Gas Tankless Water Heater
TM
Suitable for combination potable water heating
and space heating. Please refer to local codes for
space-heating compliance.
If you have any questions,
please call or write to
USA: 500 Tennessee Waltz Parkway
Ashland City, TN 37015
Toll Free: 1-877-737-2840
CANADA: 599 Hill Street West
Fergus, ON N1M 2X1
1-888-479-8324
On-Demand Water Heater
Installation Manual and Owner’s Guide
ANSI Z21.10.3 • CSA 4.3
FEATURING
• INTEGRATED RECIRCULATION PUMP
• ENDLESS HOT WATER
• ON-DEMAND USAGE
• COMPACT, SPACE SAVING
• ENERGY CONSERVATION
• COMPUTERIZED SAFETY
• NO PILOT LIGHT
• Complies with SCAQMD Rule
1146.2 for natural gas NOx
emissions of 14 ng/J or 20 ppm.
• EASY-LINK SYSTEM
Keep this manual near the water heater for future reference whenever maintenance, adjustment or service is required.
- 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 electric 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.
WARNING
If the information in these
instructions is not followed
exactly, a fire or explosion may
result causing property damage,
personal injury or death.
Models
• 540P Indoor
• 540P Outdoor
R
DR
2 Page
Contents
CONTENTS
Installation Manual
SPECIFICATIONS .............................................4
INTRODUCTION ..........................................5
SAFETY GUIDELINES.....................................6
SAFETY DEFINITION ....................................6
GENERAL ......................................................6
INCORPORATED RECIRCULATION PUMP ....... 7
INSTALLATION ................................................7
GENERAL ......................................................7
CLEARANCES ...............................................9
INCLUDED ACCESSORIES ............................9
OPTIONAL ITEMS ........................................ 9
WARNING FOR INSTALLATIONS ...............11
HIGH-ALTITUDE INSTALLATIONS .............12
VENTING INSTRUCTIONS .........................13
General .....................................................13
Combustion air supply ..............................14
Exhaust vent (ABS,PVC,CPVC, or
polypropylene vent) .................................18
DIP switch settings for vent length
(ABS,PVC,CPVC, or polypropylene vent) ...19
Exhaust vent (Stainless steel vent) ...........23
DIP switch settings for vent length
(Stainless steel vent) .................................23
Common venting system ..........................26
Vent termination clearances ....................28
Clearances for sidewall terminations .......29
Clearances for rooftop terminations ........30
GAS SUPPLY AND GAS PIPE SIZING .........31
General .....................................................31
Gas connections .......................................31
Natural Gas supply piping .........................32
Propane (LP) supply piping ....................... 32
WATER CONNECTIONS .............................33
Installation w/ dedicated return line ........33
Installation w/o dedicated return line ......34
Pressure relief valve .................................34
CONDENSATE DRAIN ................................35
Condensate drain connections .................35
ELECTRICAL CONNECTIONS .....................37
TEMPERATURE REMOTE CONTROLLER .....38
Included accessories .................................38
Installation ................................................38
EASY-LINK SYSTEM .........................................40
Easy link connection procedures ..............40
APPLICATIONS ..............................................42
Combination potable water heating
and space heating ......................................42
Recirculation ...............................................42
Dual-purpose hot water heating ................... 43
INITIAL OPERATION .....................................44
Initial test run ...........................................44
Owner's Guide
OPERATING SAFETY .....................................48
NORMAL OPERATION ..................................50
BUILT-IN CONTROLLER
AND REMOTE CONTROLLER ..................50
GENERAL ....................................................50
OUTLET WATER TEMPERATURE
SETTING ..................................................... 51
TEMPERATURE TABLE OF CONTROLLER .51
SETTING THE TIME ...................................52
PUMP OPERATION TIMERS ......................52
Setting pump timers .................................53
Selecting a pump timer ............................55
Display example ........................................56
Manual pump activation ..........................57
Manual pump operation ..........................57
ADDITIONAL FEATURES ...................... ......59
Information mode ....................................59
Unit conversion mode ..............................59
TEMPERATURE SETTINGS ON THE PCB ........60
FLOW .......................................................... 60
FREEZE PROTECTION SYSTEM ................. 61
MAINTENANCE AND SERVICE ................. 62
Measuring inlet gas pressure ...................62
UNIT DRAINING AND FILTER CLEANING .......63
TROUBLESHOOTING .....................................64
GENERAL ....................................................64
ERROR CODES ...........................................66
COMPONENTS DIAGRAM ............................70
PARTS LIST .................................................... 74
OUTPUT TEMPERATURE CHART ..................76
3 Page
Installaon Manual
Installation Manual
CONGRATULATIONS
Congratulations and thank you for choosing our tankless water heater.
Before use, we recommend that you read through this installation
manual carefully. Keep this manual for future reference.
If you need an additional manual, contact the manufacturer or your
local distributor. You may also download a manual from our website.
When you call, please tell us the product name and the serial number
of your unit written on the rating plate of the water heater.
4 Page
Specicaons
Installaon Manual
SPECIFICATIONS
*40 psi or above is recommended for maximum flow.
**Water heater Category — water heaters of other than direct vent type, for outdoor installation, are divided into four
categories based on static pressure produced in the vent and flue loss.
Category I - a water heater that operates with a non-positive vent static pressure and with a vent gas temperature
that avoids excessive condensate production in the vent.
Category II - a water heater that operates with a non-positive vent static pressure and with a vent gas temperature
that may cause excessive condensate production in the vent.
Category III - a water heater that operates with a positive vent static pressure and with a vent gas temperature that
avoids excessive condensate production in the vent.
Category IV - a water heater that operates with a positive vent static pressure and with a vent gas temperature that
may cause excessive condensate production in the vent.
***These are equivalent lengths that include head loss for elbows, tees, unions, etc.
NOTE:
• Check the rating plate to ensure that this product matches your specifications.
• The manufacturer reserves the right to discontinue, or change at any time, specifications or designs
without notice and without incurring obligation.
Model
540P Indoor 540P Outdoor
Natural Gas Input (Operating Range) BTU/h
Min: 15,000
Max.: 199,000
Propane Input (Operating Range) BTU/h
Min: 13,000
Max.: 199,000
Gas Connection 3/4" NPT
Water Connections 3/4" NPT
Water Pressure* psi (MPa) 15 - 150 (0.1 - 1)
Natural gas
Inlet Pressure
" W.C. (kPa) Min 4.0 (1.00) Max. 10.5 (2.61)
Propane
Inlet Pressure
" W.C. (kPa) Min 8.0 (1.99) Max. 14.0 (3.48)
Weight lbs. (kg) 61.0 (27.7)
Dimensions
inch
H 22.4 x W 17.7 x D 10.7
H 570 x W 450 x D 272
mm
Ignition Electric Ignition
Electric
Supply VAC / Hz 120 / 60
Consumption
Operation
With pump W / A 108.6 / 1.34
Without pump W / A 87.6 / 1.10
Standby W / A 4.6 / 0.10
Freeze-Protection W / A 192.3 / 1.63
Water heater Category**
Category IV
N/A
Maximum Pipe length***
(Hot Water supply line and
Dedicated Return line)
Pipe
Diameter
3/4"
( 19 mm)
500 ft (152.4 m)
1/2"
( 13 mm)
200 ft (61.0 m)
5 Page
INTRODUCTION
• This manual provides information necessary for the installation, operation, and maintenance
of the water heater.
• The model description is listed on the rating plate which is attached to the side panel of the
water heater.
• Please read all installation instructions completely before installing this product.
• If you have any problems or questions regarding this equipment, consult the manufacturer or
its local representative.
• This equipment is an on-demand, tankless water heater designed to efficiently supply endless
hot water when properly sized and installed.
• This heater incorporates a recirculation pump for homes with an installed circulation system.
• These high efficiency models have a built-in secondary heat exchanger that absorbs latent
heat from the exhaust gas.
• The 540P Indoor model is only to be installed indoors. The 540P Outdoor model is only to be
installed outdoors.
• The 540P Indoor model is categorized as Category IV when it isn't installed in the direct vent
installation.
• The principle behind tankless water heaters is simple:
Recirculation pump
Primary HX
Secondary HX
Exhaust thermistor
Thermistor
Bypass valve
Water control valve
Thermistor
Thermistor
Thermistor
Cold water
Gas
Hot water
Return line
Flow sensor
Burners
Gas valves
Fan motor
Computer board
Condensate drain port
*This diagram illustrates tankless water heater design concepts only and does not accurately
represent the water heater’s physical description.
1. A hot water tap is turned on.
2. Water enters the heater.
3. The water flow sensor detects the water flow.
4. The computer initiates the fan motor and sends a signal to the igniter to create an ignition spark.
5. The gas ignites and flames appear within the burner chamber.
6. Water circulates through the heat exchanger and then gets hot.
7. Using thermistors to measure temperatures throughout the water heater, the computer modulates
the gas and water valves to ensure proper output water temperature.
8. When the tap is turned off, the unit shuts down.
Introducon
Installaon Manual
6 Page
SAFETY GUIDELINES
SAFETY DEFINITION
GENERAL
1. Follow all local codes, or in the absence of local codes, follow the current edition of the National Fuel Gas
Code: ANSI Z223.1/NFPA 54 in the USA or B149.1 Natural Gas, Propane Installation Code in Canada.
2. Properly ground the unit in accordance with all local codes or in the absence of local codes, with the
National Electrical Codes: ANSI/NFPA 70 in the USA or CSA standard C22.1 Canadian Electrical Code Part
1 in Canada.
3. Carefully plan where you intend to install the water heater. Please ensure:
• Your water heater will have enough combustible air and proper ventilation.
• Locate your heater where water leakage will not damage surrounding areas. (Please refer to p. 8.)
4. Check the rating plate for the correct GAS TYPE, GAS PRESSURE, WATER PRESSURE and ELECTRIC RATING.
*If this unit does not match your requirements, do not install and consult with the manufacturer.
5. If any problem should occur, turn off all hot water taps and turn off the gas. Then call a trained technician
or the Gas Company or the manufacturer.
Safety Guidelines
Installaon Manual
WARNING
• Water temperatures over 125 °F (52 °C) can cause severe burns instantly or death
from scalding. The water temperature is set at 120 °F (50 °C) from the factory to
minimize any scalding risk. Before bathing or showering, always check the water
temperature.
• Do not store or use gasoline or other flammables, vapors, or liquids in the vicinity
of this appliance.
• Do not reverse the water and/or gas connections as this will damage the gas valves
and can cause severe injury or death. Follow the diagram on p. 33 when installing
your water heater.
• Should overheating occur or the gas supply fails to shut off, turn off the manual gas
control valve to the appliance.
• Do not use this appliance if any part has been in contact with or been immersed in
water. Immediately call a qualified installer or service agency to replace a flooded
water heater. Do not attempt to repair the unit. It must be replaced.
• Do not disconnect the electrical supply if the ambient temperature will drop below
freezing. The Freeze Protection System only works if the unit has electrical power.
The warranty will not be covered if the heat exchanger is damaged due to freezing.
Refer to the section on the Freeze Protection System on p. 61 for more information.
• Failure to observe these warnings could result in severe personal injury or death.
WARNING
Indicates an imminently hazardous situation which, if not avoided, could result
in death or serious injury.
CAUTION
Indicates an imminently hazardous situation which, if not avoided, could result
in minor or moderate injury.
Indicates an imminently hazardous situation which, if not avoided, will result in
death or serious injury.
DANGER
Indicates information considered important but not hazard related.
NOTICE
7 Page
INSTALLATION
GENERAL
1. Follow all local codes, or in the absence of local codes, follow the current edition of the National Fuel Gas
Code: ANSI Z223.1/NFPA 54 in the USA or B149.1 Natural Gas, Propane Installation Code in Canada.
2. All gas water heaters require careful and correct installation to ensure safe and efficient operation. This
manual must be followed exactly. Read the “Safety Guidelines” Section.
3. The manifold gas pressure is preset at the factory. It is computer controlled and should not need
adjustment.
4. Maintain proper space for servicing. Install the unit so that it can be connected or removed easily. Refer
to the "Clearances" Section on p. 9 for proper clearances.
5. The water heater must be installed in a location where the proper amount of combustible air will be
available to it at all times without obstructions, or the indoor heater may be direct vented.
6. The electrical connection requires a means of disconnection, to terminate power to the water heater for
servicing and safety purposes.
7. Do not install the unit where the exhaust vent is pointing into any opening in a building or where the noise
may disturb your neighbors. Make sure the vent termination meets the required distance by local code
from any doorway or opening to prevent exhaust from entering a building. (Refer to pp. 11, 28, and 29.)
8. Carefully plan the installation location of the heater and vent terminations. Contaminants such as aerosols,
lint, and fine powders (including flour) can clog the air intake and reduce the operation of the fan. This, in
turn, can cause improper combustion and reduce the life of the water heater. Regularly ensure that the area
around the water heater, vent termination, and air intake is free of dust, debris, and other contaminants. In
environments with a high level of contaminants (laundry facilities, hair salons, pet salons, chemical plants,
commercial kitchens, etc.), direct venting is required.
9. The 540P Indoor is to be installed indoors only. This water heater is equipped with a thermistor and hi-limit
switch for the exhaust gas, detecting excess temperatures within the flue and enabling the appliance
to safely stop operation if needed. These components are always monitoring exhaust gas conditions in
order to prevent heat damage to ABS, PVC, CPVC, or polypropylene (Plastic) venting. If the exhaust gas
temperature exceeds 140 °F (60 °C), these components will enable the appliance to safely stop operation.
These components are not installed on the outdoor model since the exhaust vent is built-in
• If the water heater is used as a direct-vent appliance, the unit requires 3 inch or 4 inch combustion air
supply pipe. The intake pipe must be sealed airtight. Refer to pp. 13 to 30 for more detail.
• Terminating the venting through a sidewall is recommended for the direct-vent system.
• Running the exhaust vent and the intake pipe parallel is recommended.
• Terminating the exhaust and intake on the same wall/surface is recommended. Terminating in the
same pressure zone allows for pressure balancing, which prevents nuisance shutdowns.
• Only install the water heater in a heated area where below freezing temperatures cannot occur. The
warranty does not cover damage caused by freezing.
• The water heater must be securely mounted to a wall or other suitable structure.
10. The 540P Outdoor model is only to be installed outdoors and only in the area with mild, temperate
climates. The Outdoor model shall be wall-mounted or mounted on a stand. Locate the Outdoor model in
an open, unroofed area and maintain the minimum clearances. (Refer to pp. 9 and 11.)
