: HEATER DISABLED
Blocked Inlet PS Open
Blocked Outlet PS Open
Igniter Yes
Bottom of Menu
HEATER STATUS
Water Valve 2 Status Yes
Water Valve 2 Error 3 Tries
Water Valve 3 Error 15rpm
Water Valve 3 Status 500rpm
Display Settings Menu
1. From the Home screen, press MENU icon.
The “Main Menu” screen will be displayed.
2. From the Main Menu, press the Sengs icon to access the Sengs
screen.
FAULTS
SETTINGS
MAIN MENU
HEATER
70 • High-Eciency Commercial Gas Water Heaters
Control System Operaon
The Sengs screen contains adjustable display opons for viewing
informaon on the LCD screen.
•
Temperature Units
- Adjustable user seng that changes
temperature units display to Celsius °C or Fahrenheit °F.
•
Back-light Delay
- Adjustable user seng that determines
how long the LCD back light remains illuminated aer a key
has been pressed. Available sengs are; Always O, 10, 30 or
60 seconds and Always On.
•
Brightness
- Adjustable user seng to adjust the LCD screen
contrast between text and background.
• These sengs are adjusted in the same way as described
Operating Set-Point and Differential Adjustment
(page 64).
• Lock Setpoint manager
• Current Date/Time
Temp Units °F
Display Brightness 8
09/09/2020 12:34 AMDate/Time
30 secBacklight
SETTINGS
Current Fault
1. From the Home screen, press MENU icon.
The “Main Menu” screen will be displayed.
2. From the Main Menu, press the Faults icon to access the Fault Menu.
FAULTS
SETTINGS
MAIN MENU
HEATER
3. From the Fault Menu, press the Current Fault or Current Alert icon
to access the Current Fault screen.
FAULT MENU
FAULT
OCCURRENCE
FAULT
HISTORY
CURRENT
FAULT (NONE)
Control System Operaon
High-Eciency Commercial Gas Water Heaters • 71
The Current Fault screen contains the current Fault or Alert error
message. The me the Fault or Alert message occurred appears directly
below. A brief descripon of what causes the parcular Fault or Alert
condion appears below that.
Press the MORE buon for more detailed service informaon and a
list of possible causes for the Fault or Alert condion.
See
Troubleshooting
(page 80) for more detailed informaon and
diagnosc procedures.
If there is no Fault or Alert condion acve this menu will not contain
any informaon; “(none)” will be shown next to Current Fault in the
Fault menu.
CURRENT FAULT
CURRENT FAULT NAME
Occurred:
09/08/2020 12:34 AM
This will be a brief description of the fault. It will be
described in one or two sentences.
MORE
Fault History Menu
1. From the Home screen, press MENU icon.
The “Main Menu” screen will be displayed.
2. From the Main Menu, press the Faults icon to access the Fault Menu.
FAULTS
SETTINGS
MAIN MENU
HEATER
3. From the Fault Menu, press the Fault History icon to access the
Fault History screen.
The Fault History screen contains non adjustable operaonal
informaon.
FAULT MENU
FAULT
OCCURRENCE
FAULT
HISTORY
CURRENT
FAULT (NONE)
The Fault History screen contains a list of the last nine (9) Fault and
Alert messages with a me stamp. The newest event will replace
the oldest. Faults will clear aer 30 days.
Press the Fault to view details for each Fault or Alert message
stored.
FAULT HISTORY
1: High Temp Limit Exceeded (2)
07/13/2020 03:30 AM
2: Upper Temperature Probe Sensing Failure (3)
06/08/2020 04:06 AM
72 • High-Eciency Commercial Gas Water Heaters
Control System Operaon
Fault Occurrence Menu
1. From the Home screen, press MENU icon.
The “Main Menu” screen will be displayed.
2. From the Main Menu, press the Faults icon to access the Fault Menu.
FAULTS
SETTINGS
MAIN MENU
HEATER
3. From the Faults Menu, press the Fault Occurrence icon to access
the Fault Occurrence screen.
The Fault Occurrence screen contains a running total of how many
mes each Fault condion has occurred since the water heater
was rst installed.
Hardware Fault 1
Software Failure 7
0
Software and FMM Key Incompatible
4
Missing Module
Fault Occurrence
Control System Operaon
High-Eciency Commercial Gas Water Heaters • 73
Lockout Function
1. From the Home screen, press MENU icon.
The “Main Menu” screen will be displayed.
2. From the Main Menu, press the Sengs icon to access the Sengs
screen.
3. Use the arrow buons to scroll through the list to the Lock item.
4. Click on the arrow to the right to access the Lock dialog box.
BTH250-NAT
HEATING
118°F
120°F
SETPOINT
OFF
GAS
O
N
30 secBacklight
SETTINGS
Temp Units °F
04/28/2025 12:34 AMDate/Time
Brightness
8
5. Use the arrows in the Lock dialog box to toggle Yes to enable the
lock or No to disable the lock.
Note:
The lock is disabled by default from the factory.
Click Conrm to implement your selecon.
SETTINGS
30 secBacklight
Temp Units °F
04/28/2025 12:34 AMDate/Time
Brightness
8
Lock
No
CONFIRM
CANCEL
6. Press and hold on the lock icon on the Home screen to unlock the
Setpoint sengs
BTH250-NAT
HEATING
118°F
120°F
SETPOINT
OFF
GAS
O
N
74 • High-Eciency Commercial Gas Water Heaters
Control System Operaon
Restore Factory Defaults Function
1. Press and hold on the A. O. Smith logo on the Home screen.
The Service Informaon screen displays
BTH250-NAT
HEATING
118°F
120°F
SETPOINT
OFF
GAS
O
N
2. Select Restore User Defaults on the Service Informaon screen.
SERVICE INFORMATION
Restore User Defaults Display
Access Code
3. Ensure TRC is selected in the list menu, then press the Conrm
buon.
The original factory sengs of the water heater are restored.
SERVICE INFORMATION
Restore User Defaults Display
Access Code
Restore User Defaults
TRC
CONFIRM
CANCEL
Control System Operaon
High-Eciency Commercial Gas Water Heaters • 75
Service Contact Information
The control system has a menu that Installing contractors and/
or service agents can access to enter their contact informaon for
customers. This contact informaon will be displayed with all Fault
and Alert messages.
1. From the Home screen, press the Main Menu icon. The Main Menu
screen displays.
2. From the Main Menu screen, press the Sengs icon.
BTH250-NAT
HEATING
118°F
120°F
OFF
GAS
O
N
SETPOINT
3. Scroll down to the Sengs Menu and select the Current Contact
Info item. The Contact Informaon screen displays.
Temp Units °F
Display Brightness 8
09/09/2020 12:34 AMDate/Time
30 secBacklight
SETTINGS
CONTACT INFORMATION
John Doe
Widgits LLC
123-456-7890
www.widgitsllc.com
4. To edit a contact informaon item, select it and press the Pencil icon.
5. Edit the item using the keyboard. Press the Save Key to save your
data aer each entry.
Note:
You can enable or disable the display of Contact info by eding
the “Show Contact” item on the Sengs Menu.
CONTACT INFORMATION
John Doe
Q W R T YE I O PU
A S F G HD K L ‘J
C V BX MNZ
.,123
SAVE EXIT
76 • High-Eciency Commercial Gas Water Heaters
MAINTENANCE
Water heater maintenance includes periodic tank ushing and cleaning,
and removal of lime scale. The water heater should be inspected and
adjusted to maintain proper combuson. See
Start Up
(page 53).
A periodic inspecon of the venng system should be made. Where
used, water circulang pump(s) should be oiled according to the pump
manufacturers recommendaons.
MAINTENANCE SCHEDULE
Table 23. Maintenance Schedule
Component Operaon Interval Reference
Tank Drain and Flush Every 6 Months See
Maintenance
(page 76)
.
Tank
Lime Scale Removal
(Water Less Than 25
Grains Hard)
Not Required N/A
Tank
Lime Scale Removal
(Water Greater Than
25 Grains Hard)
Annually
See
Lime Scale Removal
(page
77).
Burner Flames Inspection Every 3 Months
See
Burner Flame Inspection
(page 78).
Burner Inspection/Cleaning As Needed
Contact qualified agency or
professional.
Moving Parts Lubrication Not Required N/A
Powered
Anodes
Inspection/Cleaning Annually
See
Anode Rod Maintenance
(page 78).
T&P Valve Test Operation Semi Annually
See
Temperature-Pressure Relief
Valve Test
(page 79).
Vent System Inspection Annually
See
Vent System Maintenance
(page 79).
Condensate
Neutralization
Inspection Annually
See manual for the condensate
neutralization kit.
Condensate
Collection
Cleaning Annually
See
Vent System Maintenance
(page 79).
Precautions
⚠
CAUTION
Safety Hazard
Do not operate the water heater if it has been exposed to or exhibits
the following:
• Exposed to flooding or water damage
• External damage.
• Firing without water.
• Sooting.
Do not operate the water heater until all corrective steps
have been made by a qualified service technician.
Never operate the water heater without rst being certain it is lled
with water and a properly sized and rated Temperature-Pressure Relief
Valve is installed in the relief valve opening on the water heater. See
Temperature-Pressure Relief Valve
(page 22).
• Overheated water can cause water tank explosion.
• A properly sized temperature and pressure relief
valve must be installed in the opening provided.
⚠
WARNING
Explosion Hazard
If overheang occurs or the gas supply fails to shut o, turn o the
Main Gas Shuto valve. See
Figure 65
(page 48).
DRAINING AND FLUSHING
It is recommended that the water heater storage tank be drained and
ushed every 6 months to reduce sediment buildup. The water heater
should be drained if being shut down during freezing temperatures.
See
Features and Components
(page 9) for the locaon of the water
heater components described below.
⚠
DANGER
Burn Hazard
The discharge water from the drain valve is hot enough
to cause burns.
Keep your hands clear of the drain valve discharge
outlet.
Draining the Water Heater Storage Tank
1. Turn the Enable/Disable switch located on the front of the heater
to the Disabled posion.
2. Turn o the electrical supply to the water heater.
3. Turn o the gas supply at the Main Gas Shuto Valve if the water
heater is going to be shut down for an extended period.
4. Ensure that the cold water inlet valve is open.
5. Open a nearby hot water faucet and let the water run unl the
water is no longer hot.
6. Connect a hose to the water heater drain valve and terminate it to
an adequate drain.
7. Close the cold water inlet valve.
8. Open the water heater drain valve and allow all the water to drain
from the storage tank.
9. Close the water heater drain valve when all water in the storage
tank has drained.
10. Close the hot water faucet opened in Step 4.
11. If the water heater is going to be shut down for an extended period,
the drain valve should be le open.
Flushing the Water Heater Storage Tank
1. Turn the Enable/Disable switch located on the front of the heater
to the Disabled posion.
2. Turn o the electrical supply to the water heater.
3. Ensure that the cold water inlet valve is open.
4. Open a nearby hot water faucet and let the water run unl the
water is no longer hot. Then close the hot water faucet.
5. Connect a hose to the drain valve and terminate it to an adequate
drain.
Maintenance
High-Eciency Commercial Gas Water Heaters • 77
6. Ensure that the drain hose is secured before and during the enre
flushing procedure. Flushing is performed with system water
pressure applied to the water heater.
7. Open the water heater drain valve to ush the storage tank.
8. Flush the water heater storage tank to remove sediment and allow
the water to ow unl it runs clean.
9. Close the water heater drain valve when ushing is completed.
10. Remove the drain hose.
11. Fill the water heater. See
Filling The Water Heater
(page 53).
12. Turn on the electrical supply to place the water heater back in
operaon.
13. Allow the water heater to complete several heang cycles to ensure
it is operang properly.
SEDIMENT REMOVAL
Waterborne impuries consist of the parcles of soil and sand which
sele out and form a layer of sediment on the boom of the tank.
For convenience, sediment removal and lime scale removal should be
performed at the same me.
LIME SCALE REMOVAL
When water is heated dissolved minerals in the water such as calcium
and magnesium carbonate (lime scale) become less soluble. As the
water temperature rises these minerals will precipitate or “fall out”
of soluon.
The amount of lime scale released from water is in direct proporon
to water temperature and usage. The higher the water temperature
or water usage, the more lime deposits are dropped out of the water.
Water hardness also affects lime scale accumulation. With the
temperature and usage being the same, hard water will release more
lime scale than soer water.
Lime scale reduces heang eciency as it accumulates inside a water
heater. Heang transfer surfaces become coated with lime scale
deposits which increases fuel costs to operate the water heater. Lime
scale deposits can also cause rumbling and pounding noises as air
molecules trapped in the lime scale escape when heated. Lime scale
accumulaon also reduces the life span of water heaters. For these
reasons a regular schedule for deliming should be set up.
The depth of lime accumulaon in the boom of the water heater
should be measured periodically. Inspect by removing the clean-out
cover once every 6 months at rst. Deliming maintenance should then
be performed based on the me it takes for 1 inch (2.5 cm) of lime to
accumulate in the boom of the water heater.
Sediment and lime scale removal may be accomplished manually
through the clean-out opening furnished on the water heater. See
Figure 76
.
TANK
CLEANOUT
OPENING
CLEANOUT
COVER
CLEANOUT
GASKET
CLEANOUT
ACCESS PANEL
Figure 76. Clean-out Access
Manual Lime Scale Removal
Note:
Contact Technical Support for assistance in ordering a new
clean-out gasket. See the contact informaon label on the
water heater. Have the new gasket available before removing
the clean-out cover.
The clean-out opening is shown in
Figure 76
. To remove lime scale
manually through the clean-out opening proceed as follows:
1. Turn o the electrical supply to the water heater.
2. The water heater must be drained. See
Draining and Flushing
(page
76). Follow the instrucons on how to drain the water heater.
3. Remove outer clean-out access panel from lower side of the water
heater jacket.
4. Remove the clean-out cover from clean-out opening.
5. Remove lime, scale and/or sediment using care not to damage the
glass-lining.
6. Install a new clean-out gasket if required.
7. Reinstall the clean-out cover. Be sure to draw plate up ght by
ghtening screws securely.
8. Close the water heater drain valve.
9. Fill the water heater. See
Filling The Water Heater
(page 53).
10. Turn on the electrical supply to place the water heater back in
operaon. See
Start Up
(page 53).
11. Allow the water heater to complete several heang cycles to ensure
it is operang properly.
12. Check for water leakage.
13. Reinstall the clean-out access panel.
Chemical Lime Scale Removal
To dissolve and remove more stubborn lime scale deposits, white
vinegar should be used. Hydrochloric base acids must not be used to
delime the water heaters covered in this manual.
78 • High-Eciency Commercial Gas Water Heaters
Maintenance
BURNER FLAME INSPECTION
Check main burner every three months for proper ame characteriscs.
You can see the burner ame through the sight glass on top of the
burner plate. To access the sight glass, you must remove the plasc
cover.
Sight
Glass
Air Intake Connection
Figure 77. Location of Sight Glass
The main burner should display the following characteriscs:
• Provide complete combuson of gas.
• Cause rapid ignion and carry over of ame across enre burner.
• Give reasonably quiet operaon during inial ignion, operaon
and exncon.
• Cause no excessive liing of ame from burner ports. See
Figure
78
.
Figure 78. Normal and Abnormal Burner Flames
If the preceding burner characteriscs are not evident, check for
accumulaon of lint or other foreign material that restricts or blocks
the air intake ng or air intake terminal.
To ensure connued good performance, keep the area around the
water heater clean and free from lint and debris. Sweep the oor
around the water heater regularly. This will reduce the dust and dirt
which can enter the burner and heat exchanger, causing improper
combuson and soong.
If the air intake ng and air intake terminal are clear and the burner
connues to exhibit abnormal ames, contact a qualied service
agency or have a qualied service professional inspect and clean the
burner.
ANODE ROD MAINTENANCE
CAUTION
Property Damage Hazard
Operating the water heater with depleted or
malfunctioning anodes can damage the water
heater.
Annual inspection and replacement of the anode
rod is required.
The water heaters covered in this manual are factory equipped with
powered anode rods mounted in the top of the unit. The anode rods
are of a permanent design and do not need replacing unless damaged,
however, inspecon and cleaning should be performed once a year.
To inspect the powered anode, do the following:
1. Turn o electrical supply and gas supply to the water heater.
2. Shut o the water supply and open a nearby hot water faucet to
depressurize the water tank.
3. Drain approximately 5 gallons of water from tank. See
Draining
and Flushing
(page 76)
for proper procedures. Close drain valve.
4. Remove the wiring connecon on the top of the powered anode.
5. Remove the powered anode by loosening the 3/4” NPT bushing
that forms the top of the anodes.
6. Remove the enre anode rod from the water heater for inspecon.
• If undamaged and in working order, clean the anode rod with
a so cloth and reinstall.
• If the anode needs to be replaced, obtain a new anode rod.
Apply thread-sealer
®
tape or an approved pipe sealant on the
threads before installing the new powered anode rod.
Whether re-installing or replacing the powered anode rod, check
for any leaks and immediately correct if found.
7. Turn on water supply and open nearby hot water faucet to purge
air from water system.
8. Rell the water heater following the instrucons for
Filling The Water
Heater
(page 53).
9. Restart the water heater as directed in this manual.
DRAIN VALVE AND ACCESS PANELS
The water heaters covered in this manual are equipped with a drain
valve. See
Features and Components
(page 9) for locaon. The water
heaters covered in this manual are also equipped with a clean-out
opening for sediment and lime scale removal. See
Figure 76
(page 77).
Maintenance
High-Eciency Commercial Gas Water Heaters • 79
TEMPERATURE-PRESSURE RELIEF VALVE TEST
⚠
DANGER
Burn Hazard
The discharge water from the temperature-pressure
relief valve is hot enough to cause burns.
Keep clear of the temperature-pressure relief valve
discharge outlet.
It is recommended that the Temperature-Pressure Relief Valve should
be checked to ensure that it is in operang condion every 6 months.
When checking the Temperature-Pressure Relief Valve operaon,
make sure that (1) no one is in front of or around the outlet of the
Temperature-Pressure Relief Valve discharge line, and (2) that the water
discharge will not cause any property damage, as the water may be
extremely hot. Use care when operang valve as the valve may be hot.
To check the relief valve, li the lever at the end of the valve several
mes. See
Figure 79
. The valve should seat properly and operate freely.
If aer manually operang the valve, it fails to completely reset and
connues to release water, immediately close the cold water inlet to
the water heater and drain the water heater. See
Draining and Flushing
(page 76). Replace the Temperature-Pressure Relief Valve with a
properly rated/sized new one. See
Temperature-Pressure Relief Valve
(page 22) for instrucons on replacement.
Figure 79. Testing the T&P Relief Valve
If the Temperature-Pressure Relief Valve on the water heater weeps or
discharges periodically, this may be due to thermal expansion.
Note:
Excessive water pressure is the most common cause of
Temperature-Pressure Relief Valve leakage. Excessive water
system pressure is most oen caused by “thermal expansion”
in a “closed system.” See
Closed Water Systems
(page 21)
and
Thermal Expansion
(page 21). The Temperature-Pressure
Relief Valve is not intended for the constant relief of thermal
expansion.
Temperature-Pressure Relief Valve leakage due to pressure build up in
a closed system that does not have a thermal expansion tank installed
is not covered under the limited warranty. Thermal expansion tanks
must be installed on all closed water systems.
Do not plug the Temperature-Pressure Relief Valve opening. This can
cause property damage, serious injury or death.
Normal opera�on of the water heater can cause
it to become sufficiently over-heated and/or
over-pressurized that it can explode, resul�ng in
property damage, sever injury, or death.
To avoid this hazard, you must install a properly-
sized temperature-pressure relief valve in opening
provided.
• The temperature-pressure relief valve must
comply with ANSI Z21.22-CSA 4.4 and ASME
code.
• Do not plug, block, or cap the discharge line.
⚠
WARNING
Explosion Hazard
VENT SYSTEM MAINTENANCE
Examine the vent system once a year. Points of inspecon are as
follows:
1. Check for obstrucons and/or deterioraon of the intake-air and/
or vent piping and the intake-air and vent terminaons. Replace
immediately where needed.
2. The debris screens in the intake-air and vent terminaons should
be should be cleaned of foreign material and soot. See
Figure 34
(page 35).
Note:
Do not reach inside the vent terminaon when the heater
is in operaon.
3. Check all vent system connecons for leakage and repair or reseal
as necessary.
80 • High-Eciency Commercial Gas Water Heaters
TROUBLESHOOTING
INSTALLATION CHECKLIST
The list below represents some of the most critical installation
requirements that, when overlooked, oen result in operaonal
problems, down me and needless parts replacement. This is not a
complete list. Before performing any troubleshoong procedures use
the list below to check for installaon errors.
Note:
Costs to correct installaon errors are not covered under the
limited warranty. Ensure that all installaon requirements and
instrucons in this manual have been maintained and followed.
Water Heater Location
1. Ensure proper clearances to combusbles are maintained and
there is sucient room to service the water heater. See
Clearance
to Combustible Materials
(page 18).
2. Ensure that the area is free of corrosive elements and ammable
materials. See the instrucons in
Contaminated Air
(page 24).
Venting
3. Ensure that the intake-air and/or vent (exhaust) piping is the correct
size for the installed length. See
Venting Requirements
(page 29).
4. Ensure that the maximum equivalent length of pipe has not been
exceeded for the intake-air and/or vent pipe. See
Table 7,
Table 8,
and Table 9
(page 30).
5. Ensure that the maximum number of elbows has not been exceeded
in the intake-air and/or vent pipe. See
Venting Requirements
(page
29).
6. Ensure that the intake-air screen is removed from the intake-air
connecon on the water heater when installing the water heater
in a Direct Vent conguraon. See
Figure 30
(page 33).
7. Ensure that all exterior clearances for the intake-air, vent,
concentric, and low profile terminations are maintained. See
Vertical Termination Installation
(page 33),
Horizontal Termination
Installation
(page 35),
Low Profile Vent Installation
(page 41).
These clearances and those cited by local and naonal codes must
be maintained.
Gas Supply And Piping
8. Ensure a supply gas regulator has been installed for each water
heater.
9. Ensure that the supply gas line to each water heater meets the
minimum supply gas line size requirements. See the requirements
for the supply gas line in
Table 4
(page 17)
and
Table 5
(page 17)
and the instrucons in
Supply Gas Line Installation
(page 48).
Condensate Drain
10. Ensure that the condensate drain is properly connected to the
exhaust elbow on the water heater with a water trap to prevent
vent gases from escaping into the installed space and draining freely
to a suitable oor drain. See
Figure 15
(page 23)
and
Condensate
Drain Installation
(page 47).
Electrical Connections
11. Ensure that the power supply is on a dedicated circuit and
connecons to the water heater are polarity correct. See the
requirements for the
Power Supply
(page 20) and
Electrical Wiring
(page 50).