INCORPORATED RECIRCULATION PUMP
This heater incorporates a recirculation pump for homes with an installed circulation system. The pump
provides several useful features:
• The built-in controller and the remote controller (100276687/TM-RE43) offer two timer settings for pump
operation: PUMP TIMER 1 and PUMP TIMER 2. The pump will operate during the times set for TIMER 1
and/or TIMER 2.
• The pump automatically turns on and off during set times depending on the set temperatures for pump
operation. The set point temperature can be set by the built-in controller or the remote controller
(100276687/TM-RE43).
• Instead of the timers, the pump can operate by pressing the PUMP button on the built-in controller or the
remote controller (100276687/TM-RE43). A DIP switch must be turned on to use this control. (Refer to p. 57.)
The maximum pipe length* for the combined hot water supply line and return line is:
• 1/2” (13 mm) pipe: 200 ft (61.0 m)
• 3/4” (19 mm) pipe: 500 ft (152.4 m)
*These are equivalent length that includes head loss for elbows, tees, unions, etc.
Installaon
Installaon Manual
8 Page
Installaon
Installaon Manual
WARNING
• Installation and service must be performed by a qualified installer (for example, a
licensed plumber or gas fitter). Otherwise, the warranty will be void.
• The installer (licensed professional) is responsible for the correct installation of the
water heater and for compliance with all national, state/provincial, and local codes.
• The manufacturer does not recommend installing the water heater in a pit or
location where gas and water can accumulate.
• Do not have the vent terminal pointing toward any operating window, door, or
opening into a building.
• Do not install next to any source of airborne debris, such as a clothes dryer, that
can cause debris to be trapped inside the combustion chamber, unless the system is
direct-vented.
• Do not install the unit where water, debris, or flammable vapors may get into the flue
terminal or the air intake line.
• The manufacturer does not recommend installing the water heater in an attic due
to safety issues. If you install the water heater in an attic:
• Make sure the unit will have enough combustion air and proper ventilation.
Failure to do so could lead to carbon monoxide poisoning or death.
• Keep the area around the water heater clean. When dust collects on the flame
sensor, the water heater will shut down on an error code.
• Place the unit where it will allow easy access for service and maintenance.
• A drain pan, or other means of protection against water damage, is
recommended to be installed under the water heater in case of leaks. See the
NOTICE below.
• The water heater must be securely mounted to a wall or other suitable structure.
• Failure to observe these warnings could result in severe personal injury, death,
and/or property damage.
NOTICE
• The warranty will not cover damage caused by water quality.
• Only potable water can be used with this water heater. Do not introduce pool
or spa water, or any chemically treated water into the water heater.
• Water hardness levels must not exceed 7 grains per gallon (120 ppm) for single
family domestic applications or more than 4 grains per gallon (70 ppm) for
all other types of applications. Water hardness leads to scale formation and
may affect/damage the water heater. Hard water scaling must be avoided or
controlled by proper water treatment.
• Water pH levels must be between 6.5 and 8.5.
• Well water must be treated.
• The manufacturer recommends direct venting when the water heater is installed
in beauty salons, dry cleaners or any other locations in which such chemicals are
present in the air. Some chemicals used in beauty salons or dry cleaners may affect
the flame sensor. In such cases, the water heater may not work properly.
• Although the water heater is designed to operate with minimal sound, the
manufacturer does not recommend installing the unit on a wall adjacent to a
bedroom, or a room that is intended for quiet study or meditation, etc.
• Locate your water heater close to a drain where water leakage will not do damage
to surrounding areas. As with any water heating appliance, the potential for leakage
at some time in the life of the product does exist. A drain pan, or other means of
protection against water damage, is recommended to be installed under the water
heater in case of leaks. In addition, you may install an active water leak detector
with a shutoff valve which can turn off the water supply in the event of a leak. The
manufacturer is not responsible for damage due to water leaks. If you install a drain
pan under the unit, ensure that it will not restrict the combustion air flow.
9 Page
CLEARANCES
Installaon
Installaon Manual
OPTIONAL ITEMS
#
Model
540P Indoor 540P Outdoor
1.
Temperature remote
controller
✓
2.
Pipe cover
✓ ✓
3.
Neutralizer kit
✓ ✓
4.
Sidewall vent
terminator (Hood)
and Wall thimble
✓
5.
3" PVC concentric
termination
✓
6.
Non-return valve
✓
7
4" PVC Adapter
(for non-return valve)
✓
INCLUDED ACCESSORIES
Check that these items below are included with the water heater.
Installation manual
and owner’s guide
Temperature remote controller kit*
Outdoor model only
Bird screen
Indoor model only
Qty: 1
Qty: 2
*Refer to pp. 10 and 38.
Back
Side
Front
Side
Top
Boom
Model Top Bottom Front Back Sides
540P Indoor*
12 in.
(305 mm)
12 in.
(305 mm)
4 in.**
(102 mm)
0.5 in.
(13 mm)
3 in.
(76 mm)
540P Outdoor
36 in.
(914 mm)
12 in.
(305 mm)
24 in.
(610 mm)
0.5 in.
(13 mm)
3 in.
(76 mm)
*Standard indoor installations and direct-vent indoor installations have the same clearances.
**24 inches (610 mm) recommended for maintenance.
Maintain all clearances around the water heater.
Failure to do so could create a fire hazard, potentially
leading to death, serious injury, and/or property
damage.
WARNING
100276687 (TM-RE43) 100282480
10 Page
Installaon
Installaon Manual
3. Neutralizer kit: 100112159 (TH-NT01)
The neutralizer assembly neutralizes the condensate (acidic water) that forms in the
secondary heat exchanger of the water heater. (Refer to pp. 35 and 36.)
The temperature remote controller has
the following features:
• Adjusts set water temperature
• Controls the pump operation
• Works as a diagnostic tool
• provides a concise error code whenever there is a problem
with the unit.
1. Temperature remote controller:
100276687 (TM-RE43)
5. 3" PVC concentric termination: 100112163 (TH-CVPVC33)
Used when terminating direct-vent (sealed combustion)
systems, with Indoor models that require a 3 in. intake and a 3
in. exhaust.
2. Pipe cover:
100112718 (TH-PC03)
4. Sidewall vent terminator (Hood) and Wall thimble:
They are used when venting out through the wall. These terminations are special stainless steel vents
for gas appliances and are UL listed as Category II, III and IV. For different wall thicknesses, there
are two ranges of lengths available. (Refer to the NovaVent brochure for details.) Install these vent
terminations in accordance with their installation instructions and any applicable local codes.
Covering wall thicknesses Part#
Terminator Hood 100112419
Wall Thimble 4 - 7 in. (102 - 178 mm) 100112732
Wall Thimble 5 - 10 in. (123 - 254 mm) 100112733
Termination + Thimble 4 - 7 in. (102 - 178 mm) 100112424
Termination + Thimble 5 - 10 in. (123 - 254 mm) 100112425
Wall Thimble
Terminator Hood
6. Non-return valve for common venting : 100113130
It is a must-have item for common
venting system. It prevents
the escape of combustion gas
through non-operating appliances.
(Refer to pp. 26 and 27.)
This concentric termination provides the convenience of only having to make one penetration through a
sidewall instead of two separate penetrations for the intake and exhaust piping. The termination includes
a bird screen, restricting small animals, pests, and foreign objects from entering into the vent system.
(Refer to p.19.)
The pipe cover
protects the
plumbing pipes to
the water heater
from unexpected
adjustments. This
pipe cover is fixed to
the bottom of the water heater,
which hides the plumbing and
improves the visual aspects of the
whole installation for the water
heater.
Refer to pp. 50 to 59 for more information.
See the Troubleshooting Section (pp. 64 to 69) for information
on possible error codes.
7. 4" PVC Adapter: 100113129
This adapter transitions
from the Non-return valve
outlet to 4" schedule 40
PVC pipe.
11 Page
WARNING FOR INSTALLATIONS
FOR YOUR SAFETY, READ BEFORE INSTALLATION:
Do not install the heater where water, debris or
flammable vapors may get into the flue terminal.
This may cause damage to the heater and void the
warranty.
Do not have the vent terminal pointing toward
any opening into a building. Do not locate your
heater in a pit or location where gas and water
can accumulate.
Do not install this water heater under an
overhang less than 3 ft (914 mm) from its top
or eaves. The area under an overhang must be
open to three sides (Outdoor model only).
Do not install next to a dryer or any source
of airborne debris that can be trapped inside
the combustion chamber, unless the system is
direct-vented.
Prohibited
Prohibited
3 ft
(914 mm)
Installaon
Installaon Manual
Vent termination must be at least 2 ft (610 mm)
away from an inside corner for both outdoor
installation and direct-vent installation.
Inside
Corner
2 ft
(610 mm)
USA: 1 (30 cm) min.
Canada: 3 (91 cm) min.
USA: 1 (30 cm) min.
Canada: 3 (91 cm) min.
USA: 1 (30 cm) min.
Canada: 3 (91 cm) min.
USA: 12 in. (30 cm) above grade and
above ancipated snow level
Canada: 12 in. (30 cm) above grade
Ancipated snow level
Ensure that you meet the minimum clearances
shown below for a direct vent termination:
12 Page
HIGH-ALTITUDE INSTALLATIONS
Check the elevation where your water heater is installed. Set DIP switches shown in the table below
depending on the altitude.
WARNING
• To adjust high altitude settings, adjust only the No. 2, No. 3, and No. 4
DIP switches in the MIDDLE bank of DIP switches. (See below.) DO NOT
adjust the other DIP switches.
• Turn off the power supply to the water heater before changing the DIP
switch settings.
• Failure to observe these warnings could lead to carbon monoxide
poisoning or death.
Installaon
Installaon Manual
NOTE: The dark squares indicate the correct DIP switch positions.
Indoor model
0 to 2,000 ft
(0 to 610 m)
(DEFAULT)
2,000 to
3,000 ft
(611 to 914 m)
3,000 to
5,000 ft
(915 to 1,524 m)
5,000 to
7,500 ft
(1,525 to 2,286 m)
7,500 to
10,100 ft
(2,287 to 3,078 m)
Middle bank of DIP
switches
1 2 3 4 5 6
ON
No. 2 : OFF
No. 3 : OFF
No. 4 : OFF
1 2 3 4 5 6
ON
No. 2 : OFF
No. 3 : ON
No. 4 : OFF
1 2 3 4 5 6
ON
No. 2 : OFF
No. 3 : OFF
No. 4 : ON
1 2 3 4 5 6
ON
No. 2 : OFF
No. 3 : ON
No. 4 : ON
1 2 3 4 5 6
ON
No. 2 : ON
No. 3 : ON
No. 4 : ON
Altitude
DIP switches
Installation altitude
The maximum certified
or allowable installed
altitude is 10,100 ft
(3,078 m) for indoor
model and 6,000 ft
(1,829 m) for outdoor
model.
Outdoor model
0 to 2,000 ft
(0 to 610 m)
(DEFAULT)
2,000 to
4,000 ft
(611 to 1,219 m)
4,000 to
6,000 ft
(1,220 to 1,829 m)
Middle bank of DIP
switches
1 2 3 4 5 6
ON
No. 2 : OFF
No. 3 : OFF
No. 4 : OFF
1 2 3 4 5 6
ON
No. 2 : OFF
No. 3 : OFF
No. 4 : ON
1 2 3 4 5 6
ON
No. 2 : ON
No. 3 : OFF
No. 4 : ON
Altitude
DIP switches
Middle bank of DIP switches
Upper bank of DIP switches
Lower bank of DIP switches
13 Page
VENTING INSTRUCTIONS
540P Indoor model
-General-
WARNING
• Improper venting of this appliance can result in excessive levels of carbon
monoxide which can result in severe personal injury or death.
• Improper installation can cause nausea or asphyxiation, severe injury or death
from carbon monoxide and flue gases poisoning. Improper installation will void
product warranty.
• When installing the vent system, all applicable national and local codes must be
followed. If you install thimbles, fire stops or other protective devices and they
penetrate any combustible or noncombustible construction, be sure to follow
all applicable national and local codes.
The Indoor model must be vented in accordance with the section “Venting of Equipment" of the current
edition of the National Fuel Gas Code: ANSI Z223.1/NFPA 54 in the United States and/or Section 8 of the
B149.1 Natural Gas and Propane Installation Code in Canada, as well as applicable local building codes.
The use of venting materials approved for Category III/IV appliances is recommended whenever possible.
However, the Indoor model may also be vented with plastic pipe materials such as ABS, PVC (solid core),
CPVC (solid core), or polypropylene. For details, please refer to the Exhaust Vent (ABS, PVC, CPVC, or
Polypropylene Vent) Section on p. 18. Vent installations in Canada which utilize plastic vent systems must
use venting that complies with ULC S636.
General rules for venting water heaters:
• Place the water heater as close as possible to the vent termination.
• The vent collar of the water heater must be fastened directly to an unobstructed vent pipe.
• Do not weld the vent pipe to the water heater’s vent collar.
• Do not cut or alter the vent collar of the unit.
• The vent must be easily removable from the top of the water heater for normal service and inspection of
the unit.
• The water heater vent must not be connected to any other gas appliance or vent stack except an approved
common-venting system. Refer to pp. 26 and 27.
• Avoid using an oversized vent pipe or using extremely long runs of the pipe unless it is part of an approved
common vent system.
• Air supply pipe can be made of ABS, PVC (solid core), CPVC (solid core), polypropylene, corrugated stainless
steel, or Category lll/IV stainless steel. Regarding exhaust pipe, refer to pp. 18 and 23.
• Use of cellular core PVC (ASTM F891), cellular core CPVC, or Radel® (polyphenylsulfone) in nonmetallic
venting systems is prohibited. Covering non-metallic vent pipe and fittings with thermal insulation is
prohibited.
• Sidewall venting is recommended for the Indoor model. Vertical venting (roof termination) is acceptable.
• The manufacturer recommends running the exhaust vent and the intake pipe as parallel as possible.
• For rooftop venting, a rain cap or other form of termination that prevents rain water from entering into
the water heater must be installed.
• Do not terminate vent into a chimney. If the vent must go through the chimney, the vent must run all the
way through the chimney with approved vent pipe.
• The water heater shall not be connected to a chimney flue serving a separate appliance, designed to burn
solid fuel.
General rules for vent terminations:
• Avoid locating the water heater vent termination near any air intake devices. These fans can pick up the
exhaust flue products from the water heater and return them to the building. This can create a health
hazard.
• Locate the vent termination so that it cannot be blocked by any debris, at any time. Most codes require
that the termination be at least 12 in (305 mm) above grade and anticipated snow level, but the installer
may determine if it should be higher depending on the job site condition and applicable codes.
• A proper sidewall termination is recommended when the water heater is vented through a sidewall.