12. Ensure that the water heater is properly grounded. Flame sensing
requires an adequate earth ground. If the water heater is not
properly grounded it will cause Ignion Failure.
SEQUENCE OF OPERATION
Read the Sequence of Operaon below before aempng to correct
any operaonal problems. See
Features and Components
(page 9)
for the locaon of various water heater components described below.
See
Sequence of Operation
(page 80).
1. When the control system is rst powered, during boot up, it will
display water heater model informaon during inializaon. Aer
a few moments the control system LCD which is part of the user
interface module (UIM) will display the default screen known as
the Home screen.
2. If the control system determines that the actual water temperature
inside the tank is below the programmed Operang Setpoint minus
the Dierenal seng, a heang cycle is acvated.
3. The control system then performs selected diagnosc system
checks. This includes conrming the blocked exhaust, blocked
intake and high temperature limit control sensors are not acvated.
4. If all diagnosc checks are successfully passed, the control system
energizes the Combuson Blower for prepurge.
5. The control system energizes the spark ignion control.
6. The control system energizes the Gas Valve allowing gas to ow to
the Main Burner.
7. The control system monitors the ame sensor to conrm a ame
is present at the Main Burner. If a ame is not veried during the
ignion trial period the control system will try for ignion up to
two more mes. If ame can not be veried aer three trials for
ignion, the control system will lockout and display the “Ignion
Failure” fault message.
8. If a ame is veried, the control system will deenergize the Spark
Ignion Control and enter the heang mode where it will connue
heang the water unl the Operang Setpoint is reached. At this
point, the control system will deenergize the Gas Valve and enter
the post-purge cycle.
9. The water heaters covered by this manual are capable of modulang
their ring rate. The ring rate is dictated by the hot water draw
and various other temperature limitaons.
10. The Combuson Blower will run for the duraon of the post-purge
cycle to purge the water heater of all combuson gases. When
the post-purge cycle is complete, the blower is deenergized and
will coast to a stop.
11. The control system now enters the standby mode while connuing
to monitor the internal storage tank water temperature and the
state of other system devices. If the tank temperature drops below
Troubleshoong
High-Eciency Commercial Gas Water Heaters • 81
the Operang Setpoint minus the Dierenal seng, the control
will automacally return to Step 2 and repeat the operang cycle.
YES NO
Water is heated to
set point
Gas Valve
de-energized
Inter-Purge cycle
Gas Valve
de-energized
Retries up to
two more times
Post-Purge cycle
Control System
Locks Out
“Ignition Failure”
Fault Message
is displayed
Water heater goes
into standby mode
If tank temperature drops below Operating Set Point minus
Differential setting a heating cycle is activated
Spark Ignition Control is energized.
Gas Valve is energized
gas flows to Main Burner
Is flame sensed at the Main Burner?
(control system monitors the flame sensor)
Control System Locks Out
Displays Fault Messages
NO
Combustion Blower is energized
Pre-Purge cycle
Control System performs diagnostic checks
• Normal State of all pressure switches and high-tempera-
ture limit control are checked
• Pressure switches and high-temperature limit control are
verified inactive
Sequence is shown with Enable/Disable Switch in the Enable position
Figure 80. Sequence of Operation
82 • High-Eciency Commercial Gas Water Heaters
Troubleshoong
OPERATIONAL PROBLEMS
Failure to follow these instrucons and safety
messages could result in death or serious injury.
Read and understand this instrucon manual and the
safety messages herein before installing, operang or
servicing this water heater.
This manual must remain with the water heater.
⚠
WARNING
Safety Hazard
This secon of the manual is intended to be an aid in correcng
common operaonal problems, it is not all inclusive. The installer may
be able to observe and correct certain problems which might arise
when the water heater is rst put into operaon or when it is re-red
aer a prolonged shutdown. However, only qualied service agents, as
dened in
Qualifications
(page 7), using appropriate test equipment,
should perform any service procedures on the water heater.
Note:
Contact Technical Support for assistance in locang a qualied
service agent in your area. See the contact informaon label
on the water heater.
Installation Errors
Operaonal problems on new installaons are oen the result of
installaon requirements that have been overlooked rather than failed
components. Rough starng and rough operaon are oen caused by
undersized supply gas lines and/or the absence of a supply gas regulator
at the water heater.
Prior to performing any operaonal checks, inspect the water heater
installaon to ensure that all installaon requirements and instrucons
have been maintained and followed. See
Installation Checklist
(page
80).
Note:
Costs to correct installaon errors are not covered under the
limited warranty.
Rough Starting-Rough Operation
• Do not use water heater with any gas other than
the gas shown on the rating label.
• Excessive gas pressure to gas valve can cause
serious injury or death.
• Turn off gas lines during installation.
• Contact a qualified installer or service agency for
installation and service.
⚠
WARNING
Fire and Explosion Hazard
• Undersized supply gas line (low volume of supply gas). See
the requirements for the supply gas line in
Table 4
(page 17)
and
Table 5
(page 17) and the instrucons in
Supply Gas Line
Installation
(page 48).
• Supply gas regulator is not installed per installaon requirements
(errac gas supply volume/pressures). See
Supply Gas Regulator
(page 20).
• Excessive supply gas pressure. See
Table 5
(page 17) and
Supply
Gas Regulator
(page 20).
• Vent (exhaust) gas recirculaon at the vent and intake-air
pipe terminaons on direct vent installaons. See
Direct Vent
Installation
(page 32).
• Excessive equivalent lengths of intake-air and/or vent (exhaust)
piping installed. See
Venting Requirements
(page 29).
• Debris clogging/blocking the intake-air screen(s). See
Figure 29
(page 33) and
Figure 34
(page 35).
• Debris clogging/blocking the Main Burner. See
Figure 2
(page
9).
Momentary Ignition
Burn Hazard
• The combus�on chamber and burner
sleeve and housing become very hot
during opera�on.
• Do not reach into the burner housing or
combus�on chamber if the water heater is
s�ll hot.
• Allow the water heater to cool and always
use gloves when handling the main burner.
⚠
CAUTION
If the Main Burner ignites momentarily but does not sustain ignion
allow the water heater to try to ignite up to two more mes unl control
system locks out and the Ignion Failure Fault message is displayed
on the control system’s LCD. If the water heater is experiencing rough
starts. See
Rough Starting-Rough Operation
on this page. For momentary
ignion problems without rough starng check the following:
• Undersized supply gas line (low volume of supply gas). See
the requirements for the supply gas line in
Table 4
(page 17)
and
Table 5
(page 17) and the instrucons in
Supply Gas Line
Installation
(page 48).
• Supply gas regulator is not installed per installaon requirements
(errac gas supply volume/pressures). See
Supply Gas Regulator
(page 20).
• See the list of possible causes and things to check and repair for
the Ignion Failure Fault message in
Fault and Alert Conditions
(page 84).
• Debris clogging/blocking the intake-air screen(s). See
Figure 29
(page 33) and
Figure 34
(page 35).
• Debris clogging/blocking the Main Burner
Figure 2
(page 9).
Troubleshoong
High-Eciency Commercial Gas Water Heaters • 83
Not Enough Or No Hot Water
• No power to the water heater, check breaker or fuses.
• Enable/Disable switch in “Disabled” posion. Set to “Enable” to
allow unit to operate.
• Hot water supply valve(s) to xtures closed.
• Operang Setpoint is set too low, Dierenal seng is set too
high. See
Control System Operation
(page 62).
• Tank Probe Oset is causing the heang cycles to terminate
prematurely. See
Setpoint Manager
(page 65).
• The heang capacity of the water heater has been exceeded, the
water heater is unable to meet demand.
• Colder incoming water temperature lengthening the me
required to heat water to desired temperature.
• Hot water piping leaks, open faucets, water heater drain valve
leaking or open.
• Sediment or lime scale accumulaon may be aecng water
heater operaon. See
Maintenance
(page 76) for sediment and
lime scale removal procedures.
• Water heater not ring at full input rang. See
Checking the Firing
Rate
(page 58).
Note:
The water heaters covered by this manual are capable of
modulang their ring rate. The ring rate is dictated by the
hot water draw and various other temperature limitaons.
Water Is Too Hot
• Operang Setpoint is set too high. See
Operating Set-Point and
Differential Adjustment
(page 64).
• If installed check Thermostac Mixing Valve sengs.
• Tank Probe Oset seng improperly set. See
Setpoint Manager
(page 65).
• Lime build-up on temperature probes. Inspect and clean.
• Improper water piping. See
Water Piping Diagrams
(page 102).
Noisy Operation
• Sediment or lime scale accumulaons can cause rumbling and
pounding noises during heang cycles. See
Maintenance
(page
76)
for sediment and lime scale removal procedures.
• Normal operang noise of electrical components; Combuson
Blower, transformer hum, relay contact closure.
Water Leakage Is Suspected
• Ensure that the water heater drain valve is ghtly closed.
• Check clean-out opening for leaks. See
Figure 8
through
Figure 11
(page 14).
• Check inlet/outlet water connecons and system piping.
• Check the Temperature-Pressure Relief Valve.
• Excessive water temperature.
• Excessive water pressure.
• Defecve Temperature-Pressure Relief Valve.
Note:
Excessive water pressure is the most common cause of
Temperature-Pressure Relief Valve leakage. Excessive water
system pressure is most oen caused by “thermal expansion”
in a “closed system.” See
Closed Water Systems
(page 21)
and
Thermal Expansion
(page 21). The Temperature-Pressure
Relief Valve is not intended for the constant relief of thermal
expansion.
Temperature-Pressure Relief Valve leakage due to pressure build up in
a closed system that does not have a thermal expansion tank installed
is not covered under the limited warranty. Thermal expansion tanks
must be installed on all closed water systems.
REPLACEMENT PARTS
Replacement parts may be ordered from the manufacturer, authorized
service agencies or distributors. When ordering parts be sure to have
the complete water heater Model Number, Serial Number and Series
Number available. This informaon can be found on the rang label
axed to the water heater.
See the parts list included with the water heater from the factory for
more informaon or contact Technical Support for assistance. See the
contact informaon label on the water heater.
RESETTING CONTROL SYSTEM LOCKOUTS
To reset the control system from a lockout condion; turn the electrical
power supply o for approximately 20 seconds and then back on. Keep
in mind; if the condion that caused the Fault has not been corrected,
the control system will remain in a lockout condion.
DIAGNOSTIC CHECKS
Servicing this water heater exposes you to
electrified components that can cause severe
injury or death if you touch them.
• Turn off power at the branch circuit breaker
serving the water heater before performing any
service.
• Label all wires prior to disconnecting when
performing service. Wiring errors can cause
improper and dangerous operation.
• Verify proper operation after servicing.
⚠
WARNING
Electrical Shock Hazard
The following secon,
Fault and Alert Conditions
(page 84), lists some
of the messages the control system will display on the LCD when there
are operaonal problems. This is not a complete list. Along with each
of the Fault and Alert messages described there will be a list of possible
causes and things to check and repair.
Only qualified service agents, as defined in
Qualifications
(page
7), using appropriate test equipment, should perform any service
procedures on the water heater.
84 • High-Eciency Commercial Gas Water Heaters
Troubleshoong
Note:
If you are not qualied and licensed or cered as required by
the authority having jurisdicon to perform a given task do not
aempt to perform any of the diagnosc or service procedures
described in the following secon.
If you do not understand the instrucons in the following secon do
not aempt to perform any procedures.
Contact Technical Support for assistance in locang a qualied service
agent in your area. See the contact informaon label on the water
heater.
Jumping out control circuits or components can
result in property damage, personal injury or death.