• Regarding the clearances from the exhaust termination to the air inlet or opening, refer to pp. 28 to 30.
Installaon
Installaon Manual
14 Page
-Combuson air supply-
• The guidelines in this section apply to installations within the United States. All
U.S. installations must conform to the National Fuel Gas Code, ANSI Z223.1/NFPA
54 (current edition) and local codes.
• Canadian requirements differ from the guidelines in this section. In Canada,
follow the requirements of B149.1 (Natural Gas and Propane Installation Code,
current edition) as well as local and provincial codes. Contact your local code
enforcement agency for direction.
NOTICE
This gas water heater requires an adequate source of clean air for combustion and
ventilation. Without sufficient air, your water heater may not operate properly and
may emit excessive and abnormal amounts of carbon monoxide which may result
in carbon monoxide poisoning or death.
WARNING
Before installing the water heater, you must determine the amount of air needed to supply this water
heater and any other gas appliances in the same area and provide adequate air for combuson and ven-
laon. Consult a qualied person if you’re unsure of the proper way to supply air to your water heater.
Check for Chemicals:
Air for combuson and venlaon must be clean and free of corrosive chemicals. If corrosive chemicals,
such as sulfur, ourine, or chlorine are present, the water heater must be direct vented. Failure due to
these corrosive chemicals is not covered by the warranty.
WARNING!
In all cases, ensure that corrosive chemicals are not present at the air intake. Presence of such chemicals
at the air intake could result in death, personal injury, or property damage. Examples of locaons that
require outside air due to chemicals include:
• Beauty salons
• Photo processing labs
• Indoor pools
• Laundry, hobby, or cra rooms
• Chemical storage areas
Products such as aerosol sprays, detergents, bleaches, cleaning solvents, gasoline, air fresheners, paint and
varnish removers, and refrigerants should not be stored or used near the water heater.
Does your installation space have sufficient combustion air?
Venlaon with outside air is recommended for all installaons. Even if the water heater is installed in a
large, open room inside the house, outdoor air is usually needed because modern homes are very ghtly
sealed and oen do not supply enough air to the water heater. However, when installed in a large indoor
space, it may be possible to provide enough air without outside venlaon. If you are unsure if your
installaon locaon has enough venlaon, contact your local gas ulity company or code ocials for a
safety inspecon or direct vent the water heater
The following instrucons will help determine if it may be possible to install the water heater without
outside venlaon.
Calculate total BTU/h rang of all appliances.
To calculate the combuson air and venlaon required, add up the total BTU/h rangs of all gas burn-
ing appliances (e.g., water heaters, furnaces, clothes dryers) in the same area. Do not include appliances
that are direct vented. Refer to the following example.
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Installaon Manual
15 Page
Your water heater’s BTU/h rating is on the rating plate. The BTU/h ratings should be on the other
appliances’ rating plates. If you have trouble determining the BTU/h ratings, contact the manufacturer
or have a qualified person determine the ventilation requirements.
NOTICE: If you are replacing your old water heater with one that has a higher BTU/h rang, the amount of
venlaon required may be greater.
Gas Burning Appliance BTU/h Rang
Gas Water Heater 199,000
Furnace 75,000
Dryer 20,000
Total 294,000
Example:
Gas Burning Appliance BTU/h Rang
Gas Water Heater
Total
Your
appliances:
Calculate the air volume of the room
Air requirements depend on the size of the room.
Room Volume (
3
) = Floor Area (
2
) X Ceiling Height ()
If there are large objects in the room (e.g., refrigerator, furnace, car), subtract their volume from the vol-
ume of the room to get a beer esmate of the air available.
Air Volume = Room Volume - Object Volume
NOTE: Adjoining rooms with permanently opened doorways can be counted as part of the calculaon.
Calculate required air volume
A water heater installed in an unconned ac, garage, or space requires that the space be at least 50
3
(1.42 m
3
) per 1,000 BTU/h of the total input for all gas burning appliances in the same area.
Required Air Volume (
3
) =Total Appliance Energy Rang (btu/h) X 50
3
/ 1000 (btu/h)
Example:
(294,000 / 1000) x 50 = 14,700
3
If the air volume of the room is less than the required air volume, you must direct vent the water heater
or provide permanent outside air openings that draw in sucient air. Go to “Install with outside venla-
on” if you want to provide combuson air with outside venlaon.
If the air volume of the room is greater than the required air volume, it may be possible to install the
water heater without outside venlaon. However, be sure to consider the eects of exhaust fans.
Exhaust fans can aect the amount of combuson air that is available in your home. Appliances such
as furnaces, whole house fans, and clothes dryers draw air out of your home. If they draw air out faster
than it can be replaced, your water heater may not have enough oxygen to re properly. Back-draing
may also result, which is when negave air pressure pulls air backwards through chimneys or appliance
vents. These events can cause unsasfactory water heater performance. The best soluon is to direct
vent the water heater or install an adequate number of make-up air vents. (See “Install with outside ven-
laon”.) For more informaon, consult a qualied technician or your local gas ulity.
Install with outside ventilation
Venlaon with outside air is recommended, and, for most installaons, is needed. There may be exisng
venlaon that is adequate, or you may need to add more venlaon.
Supplying outside air to the water heater typically requires two openings. One opening must be within 12 in
(305 mm) from the oor and the second opening must be within 12 in (305 mm) from the ceiling. Although a
single opening is not preferred, you may use a single opening to outside air if the minimum free area is sized
according to Table 1. Two openings must be used when venlang with air from another room.
The outside air can be taken from a crawl space or ac open to the outdoors and adequately venlated.
You may use vercal or horizontal ducts.
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16 Page
Determine type of ventilation
There are several types of venlaon that can be used. The various opons are listed below. See also the
illustraons on the next page.
1. Direct to outdoors
2. Vercal ducts
3. Horizontal ducts
4. Single opening (not recommended; must be at least 100 in
2
(645 cm
2
) . Not appropriate for conned spac-
es smaller than 50
3
(1.42 m
3
) per 1,000 BTU/h or when geng air from another room.)
5. From a larger room inside the house (not recommended – refer to "Calculate the air volume of the room"
above to determine if the combined volume of the rooms may be adequate).
Determine minimum free area required for each vent opening
The size of the vent openings depends on the total BTU/h rang of all appliances in the space (use your calculaon
from “Before beginning”) and the type of vent used. Table 1 provides the minimum free area for each vent opening
depending on the type of venlaon.
Calculate minimum size of vent openings and ducts
The vent cross-seconal area needed to provide the free area depends on the covering on the vent openings. Typical
vents use louvers or grilles to protect the opening. The louver or grill itself blocks some of the free area, so the open-
ing may need to be larger to meet the minimum free area requirements.
Use the following formula to calculate the required cross-seconal area:
Cross-seconal area = minimum free area required ÷ percent free area of covering (in decimals – e.g., 60 % = 0.6)
For example, an installaon area that requires openings with 100 in
2
(645 cm
2
) of free area would need
134 in
2
(865 cm
2
) openings if using metal louvers rated at 75% free area (100 in
2
÷ 0.75 = 134 in
2
).
If you do not know the % free area for your louver or grill, use the following values:
• For wood louvers or grilles: 25%
• For metal louvers or grilles: 75%
Follow these rules to ensure that vents and ducts provide adequate air ow:
• Each vent opening must be no smaller than 100 in
2
(645 cm
2
).
• Ducts must have the same cross-seconal area as free area of the opening.
• Rectangular ducts must have a minimum dimension of no less than 3 in (76 mm).
• All screens must have mesh ¼” or larger.
• Moveable louvers must be locked open or interconnected with the equipment so that they open automa-
cally during operaon.
• Keep louvers and grills clean and free of debris or other obstrucons.
Check that air source is clean and free of chemicals
Air for combuson and venlaon must be clean and free of corrosive or ammable chemicals. A failure due to cor-
rosive chemicals in the air is not covered by the warranty. Combuson air must be free of acid-forming chemicals such
as sulfur, uorine, and chlorine. Be sure that air at the vent inlets is free of such chemicals.
See graphics on next page.
Table 1
Minimum Free Area of Permanent Openings for Venlaon and Combuson Air Supply – Air from outdoor or
indoor spaces.
Based on the total BTU/h input rang for all gas burning appliances within a conned space.
Opening Source Minimum Free Area
Direct to outdoors*
1 in
2
(6.5 cm
2
) per 4,000 BTU/hr (see Figure 1, 2)
Vercal ducts
1 in
2
(6.5 cm
2
) per 4,000 BTU/hr (see Figure 3)
Horizontal ducts
1 in
2
(6.5 cm
2
) per 2,000 BTU/hr (see Figure 4)
Single Opening
1 in
2
(6.5 cm
2
) per 3,000 BTU/hr (see Figure 5)
Two permanent openings
to another room**
1 in
2
(6.5 cm
2
) per 1,000 Btu/hr (see Figure 6)
Opening: 100 in
2
(645 cm
2
) Min
Minimum dimension of air openings:
no less than 3 in (76 mm)
*These openings connect directly with the outdoors through a venlated ac, a venlated crawl space, or through
an outside wall.
**United States: For direcon on combining spaces in dierent stories within the structure, refer to the current edi-
on of the Naonal Fuel Gas Code ANSI Z223.1/NFPA 54. In Canada, contact your local code enforcement agency for
direcon.
Installaon
Installaon Manual
17 Page
Combuson air supply opons
Gable vent
to outdoors
Install above
insulaon
Outlet air to
ac 1 in
2
(6.5 cm
2
)
per 4,000 btu/h
Inlet air from
the crawl space
Open foundaon vent
Confined
Space
Alternate
Air Inlet
1 in
2
(6.5 cm
2
)
per 4,000 btu/h
Figure 1 - Direct to outdoors openings
Figure 3 - Vercal duct openings
Outlet air to
ac 1 in
2
(6.5 cm
2
)
per 4,000 btu/h
Inlet air duct
1 in
2
(6.5 cm
2
)
per 4,000 btu/h
Confined
Space
12” (305 mm)
maximum
Gable vent
to outdoors
Install above
insulaon
Figure 5 - SIngle opening
Confined
Space
1 in
2
(6.5 cm
2
)
per 3,000 btu/h
Alternave
Opening
Locaon
Figure 6 - Two permanent openings
Two permanent
Openings
1 in
2
per
1,000 btu/h
12” (305 mm)
maximum
12” (305 mm)
maximum
Confined
Space
Figure 4 - Horizontal duct openings
1 in
2
(6.5 cm
2
)
per 2,000 btu/h
Confined
Space
Outlet
Inlet
Outdoor
Air Ducts
1 in
2
(6.5 cm
2
)
per 2,000 btu/h
Figure 2 - Direct to outdoors openings
Two permanent openings
Two permanent
Openings
1 in
2
(6.5 cm
2
)
per 4,000 btu/h
12” (305 mm)
maximum
12” (305 mm)
maximum
Confined
Space
Installaon
Installaon Manual
18 Page
-Exhaust vent (ABS, PVC, CPVC, or polypropylene vent)-
The Indoor model can be vented with ABS, PVC, CPVC, or polypropylene (temperature rated up to
149 °F). Vent material certified to ULC S636 standards is recommended in the USA. In Canada, plastic
venting must be certified to ULC S636 standards.
• The maximum length of exhaust vent piping must not exceed 70 ft (21.3 m) for 3” (76 mm)
venting, which depends on the elevation where the water heater is installed, and 100 ft (30.5 m)
for 4” (102 mm) venting (deducting 5 ft (1.5 m) for each elbow used in the venting system). Do
not use more than 5 elbows. See the table below.
• When the horizontal vent run exceeds 5 ft (1.5 m), support the vent run at 3 ft (0.9 m) intervals
with overhead hangers.
Installaon
Installaon Manual
Item Material United States Canada
Exhaust pipe and
Fittings
Schedule 40 PVC ANSI/ASTM D1785
ULC S636 Certified
Materials Only
PVC-DWV ANSI/ASTM D2665
Schedule 40 CPVC ANSI/ASTM F441
Schedule 40 ABS-DWV ANSI/ASTM D2661
Polypropylene UL-1738
Pipe Cement/Primer
PVC ANSI/ASTM D2564
CPVC ANSI/ASTM F493
ABS ANSI/ASTM D2235
Use of cellular core PVC (ASTM F891), cellular core CPVC, or Radel® (polyphenylsulfone) in
non-metallic venting systems is prohibited.
Covering non-metallic vent pipe and fittings with thermal insulation is prohibited.
Diameter Max. No. of Elbows Max. Vertical and Horizontal (Total) Vent Length
3 in. 5 70 ft (21.3 m)
4 in. 5 100 ft (30.5 m)
*For each elbow added, deduct 5 ft (1.5 m) from max. vent length.
No. of Elbows
Max. Vertical or Horizontal (Total) Vent Length
3" venting 4" venting
0 to 3,000 ft
(0 to 914 m)
3,001 to 6,000 ft
(915 to 1,829 m)
6,001 to 10,100 ft
(1,830 to 3,078 m)
0 to 10,100 ft
(0 to 3,078 m)
0 70 ft (21.3 m) 40 ft (12.2 m) 25 ft (7.6 m) 100 ft (30.5 m)
1 65 ft (19.8 m) 35 ft (10.7 m) 20 ft (6.1 m) 95 ft (29.0 m)
2 60 ft (18.3 m) 30 ft (9.1 m) 15 ft (4.6 m) 90 ft (27.4 m)
3 55 ft (16.8 m) 25 ft (7.6 m) 10 ft (3.0 m) 85 ft (25.9 m)
4 50 ft (15.2 m) 20 ft (6.1 m) N/A 80 ft (24.4 m)
5 45 ft (13.7 m) N/A N/A 75 ft (22.9 m)
Excludes vent terminators, termination elbows, or rain caps.
For details on the vent connection, refer to pp. 19 to 22.
19 Page
Installaon
Installaon Manual
-DIP switch settings for vent length-
Typical installaons using PVC, CPVC, ABS, or polypropylene vent
<Two-pipe, direct-vent installaon>
Vercal Installaon
Horizontal Installaon
Roof
Wall
Hanger
Hanger
Roof
ashing
Fire stop
Connect between exhaust vent collar and
piping. See the instrucons on p. 20.
For details of the optional items, refer to the Installation manual for each optional item.
WARNING
• To adjust vent length, adjust only the No. 3 and No. 4 DIP switches in the
LOWER bank of DIP switches. (See below.) DO NOT adjust the other DIP
switches.
• Turn off the power supply to the water heater before changing the DIP
switch settings.
• Failure to observe these warnings could lead to carbon monoxide poison-
ing or death.