• Service should only be performed by a qualified
service technician using proper test equipment.
• Altering the water heater controls and/or wiring in
any way could result in permanent damage to the
controls or water heater and is not covered under
the limited warranty.
• Any bypass or alteration of the water heater
controls and/or wiring will result in voiding the
appl
iance warranty.
⚠
WARNING
Safety Hazard
FAULT AND ALERT CONDITIONS
Fault Conditions
When the control system shows a Fault condion it will display a Fault
message on the control system’s UIM with an exclamaon “!” mark.
The control system will lockout and disable heang operaon. To
reset the current fault, toggle the Enable/Disable switch on the front
of the heater from enable to disable, and then back to enable. If the
condion that caused the fault has not been resolved the fault will
reappear. The water heater must be serviced by a qualied service
agent before operaon can be restored.
Alert Conditions
When the control system declares an Alert condion it will display an
Alert message on the control system’s LCD with a queson “?” mark.
The water heater will connue to operate during an Alert condion
but the water heater must be serviced by a qualied service agent as
soon as possible.
Verify the power to the water heater is turned off before
performing any service procedures. The Enable /Disable switch
on front panel disables the gas valve. Electrical supply must be
turned off at circuit breaker serving water heater.
Fault and Alert Messages
Contact Technical Support for further assistance or to locate a qualied service agent in your area. See the contact-informaon label on the
water heater.
Fault and Alert Messages
FAULT CODE Possible Causes - Check/Repair Displayed Fault/Alert Message
2
Data Error Code:
(3, 30) NTC A short
(3, 31) NTC A open
(3, 32) NTC B short
(3, 33) NTC B open
(3,1001) NTC C open
(3,1002) NTC C short
(3,1018) NTC drift
High Temp Limit Exceeded
The water heater is shut down due to high tank temperature.
The water temperature in the tank has exceeded the high
temperature limit.
1. Use a thermometer at a hot water xture to conrm the
actual water temperature. If temperature is below 180˚
reset water heater.
2. If problem connues, contact technical support or refer
to the service handbook for further instrucons.
CURRENT FAULT
High Temp Limit Exceeded
Occurred:
04/28/2025 12:34 AM
The water heater is shut down due to high
tank temperature.
MORE
3
Data Error Code:
30;31;
32;33
Main Temperature Probe Failure
The indicated temperature probe might be shorted or open.
The control system has detected an issue with the main
temperature probe.
1. Ensure the wire connecons for the main temp probe
are clean and secure.
2. Ensure the wire harness for the main temp probe is free
from damages.
3. If the problem connues, contact technical support or
refer to the service handbook for further instrucons.
Note:
If there are both main and lower temperature probes,
the Main Temperature probe is the main temperature
probe.
CURRENT FAULT
Main Temperature Probe Failure
Occurred:
04/28/2025 12:34 AM
The indicated temperature probe might be
shorted or open.
MORE
Troubleshoong
High-Eciency Commercial Gas Water Heaters • 85
Fault and Alert Messages
FAULT CODE Possible Causes - Check/Repair Displayed Fault/Alert Message
4
Data Error Code:
(4,1006) NTC open
(4,1007) NTC short
Lower Temperature Probe Failure
The indicated temperature probe might be shorted or open.
The control system has detected an issue with the lower
temperature probe.
1. Ensure the wire connecons for the lower temp probe
are clean and secure.
2. Ensure the wire harness for the lower temp probe is free
from damages.
3. If the problem connues, contact technical support or
refer to the service handbook for further instrucons.
CURRENT FAULT
CURRENT FAULT
Lower Temperature Probe Failure
Occurred:
04/28/2025 12:34 AM
The indicated temperature probe might be
shorted or open.
MORE
5
Data Error Code:
(3,10xx) where xx =
5,9,13 or 17
Software Failure
Internal control failures are detected on TRC. Cycle power to
the water heater.
The controls system has detected a soware issue.
1. Cycle the main power supply to the water heater
by turning o the breaker/disconnect, then wait
approximately 30 seconds and turn main power supply
back on.
2. If problem connues, contact Technical Support or refer
to the service handbook for further instrucons.
CURRENT FAULT
Software Failure
Occurred:
04/28/2020 12:34 AM
Internal control failures are detected on
TRC. Cycle power to the water heater.
MORE
6
(6,10xx) where xx =
4, 8, 12 or 16
OR
(6,80xx) where xx
= 1-10
Hardware Failure
Internal control failures are detected on the TRC. Cycle power
to the water heater.
The controls system has detected a hardware issue.
1. Cycle the main power supply to the water heater
by turning o the breaker/disconnect, then wait
approximately 30 seconds and turn main power supply
back on.
2. If problem connues, contact Technical Support or refer
to the service handbook for further instrucons.
CURRENT FAULT
Hardware Failure
Occurred:
04/28/2025 12:34 AM
Internal control failures are detected on the
TRC. Cycle power to the water heater.
MORE
9
Data Error Code: 22
Power Supply Fault
The Control System is detecng a problem with the incoming
power supply.
1. Cycle the main power supply to the heater by turning
o the breaker/disconnect, then wait approximately 30
seconds and turn main power supply back on.
2. If problem connues, contact technical support or refer
to the service handbook for further instrucons.
CURRENT FAULT
Power Supply Fault
Occurred:
04/28/2025 12:34 AM
The Control System is detecting a problem
with the incoming power supply.
MORE
86 • High-Eciency Commercial Gas Water Heaters
Troubleshoong
Fault and Alert Messages
FAULT CODE Possible Causes - Check/Repair Displayed Fault/Alert Message
20
Data Error Code:
(20,0)
Communication Failure
Communicaons between the display and the TRC is lost.
The control system has lost communicaons with UIM.
1. Cycle the main power supply to the heater by turning
o the breaker/disconnect, then wait approximately 30
seconds and turn main power supply back on.
2. Inspect the communicaon cable between the UIM and
the TRC to ensure the cable is not damaged and the
connecons are clean and secure.
3. If problem connues, contact technical support, or refer
to the service handbook for further instrucons.
CURRENT FAULT
Communication Failure
Occurred:
04/28/2025 12:34 AM
Communications between the display and
the TRC is lost.
MORE
25
Data Error Code:
(4,1010) NTC open
(4,1011) NTC short
Flue Gas Temperature Probe Failure
The ue gas temperature probe might be shorted or open.
The control system has detected an issue with the ue gas
temperature probe.
1. Cycle the main power supply to the heater by turning
o the breaker/disconnect, then wait approximately 30
seconds and turn main power supply back on.
2. If problem connues, contact technical support for
further instrucons.
CURRENT FAULT
Flue Gas Temperature
Probe Failure
Occurred:
04/28/2025 12:34 AM
The flue gas temperature probe might be
shorted or open.
MORE
26
Data Error Code:
(4,1014) NTC open
(4,1015) NTC short
Recirc Temperature Probe Failure
The recirculaon temperature probe might be shorted or
open.
The control system has detected an issue with the recirc
temperature probe.
1. Cycle the main power supply to the heater by turning
o the breaker/disconnect, then wait approximately 30
seconds and turn main power supply back on.
2. If problem connues, contact technical support for
further instrucons.
CURRENT FAULT
Recirc Temperature
Probe Failure
Occurred:
04/28/2025 12:34 AM
The recirculation temperature probe might
be shorted or open.
MORE
Troubleshoong
High-Eciency Commercial Gas Water Heaters • 87
Fault and Alert Messages
FAULT CODE Possible Causes - Check/Repair Displayed Fault/Alert Message
31
Data Error Code:
(31,7002) or
(31, 7003) or
(31, 7004)
Water Leak Detected
A water leak or other water-present condition is being
detected. Check for a leak or other water problem at the
water sensor.
The control system has detected a leak near the heater.
1. Inspect the area around the heater for signs of moisture.
2. Inspect all threaded ngs connected to the water
heater for signs of moisture.
3. Inspect the exhaust elbow connecon to the heater for
signs of moisture.
4. Inspect the clean-out cover for signs of moisture.
5. Using litmus strips for pH tesng to idenfy if the
moisture is condensate or water from the tank.
6. Condensaon from the exhaust will be highly acidic.
7. If problem connues, contact technical support for
further instrucons.
CURRENT FAULT
Water Leak Detected
Occurred:
04/28/2025 12:34 AM
A water leak or other water-present
condition is being detected. Check for a leak
or other water problem at the water sensor.
MORE
32
Data Error Code:
(32, 7001)
Leak Sensor Disconnected
The leak sensor is no longer being detected by the controller.
The control system has detected that the leak detector has
been disconnected.
1. Ensure the leak detector is securely connected to the
water heater.
2. Ensure the leak detector harness is securely connected
to the TRC at terminal J6 pins 1 and 11.
3. If problem connues, contact technical support for
further instrucons.
CURRENT FAULT
Leak Sensor Disconnected
Occurred:
04/28/2025 12:34 AM
The leak sensor is no longer being detected
by the controller.
MORE
33
Data Error Code:
(33, 60x7) where
x = 0 is on TRC-1000
board anode circuit.
x = 1 is CPAM 1,
x = 2 is CPAM 2 etc.
Anode Shorted
The powered anode is shorted to earth ground or to the tank.
The Control System has detected that the anode rod has
shortage to the tank.
1. Inspect anode wire connecon for corrosion, moisture,
or other contaminates.
2. Ensure wire connecon on both ends is secure.
3. Ensure anode wire harness is not damaged.
4. If problem connues, contact technical support for
further instrucons.
CURRENT FAULT
Anode Shorted
Occurred:
04/28/2025 12:34 AM
The powered anode is shorted to earth
ground or to the tank.
MORE
88 • High-Eciency Commercial Gas Water Heaters
Troubleshoong
Fault and Alert Messages
FAULT CODE Possible Causes - Check/Repair Displayed Fault/Alert Message
34
Data Error Code:
(34, 60x4) where
x = 0 is on TRC-1000
board anode circuit.
x = 1 is CPAM 1,
x = 2 is CPAM 2 etc.
No Water
No water is detected by the powered anode.
The Control System is not detecng water in the tank.
1. Ensure there is water in the tank by following Fill the
Tank Instrucons found in the installaon manual.
2. Inspect anode wire connecon for corrosion, moisture,
or other contaminates.
3. Ensure wire connecon on both ends is secure.
4. Ensure anode wire harness is not damaged.
5. If problem connues, contact technical support for
further instrucons.
CURRENT FAULT
No Water
Occurred:
04/28/2025 12:34 AM
No water is detected by the powered anode.
MORE
36
Data Error Code: 244
(36, 2440x)
x = 1 to 9 are reason
codes.
Weak Flame Signal
The Combuson Safety Control (CSC) is detecng low-ame
generated current.
The control system has detected a weak ame signal
1. Ensure that the ame sensor wire harness is free of
damages
2. Ensure that the ame sensor wire connecon on both
ends is secure and free of contaminates
3. Remove ame sensor and inspect for contaminates or
damages in ceramic insulator
4. Clean ame sensor rod with steel wool
5. If the problem connues, contact technical support, or
refer to the service handbook for further instrucons
CURRENT FAULT
Weak Flame Signal
Occurred:
04/28/2025 12:34 AM
The Combustion Safety Control (CSC) is
detecting low-flame generated current.
MORE
37
Data Error Code:
2, 130
(37, 2)
Or
(37, 130)
Flame Sensor Error
The control system has detected a ame sensor error.
The ame-sense rod is detecng a ame signal when the gas
valve is supposed to be o.
The control system has detected a ame sensor error.
1. Ensure that the ame sensor wire harness is free of
damages.
2. Ensure that the ame sensor wire connecon on both
ends is secure and free of contaminates.
3. Remove ame sensor and inspect for contaminates or
damages in ceramic insulator.
4. Clean ame sensor rod with steel wool.
5. If the problem connues, contact technical support, or
refer to the service handbook for further instrucons.
CURRENT FAULT
Flame Sensor Sensing Error
Occurred:
04/28/2025 12:34 AM
The control system has detected a flame
sensor error.
MORE
Troubleshoong
High-Eciency Commercial Gas Water Heaters • 89
Fault and Alert Messages
FAULT CODE Possible Causes - Check/Repair Displayed Fault/Alert Message
38
(Resideo 129, 147,
241)
or 38
Data Error Code:
(38, 129) or
(38, 147) or
(38, 241) or
(38, 38)
Ignition Failure
The control system failed to sense a ame signal during the
ignion sequence.
The control system failed to sense a ame signal during the
ignion sequence
1. Verify that the gas supply, venng, and intake air
pipes are installed according to the instrucon manual
provided with the water heater.
2. If the problem connues, contact technical support, or
refer to the service handbook for further instrucons.
CURRENT FAULTCURRENT FAULT
CURRENT FAULT
Ignition Failure
Occurred:
04/28/2025 12:34 AM
The control system failed to sense a flame
signal during the ignition sequence.
MORE
41
Data Error Code:
(41, 1003)
High Temperature Warning
The main temperature probe exceeds 190°F.
The water temperature in the tank has exceeded the high
temperature warning temperature. The warning will reset
when tank temperature drops below 180°F.
1. Reset the water heater by toggling the Enable/Disable
switch to disable and back to enable.
2. If the problem connues, use a thermometer at a hot
water xture to conrm the water temperature.
3. If the problem connues, contact technical support or
refer to the service handbook for further instrucons.
CURRENT FAULT
CURRENT FAULT
CURRENT FAULT
Temp High Limit
Occurred:
04/28/2025 12:34 AM
The primary temperature exceeds the
high-limit setpoint.
MORE
42
Clock Not Set
Clock (me and date) are not set.
Check the iComm connecon (if equipped) and reconnect for
automac calendar updates.
The control system recognized that the clock is not set.
1. Refer to the installaon manual for instrucons on how
to set the clock.
2. If the problem connues, contact technical support for
further instrucons.
CURRENT FAULT
CURRENT FAULT
CURRENT FAULT
Clock Not Set
Occurred:
09/08/2020 12:34 AM
Clock (time and date) are not set.
MORE
90 • High-Eciency Commercial Gas Water Heaters
Troubleshoong
Fault and Alert Messages
FAULT CODE Possible Causes - Check/Repair Displayed Fault/Alert Message
201
Data Error Code: 71
(201, 71)
Blocked Air Intake
There is a restricon in the air intake. Check the intake pipe
and terminaon for blockage.
The control system has detected a blockage in the intake air
pipe.
1. Ensure that the intake air pipe installed according to the
manufacturer’s installaon manual.
2. Ensure that all horizontal pipe runs are properly sloped
to prevent moisture from accumulang and restricng
air ow.
3. Inspect the inside of the intake air pipe from the
connecon at the blower, all the way to the outside
terminaon for restricons.
4. Inspect the plasc sensing tube to the blocked intake air
pressure switch to ensure there are no restricons.
5. Ensure the blocked intake air pressure switch wires are
free from damages and contaminates.
6. Ensure wire connecons are secure and free from
contaminates.
7. If problem connues, contact technical support, or refer
to the service handbook for further instrucons.
CURRENT FAULTCURRENT FAULT
CURRENT FAULT
Blocked Air Intake
Occurred:
04/28/2025 12:34 AM
There is a restriction in the air intake. Check
the intake pipe and termination for
blockage.
MORE
202
Data Error Code: 70
(202, 70)
Blocked Exhaust
There is a restricon in exhaust pipe. Check exhaust pipe and
terminaon for blockage.
The control system has detected a blockage in the exhaust
vent pipe.
1. Ensure that the exhaust vent pipe installed according to
the manufacturer’s installaon manual.
2. Ensure that all horizontal pipe runs are properly sloped
to prevent moisture from accumulang and restricng
air ow.
3. Inspect the inside of the exhaust vent pipe from the
water heater connecon all the way to the outside
terminaon for restricons.
4. Inspect the plasc sensing tube to the blocked exhaust
pressure switch to ensure there are no restricons.
5. Ensure the blocked exhaust pressure switch wires are
free from damages and contaminates.
6. Ensure wire connecons are secure and free from
contaminates.
7. If problem connues, contact technical support, or refer
to the service handbook for further instrucons.
CURRENT FAULT
Blocked Exhaust
Occurred:
04/28/2025 12:34 AM
There is a restriction in exhaust pipe. Check
exhaust pipe and termination for blockage.
MORE
Troubleshoong
High-Eciency Commercial Gas Water Heaters • 91
Fault and Alert Messages
FAULT CODE Possible Causes - Check/Repair Displayed Fault/Alert Message
205
Data Error Code:
(205,200x)
Where:
x =2 if the key is
uninitialized
x=3 if key
configuration is
corrupt.
Software and FMM Incompatible
The TRC version is older than the TRC version stored in key.
The control system has detected a device that is incompable
1. Contact Technical Support for further instrucons.
CURRENT FAULT
Software and FMM Key Incompatible
Occurred:
04/28/2025 12:34 AM
The TRC version is older than the TRC
version stored in key.
MORE
206
Data Error Code:
(206, 2011)
CPAM Disconnected
Communicaon with the anode module has been lost.
The control system has detected that the CPAM is disconnected
1. Ensure CPAM is powered
2. Ensure wire connecons are secure and free of
contaminates
3. Ensure wire harness is free of damages
4. If problem connues, contact technical support or refer
to the service handbook for further instrucons
CURRENT FAULT
CPAM Disconnected
Occurred:
04/28/2025 12:34 AM
Communication with the anode module has
been lost.
MORE
207
Data Error Code:
(207, 35)
CSC Disconnected
The control system has detected that the CSC is disconnected.
1. Ensure the communicaon cable is securely connected
between the TRC on terminal J4 and the CSC on terminal
X10.
2. If problem connue, contact technical support for
further instrucons.
CURRENT FAULT
CSC Disconnected
Occurred:
04/28/2025 12:34 AM
Communication with the anode module has
been lost.
MORE
209
Data Error Code:
(209, 2013)
Water Valve Module Disconnected
Communicaon with the water valve module has been lost.
The control system has detected that the Valve Module is
disconnected.
1. Ensure Valve module is powered.
2. Ensure wire connecons are secure and free of
contaminates.
3. Ensure wire harness is free of damages.
4. If problem connues, contact technical support or refer
to the service handbook for further instrucons.
CURRENT FAULT
Water Valve Module Disconnected
Occurred:
04/28/2024 12:34 AM
Communication with the water valve module
has been lost.
MORE
92 • High-Eciency Commercial Gas Water Heaters
Troubleshoong
Fault and Alert Messages
FAULT CODE Possible Causes - Check/Repair Displayed Fault/Alert Message
210
Data Error Code:
(210, 35)
Auto Test Complete
Cycle Main Power to water heater. If problem connues,
contact technical support for further instrucons.
CURRENT FAULT
Auto Test Complete/Passed
Occurred:
04/28/2025 12:34 AM
No action required.
MORE
211
Data Error Code:
(211, 133)
No Blower Speed Feedback
The control system has not detected the correct feedback
from the blower when a command was sent to the blower
to operate.
1. Ensure both wire connecons to the blower and to the
control system is secure and free of contaminates.
2. Ensure the wire harnesses are free from damages.
3. If problem connue, contact technical support, or refer
to the service handbook for further instrucons.
CURRENT FAULT
No Blower Speed Feedback
Occurred:
04/28/2025 12:34 AM
The control system has detected an issue
with the main temperature probe.
MORE
212
Data Error Code:
(212, xxx) where xxx -
142, 143,
144 or 146
Main Temperature Probe Failure
The control system has detected an issue with the main
temperature probe.
The control system has detected an issue with the main
temperature probe.
1. Ensure the wire connecons for the main temp probe
are clean and secure.
2. Ensure the wire harness for the main temp probe is free
from damages.
3. If the problem connues, contact technical support or
refer to the service handbook for further instrucons.
CURRENT FAULT
Main Temperature Probe Failure
Occurred:
04/28/2025 12:34 AM
The control system has detected an issue
with the main temperature probe.
MORE
213
Data Error Code:
(213, 136) or
(213, 243)
Hardware Failure
The control system has detected a ame sensor error.
1. Ensure that the ame sensor wire harness is free of
damages.
2. Ensure that the ame sensor wire connecon on both
ends is secure and free of contaminates.
3. Remove ame sensor and inspect for contaminates or
damages in ceramic insulator.
4. Clean ame sensor rod with steel wool.
5. If the problem connues, contact technical support, or
refer to the service handbook for further instrucons.
CURRENT FAULT
Hardware Failure
Occurred:
04/28/2025 12:34 AM
The control system has detected a flame
sensor error.
MORE
Troubleshoong
High-Eciency Commercial Gas Water Heaters • 93
Fault and Alert Messages
FAULT CODE Possible Causes - Check/Repair Displayed Fault/Alert Message
214
Data Error Code:
(214, xxx) where xxx
=149, 153, 155 or 157
Software Failure
The CSC has detected a soware issue.
1. Cycle the main power supply to the water heater
by turning o the breaker/disconnect, then wait
approximately 30 seconds and turn main power supply
back on.
2. If problem connues, contact Technical Support or refer
to the service handbook for further instrucons.
CURRENT FAULT
Software Failure
Occurred:
04/28/2025 12:34 AM
The CSC has detected a software issue.
MORE
215
Data Error Code:
(215, 2400x) where
x is the failed
calibration reason
described in the
service handbook.
Calibration Error
The CSC has detected a calibraon error.
1. The CSC has detected a soware issue.
2. Cycle the main power supply to the water heater
by turning o the breaker/disconnect, then wait
approximately 30 seconds and turn main power supply
back on.
3. If problem connues, contact Technical Support or refer
to the service handbook for further instrucons.
CURRENT FAULT
Calibration Error
Occurred:
04/28/2025 12:34 AM
The CSC has detected a calibration error.
MORE
216
Data Error Code:
(216, 137)
Gas Valve Circuit Fault
The control system has detected a fault with the Gas Valve
Circuit.
1. Ensure wire connecons on both ends are secure and
free of contaminates.
2. Ensure wire harness is not damaged.
3. If problem connues, contact technical support, or refer
to the service handbook for further instrucons.
CURRENT FAULT
Gas Valve Circuit Fault
Occurred:
04/28/2025 12:34 AM
The control system has detected a fault with
the Gas Valve Circuit.
MORE
217
Data Error Code:
(217, 242)
MDT Fault
The control system has detected a fault with the Motor Driven
Throle (MDT).
1. Ensure wire connecons on both ends are secure and
free of contaminates.
2. Ensure wire harness is not damaged.
3. If problem connues, contact technical support, or refer
to the service handbook for further instrucons.
CURRENT FAULT
MDT Fault
Occurred:
04/28/2025 12:34 AM
The control system has detected a fault with
the Motor Driven Throttle (MDT).
MORE
218
Data Error Code:
(209, 2014)
BMS Module Disconnected
Communicaon with the BMS module has been lost.
The control system has detected that the BMS is disconnected.
1. Ensure BMS module is powered.
2. Ensure wire connecons are secure and free of
contaminates.