*PVC concentric termination (100112163) installation is applied to the DIP switch settings of 3" vent-
ing. (Refer to p. 10.)
Set DIP switches shown in the table below depending on the vent diameter
and length.
DIP switch settings : Two-pipe, Direct vent installations
Vent diameter
3" venting* 4" venting
5 to 20 ft
(1.5 to 6.1 m)
(DEFAULT)
21 to 40 ft
(6.2 to 12.2 m)
41 to 70 ft
(12.3 to 21.3 m)
5 to 50 ft
(1.5 to 15.2 m)
(DEFAULT)
51 to 100 ft
(15.3 to 30.5 m)
Lower bank
of
DIP switches
1 2 3 4 5 6 7 8
ON
No. 3 : O N
No. 4 : OFF
1 2 3 4 5 6 7 8
ON
No. 3 : OFF
No. 4 : OFF
1 2 3 4 5 6 7 8
ON
No. 3 : O N
No. 4 : O N
1 2 3 4 5 6 7 8
ON
No. 3 : O N
No. 4 : OFF
1 2 3 4 5 6 7 8
ON
No. 3 : OFF
No. 4 : OFF
Vent
length
DIP
switches
Lower bank of
DIP switches
20 Page
Installaon
Installaon Manual
Horizontal Installaon Vercal Installaon
<Single pipe with room-air intake installaon>
Roof
ashing
Roof
Elbow
Fire stop
Connect between exhaust vent collar and piping.
See the instrucons on p. 21.
Elbow
Wall
Hanger
For details of the optional items, refer to the Installation manual for each Optional item.
WARNING
• To adjust vent length, adjust only the No. 3 and No. 4 DIP switches in the
LOWER bank of DIP switches. (Refer to the following page.) DO NOT adjust
the other DIP switches.
• Turn off the power supply to the water heater before changing the DIP
switch settings.
• Failure to observe these warnings could lead to carbon monoxide poison-
ing or death.
1. Insert no more than 12" (305 mm) of 3" straight
pipe into the exhaust/intake vent collar with 3"
adapter.
2. Connect 3" x 4" increasers to straight pipes.
3. Connect 4" straight pipes to the increasers.
<How to install intake and exhaust venting (two-pipe, direct-vent) with the indoor models>
4" vent connecon for PVC/CPVC venng only
• PVC adapter will accept 3" straight pipe.
3" vent connecon for PVC/CPVC venng only
Exhaust vent collar
with 3" adapter*
(Female)
Intake vent collar with
3" adapter* (Female)
3" straight pipe
3" straight pipe
2. Connect 3" straight pipes directly on the exhaust
and intake vent collar of the water heater.
1. Remove each screw from 3" adapter to detach the
adapters from each vent collar.
3" vent connecon for other venng
without 3" PVC adapter
Exhaust vent collar
(Female)
Intake vent collar
(Female)
3" straight pipe
3" straight pipe
*3" PVC adapters are not
approved for use in Canada.
NOTICE
Intake vent collar with
3" adapter* (Female)
Exhaust vent collar
with 3" adapter*
(Female)
3" x 4" increaser
3" x 4" increaser
4"straight pipe
3"straight pipe
no more than 12"
(305 mm)
4" straight pipe
3" straight pipe
no more than 12"
(305 mm)
Exhaust vent collar
(Female)
Intake vent collar
(Female)
3" adapter*
3" adapter*
Screws
21 Page
Installaon
Installaon Manual
DIP switch settings: Single vent pipe installations
Vent diameter
3" venting 4" venting
5 to 45 ft
(1.5 to 13.7 m)
(DEFAULT)
46 to 70 ft
(13.8 to 21.3 m)
5 to 50 ft
(1.5 to 15.2 m)
(DEFAULT)
51 to 100 ft
(15.3 to 30.5 m)
Lower bank
of
DIP switches
1 2 3 4 5 6 7 8
ON
No. 3 : O N
No. 4 : OFF
1 2 3 4 5 6 7 8
ON
No. 3 : OFF
No. 4 : OFF
1 2 3 4 5 6 7 8
ON
No. 3 : O N
No. 4 : OFF
1 2 3 4 5 6 7 8
ON
No. 3 : OFF
No. 4 : OFF
Vent
length
DIP
switches
Lower bank of
DIP switches
Set DIP switches shown in the table below depending on
the vent diameter and length.
1. Remove the screw from the 3" adapter on the
exhaust vent collar, then remove the adapter.
2. Connect spigot end of 3" street elbow into the
intake vent collar with 3" adapter. Be sure to insert
bird screen into the hub side.
3. Connect 3" straight pipe or appliance adapter to the
exhaust vent collar.
4" vent connecon for PVC/CPVC venng only
<How to install single vent with the indoor models>
1. Connect spigot end of 3" street elbow into the intake
vent collar with 3" adapter. Be sure to insert bird
screen into the hub side.
2. Connect 3" straight pipe into the exhaust vent collar
with 3" adapter.
3" vent connecon for other venng
-without 3" PVC adapter
1. Insert no more than 12" (305 mm) of 3"
straight pipe into the exhaust vent collar with
3" adapter.
2. Connect a 3" x 4" increaser into the 3" straight
pipe.
3. Connect 4" straight pipe into the increaser.
4. Connect spigot end of 3" street elbow into the
intake vent collar with 3" adapter. Be sure to
insert bird screen into the hub side.
Intake vent collar
with 3" adapter
(Female)
3" straight pipe or
Appliance adapter
Exhaust vent collar
(Female)
3" street elbow
with bird screen
Exhaust vent collar with
3" adapter (Female)
Intake vent collar
with 3" adapter
(Female)
3" street elbow
with bird screen
3" straight pipe
*3" PVC adapters are not
approved for use in Canada.
NOTICE
3" vent connecon for PVC/CPVC venng only
Exhaust vent collar
(Female)
Intake vent collar
with 3" adapter
(Female)
3" adapter*
Screw
Exhaust vent collar
with 3" adapter*
(Female)
3" x 4" increaser
4" straight pipe
3" straight pipe
no more than 12"
(305 mm)
Intake vent collar
with 3" adapter
(Female)
3" street elbow
with bird screen
22 Page
Installaon
Installaon Manual
CENTROTHERM PP VENTING (Polypropylene)
WARNING! Do not mix parts or fittings of different material types, and do not mix pipe, fittings, or
joining methods from different manufacturers. Combustion exhaust can contain carbon monoxide and
must be properly vented outside. Breathing abnormal amounts of carbon monoxide can result in seri-
ous injury or death.
Description
Centrotherm Part Number (Trade
Name InnoFlue)
4''/6'' x 39" (990 mm) Concentric Wall
ICWS4639
4'' Twin Pipe to 4''/6'' Concentric Adaptor
ICTC0446
4" x 87° Elbow
ISEL0487
100 mm to 4" Increaser
ISIA10004
4" x 12" (305 mm) Vent Length
ISVL041
4" x 24" (610 mm) Vent Length
ISVL042
4'' x 36'' (914 mm) Vent Length
ISVL043
4" x 72" (1,829 mm) Vent Length
ISVL046
4" Horizontal Drain Tee
ISHDT04
3''/5'' x 13'' (330 mm) Concentric Wall Termination SS
ICWS3513
3'' Twin Pipe to 3''/5'' Concentric Adaptor
ICTC0335
3" x 87 Elbow
ISEL0387
3" x 12" (305 mm) Vent Length
ISVL031
3" x 24" (610 mm) Vent Length
ISVL032
3" x 36'' (914 mm) Vent Length
ISVL033
3" x 72'' (1,829 mm) Vent Length
ISVL036
3" Horizontal Drain Tee
ISHDT03
23 Page
Installaon
Installaon Manual
Typical installaons using stainless steel vents
Vercal Installaon
Roof
Roof ashing
Fire stop
Rain cap
Horizontal Installaon
Sidewall vent
terminaon
Wall
Hanger
Hanger
-Exhaust vent (Stainless steel vent)-
This is a Category IV appliance and must be vented accordingly. The vent system must be sealed airtight.
All seams and joints without gaskets must be sealed with high heat resistant silicone sealant or UL listed
aluminum adhesive tape having a minimum temperature rating of 160 °F (71 °C). For best results, a vent
system should be as short and straight as possible.
• The Indoor model is a Category IV appliance and must be vented accordingly with any 4” (106
mm) vent approved for use with Category III/IV or Special BH type gas vent.
• The manufacturer recommends the NovaVent line. However, the following are also UL listed
manufacturers: ProTech Systems Inc. (FasNSeal), Metal-Fab Inc., and Heat-Fab Inc. (Saf-T Vent).
• Follow the vent pipe manufacturer’s instructions when installing the vent pipe.
• The maximum length of exhaust vent piping must not exceed 100 ft (30.5 m) (deducting 5 ft (1.5
m) for each elbow used in the venting system). Do not use more than 5 elbows.
• When the horizontal vent run exceeds 5 ft (1.5 m), support the vent run at 3 ft (0.9 m) intervals
with overhead hangers.
Diameter Max. No. of Elbows Max. Vertical and Horizontal (Total) Vent Length
4 in. 5 100 ft (30.5 m)
*For each elbow added, deduct 5 ft (1.5 m) from max. vent length.
Excludes vent terminators, termination elbows, or rain caps.
No. of Elbows Max. Vertical or Horizontal Vent Length
0 100 ft (30.5 m)
1 95 ft (29.0 m)
2 90 ft (27.4 m)
3 85 ft (25.9 m)
4 80 ft (24.4 m)
5 75 ft (22.9 m)
-DIP switch settings for vent length-
24 Page
Installaon
Installaon Manual
<How to install stainless steel vent with the indoor model>
WARNING
• Regarding the clearances from the exhaust terminal to the air inlet or opening, refer
to pp. 28 to 30.
• Follow all vent system manufacturer’s instructions and all local codes.
• Use 4" Category III/IV approved or Special BH, single or double wall stainless steel vent
pipe.
• Do not mix parts or fittings of different material types, and do not mix pipe, fittings,
or joining methods from different manufacturers. Combustion exhaust can contain
carbon monoxide and must be properly vented outside. Breathing abnormal
amounts of carbon monoxide can result in serious injury or death.
Set DIP switches shown in the table below depending on the vent diameter and length.
DIP switch settings :
Single pipe and Direct vent installations
Vent diameter
4" venting
5 to 50 ft
(1.5 to 15.2 m)
(DEFAULT)
51 to 100 ft
(15.3 to 30.5 m)
Lower bank
of
DIP switches
1 2 3 4 5 6 7 8
ON
No. 3 : O N
No. 4 : OFF
1 2 3 4 5 6 7 8
ON
No. 3 : OFF
No. 4 : OFF
Vent
length
DIP
switches
Lower bank of DIP switches
WARNING
• To adjust vent length, adjust only the No. 3 and No. 4 DIP switches in the
LOWER bank of DIP switches. (See below.) DO NOT adjust the other DIP
switches.
• Turn off the power supply to the water heater before changing the DIP
switch settings.
• Failure to observe these warnings could lead to carbon monoxide poison-
ing or death.
4" vent connecon for direct-vent installaon
4" stainless steel
vent straight pipe or
appliance adapter
Exhaust vent collar
of the Indoor
models (Female)
Intake vent
collar (Female)
4" stainless steel
vent straight pipe
or appliance adapter
Exhaust vent collar
of the Indoor models
(Female)
4" stainless steel
vent straight pipe or
appliance adapter
Intake vent
collar (Female)
4" elbow with bird
screen
1. Connect a 4" stainless steel vent straight pipes to the
exhaust vent collar.
2. Connect a 4" elbow to the intake vent collar.
• Connect 4" stainless steel vent straight pipes to the
exhaust/intake vent collar.
4" vent connecon for single vent installaon
*USA indoor models only: Before installation, remove the
screws from the 3" adapters and remove the adapters from
each vent collar.
Exhaust vent
collar (Female)
Intake vent collar
(Female)
3" adapter*
3" adapter*
Screw
25 Page
Approved Category IV, Single Wall, Venting Suppliers and Part Numbers
WARNING! Do not mix parts or fittings of different material types, and do not mix pipe, fittings, or
joining methods from different manufacturers. Combustion exhaust can contain carbon monoxide and
must be properly vented outside. Breathing abnormal amounts of carbon monoxide can result in seri-
ous injury or death.
Description
Heater Vent
Kits
Z-FLEX®
NovaVENT™ Z-VENT™
4" Straight pipe - 6" (152 mm) length
100112407 2NVP4.5 2SVEPWCF0406
4" Straight pipe - 12" (305 mm) length
100112406 2NVP41 2SVEPWCF0401
4" Straight pipe - 24" (610 mm) length
100112404 2NVP42 2SVEPWCF0402
4" Straight pipe - 36" (914 mm) length
100112403 2NVP43 2SVEPWCF0403
4" Straight pipe - 48" (1,219 mm) length
100112402 2NVP44 2SVEPWCF0404
4" Adjustable straight pipe -
10"-18" (254 - 457 mm) adjustability
100112405 2NVAL4 2SVSPA04
4" 45 degree elbow
100112401 2NVE445 2SVEEWCF0445
4" 90 degree elbow
100112400 2NVE490 2SVEEWCF0490
4" Sidewall termination (4" Termination Hood)
100112419 2NVTH4 2SVSHTX04
4" Vent termination tee
100112547 2NVTT4 2SVSTTF04
4" Rain Cap
100112415 2NVRC4 2SVSRCF04
4" Extreme weather rain cap
100112548 2NVWC4 2SVSHRC04
4" Horizontal drain tee
100112414 2NVHD4 2SVEDWCF04
4" Vertical drain tee
100112413 2NVVD4 2SVEVDP04
4" wall thimble length
4"-7" (102 - 178 mm) wall thickness
100112732 2NVWT4 2SVSWTF04
4" wall thimble length
5"-10" (127 - 254 mm) wall thickness
100112733 2NVWT4L 2SVSWTEF04
4" 3-in-1 adaptor
(F-F adaptor, condensate drain, & back-flow preventer)
100112549 2NVBFA4 2SVBFDPA04
4" F-F adaptor
100112399 2NVAFF4 2SVEEWCF0445
4" Backflow preventer w/F-F adaptor
100112416 2NVBFU4 2ZVB04
4" exhaust/3" intake DV concentric termination
- 5"-10" (127 - 254 mm) adjustability
100112550 2NVHTC43S 2SVSHTC43S
4" exhaust/3" intake DV concentric termination
- 12"-18" (305 - 457 mm) adjustability
100112551 2NVHTC43 2SVSHTC43
4" Sidewall termination, adjustable pipe
100187853 2NVBV4 n/a
4" Wall Thimble, 3"-6"(76 - 152 mm) wall thickness
100187852 2NVBT4 n/a
4" exhaust/3" intake concentric termination
- 5" to 10" (127 - 254 mm) adjustability
100112550 2NVHTC43S 2SVSHTC43S
4" exhaust/3" intake concentric termination
- 12" to 18" (305 - 457 mm) adjustability
100112551 2NVHTC43 2SVSHTC43
4" exhaust/4" intake concentric termination
- 5" to 10" (127 - 254 mm) adjustability
100112552 2NVHTC44S 2SVSHTC04S
4" exhaust/4" intake concentric termination
- 12" to 18" (305 - 457 mm) adjustability
100112553 2NVHTC44S 2SVSHTC04
4" Flat roof flashing
100112412 2NVFF4 2SVSSCF04
4" Angled roof flashing
100112411 2NVAF4 2SVSADJF04
Storm collar
100112410 2NVSC4 2SVSLSF04
Wall support
100112409 2NVSS41 2SVSWS04
Firestop support
100112408 2NVFS4 2SVSFSSF04
Installaon
Installaon Manual
26 Page
-Common-venng system-
The Indoor model can be vented together using the same exhaust and intake venting.
• Up to 8 water heaters can be common-vented together.
• A non-return valve (100113130) must be used for each water heater that is part of the system.
• The water heaters must all be direct-vented.
• The common-venting system shall be in accordance with the National Fuel Gas Code,
ANSI Z223.1/NFPA 54 and/or B149.1, Natural Gas and Propane Installation Code
(Current Editions), local codes, and the following manufacturer’s instructions.
• For common-venting pieces and components, the manufacturer recommends
Centrotherm's vent line.
Typical common-vent installaon examples
Only the above allowable models can be common-vented together.
Different models cannot be common-vented.
CAUTION
Allowable models for common-venting
240 Indoor, 340 Indoor, 540 Indoor, 540P Indoor, CT-199 Indoor
Installaon
Installaon Manual
Intake
wall
Exhaust
Roof
Condensate drain port
Non-Return Valve
Exhaust
wall
Roof
Intake
Non-Return Valve
Condensate drain port
Exhaust
Intake
wall
Roof
Non-Return Valve
Condensate drain port
NOTICE
For details on the installation of a common-vent system, please refer to "Common
Venting Tankless Gas Water Heaters." It is a manual which is available on the water
heater manufacturer's website.
27 Page
To determine the dimension of a common-venng system
Determine the vent diameter (D) and the total vent length based on the number of water
heaters installed. The total vent length (L) consists of the horizontal width (W) and the vercal
height (H). See the table below.
WARNING
• A Non-Return Valve must be installed for each water heater. This prevents
the escape of combustion gas through non-operating appliances.
• For detailed instructions on the common-venting system, refer to the
instructions that are packaged with the vent parts or web site.
NOTICE
• Regarding the clearances
between the exhaust
terminaon and the intake
terminaon, refer to pp. 28
to 30.
• Insert bird screen in
elbow terminals.
*Diameters of pipes are in accordance with Centrotherm's specifications.
**One elbow is equivalent to 5 ft (1.5 m) linear length, and the maximum number of elbows is 5.
Common-venting system
Vent
Diameter*
(D)
Max.
No. of
water
heaters
Max. Vertical and
Horizontal
(Total) Vent Length** (L)
DIP switch settings
540P Indoor
(Lower bank of
DIP switches)
4 in. 2 25 ft (7.6 m)
1 2 3 4 5 6 7 8
ON
No. 3 : ON
No. 4: OFF
5 in.
2 50 ft (15.2 m)
3 20 ft (6.1 m)
6 in.
2 100 ft (30.5 m)
3 75 ft (22.9 m)
4 50 ft (15.2 m
5 25 ft (7.6 m)
6 20 ft (6.1 m)
8 in.
3 100 ft (30.5 m)
4 100 ft (30.5 m)
5 85 ft (25.9 m)
6 65 ft (19.8 m)
7 50 ft (15.2 m)
8 41 ft (12.5 m)
10 in.
5 100 ft (30.5 m)
6 100 ft (30.5 m)
7 100 ft (30.5 m)
8 100 ft (30.5 m)
Installaon
Installaon Manual
•
•
•
For common-venting,
adjust only the No. 3
and No. 4 DIP switches
in the LOWER bank of
DIP switches. (Refer to
p.24 for the location of
the DIP switches.)
Turn off the power sup-
ply to the water heater
before changing the
DIP switch settings.
Failure to observe
these warnings could
lead to carbon
monoxide poisoning or
death.
WARNING
"H"
Intake
Exhaust
"D"
Elbow terminal
Elbow terminal
"W"
Non-Return Valve
• Total vent length (L)="H"+"W"+
(Number of Elbows X 5)
• Vent diameter="D"
28 Page
Installaon
Installaon Manual
-Vent terminaon clearances-
Canada Installations
1
US Installations
2
Direct vent and other than
direct vent
Direct vent
Other than
direct vent
A Clearance above grade, veranda, porch, deck, or balcony 1 ft (30 cm) 1 ft (30 cm)
B Clearance to window or door that may be opened 3 ft (91 cm)
1 ft
(30 cm)
4 ft (1.2 m) below or to
side of opening; 1 ft (30
cm) above opening
C Clearance to permanently closed window 0 0 0
D
Vertical clearance to ventilated soffit located above
the vent terminator within a horizontal distance of 2
feet (61cm) from the center line of the termination
3 ft (91 cm) 3 ft (91 cm) 3 ft (91 cm)
E Clearance to unventilated soffit 3 ft (91 cm) 3 ft (91 cm) 3 ft (91 cm)
F Clearance to outside corner 2 ft (61 cm) 2 ft (61 cm) 2 ft (61 cm)
G Clearance to inside corner 2 ft (61 cm) 2 ft (61 cm) 2 ft (61 cm)
H
Clearance to each side of center line extended
above meter/regulator assembly
3 ft (91 cm) * *
I Clearance to service regulator vent outlet
Above a regulator within 3
ft (91 cm) horizontally of the
vertical center line of the
regulator vent outlet to a
maximum vertical distance of
15 ft (4.5 m)
* *
J
Clearance to non-mechanical air supply inlet to
building or the combustion air inlet to any other
appliance.
3 ft (91 cm)
1 ft
(30 cm)
4 ft (1.2 m) below or to
side of opening; 1 ft (30
cm) above opening
K Clearance to mechanical air supply inlet 6 ft (183 cm)
3 ft (91 cm) above if within
10 ft (3 m) horizontally.
L
Clearance above paved sidewalk or paved driveway
located on public property
7 ft (213 cm)**
7 ft
(213 cm)
7 ft (213 cm)
M Clearance under veranda, porch deck, or balcony 1 ft (30 cm)***
1 ft
(30 cm)***
1 ft (30 cm)***
*Clearance in accordance with local installation codes and the requirements of the gas supplier.
**A vent shall not terminate directly above a sidewalk or paved driveway that is located between two single family dwellings
and serves both dwellings.
***Permitted only if veranda, porch, deck, or balcony is fully open on a minimum of two sides beneath the floor.
The vent for condensing water heaters shall not terminate:
1) over public walkways; or
2) near soffit vents or crawl space vents or other areas where condensate or vapor could create a nuisance or hazard or
cause property damage; or
3) where condensate vapor could cause damage or could be detrimental to the operation of regulators, relief valves, or
other equipment.
Notes:
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
H
D
E
L
B
V
V
V
V
B
F
C
B
B
B
V
V
V
V
V
X
X
A
J
M
Operable
Fixed
closed
Fixed
closed
Operable
B
Inside corner
detail
G
A
K
V
X
= Vent terminal
= Air supply inlet
= Area where the terminal
is not permied
Regulator/Gas meter
vent outlet
I
29 Page
Installaon
Installaon Manual
-Clearances for sidewall terminaons-
Multiple Sidewall Terminations
An exhaust termination must be at least
1 ft (305mm) away from another exhaust
termination. An exhaust termination must
also be at least 2 ft (610 mm) away from
an inside corner. (If the adjacent wall is less
than 2 ft (610 mm) of length, the minimum
required distance away from the inside
corner will be equal to the length of that
adjacent wall.)
Multiple DV Sidewall Terminations
A direct vent (DV) termination must be
at least 1 ft (305 mm) away from other
direct vent terminations.
A direct vent termination must also be at
least 2 ft (610 mm) away from an inside
corner. (If the adjacent wall is less than
2 ft (610 mm) of length, the minimum
required distance away from the inside
corner will be equal to the length of that
adjacent wall.)
Ancipated Snow level
Exhaust
Terminaon
2
(610 mm)
min.
1
(305 mm)
min.
1
(305 mm)
min.
Inside
corner
Inside
corner
Ancipated Snow level
2
(610 mm)
min.
1
(305 mm)
min.
1
(305 mm)
min.
Combined
intake and
exhaust
terminaon
For direct vent sidewall
terminations that use two
separate penetrations for
the intake and exhaust,
keep the termination
clearances shown in the
diagrams on the right.
Improper installation can result in carbon monoxide poisoning or death. Follow all local
and national codes in regards to proper termination clearances. In the absence of such
codes, the clearances below can be used as guidelines. Local codes supersede these
guidelines.
WARNING
1 ft (305 mm) min.
0.5 ft
(159 mm) min.
Exhaust
Intake
Exhaust
Intake
<Case 2>
1 ft (305 mm)
min.
0.5 ft
(159 mm) min.
0.5 ft
(159 mm)
min.
Exhaust
Intake
Exhaust
Intake
<Case 1>
Exhaust
termination
2 ft (610 mm)
min.
Exhaust and/or direct
vent sidewall terminations
should be at least 2 ft (610
mm) away from an opposite
surface/wall. Do not place
the termination directly in
front of an opening into a
building.
30 Page
Installaon Manual
Installaon
-Clearances for rooop terminaons-
Follow all local and national codes in regards to proper termination clearances. In the absence
of such codes, the clearances below must be met. Local codes supersede these clearances.
Failure to observe this warning may result in severe personal injury or death.
WARNING
• Exhaust terminations must be at least 1 ft (305 mm) away from any obstructions.
• Minimum spacing between multiple terminals:
• intake terminals: 1 ft (305 mm) spacing between each
• exhaust terminals: 1 ft (305 mm) spacing between each
• The exhaust termination must be a horizontal distance of at least 2 ft (610 mm) from a
wall or surface unless specified differently by local code.
• Failure to observe this warning may result in severe personal injury or death.
WARNING
3 ft (914 mm) min.
Exhaust gas
Intake air
1 ft
(305 mm) min.
1 ft
(305 mm) min.
Anticipated
snow level
Flat roof termination
Vercal wall
Ancipated snow level
1
(305 mm)
min.
1
(305 mm)
min.
2
(610 mm)
min.
2
(610 mm)
min.
1
(305 mm)
min.
1
(305 mm)
min.
1
(305 mm)
min.
1
(305 mm)
min.
3 (914 mm) min.
Exhaust gas
Exhaust gas
Intake air
Intake air
Multiple flat roof terminations
Canadian requirements differ from the guidelines in this section. In Canada, follow
the requirements of B149.1 (Natural Gas and Propane Installation Code, current
edition) as well as local and provincial codes. Contact your local code enforcement
agency for direction.
NOTICE
Exhaust gas
2 ft (610 mm) min.
Intake air
1 ft
(305 mm) min.
1 ft
(305
mm)
min.
1 ft
(305 mm)
min.
Anticipated
snow level
Angled roof termination
Exhaust
gas
Exhaust
gas
Intake air
Intake air
1
(305 mm)
min.
1
(305 mm)
min.
1
(305 mm)
min.
1
(305 mm)
min.
2 (610 mm) min.
Ancipated snow level
1
(305 mm)
min.
3 (914 mm) min.
Multiple angled roof terminations
31 Page
GAS SUPPLY AND GAS PIPE SIZING
-General-
• Check that the type of gas matches the rating plate first.
• Ensure that any and all gas regulators used are operating properly and
providing gas pressures within the specified range shown below. Excess gas
inlet pressure may cause serious accidents.
• Conversion of this unit from natural gas to propane or vice versa will void
all warranty. Contact your local distributor to get the correct unit for your
gas type. The manufacturer is not liable for any property and/or personal
damage resulting from gas conversions.
• Failure to observe these warnings could result in severe personal injury, carbon
monoxide poisoning, or death.
WARNING
• The minimum and maximum inlet gas pressures are:
Gas type Inlet gas pressure
Natural Gas Min 4.0” W.C. (1.00 kPa) – Max. 10.5” W.C. (2.61 kPa)
Propane Min 8.0” W.C. (1.99 kPa) – Max. 14.0” W.C. (3.48 kPa)
• Inlet gas pressures that fall outside the range of values listed above may adversely affect the
performance of the water heater. These pressures are measured when the water heater is in full
operation.
• Inlet gas pressure must not exceed the above maximum values; gas pressure above the specified range
will cause dangerous operating conditions and damage to the unit.
• Until testing of the main gas line supply pressure is completed, ensure the gas line to the water heater
is disconnected to avoid any damage to the water heater.
• If the gas supply pressure to the heater is greater than the specified maximum, a field-supplied
regulator is required. The regulator must lower the gas pressure within the approved range.
• Install the gas regulator according to the manufacturer's instructions.
• The regulator must be sized for the water heater input and provide the specified pressures that are
listed on the rating plate.
• In the absence of minimum install distance stated by the regulator manufacturer, it is recommended
that there is at least 3 ft (1 m) of piping between the regulator outlet and the water heater's inlet gas
connection.
-Gas connecons-
1. Install a manual gas shutoff valve between the water heater and the gas supply line.
2. When the gas connections are completed, it is necessary to perform a gas leak test either by applying
soapy water to all gas fittings and observing for bubbles or by using a gas leak detection device.
• The water heater and its individual shutoff valve must be disconnected from the gas supply
piping system during any pressure testing of that system at test pressures in excess of 1/2 psi
(3.5 kPa).
• The water heater must be isolated from the gas supply piping system by closing its individual
manual shutoff valve during any pressure testing of the gas supply piping system at test
pressures equal to or less than 1/2 psi (3.5 kPa).
3. Always purge the gas line of any debris and/or water before connecting to the gas inlet.
Size the gas pipe appropriately to supply the necessary volume of gas required for
the water heater using ANSI Z223.1/NFPA 54 in the USA or B149.1 in Canada or
local codes. Otherwise, flow capabilities and output temperatures will be limited.
NOTICE
Installaon
Installaon Manual
32 Page
-Natural gas supply piping-
Maximum delivery Capacity in Cubic Feet of Gas per Hour (based on IPS Pipe carrying Natural Gas with 0.60 Specific
Gravity with a Pressure Drop of 0.5" W.C.).