3. Ensure wire harness is free of damages.
4. If problem connues, contact technical support or refer
to the service handbook for further instrucons.
CURRENT FAULT
BMS Module Disconnected
Occurred:
04/28/2025 12:34 AM
Communication with the BMS module has
been lost.
MORE
94 • High-Eciency Commercial Gas Water Heaters
Troubleshoong
Fault and Alert Messages
FAULT CODE Possible Causes - Check/Repair Displayed Fault/Alert Message
219
Anode Shorted
The central control board (TRC) is detecng low-resistance
or a short to earth ground or the tank.
Possible Causes:
1. Water at anode area.
2. Contaminaon (solder, Locte, WD40 etc.) between the
anode top and the surrounding metal.
3. Sediment build up with a possible bridge to tank.
4. A loose anode wire touching the tank.
5. A bent anode shorng to the tank or an element.
CURRENT FAULT
Anode Shorted
Occurred:
04/28/2025 12:34 AM
The external powered anode circuit is
shorted to earth ground or the tank.
MORE
220
Powered Anode Module Failure
Cycle the main power to the unit o and then on.
The commercial power anode module (CPAM) needs to be
replaced.
CURRENT FAULT
Power Anode Module failure
Occurred:
09/08/2020 12:34 AM
The external powered anode circuit has a
failure.
MORE
221
Data Error Code:
13
Reset Lockout
The control system has detected a Reset Lockout
1. Cycle the main power to the water heater.
2. If problem connues, contact technical support, or
refer to the service handbook for further instrucons.
CURRENT FAULT
Reset Lockout
Occurred:
04/28/2025 12:34 AM
The Combustion Safety control (CSC)
detected more than 5 resets within 15
minutes.
MORE
222
Data Error Code:
(222, 2001)
FMM Missing
The control system has detected that the Flex Memory
Module (FMM) is either missing or disconnected.
1. Ensure the wire connecons are secure and free of
contaminates.
2. Ensure wire connecon at terminal J2 on the TRC is
secure.
3. Ensure all wire harnesses are free from damages.
4. Cycle the main power to the water heater.
5. If problem connues, contact technical support for
further instrucons.
CURRENT FAULT
FMM Missing
Occurred:
04/28/2025 12:34
The control system has detected that the
Flex Memory Module (FMM) is either
missing or disconnected.
MORE
Troubleshoong
High-Eciency Commercial Gas Water Heaters • 95
Fault and Alert Messages
FAULT CODE Possible Causes - Check/Repair Displayed Fault/Alert Message
223
Data Error Code:
(223, 2006)
Missing Display
The display was found to be missing.
The control system has detected that the User Interface
Module (UIM) is either missing or disconnected.
1. Ensure the wire connecons are secure and free of
contaminates.
2. Ensure wire connecon at terminal J2 on the TRC is
secure.
3. Ensure all wire harnesses are free from damages.
4. Cycle the main power to the water heater.
5. If problem connues, contact technical support for
further instrucons.
CURRENT FAULT
Missing Display
Occurred:
04/28/2025 12:34
The control system has detected that the
Flex Memory Module (FMM) is either
missing or disconnected.
MORE
224
Data Error Code:
(224, 2005)
TRC Software or Hardware Is Old
The control system has detected that the Software or
Hardware Version on the TRC is outdated.
The control system has detected that the Software or
Hardware Version on the TRC is outdated.
1. Typically caused by replacing control system
components with an older revision soware.
2. Contact technical support for further instrucons.
CURRENT FAULT
TRC Software or Hardware Is Old
Occurred:
04/28/2025 12:34 AM
The control system has detected that the
Software or Hardware Version on the TRC is
outdated.
MORE
225
(225, 2007)
Display software or hardware is old.
The control system has detected that the Soware Hardware
Version on the UIM is outdated.
1. Typically caused by replacing control system
components with an older revision soware.
2. Contact technical support for further instrucons.
CURRENT FAULT
Display software or hardware is old.
Occurred:
04/28/2025 12:34 AM
The control system has detected that the
Software Hardware Version on the UIM is
outdated
MORE
226
(226, 60xy)
where
x = 0 is on TRC-1000
board anode circuit.
x = 1 is CPAM 1,
x = 2 is CPAM 2 etc.
y = 1, 2, 3, 5, 6 or 8)
Powered Anode Circuit Failure
The control system has detected a failure with the Powered
Anode Circuit.
1. Cycle main power to the water heater.
2. Contact technical support for further instrucons.
CURRENT FAULT
Powered Anode Circuit Failure
Occurred:
04/28/2025 12:34
The control system has detected a failure
with the Powered Anode Circuit.
MORE
96 • High-Eciency Commercial Gas Water Heaters
Troubleshoong
Fault and Alert Messages
FAULT CODE Possible Causes - Check/Repair Displayed Fault/Alert Message
227
(227, 4001)
FMM Incompatible
The control system has detected that the Soware Version
on the Flex Memory Module (FMM) is outdated.
The control system has detected that the Soware Version
on the Flex Memory Module (FMM) is outdated
1. Typically caused by replacing control system components
with an older revision soware
2. Contact technical support for further instrucons
CURRENT FAULT
FMM Incompatible
Occurred:
04/28/2025 12:34 AM
The control system has detected that the
Software Version on the Flex Memory
Module (FMM) is outdated.
MORE
228
(228, 2015)
User Setpoints Error Detected
Data corrupon of user adjustable setpoints led to factory
reset of default values.
Toggle the Enable/Disable switch to disable, wait 30 seconds
and toggle back to Enable to clear fault and readjust
setpoints.
CURRENT FAULT
User Setpoints Error Detected
Occurred:
04/28/2025 12:34 AM
Data corruption of user adjustable setpoints
led to factory reset of default values.
MORE
Troubleshoong
High-Eciency Commercial Gas Water Heaters • 97
CHECKING FOR LEAKS
1
2
3
4
7
10
6
5
8
9
11
Figure 81. Leakage Checkpoints
Failure to follow these instrucons and safety
messages could result in death or serious injury.
Read and understand this instrucon manual and the
safety messages herein before installing, operang or
servicing this water heater.
This manual must remain with the water heater.
⚠
WARNING
Safety Hazard
Never use this water heater unless it is completely lled with water.
To prevent damage to the tank, the tank must be lled with water.
Water must ow from the hot water faucet before turning “ON” gas
to the water heater.
1. *The anode rod ngs may be leaking.
2. *Condensaon may be seen on pipes in humid weather or pipe
connecons may be leaking.
3. Condensate from the exhaust connecon.
4. Leakage from recirculaon plug or pipe connecon.
5. *The drain valve may be leaking at the tank ng.
6. Water from a drain valve may be due to the valve being slightly
opened.
7. Leakage from the plug under the clean-out cover.
8. Small amounts of water from temperature-pressure relief valve may
be due to thermal expansion or high water pressure in your area.
9. Leakage from the temperature probe connecon (Not shown in
gure).
10. The temperature probe fitting may be leaking. See
Checking
Threaded Fittings.
11. The temperature-pressure relief valve may be leaking at the tank
ng. See
Checking Threaded Fittings.
Leakage from other water heaters, water lines, or ground seepage
should also be checked.
CHECKING THREADED FITTINGS
To check where threaded poron enters tank for leaks, do the following:
1. Insert coon swab between jacket opening and ng.
2. If coon is wet, follow drain the tank
and then remove ng. See
Draining the Water Heater Storage Tank
(page 76)
.
3. Put pipe dope or thread-sealer tape on the threads and replace.
4. Then follow the instrucons in
Filling The Water Heater
(page 53).
98 • High-Eciency Commercial Gas Water Heaters
DIAGRAMS
WIRING DIAGRAMS
Circulation Pump Wiring Diagrams
FIELD SUPPLIED TEMPERATURE CONTROL
INSTALLED IN THE STORAGE TANK
OR CIRCULATING LOOP RETURN LINE
CIRC
PUMP
MOTOR
L1 HOT
L2 NEUTRAL
120 VAC
POWER
NOTE: USE SEPARATE 120 VAC POWER
SUPPLY FOR PUMP CIRCUIT. DO NOT
SHARE POWER WITH APPLIANCE AS THIS
MAY CAUSE ELECTRICAL LINE NOISE AND
LEAD TO ERRATIC CONTROL SYSTEM
OPERATION.
Figure 82. Recirculating Loop with Storage Tank or Building Recirculation
FIELD SUPPLIED TEMPERATURE
CONTROL INSTALLED IN THE
CIRCULATING LOOP RETURN LINE
DISHWASHER
TOGGLE
SWITCH
CIRC
PUMP
MOTOR
L1 HOT
L2 NEUTRAL
120 VAC
POWER
NOTE: USE SEPARATE 120 VAC POWER
SUPPLY FOR PUMP CIRCUIT. DO NOT
SHARE POWER WITH APPLIANCE AS THIS
MAY CAUSE ELECTRICAL LINE NOISE AND
LEAD TO ERRATIC CONTROL SYSTEM
OPERATION.