Based on Energy Content of 1,000 BTU/Cubic ft: The water heater requires 199 Cubic ft/hr for the 540P model.
The following tables are from NFPA 54.
-Propane (LP) supply piping-
Maximum Capacity of Propane (LP) Based on 11" W.C. supply pressure at a 0.5" W.C. pressure drop
Installaon
Installaon Manual
Water
heater
199,000 BTU/h
Dryer
35,000 BTU/h
Gas meter
Furnace
120,000 BTU/h
Range
65,000 BTU/h
A
B
C
10' (3 m)Length
1/2" Pipe size
15' (4.6 m)Length
1/2" Pipe size
15' (4.6 m)Length
1" Pipe size
10'(3 m)Length
3/4" Pipe size
10' (3 m )Length
1" Pipe size
5' (1.5 m) Length
1-1/4" Pipe size
10' (3 m)Length
3/4" Pipe size
5' (1.5 m)Length
1-1/4" Pipe size
Gas sizing example
(Natural Gas)
Based on Energy Content of 1,000 BTU/Cubic ft:
Divide each appliance's BTU/h requirement by 1,000 BTU/ft
3
to get the appliance's ft
3
/h requirement.
Take into account the distance the appliance is from the gas meter, look in the above gas chart to properly size the line.
For sections of the gas line supplying gas to more than one appliance (Ex: Point A to Point B), add up the cubic ft per hour
requirements of the appliances that are being supplied by that section, and size to the farthest appliance.
For Example: The section from A to B supplies gas to the furnace, range and dryer. Adding up the BTU/h requirements and
dividing by 1,000 yields a cubic ft per hour requirement of 220 cubic ft of gas per hour. The farthest appliance is the range, which
is 50 ft away from the meter. Looking at the above chart, and under the column of 50 ft, Section A to B needs to be 1" in order
to supply 220 cubic ft.
Unit: Cubic feet per hour
Pipe Size
Length
Diameter
10'
(3 .0 m)
20'
(6.1 m)
30'
(9.1 m)
40'
(12.2 m)
50'
(15.2 m)
60'
(18.3 m)
70'
(21.3 m)
80'
(24.4 m)
90'
(27.4 m)
100'
(30.5 m)
125'
(38.1 m)
150'
(45.7 m)
200'
(61.0 m)
1/2"
172 118 95 81 72 65 60 56 52 50 44 40 34
3/4"
360 247 199 170 151 137 126 117 110 104 92 83 71
1"
678 466 374 320 284 257 237 220 207 195 173 157 134
1-1/4"
1,390 957 768 657 583 528 486 452 424 400 355 322 275
1-1/2"
2,090 1,430 1,150 985 873 791 728 677 635 600 532 482 412
2"
4,020 2,760 2,220 1,900 1,680 1,520 1,400 1,300 1,220 1,160 1,020 928 794
Unit: kBTU per hour
Pipe Size
Length
Diameter
10'
(3 .0 m)
20'
(6.1 m)
30'
(9.1 m)
40'
(12.2 m)
50'
(15.2 m)
60'
(18.3 m)
70'
(21.3 m)
80'
(24.4 m)
90'
(27.4 m)
100'
(30.5 m)
125'
(38.1 m)
150'
(45.7 m)
200'
(61.0 m)
1/2"
268 184 148 126 112 101 93 87 82 77 68 62 53
3/4"
567 393 315 267 237 217 196 185 173 162 146 132 112
1"
1,071 732 590 504 448 409 378 346 322 307 275 252 213
1-1/4"
2,205 1,496 1,212 1,039 913 834 771 724 677 630 567 511 440
1-1/2"
3,307 2,299 1,858 1,559 1,417 1,275 1,181 1,086 1,023 976 866 787 675
2"
6,221 4,331 3,465 2,992 2,646 2,394 2,205 2,047 1,921 1,811 1,606 1,496 1,260
33 Page
WATER CONNECTIONS
Do not use this appliance if any part has been under water. Immediately contact a quali-
fied installer or service agency to replace a flooded water heater. Do not attempt to
repair the unit! It must be replaced!
WARNING
Do not reverse the hot outlet and cold inlet connections to the water heater. If you
reverse the connections, the water heater will not activate properly.
NOTICE
All pipes, pipe fittings, valves and other components, including soldering materials, must be suitable for
potable water systems. Also, an automatic air vent or air separator must be installed. This equipment must
be installed according to its manufacturer's instructions.
Installaon
Installaon Manual
1. A manual shutoff valve must be installed on the cold water inlet to the
water heater between the main water supply line and the water heater.
2. In addition, a manual shutoff valve is also recommend-
ed on the hot water outlet and return inlet of the unit.
A thermal expansion tank or code approved device to
handle thermal expansion must be installed.
4. There is a wire mesh filter within the cold inlet and return inlet to trap debris from entering your
heater. This will need to be cleaned periodically to maintain optimum flow. (Refer to p. 63.)
3. Before installing the water heater, flush the water line to remove
all debris, and after installation is complete, purge the air from
the line. Failure to do so may cause damage to the heater.
Cold
inlet
Hot
outlet
Gas inlet
As Close as
Possible
Pressure
relief
valve
Return
inlet
-Installaon with dedicated return line-
Model 540P Indoor 540P Outdoor
Maximum Pipe length*
(Hot Water supply line and
Dedicated Return line)
Pipe
Diameter
3/4"
500 ft (152.4 m)
1/2"
200 ft (61.0 m)
*These are equivalent length that includes head loss for elbows, tees, unions, etc. An additional pump may be
necessary for circulation systems with longer equivalent pipe lengths.
Air vent
Hot water outlet to xtures
Air
separator
S
Check valve
Check valve
Y-Strainer
Cold water inlet
Expansion tank
Gas supply
Ball valves
Unions
Hot water outlet
Cold water inlet
Gas inlet
Pressure
relief valve
This is a concept drawing only.
Return inlet
• Check valves must be installed on both of the cold water line and return line.
Please refer to the above diagram.
• Insulate the hot water supply line and dedicated return line to prevent heat loss.
NOTICE
34 Page
Hot
water
outlet
Gas inlet
Return
inlet
"Cold water inlet"
must be capped.
Cold water supply line must be connected to
the "Return inlet".
-Installaon without recirculaon-
• PUMP TIMER 1 and PUMP TIMER 2 must be set to OFF if you use this installation
method.
• Cold water supply line must be connected to the "Return inlet".
• The "Cold water inlet" must be capped.
NOTICE
Installaon
Installaon Manual
-Pressure relief valve-
The water heater has a high-temperature shutoff switch built in as a standard safety feature (called a
Hi-Limit switch) therefore a “pressure only” relief valve is required.
• This unit does not come with an approved pressure relief valve.
• An approved pressure relief valve must be installed on the hot water outlet.
• The pressure relief valve must conform to ANSI Z21.22 or CAN 1-4.4 and installation must follow local
codes.
• The discharge capacity must be at least 199,000 BTU/h for the 540P model.
• The pressure relief valve needs to be rated for a maximum of 150 psi (1 MPa).
• The discharge piping for the pressure relief valve must be directed so that the hot water cannot splash
outward and cause damage or personal injury.
• Attach the discharge tube to the pressure relief valve and run the end of the tube to within 6 in
(152 mm) from the floor. This discharge tube must allow free and complete drainage without any
restrictions.
• If the pressure relief valve discharges periodically, this may be due to thermal expansion in a closed
water supply system. Contact the water supplier or a local plumbing professional on how to correct
this situation. Do not plug the pressure relief valve.
• The pressure relief valve must be manually operated periodically to check for correct operation.
Before operating the valve manually, check that it will discharge in a place for secure disposal.
• No valve must be placed between the relief valve and the water heater.
WARNING
Hot water could be released. Before operating the pressure relief valve manu-
ally, check that it will discharge in a safe place. If water does not flow freely
from the end of the discharge pipe, turn the gas supply and power OFF and call
a qualified person to determine the cause.
Refer to the pressure relief valve manufacturer's instructions for inspection and
maintenance requirements.
Use this method when recirculation is not used (such as
when the return line will be installed later). Before the
water heater is put into service, ensure that no timers are
set to activate the pump. See "Pump Operation Timers."
Once the return line is installed, follow the instructions in
the previous section, "Installation with dedicated return
line." Complete those instructions BEFORE you set PUMP
TIMER 1 and PUMP TIMER 2 to operate.
• Install the water supply line to the "Return inlet" water
connection.
• Install a 3/4" end cap to the "Cold water inlet" connec-
tion.
35 Page
• Discharge condensate (acidic water) in accordance with all local codes and
common safety practices.
• Use corrosion resistant pipe, such as PVC, for the condensate drain line.
Do not use metal pipe.
• The condensate drain does not require a trap.
• Maintain a downward slope on the drain line(s), including installations in
which the drain is not directly below the water heater.
• A field-supplied bypass is required if a neutralizer is installed.
• Do not connect the condensate drain line directly to a condensate pump.
• If the drain line is required to have bends, ensure that there are no kinks that
will restrict the flow of condensation.
NOTICE
Installaon
Installaon Manual
The water heater is a high efficiency condensing water heater that produces condensate (acidic water).
The acidic condensate generated in the secondary heat exchanger can be neutralized by the neutralizer
accessory (100112159/TH-NT01).
Although a neutralizer is not required, a condensate drain must be installed as described on the next page.
-Condensate drain connecons-
CONDENSATE DRAIN
• The water heater does not include a built-in condensate neutralizer cartridge for reducing the pH level
of condensate water. If local codes dictate that condensate must be neutralized prior to drainage, a
condensate neutralizer must be installed. An accessory Neutralizer assembly (100112159/TH-NT01)
is sold separately. (Refer to p. 10.)
• In the absence of applicable local codes and regulations, the manufacturer recommends that
condensate be disposed of into a drain Connect a drain tube from the condensate drain port (shown
below) located on the bottom of the water heater to a standard drain.
Follow all code requirements
of the local authority on
condensate neutralizers and
whether or not they are required
for the installation.
Condensate drain port
NOTICE
36 Page
Installaon
Installaon Manual
*Maintain downward slope, including installations in which the drain is not directly below the heater.
**A 2" (50 mm) minimum distance must be maintained between the condensate line and drain to allow
full flow of the condensation.
• The condensate drain is at atmospheric pressure (non-pressurized) and therefore must
be allowed to drain freely with gravity only. Ensure that the condensate drain tube is
not plugged or blocked, and ensure that it slopes downward to allow condensate to
flow freely. All portions of the condensate drain (neutralizer and drain tube) must
be at a lower elevation than the water heater to prevent condensate water from
building up inside the heat exchanger.
• Condensate cannot be effectively neutralized if the neutralizer elements inside the
Neutralizer accessory have been completely consumed. If this happens, condensate
will remain acidic and can possibly cause damage to items such as pipes, concrete,
etc., if drained improperly.
• The actual life of the neutralizer may vary, depending on the application and usage.
Replace the cartridge when the condensate pH goes below 6.0.
• Please ensure that the cartridge is properly replaced before the neutralizer elements
have been completely consumed.
• All preventative measures and safety practices must be adhered to when draining condensate.
The manufacturer will not be responsible for any damage caused by condensate.
• A drain pan, or other means of protection against water damage, is recommended to
be installed under the water heater in case of leaks.
NOTICE
1/2"
Condensate
drain tube*
Overflow bypass*
(1/2" Condensate
drain tube)
1/2" MPT
Condensate connection
Neutralizer cartridge (Included
with Neutralizer accessory)
1/2" MPT x 3/8" FPT (Included
with Neutralizer accessory)
1/2" Condensate drain tube*
1/2" Condensate drain tube*
1/2" FPT x 1/2" HB (Included
with Neutralizer accessory)
1/2"
Condensate
drain tube*
1/2" MPT
Condensate
connection
Floor drain, standpipe, pump,
or other acceptable drain
2" (50 mm)
MIN. distance**
Floor drain, standpipe, pump,
or other acceptable drain
Installation
with neutralizer
Installation
without neutralizer
2" (50 mm)
MIN. distance**
2" (50 mm)
MIN. distance**
37 Page
ELECTRICAL CONNECTIONS
• Follow the electrical code requirements of the local authority having jurisdiction.
In the absence of such requirements, follow the current edition of the National
Electrical Code ANSI/NFPA 70 in the U.S. or the current edition of CSA C22.1
Canadian Electrical Code Part 1 in Canada.
• When servicing or replacing parts within the water heater, label all wires prior to
disconnection to facilitate an easy and error-free reconnection. Wiring errors can
cause improper and dangerous operation. Verify proper operation after servicing.
• Failure to observe these warnings could result in personal injury or death.
WARNING
Indoor model comes with a power plug instead of a junction box. The following procedure is for
outdoor model only.
1. The water heater must be electrically grounded. Do not attach the ground wire to either the gas or
the water piping.
2. The water heater requires a 120 VAC, 60 Hz electrical power supply that is properly grounded.
• A proper disconnect (i.e. on/off switch, power plug, etc.) controlling the main power to the water
heater must be provided for service reasons. (Must comply with local codes.)
• Connect the power supply to the water heater exactly as shown in the wiring diagram.
3. A green screw is provided in the junction box to ground the connection.
4. The water heater can be hardwired or wired to a plug-in.
5. The use of a surge protector is recommended in order to protect the unit from power surges.
Outdoor model
Boom view of water heater
View of electrical
connecons of water heater
Indoor model
Connect
Power supply
120VAC, 60Hz
Ground
Green screw
Installaon
Installaon Manual
38 Page
TEMPERATURE REMOTE CONTROLLER
-Included accessories - Outdoor model only
Installaon
Installaon Manual
Fig. B
<Mounting and Wiring the Remote Controller>
1. Take the Frame off of the remote controller with a flat head screwdriver. (Fig. A and B)
2. Attach the Metal plate on the wall with two provided screws. (Fig. B)
3. If you use another cable, crimp the Fork terminals to the wires. (Fig. C)
Cut out (removed during later steps).
Frame
Main unit
Metal plateAached short screws
A + B
3-1/4 inch
(83.5 mm)
Hook B to the Fixing
bracket on A.
A
B
Fig. A
Press and twist flat
head screwdriver
against the cutout.
Twist
Remote controller cable
1-3/8 Inch
(35 mm)
Fig. C
1-5/8 Inch
(41 mm)
Fork
Terminals
100276687 (TM-RE43)
It is also an optional accessory as a second remote for the indoor model. Refer to pp. 9 and 10.
*The optional remote controller (100276687/TM-RE43) has no remote controller cable.
Verify that the items listed below are included with the remote controller.
Temperature
remote controller
Screws Fork terminals Manual
Remote controller
cable*
Qty: 1
Qty: 2
Qty: 4
Qty: 1
Qty: 1
• The remote control is an optional accessory that can be installed in a hall, closet, etc., to allow for
temperature adjustment without having to go to the heater.
• When installed, the remote will take priority over the built-in controller of indoor models.
-Installaon-
• This remote controller is NOT waterproof.
• The water heater can only have one remote controller.
• Do not install in high temperature environments, high humidity conditions outdoors, in
direct sunlight, or within the reach of children.
• Make sure the remote controller does not come into contact with water or oil.
• Failure to observe these warnings could result in personal injury or electrical shock.
WARNING
• Do not place the remote controller cable close to other wires from other products.
• Cables used for the remote controller connection must be:
• Minimum 20 gauge wire (No polarity)
• Maximum 400 ft (122 m) long
NOTICE
39 Page
<How to connect the remote controller to the water heater>
1. Disconnect power supply from the water heater.
2. Take off the water heater’s front cover.
3. Locate the remote controller terminals. See the diagrams below.
4. Take off the back plate from the remote controller, and then attach the two fork terminals to con-
nector base on the backside of the remote controller with two screws. Make sure the terminals are
firmly fixed. (See the above instructions for installation of the remote controller.)
5. Pull the remote controller cable through the hole at the bottom of the water heater’s casing.
6. Properly attach the remote controller cable to the remote controller terminal on the computer board
(No polarity). * Do NOT jump or short-circuit the cable, or the computer will be damaged.
7. Replace the front cover securely.
Inlet for the remote
controller cable
Cut out
Fig. D-2
Fig. D-1
Installaon
Installaon Manual
Connect other end to these terminals
Plasc
cover
Back side of the remote
Remote controller terminals
Remote controller cable
Two fork terminals
4. Open the Plastic cover and tighten the two Fork terminals beneath the two Remote controller
terminal screws on the back of the Main unit (Fig. D-1). Cut out the inlet for the cable from the
bottom of the main unit (Fig. D-2). Insert the cable through the inlet.
5. Close the Plastic cover and then hook the Main unit to the Fixing bracket on the Metal plate. (Fig. B)
6. Attach the Frame back onto the remote.
540P model
100276687
(TM-RE43)
40 Page
EASY-LINK SYSTEM
The 540P model water heater can be connected to 540/CT-199 models as only a PARENT unit in
an Easy-Link System.
• The built-in Easy-Link System allows up to 4 units to manifold together.
• Only one 540P can be installed in an Easy-Link System.
• A communication cable (gray color) comes with each 540/CT-199 model.
You can manifold from 2 to 4 units. A 4-unit system has full automatic modulation between
13,000 BTU/h (Propane) or 15,000 BTU/h (Natural gas)to 796,000 BTU/h.
Type of unit Model
Allocated No.
from controller
PARENT 540P 1
CHILD-1/2/3
540
CT-199
2,3,4*
*Each CHILD unit is allocated the above num-
ber from controller, which indicates on the
display of the controller on the unit. (Refer
to p. 65.)
Hot Out
Gas In
Cold In
Return
Line
• The Easy-Link System is limited to up to 4 units. If you connect more than 4 units, only
the first 4 units will work as a part of the Easy-Link System. The other additional units
will not work.
• In the Easy-Link System, one unit must be designated as a PARENT unit by
changing one of its DIP switch settings. The other units are CHILD units. The
540P model must be a PARENT unit and cannot be a CHILD unit. (The 540/
CT-199 model can be either a PARENT unit or a CHILD unit.)
• A 540P model only can be connected to 540/CT-199 models when 540P is a PARENT
unit in the system.
• A remote controller is not required for an Easy-Link System. However, it does provide
for more temperature options and ease of maintenance.
• If a remote controller is used, the temperature on all the units in the system will auto-
matically be set to the same temperature that is set on the remote.
• When a remote is used in an Easy-Link System, it must be connected to the parent unit.
• Only one remote can be connected.
NOTICE
-Easy-Link connecon procedures for 540P & 540/CT-199 models-
1. Make sure the power to the heaters are off.
2. Verify the DIP switch set temperatures of all units within the system. Every single water heater
must be set to the same set temperature. If a remote controller is used, it should be installed to the
“PARENT” unit. The remote will set the temperature for the entire system. When the 540P model is
the “PARENT” unit, the only controller that can be used is the 100276687 (TM-RE43).
3. Select 540P unit to be the “PARENT” unit. The “PARENT” unit should be one of the end units.
4. “PARENT” unit:
On the 540P that you select to be the “PARENT” unit, locate the three banks of DIP switches at the
upper left of the computer board. Change DIP switch No. 1 on the middle bank of DIP switches to
the ON position. See the computer board diagram as shown on the next page. Do not change any DIP
switches on any of the “CHILD” units.
Installaon
Installaon Manual
41 Page
Installaon
Installaon Manual
(B) Basic diagram of connections between the Easy-Link System units
PARENT
Communicaon cable
Connectors
Middle bank of
DIP switches
OFF
ON
1
1
12
2
2
PARENT
PARENT
PARENT
1
2
3
4
5
6
Connectors Connectors Connectors
OFF
ON
1
2
3
4
5
6
OFF
ON
1
2
3
4
5
6
Lower bank of
DIP switches
Lower bank of
DIP switches
Lower bank of
DIP switches
1
2
3
4
5
6
OFF
ON
PARENT UNIT
540P
CHILD UNIT
540/CT-199
CHILD UNIT
540/CT-199
CHILD UNIT
540/CT-199
Built-in
or
remote
controller
Easy-Link
connector is
idened by
a label.
Middle bank of DIP switches
Upper bank of DIP switches
Lower bank of DIP switches
(A) 540P model computer board
WARNING
• To change the DIP switch settings for the Easy-Link System, locate the
MIDDLE bank of DIP switches at the upper left of the 540P computer
board. (See diagrams below.)
• DO NOT adjust any other DIP switches .
• Turn off the power supply to the water heater before changing the DIP
switch settings.
• Failure to observe this warning could result in carbon monoxide poisoning
or death.
5. Between the “PARENT” and the “CHILD-1” units:
Connect the “PARENT” connector of the “PARENT” unit to the “1” connector of the “CHILD-1” unit
using the supplied linking cable.
6. Between the “CHILD-1” and the “CHILD-2” units:
Connect the “2” connector of the “CHILD-1” unit to the “1” connector of the “CHILD-2” unit.
7. Between the “CHILD-2” and the “CHILD-3” units:
Connect the “2” connector of the “CHILD-2” unit to the “1” connector of the “CHILD-3” unit.
8. Verify that all cables are connected like the diagram on the next page (B).
9. Turn on power to the “PARENT” unit.
Turn on “CHILD-1”. When the (remote and/or built-in) controller displays a number, turn on “CHILD-2”.
When the (remote and/or temperature) controller displays a number, turn on “CHILD-3”.
Make sure the (remote and/or temperature) controller display the unit #. The numbering system
automatically allocates the unit # to each water heater in the Easy-Link System, in accordance with the
table above.
• The dark squares indicate the correct position of the DIP switch.
• Either a built-in controller or a remote controller is required for the Easy-Link System
for ease of usage and maintenance.
NOTICE
42 Page
APPLICATIONS
-Combination potable water heating and space heating-
-Recirculaon-
*The integrated recirculation pump is controlled by a programmed timer and ON/OFF temperatures are detected
by thermistors in the water heater. Refer to pp. 52 to 57 to set the timer and ON/OFF temperatures.
*Make sure flow rate of recirculation is not less than 2 GPM (7.5L/min) and no more than 4 GPM (15L/min)
through the system. Refer to p. 58 for "Manual pump activation" and p. 60 for how to check the flow rate.
Applicaons
Installaon Manual
• This water heater is suitable for combination water (potable) heating and
space heating and not suitable for space heating applications only.
• In order to purge air in water pipes within a closed-loop system, an air vent
and air separator should be installed in the system. Required circulation
flow rates are labeled next to each application diagram. These flow rate
requirements must be followed.
• Toxic chemicals used in boiler treatments such as alcohol, glycerol and glycol
groups must not be introduced into the system
• The water heater can be used to supply potable water and space heating and
shall not be connected to any heating system or component(s) previously
used with non-potable water where any chemicals were added to the water
heating appliances.
• When the system requires water for space heating at temperatures higher
than required for other uses, a means such as a mixing valve shall be installed
to temper the water for those other uses in order to reduce scald hazard
potential.
• Water temperature over 125 °F (52 °C) can cause severe burns instantly or
death from scalding.
• Failure to observe these warnings could result in severe personal injury or
death.
WARNING
Air vent
Hot water outlet to xtures
Air
separator
S
Check valve
Check valve
Y-Strainer
Cold water inlet
Expansion tank
Gas supply
Ball valves
Unions
Hot water outlet
Cold water inlet
Gas inlet
Pressure
relief valve
This is a concept drawing only.
Return inlet
43 Page
• Priority Control Devices such as a flow switch, an Aquastat or other electronic
controller can be used to prioritize the domestic water system over the heating
system.
• Follow all local codes, or in the absence of local codes, follow the current edition
of the National Standard Code, ANSI Z21.10.3 • CSA 4.3.
• This illustration is a concept design only. The reference to the 1/8
th
hole in check
is only for the State of Massachusetts. There are a wide variety of variations to
the application of controls and equipment presented. Designers must add all
necessary safety and auxiliary equipment to conform to code requirements and
design practice. For more details, contact the manufacturer.
• The built-in pump may not provide sufficient flow for the heating coil. An
additional field-supplied pump may be necessary.
NOTICE
-Dual-purpose hot water heang-
(Domestic and Space Heating):
Diagrammatic layout of radiant heating and domestic water heater.
The recirculation pump is to provide no less than 2 GPM (7.5 L/min) and no more than 4 GPM (15 L/min)
through each activated unit in the system
120 VAC
switch or
outlet
Hot water outlet
Unions
T-handle gas shuto valve
Check valve
Electronically controlled
pump mer. Acvates
every 6 hours for 60
seconds. Wire to
product approved pump
Heang Coil
(used with air-handler)
Cold water supply
3-inch gas exhaust
vent (Discharge must
comply with local and
state codes.) Cannot
be common vented
with other appliances
in Massachuses.
An approved temperature and pressure
relief valve. Tie to locaon approved by
local codes and must meet BTU rang of
water heater model used
Check valve will have
1/8-inch hole drilling
in clapper oponal
Atmospheric
vacuum
breaker
Shuto
valve
Pressure
gauge
Apply correct thermal
expansion tank-size
per applicaon
Shuto valves
Shuto valves
Check valves
Cold water inlet
Gas inlet
Water
lter
Drain
plug
Thermostac mixing valve
Hot water
supply and
return to
heang coil
System installed with reverse
acng aquastat to shut o fan.
Suggested but not required by
248 CMR
50’-0” maximum distance from
water heater to fan coil.
(Developed length) Not including
coil in heang unit
NSF-61 product
approved pump
Automac tempering device
must be installed below
the top of the water heater
as per manufacturer’s
recommendaons
Piping loop
between water
heater and fan
coil shall be in
compliance with
248 CMR
Tempered water to
plumbing xtures. Must
meet temperature
requirements of 248 CMR
All water piping should be insulated
in accordance with 780 CMR
(Massachuses energy code)
Installaon Manual
Ball
Valve
Isolation
Valve
Applicaons
44 Page
INITIAL OPERATION
Inial operaon
Installaon Manual
IF YOU SMELL GAS:
• Do not try to start the water heater.
• Do not touch any electric switches; 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.
• Failure to observe these warnings could lead to fire or an explosion, resulting in
severe injury or death.
WARNING
• Check the GAS and WATER CONNECTIONS for leaks before firing unit for the first time.
• Open the main gas supply valve to the unit using only your hand to avoid any spark. Never use
tools. If the knob will not turn by hand, do not try to force it; call a qualified service technician.
Forced repair may result in a fire or explosion due to gas leaks.
• Be sure to check for the presence of leaking gas toward the bottom of the unit because some
gases are heavier than air and may settle towards the floor.
• Check the GAS PRESSURE. Refer to p. 31.
• Do not try to light the burner manually. It is equipped with an electronic ignition device which
automatically lights the burner.
• Check for PROPER VENTING and COMBUSTIBLE AIR to the water heater.
• Purge the GAS and WATER LINES to remove any air pockets.
• 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 unit!
It must be replaced!
FOR YOUR SAFETY, READ BEFORE OPERATING
Initial Test Run
1.
Turn on the 120 VAC, 60 Hz power supply to the water heater.
2.
Open the valve on the inlet water and wait for all pipes to fill
with water.
3.
Clean filter of any debris. Refer to p. 63 for instructions.
4.
Open a hot water tap to verify that water is flowing to that tap,
then close the hot water tap.
5.
Open the manual gas valve.
45 Page
Initial Test Run
6.
Start pump operation test by built-in controller or remote con-
troller.
Press the ON/OFF button on the controller so the STAND BY LED
turns off.
or
Press and hold "INFO." and "PUMP" simultaneously for at least
three seconds, then the integrated pump starts operation for
five minutes.
or
A segment of the zero is lighting as follows in clockwise order
during pump operation test.
7.
During the pump operation test, open and close a faucet in the loop
several times to relieve air in the pipe. If air is stuck in the pump, it
can cause pump failure or decreased water flow.
8.
Check recirculation water flow. Refer to p. 60. Make sure the flow
rate is approx. 2 to 3 GPM. If the flow rate is less than 2 GPM, there is
a possibility that air is stuck in the pump. Open and close the faucet
again to relieve air.
Water flow
(EX.: 3.0 GPM)
9.
After finishing the pump operation test, complete the following
procedures (Refer to pp. 51 to 55.):
• OUTLET WATER TEMPERATURE SETTING
• SETTING THE TIME
• SETTING PUMP TIMERS
• SELECTING A PUMP TIMER
10.
Now you are ready to enjoy hours of endless hot water.
Inial operaon
Installaon Manual
46 Page
This page is intentionally left blank.
Inial operaon
Installaon Manual
47 Page
Owner's Guide
Operang Safety
Owner's Guide
CONGRATULATIONS
Congratulations and thank you for choosing our tankless water heater.
Before use, we recommend that you read
through this owner's guide
carefully. Keep this manual for future reference.
If you need an additional manual, contact the manufacturer or your
local distributor. You may also download a manual from our website.
When you call, please tell us the product name and the serial number
of your unit written on the rating plate of the water heater.
48 Page
Operang Safety
Owner's Guide
OPERATING SAFETY
WARNING:
If you do not follow these instructions exactly, a re or explosion may result
causing property damage, personal injury or loss of life.