Figure 83. Recirculating Loop with Dish Washer and Toggle Switch
Diagrams
High-Eciency Commercial Gas Water Heaters • 99
Control Circuit Diagrams
J7
J13
12
43
1 2
3
4
76
5
8 9 10
1
2 3
4
109
65
11
12 13 14
123
45
6
123
67
8
45
9
10
87
15 16
X5
X7
X1
X3
X10
FF2
FF1
Blower Power
Hall Sensor
PWM
GND
24Vdc
L1
N
PE/GND
Gas Valves
Motor Driven
N
L1
Connected to
heater jacket
PE/GND
NTC1
NTC2
Main Temperature Probe
Flame Sensor Rod
Spark XFMR
NTC3
NTC Lower
Connected to
tank
1(L1)
2(N)
3(PE)
1
23
4
10
6 5
11121314
8
7
1516
J6
9
18 17
123
4
6 5
8
7
J8
1
23
45
1
23
45
1
23
4 15
23
J2
J3
J9
J4
9876
1
J5
J10
Enable/Disable Switch
(LDM)
Display 2.0
FMM
Key
Powered Anode 1 & 2
Field Wiring
L1 PE/GNDN
+5V
D+
D-
DGND
+5V
D+
D-
DGND
+5V
D+
D-
DGND
D+
D-
DGND
Outlet Air
Inlet Air
Spark Rod
Connected to
tank PE/GND
Pressure SW
Pressure SW
TEMPERATURE
REGULATION CONTROL
(TRC)
COMBUSTION & SAFETY
CONTROL
(CSC)
NO FACTORY
CONNECTIONS
NO FACTORY
CONNECTIONS
AC Power
120 Vac/60Hz
Junction Box
PE/GND
P1
P2
P3
P4
P5
P6
P7
P8
OPEN
OPEN
OPEN
OPEN
CPAM N
CPAM L1
L1
N
L1
N
PE/GND
(OAPS)
(IAPS)
PE/GND
PE/GND
L1
N
Leak Detection Module
Connected to tank
PE/GND
Throttle (MDT)
Blower Command
NO FACTORY
CONNECTIONS
123456
NO FACTORY
CONNECTIONS
NO FACTORY
CONNECTIONS
123
S4962VX1018
Field Wiring
WHITE
BLACK
GREEN
GREEN
BLACK
WHITE
WHITE
WHITE
GREEN
GREEN
GREEN
BLACK
BLACK
BLACK
BLACK
BLACK
BLACK
GREEN
WHITE
GREEN
GREEN
WHITE
GREEN
BLUEBLUE
ORANGE
ORANGE
BROWN
BROWN
BLUE
BLUE
WHITE
WHITE
BLACK
BLACK
GREY
GREY
VIOLET
VIOLET
BLACK
YELLOW
123
4
6 5
8
7
123
4
6 5
8
7
ORANGE
ORANGE
INNER EXT
BLACK
GREEN
BLUE
BLACK
WHITE
WHITE
GREEN
RED
BLUE
YELLOW
GREEN
RED
YELLOW
BLUE
BLACK
GREY
VIOLET
RED
YELLOW
GREEN
RED
BLACK
BLUE
WHITE
12
4 3
12
4 3
2A
2
1A
1
WHITE
BLACK
GREEN
RED
1234
1234
RED
YELLOW
BLUE
BLACK
NO FACTORY
CONNECTIONS
P1, P2, P3, P4, P5, and P6 ARE NOT USED
GREEN
5
4
3
2
8765
2
1
3
4
EXTERNAL ENABLE
DISABLE SWITCH
Alarm
Louvre
Figure 84. 60 Gallon Models Temperature Regulation and Combustion and Safety Control Wiring Diagram
100 • High-Eciency Commercial Gas Water Heaters
Diagrams
J7
J13
12
43
1 2
3
4
76
5
8 9 10
1
2 3
4
109
65
11
12 13 14
123
45
6
123
67
8
45
9
10
87
15 16
X5
X7
X1
X3
X10
FF2
FF1
Blower Power
Hall Sensor
PWM
GND
24Vdc
L1
N
PE/GND
Gas Valves
Motor Driven
N
L1
Connected to
heater jacket
PE/GND
NTC1
NTC2
Main Temperature Probe
Flame Sensor Rod
Spark XFMR
NTC3
NTC Lower
Connected to
tank
1(L1)
2(N)
3(PE)
1
23
4
10
6 5
11121314
8
7
1516
J6
9
18 17
123
4
6 5
8
7
J8
1
23
45
1
23
45
1
23
4 15
23
J2
J3
J9
J4
9876
1
J5
J10
Enable/Disable Switch
(LDM)
Display 2.0
FMM
Key
Powered Anode 1 & 2
Field Wiring
L1 PE/GNDN
+5V
D+
D-
DGND
+5V
D+
D-
DGND
+5V
D+
D-
DGND
D+
D-
DGND
Outlet Air
Inlet Air
Spark Rod
Connected to
tank PE/GND
Pressure SW
Pressure SW
TEMPERATURE
REGULATION CONTROL
(TRC)
COMBUSTION & SAFETY
CONTROL
(CSC)
NO FACTORY
CONNECTIONS
NO FACTORY
CONNECTIONS
AC Power
120 Vac/60Hz
Junction Box
PE/GND
P1
P2
P3
P4
P5
P6
P7
P8
OPEN
OPEN
OPEN
OPEN
CPAM N
CPAM L1
L1
N
L1
N
PE/GND
(OAPS)
(IAPS)
PE/GND
PE/GND
L1
N
Leak Detection Module
Connected to tank
PE/GND
Throttle (MDT)
Blower Command
NO FACTORY
CONNECTIONS
123456
NO FACTORY
CONNECTIONS
NO FACTORY
CONNECTIONS
123
S4962VX1018
Field Wiring
WHITE
BLACK
GREEN
GREEN
BLACK
WHITE
WHITE
WHITE
GREEN
GREEN
GREEN
BLACK
BLACK
BLACK
BLACK
BLACK
BLACK
GREEN
WHITE
GREEN
GREEN
WHITE
GREEN
BLUEBLUE
ORANGE
ORANGE
BROWN
BROWN
BLUE
BLUE
WHITE
WHITE
BLACK
BLACK
GREY
GREY
VIOLET
VIOLET
BLACK
YELLOW
123
4
6 5
8
7
123
4
6 5
8
7
ORANGE
ORANGE
INNER EXT
BLACK
GREEN
BLUE
BLACK
WHITE
WHITE
GREEN
RED
BLUE
YELLOW
GREEN
RED
YELLOW
BLUE
BLACK
GREY
VIOLET
RED
YELLOW
GREEN
RED
BLACK
BLUE
WHITE
12
4 3
12
4 3
2A
2
1A
1
WHITE
BLACK
GREEN
RED
1234
1234
RED
YELLOW
BLUE
BLACK
NO FACTORY
CONNECTIONS
P1, P2, P3, P4, P5, and P6 ARE NOT USED
GREEN
5
4
3
2
8765
2
1
3
4
EXTERNAL ENABLE
DISABLE SWITCH
Alarm
Louvre
Figure 85. 100 Gallon Models - Temperature Regulation and Combustion and Safety Control Wiring Diagram
Diagrams
High-Eciency Commercial Gas Water Heaters • 101
J13
J7
43
1 2
3
4
76
5
8 9 10
1
2 3
4
109
65
11
12 13 14
123
45
6
123
67
8
45
9
10
87
15 16
X5
X7
X1
X3
X10
FF2
FF1
Blower Power
Hall Sensor
PWM
GND
24Vdc
L1
N
PE/GND
Gas Valves
Motor Driven
N
L1
Connected to
heater jacket
PE/GND
NTC1
NTC2
Main Temperature Probe
Flame Sensor Rod
Spark XFMR
NTC3
NTC Lower
Connected to
tank
1(L1)
2(N)
3(PE)
1
23
4
10
6 5
11121314
8
7
1516
J6
9
18 17
123
4
6 5
8
7
J8
1
23
45
1
23
45
1
23
45 1
23
1
2
J2
J3
J9
J4
98764 52 31
J5
J10
Enable/Disable Switch
(LDM)
Display 2.0
FMM
KEY
Powered Anode 1 & 2
Alarm
Field Wiring
L1 PE/GNDN
+5V
D+
D-
DGND
+5V
D+
D-
DGND
+5V
D+
D-
DGND
D+
D-
DGND
Outlet Air
Inlet Air
Spark Rod
Connected to
tank PE/GND
Pressure SW
Pressure SW
CPAM
TEMPERATURE
REGULATION CONTROL
(TRC)
COMBUSTION & SAFETY
CONTROL
(CSC)
CPAM
Power Supply
12VDC
NO FACTORY
CONNECTIONS
NO FACTORY
CONNECTIONS
AC Power
120 Vac/60Hz
Junction Box
PE/GND
P1, P2, P3, and P4 ARE NOT USED
P1
P2
P3
P4
P5
P6
P7
P8
OPEN
OPEN
OPEN
OPEN
CPAM N
CPAM L1
L1
N
L1
N
PE/GND
(OAPS)
(IAPS)
PE/GND
PE/GND
L1
N
Leak Detection Module
Powered Anode 3
Connected to tank
PE/GND
Connected to tank
PE/GND
Throttle (MDT)
Blower Command
NO FACTORY
CONNECTIONS
123456
NO FACTORY
CONNECTIONS
NO FACTORY
CONNECTIONS
123
S4962VX1018
Field Wiring
WHITE
BLACK
GREEN
GREEN
GREEN
BLACK
BLACK
WHITE
WHITE
WHITE
WHITE
GREEN
GREEN
GREEN
BLACK
BLACK
BLACK
BLACK
BLACK
BLACK
BLACK
GREEN
WHITE
GREEN
GREEN
WHITE
GREEN
BLUEBLUE
ORANGE
ORANGE
BROWN
BROWN
BLUE
BLUE
W
HITE
WHITE
BLACK
BLACK
GREY
GREY
VIOLET
VIOLET
BLACK
YELLOW
123
4
6 5
8
7
123
4
6 5
8
7
ORANGE
ORANGE
INNER EXT
BLACK
GREEN
BLUE
BLACK
WHITE
WHITE
GREEN
RED
GREEN
BLACK
BLUE
YELLOW
GREEN
WHT/OR
WHT/BR
BLUE
WHT/BL
RED
YELLOW
BLUE
BLACK
BLACK
GREY
VIOLET
RED
YELLOW
GREEN
RED
BLACK
BLUE
WHITE
12
4 3
12
4 3
2A
2
1A
1
WHITE
BLACK
GREEN
RED
1234
1234
RED
YELLOW
BLUE
BLACK
Louvre
8765
2
1
3
4
EXTERNAL ENABLE
DISABLE SWITCH
Figure 86. 119 Gallon Models Temperature Regulation and Combustion and Safety Control Circuit Diagram
102 • High-Eciency Commercial Gas Water Heaters
Diagrams
WATER PIPING DIAGRAMS
One Water Heater, Single Temperature with Building Recirculation
Before installaon of water piping review the following:
1. See
Mixing Valves
(page 21).
2. See
Dish-washing Machines
(page 21).
3. See
Temperature-Pressure Relief Valve
(page 22).
4. See
Closed Water Systems
(page 21)
and
Thermal Expansion
(page
21).
5. See
Water Line Connections
(page 51).
6. If a pump is being installed between a water heater and storage
tank or on a building recirculaon loop wire according to
Figure 82
(page 98).
7. If a pump is being installed in a recirculaon loop between the
water heater and a commercial dishwasher wire according to
Figure
83
(page 98).
WARNING: THIS DRAWING SHOWS A
SUGGESTED PIPING CONFIGURATION AND
OTHER DEVICES. CHECK WITH LOCAL CODES
AND ORDINANCES FOR ADDITIONAL
REQUIREMENTS.
ANY MATERIAL, COMPONENT, OR VENDOR
CHANGE MUST HAVE PRIOR APPROVAL BY
THE APPLICABLE PRODUCT ENGINEERING
DEPARTMENT.
LEGEND
Temperature & Pressure Relief Valve
Pressure Relief Valve
Circulang Pump
Tank Temperature Control
Drain Valve
Full-Port Ball Valve
Check Valve
Temperature Gage
Water Flow Switch
Mixing Valve
M
Shut-Off Valve
Expansion Tank
Cold Water
Supply
Finished Floor
Hot Water to Fixtures
Pipe T&P Valve
to Open Drain
Floor Drain
Hot Water
Return
M
M
M
NOTES:
1. Preferred piping diagram.
2. The temperature and pressure relief valve setting shall not exceed pressure rating of any component in the system.
3. Service valves are shown for servicing unit. However, local codes shall govern their usage.
4. Ensure that any installed recirculation system does not bypass or interfere in any way with shut-off valves.
Diagrams
High-Eciency Commercial Gas Water Heaters • 103
One Water Heater, Two Temperatures with High-Temperature Loop Recirculation - With Building Recirculation
Before installaon of water piping review the following:
1. See
Mixing Valves
(page 21).
2. See
Dish-washing Machines
(page 21).
3. See
Temperature-Pressure Relief Valve
(page 22).
4. See
Closed Water Systems
(page 21)
and
Thermal Expansion
(page
21).
5. See
Water Line Connections
(page 51).
6. If a pump is being installed between a water heater and storage
tank or on a building recirculaon loop wire according to
Figure 82
(page 98).
7. If a pump is being installed in a recirculaon loop between the
water heater and a commercial dishwasher wire according to
Figure
83
(page 98).
WARNING: THIS DRAWING SHOWS A
SUGGESTED PIPING CONFIGURATION AND
OTHER DEVICES. CHECK WITH LOCAL CODES
AND ORDINANCES FOR ADDITIONAL
REQUIREMENTS.
ANY MATERIAL, COMPONENT, OR VENDOR
CHANGE MUST HAVE PRIOR APPROVAL BY
THE APPLICABLE PRODUCT ENGINEERING
DEPARTMENT.
LEGEND
Temperature & Pressure Relief Valve
Pressure Relief Valve
Circulang Pump
Tank Temperature Control
Drain Valve
Full-Port Ball Valve
Check Valve
Temperature Gage
Water Flow Switch
Mixing Valve
M
Shut-Off Valve
M
M
M
Pipe T&P to
Open Drain
Hot Water
Return
Tempered
Water Outlet
Outlet
Tempered
Water Return
Cold Water
Supply
Expansion
Tank
Cold
Hot
Finished Floor
Floor Drain
12” to 15”
Mixing Valve
NOTES:
1. Preferred piping diagram.
2. The temperature and pressure relief valve setting shall not exceed pressure rating of any component in the system.
3. Service valves are shown for servicing unit. However, local codes shall govern their usage.
4. Ensure that any installed recirculation system does not bypass or interfere in any way with shut-off valves.
104 • High-Eciency Commercial Gas Water Heaters
Diagrams
One Water Heater, Single Temperature with Vertical Storage Tank Forced Recirculation with Building Recirculation
Before installaon of water piping review the following:
1. See
Mixing Valves
(page 21).
2. See
Dish-washing Machines
(page 21).
3. See
Temperature-Pressure Relief Valve
(page 22).
4. See
Closed Water Systems
(page 21)
and
Thermal Expansion
(page
21).
5. See
Water Line Connections
(page 51).
6. If a pump is being installed between a water heater and storage
tank or on a building recirculaon loop wire according to
Figure 82
(page 98).
7. If a pump is being installed in a recirculaon loop between the
water heater and a commercial dishwasher wire according to
Figure
83
(page 98).
WARNING: THIS DRAWING SHOWS A
SUGGESTED PIPING CONFIGURATION AND
OTHER DEVICES. CHECK WITH LOCAL CODES
AND ORDINANCES FOR ADDITIONAL
REQUIREMENTS.
ANY MATERIAL, COMPONENT, OR VENDOR
CHANGE MUST HAVE PRIOR APPROVAL BY
THE APPLICABLE PRODUCT ENGINEERING
DEPARTMENT.
LEGEND
Temperature & Pressure Relief Valve
Pressure Relief Valve
Circulang Pump
Tank Temperature Control
Drain Valve
Full-Port Ball Valve
Check Valve
Temperature Gage
Water Flow Switch
Mixing Valve
M
Shut-Off Valve
STORAGE TANK
Pipe T&P to
Open Drain
Hot
Water
Return
Hot Water to Fixtures
Alternate Cold
Water Connecon
Cold Water
Supply
Expansion
Tank
Finished Floor
Floor Drain
M
M
NOTES:
1. Preferred piping diagram.
2. The temperature and pressure relief valve setting shall not exceed pressure rating of any component in the system.
3. Service valves are shown for servicing unit. However, local codes shall govern their usage.
4. The tank temperature control should be wired to and control the pump between the water heater(s) and the storage tank(s).
5. The water heater’s operating thermostat should be set 5 degrees F higher than the tank temperature control.
6. Ensure that any installed recirculation system does not bypass or interfere in any way with shut-off valves.
Diagrams
High-Eciency Commercial Gas Water Heaters • 105
One Water Heater, Single Temperature with Horizontal Storage Tank, Forced Recirculation with Building Recirculation
Before installaon of water piping review the following:
1. See
Mixing Valves
(page 21).
2. See
Dish-washing Machines
(page 21).
3. See
Temperature-Pressure Relief Valve
(page 22).
4. See
Closed Water Systems
(page 21)
and
Thermal Expansion
(page
21).
5. See
Water Line Connections
(page 51).
6. If a pump is being installed between a water heater and storage
tank or on a building recirculaon loop wire according to
Figure 82
(page 98).
7. If a pump is being installed in a recirculaon loop between the
water heater and a commercial dishwasher wire according to
Figure
83
(page 98).
WARNING: THIS DRAWING SHOWS A
SUGGESTED PIPING CONFIGURATION AND
OTHER DEVICES. CHECK WITH LOCAL CODES
AND ORDINANCES FOR ADDITIONAL
REQUIREMENTS.
ANY MATERIAL, COMPONENT, OR VENDOR
CHANGE MUST HAVE PRIOR APPROVAL BY
THE APPLICABLE PRODUCT ENGINEERING
DEPARTMENT.
LEGEND
Temperature & Pressure Relief Valve
Pressure Relief Valve
Circulang Pump
Tank Temperature Control
Drain Valve
Full-Port Ball Valve
Check Valve
Temperature Gage
Water Flow Switch
Mixing Valve
M
Shut-Off Valve
STORAGE TANK
Pipe T&P to
Open Drain
Hot
Water
Return
Hot Water to Fixtures
Alternate Cold
Water Connecon
Cold Water
Supply
Expansion
Tank
Finished Floor
Floor Drain
Circulang Pump
M
M
NOTES:
1. Preferred piping diagram.
2. The temperature and pressure relief valve setting shall not exceed pressure rating of any component in the system.
3. Service valves are shown for servicing unit. However, local codes shall govern their usage.
4. The tank temperature control should be wired to and control the pump between the water heater(s) and the storage tank(s).
5. The water heater’s operating thermostat should be set 5 degrees F higher than the tank temperature control.
6. Ensure that any installed recirculation system does not bypass or interfere in any way with shut-off valves.
106 • High-Eciency Commercial Gas Water Heaters
Diagrams
Two Water Heaters, Single Temperature with Building Recirculation
Before installaon of water piping review the following:
1. See
Mixing Valves
(page 21).
2. See
Dish-washing Machines
(page 21).
3. See
Temperature-Pressure Relief Valve
(page 22).
4. See
Closed Water Systems
(page 21)
and
Thermal Expansion
(page
21).
5. See
Water Line Connections
(page 51).
6. If a pump is being installed between a water heater and storage
tank or on a building recirculaon loop wire according to
Figure 82
(page 98).
7. If a pump is being installed in a recirculaon loop between the
water heater and a commercial dishwasher wire according to
Figure
83
(page 98).
WARNING: THIS DRAWING SHOWS A
SUGGESTED PIPING CONFIGURATION AND
OTHER DEVICES. CHECK WITH LOCAL CODES
AND ORDINANCES FOR ADDITIONAL
REQUIREMENTS.
ANY MATERIAL, COMPONENT, OR VENDOR
CHANGE MUST HAVE PRIOR APPROVAL BY
THE APPLICABLE PRODUCT ENGINEERING
DEPARTMENT.
LEGEND
Temperature & Pressure Relief Valve
Pressure Relief Valve
Circulang Pump
Tank Temperature Control
Drain Valve
Full-Port Ball Valve
Check Valve
Temperature Gage
Water Flow Switch
Mixing Valve
M
Shut-Off Valve
M
M
M
M
M
M
Hot
Water
Return
Cold Water
Supply
Expansion
Tank
Circulang Pump
Pipe T&P to
Open Drain
Hot Water to Fixtures
Finished Floor
Floor Drain
NOTES:
1. Preferred piping diagram.
2. The temperature and pressure relief valve setting shall not exceed pressure rating of any component in the system.
3. Service valves are shown for servicing unit. However, local codes shall govern their usage.
4. Ensure that any installed recirculation system does not bypass or interfere in any way with shut-off valves.
Diagrams
High-Eciency Commercial Gas Water Heaters • 107
Three Water Heaters, Single Temperature with Building Recirculation
Before installaon of water piping review the following:
1. See
Mixing Valves
(page 21).
2. See
Dish-washing Machines
(page 21).
3. See
Temperature-Pressure Relief Valve
(page 22).
4. See
Closed Water Systems
(page 21)
and
Thermal Expansion
(page
21).
5. See
Water Line Connections
(page 51).
6. If a pump is being installed between a water heater and storage
tank or on a building recirculaon loop wire according to
Figure 82
(page 98).
7. If a pump is being installed in a recirculaon loop between the
water heater and a commercial dishwasher wire according to
Figure
83
(page 98).
WARNING: THIS DRAWING SHOWS A
SUGGESTED PIPING CONFIGURATION AND
OTHER DEVICES. CHECK WITH LOCAL CODES
AND ORDINANCES FOR ADDITIONAL
REQUIREMENTS.
ANY MATERIAL, COMPONENT, OR VENDOR
CHANGE MUST HAVE PRIOR APPROVAL BY
THE APPLICABLE PRODUCT ENGINEERING
DEPARTMENT.
LEGEND
Temperature & Pressure Relief Valve
Pressure Relief Valve
Circulang Pump
Tank Temperature Control
Drain Valve
Full-Port Ball Valve
Check Valve
Temperature Gage
Water Flow Switch
Mixing Valve
M
Shut-Off Valve
M
M
M
M
M
M
M
M
M
Hot Water
Return
Circulang
Pump
Tank
Temperature
Control
Cold Water
Supply
Expansion
Tank
Floor Drain
Pipe T&P to
Open Drain
Hot Water to Fixtures
Finished Floor
Pipe T&P to
Open Drain
Pipe T&P to
Open Drain
NOTES:
1. Preferred piping diagram.
2. The temperature and pressure relief valve setting shall not exceed pressure rating of any component in the system.
3. Service valves are shown for servicing unit. However, local codes shall govern their usage.
4. Ensure that any installed recirculation system does not bypass or interfere in any way with shut-off valves.
108 • High-Eciency Commercial Gas Water Heaters
Diagrams
Four Water Heaters, Single Temperature with Building Recirculation
Before installaon of water piping review the following:
1. See
Mixing Valves
(page 21).
2. See
Dish-washing Machines
(page 21).
3. See
Temperature-Pressure Relief Valve
(page 22).
4. See
Closed Water Systems
(page 21)
and
Thermal Expansion
(page
21).
5. See
Water Line Connections
(page 51).
6. If a pump is being installed between a water heater and storage
tank or on a building recirculaon loop wire according to
Figure 82
(page 98).
7. If a pump is being installed in a recirculaon loop between the
water heater and a commercial dishwasher wire according to
Figure
83
(page 98).
WARNING: THIS DRAWING SHOWS A
SUGGESTED PIPING CONFIGURATION AND
OTHER DEVICES. CHECK WITH LOCAL CODES
AND ORDINANCES FOR ADDITIONAL
REQUIREMENTS.
ANY MATERIAL, COMPONENT, OR VENDOR
CHANGE MUST HAVE PRIOR APPROVAL BY
THE APPLICABLE PRODUCT ENGINEERING
DEPARTMENT.
LEGEND
Temperature & Pressure Relief Valve
Pressure Relief Valve
Circulang Pump
Tank Temperature Control
Drain Valve
Full-Port Ball Valve
Check Valve
Temperature Gage
Water Flow Switch
Mixing Valve
M
Shut-Off Valve
M
M
M
M
M
M
M
M
M
M
M
M
Hot
Water
Return
Circulang
Pump
Tank
Temperature
Control
Hot Water to Fixtures
Pipe T&P to
Open Drain
Cold Water
Supply
Expansion
Tank
Finished Floor
Floor Drain
Pipe T&P to
Open Drain
Pipe T&P to
Open Drain
Pipe T&P to
Open Drain
NOTES:
1. Preferred piping diagram.
2. The temperature and pressure relief valve setting shall not exceed pressure rating of any component in the system.
3. Service valves are shown for servicing unit. However, local codes shall govern their usage.
4. Ensure that any installed recirculation system does not bypass or interfere in any way with shut-off valves.
Diagrams
High-Eciency Commercial Gas Water Heaters • 109
NOTES
110 • High-Eciency Commercial Gas Water Heaters
Diagrams
NOTES
Diagrams
High-Eciency Commercial Gas Water Heaters • 111
NOTES
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