A. 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.
B. BEFORE OPERATING smell all around the appliance area for gas. Be sure to smell next to
the oor because some gas is heavier than air and will settle on the oor.
WHAT TO DO IF YOU SMELL GAS
• Do not try to light any appliance.
• Do not touch any electric 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 re department.
C. Use only your hand to turn the gas shutoff valve. Never use tools. If the valve will not turn by
hand, don’t try to repair it, call a qualied service technician. Force or attempted repair may result
in a re or explosion.
D. Do not use this appliance if any part has been under water. Immediately contact a qualied
installer or service agency to replace a ooded water heater. Do not attempt to repair the unit! It
must be replaced!
1. STOP! Read the safety information above on this label.
2. Turn off all electric power to the appliance.
3. Do not attempt to light the burner by hand.
4. Turn the gas shutoff valve located on the outside of the unit to the closed position.
5. Wait ve (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 the gas shutoff valve located on the outside of the unit to the open position.
7. Turn on all electrical power to the appliance.
8. If the appliance will not operate, follow the instructions in “To Turn Off Gas to Appliance,” and
call your service technician or gas supplier.
1. Turn off all electric power to the appliance if service is to be performed.
2. Turn the gas shutoff valve located on the outside of the unit to the closed position.
FOR YOUR SAFETY READ BEFORE OPERATING
OPERATING INSTRUCTIONS
TO TURN OFF GAS TO APPLIANCE
49 Page
Operang Safety
Owner's Guide
A pressure relief valve listed as complying with the standard for Relief Valve and Automatic Gas Shutoff
Devices for Hot Water Supply System, ANSI Z21.22
・
CSA 4.4, shall be installed at the time of installation
of the water heater in the location specied by the manufacturer. Local codes shall govern the installation of
relief devices for safety operation of the water heater. The relief valve must not be removed or plugged.
No valve shall be placed between the relief valve and the water heater. The relief from the discharge of
the pressure relief valve shall be disposed of in a suitable place where it will cause no damage. Also, there
shall be no other reducing coupling or other restrictions installed on the discharge line to restrict ow.
See Installation Manual heading “PRESSURE RELIEF VALVES” for installation and maintenance of relief
valve discharge line and other safety precautions.
Vapors from ammable liquids will explode and catch re causing death or severe burns.
Do not use or store ammable products such as gasoline, solvents or adhesives in the same room or
area near the water heater.
Keep ammable products:
1. Far away from heater.
2. In approved containers.
3. Tightly closed and out of reach of children.
4. Water heater has a main burner, which may
come on at any time and will ignite ammable
vapors.
Vapors:
1. Cannot be seen.
2. Are heavier than air.
3. Go a long way on the oor.
4. Can be carried from other rooms to the main
burner by air currents.
Do not install water heater where ammable products will be stored or
used unless the main burner is at least 18” above the oor. This
will reduce, but not eliminate the risk of vapors being ignited by the
main burner.
Read and follow water heater warnings and instructions. If the owner’s
manual is missing, contact the retailer or manufacturer.
Flammable Vapors
FLAMMABLES
1. Water temperature over 125°F (52°C) can cause severe burns instantly or death from
scalds.
2. Children, disabled and elderly are at highest risk of being scalded.
3. Feel water before bathing or showering.
4. Temperature limiting valves are available. See manual.
5. The outlet temperature of the water heater is set at 120°F (50°C). If you require water temperatures
below this setting, follow the instruction manual.
6. Use this heater at your own risk. Test the water before bathing or showering. Do not leave children or
an inrm person unsupervised. See your local water supply company [plumbing hardware retailer] for
temperature limiting valves that are available.
BRÛLURE
BURN
CHAUDECHAUDE
HOTHOT
CHAUDE
HOT
DANGER
DANGER
50 Page
Normal Operaon
Owner's Guide
NORMAL OPERATION
BUILT-IN CONTROLLER and REMOTE CONTROLLER
The illustraon below shows an example of the controllers. The exact display may dier from examples.
1. Open a cold water
fixture.
2. Mix hot water with the cold water
to get the correct temperature water.
3. When finished, close the
water fixtures.
• Flow rate to activate the water heater: 0.5 gallon per minute at the default set
temperature (1.9 L/min.)
• Flow rate to keep the water heater running: 0.4 gallon per minute (1.5 L/min.)
NOTICE
GENERAL
Built-in controller Remote controller
6 75
1
8
2
3
4
9
6 85
2
3
9
174
No. Description Note No. Description Note
1
"ON/OFF"
Button
Press this button to start or stop
operation.
5
"TIME"
Button
Press this button to set the
current time.
2
"HOT"
Button
Press the "HOT" button or the
"COLD" button to set the outlet
water temperature, the current
time, and PUMP TIMER.
6
LCD
The current time, set temperature,
error code and other information
are displayed.
3
"COLD"
Button
7
"PUMP"
Button
Press this button to set and con-
trol the pump operation.
4
"INFO."
Button
Press the "INFO." button to dis-
play the inlet & outlet water tem-
perature and water flow and set
the outlet temperature, pump
choosing, and unit conversion.
8
IN USE LED
The LED lights during combustion.
9
STAND BY LED
The LED lights when power is on.
Temperatures above 125 °F (52 °C) can cause severe burns or death from scalding.
Children, disabled and the elderly are at high risk of being injured.
WARNING
°F 120 125 130 135 140 145 150 155
°C 49 52 54 57 60 63 66 68
Time to produce
serious burn
more
than 5
min.
1½ to 2
min.
about
30 sec.
about
10 sec.
less than
5 sec.
less than
3 sec.
about
1½ sec.
about
1 sec.
• When the remote controller is installed it will take priority over the built-in controller.
• The controller has an energy saving mode. Five minutes after the water heater stops
operating, the backlight of the controller turns off.
• The backlight of the remote will turn back on once the water heater begins firing again.
NOTICE
51 Page
NOTICE
• The controllers have an energy saving mode. Five minutes after the water
heater stops operating, the backlight of the controllers turns off.
• The backlight of the controllers will turn back on once the water heater begins
firing again.
Normal Operaon
Owner's Guide
Operation
Controllers
Built-in controller Remote controller
1.
Turn on the 120 VAC power supply to the unit.
2.
Press the "ON/OFF" button on the controller in order to
turn the controller on.
3.
When ON, the STAND BY LED is lit.
4.
It shows the set temperature of output water on its
display as shown in the picture on the right. (EX.: 120 °F)
5.
Press the "HOT" button or the "COLD" button to set the
temperature setting of the unit.
Increasing temperature from 120 °F (50 °C) to 125 °F (52 °C) :
1. The water heater must be in Stand By to increase the
temperature.
2. Press the "HOT" button to set 120 °F (50 °C).
3. Press and hold the "INFO" button and the "HOT"
button for at least 3 seconds. The remote will emit a
beep and change to 125 °F (52 °C).
4. Press the "HOT" button to set up to 140 °F (60 °C).
(EX.: 120 °F)
OUTLET WATER TEMPERATURE SETTING
-Set temperature-
TEMPERATURE TABLE OF CONTROLLER
°F 100 105 110 115 120* 125 130 135 140
°C 38 40 43 45 50* 52 55 57 60
*Factory setting (Default): 120 °F (50 °C)
52 Page
Operation
Controllers
Built-in controller Remote controller
1.
Turn on the 120 VAC power supply to the unit.
2.
Press the "TIME" button on the controller in order to set
the time. This operation is available regardless of ON/
OFF of the controller.
The time in the display will flash.
The controllers can only have 24 hours indication of time.
3.
Press the "HOT" button or "COLD" button to set the time.
Press and hold the "HOT" or "COLD" button to adjust the
time more quickly.
NOTICE: The time is displayed in twenty-four hour clock time.
For example, 11:00 is 11:00 a.m. and 23:00 is 11:00 p.m.
4.
Press the "TIME" button on the controller in order to
save and exit.
When the remote is on, the current time and set
temperature are displayed.
When the remote is off, the display turns off.
OR
SETTING THE TIME
PUMP OPERATION TIMERS
The built-in controller and remote offer two timer settings for the pump operation:
PUMP TIMER 1 and TIMER 2.
The pump will only operate during the times set for TIMER 1 and TIMER 2.
There are four options for pump timer operation.
1. Both PUMP TIMER 1 and PUMP TIMER 2 are activated.
2. Neither PUMP TIMER 1 nor PUMP TIMER 2 are activated.
(The recirculation pump will never operate in this mode.)
3. Only PUMP TIMER 1 is activated.
4. Only PUMP TIMER 2 is activated.
NOTICE: Set the time for PUMP TIMER 1 and PUMP TIMER 2 before you select a
pump timer option. Follow the steps in SETTING THE TIME, then complete the
steps in Setting pump timers.
PUMP TIMERS 1 & 2
activated
NO PUMP TIMER
activated
Only PUMP TIMER 1
activated
Only PUMP TIMER 2
activated
Normal Operaon
Owner's Guide
53 Page
- Seng pump mers -
Operation
Controllers
Built-in controller Remote controller
1.
Turn on the 120 VAC power supply to the unit.
2.
Press and hold the "PUMP" button on the controller for
at least 3 seconds to enter the pump timer setting mode.
This operation is available regardless of ON/OFF of the
controller.
The ON time for PUMP TIMER 1 will flash, indicating that
you can set the start time.
3.
Press the "HOT" button or "COLD" button to select the
time. Press and hold the "HOT" or "COLD" button to
adjust the time more quickly.
NOTICE: The time is displayed in twenty-four hour clock time.
For example, 11:00 is 11:00 a.m. and 23:00 is 11:00 p.m.
4.
Press the "PUMP" button when the desired time flashes
on the display.
The OFF time for PUMP TIMER 1 will flash, indicating that
you can set the end time.
5.
Press the "HOT" button or "COLD" button to select the
time. Press and hold the "HOT" or "COLD" button to
adjust the time more quickly.
NOTICE: The time is displayed in twenty-four hour clock time.
For example, 11:00 is 11:00 a.m. and 23:00 is 11:00 p.m.
6.
Press the "PUMP" button when the desired time flashes
on the display.
The ON time for PUMP TIMER 2 will flash, indicating that
you can set the start time.
Normal Operaon
Owner's Guide
54 Page
Operation
Controllers
Built-in controller Remote controller
7.
Press the "HOT" button or "COLD" button to select the
time. Press and hold the "HOT" or "COLD" button to
adjust the time more quickly.
NOTICE: The time is displayed in twenty-four hour clock time.
For example, 11:00 is 11:00 a.m. and 23:00 is 11:00 p.m.
8.
Press the "PUMP" button when the desired time flashes
on the display.
The OFF time for PUMP TIMER 2 will flash, indicating that
you can set the end time.
9.
Press the "HOT" button or "COLD" button to select the
time. Press and hold the "HOT" or "COLD" button to
adjust the time more quickly.
NOTICE: The time is displayed in twenty-four hour clock time.
For example, 11:00 is 11:00 a.m. and 23:00 is 11:00 p.m.
10.
Press the "PUMP" button when the desired time flashes
on the display.
11.
The following steps will set the temperature drop
that must occur before the recirculation pump will
activate.
Temperature drop below set temp. at which
pump turns on
°F -10 -15 -20* -25 -30 -35 -40
°C -6 -8 -11 -14 -17 -19 -22
*The value has been preset at the factory. (Default)
Press the "HOT" button or the "COLD" button to select
the temperature at which the pump will activate.
12.
Press the "PUMP" button on the controller to save your
settings.
Normal Operaon
Owner's Guide
55 Page
Operation
Controllers
Built-in controller Remote controller
13.
The following steps will set the temperature drop
that must occur before the recirculation pump will
turn off.
Temperature drop below set temp. at which
pump turns off
°F -5* -10 -15 -20 -25 -30 -35
°C -3 -6 -8 -11 -14 -17 -19
*Preset at the factory. (Default)
Press the "HOT" button or the "COLD" button to select
the temperature at which the pump will turn off.
14.
Press the "PUMP" button on the controller to save your
settings.
When the controller is on, the current time and
set tempera
ture in the display turns on.
When the controller is off, the display turns off.
OR
- Selecng a pump mer-
Operation
Controllers
Built-in controller Remote controller
1.
Press the "PUMP" button on the controller to set the
mode. (The options are shown in step 3.) This operation
is available regardless of the ON/OFF status of the
controller.
2.
The current status of the PUMP TIMER will flash for 10
seconds. During this time, you can change the mode.
Otherwise, the mode will remain unchanged.
3.
Press the "PUMP" button on the controller in order to
change the option. The order of the option is as follows.
PUMP TIMERS 1 & 2
activated
NO PUMP TIMER
activated
Only PUMP TIMER 1
activated
Only PUMP TIMER 2
activated
4.
Press the "INFO" button on the controller in order to save
your setting.
Normal Operaon
Owner's Guide
56 Page
Examples
Controllers
Built-in controller Remote controller
1.
The display shows that PUMP TIMER 1 is in operation. The
current time falls within the time range that is set for for PUMP
TIMER 1.
Current time: 8:00 AM (8:00)
Set temperature of output water: 120 °F
PUMP TIMER 1: SET
PUMP TIMER 2: OFF
2.
The display shows that PUMP TIMER 1 is NOT in operation. The
current time falls outside the time range that is set for for PUMP
TIMER 1.
Current time: 10:00 AM (10:00)
Set temperature of output water: 120 °F
PUMP TIMER 1: SET
PUMP TIMER 2: OFF
3.
The display shows that PUMP TIMER 2 is in operation. The
current time falls within the time range that is set for for PUMP
TIMER 2.
Current time: 8:00 PM (20:00)
Set temperature of output water: 120 °F
PUMP TIMER 1: OFF
PUMP TIMER 2: SET
4.
The display shows that PUMP TIMER 2 is NOT in operation. The
current time falls outside the time range that is set for for PUMP
TIMER 2.
Current time: 10:00 PM (22:00)
Set temperature of output water: 120 °F
PUMP TIMER 1: OFF
PUMP TIMER 2: SET
5.
The display shows that PUMP TIMER 1 and PUMP TIMER 2 are
set, and one of them is in operation. In this example, PUMP
TIMER 1 is running because it is set to activate between 6:00 AM
and 9:00 AM. (See above.)Current time: 7:00 AM (7:00)
Set temperature of output water: 120 °F
PUMP TIMER 1: SET
PUMP TIMER 2: SET
6.
The display shows that PUMP TIMER 1 and PUMP TIMER 2 are
set, and none of them is in operation.
The current time falls outside the time ranges that are set for for
PUMP TIMER 1 and PUMP TIMER 2.
Current time: 10:00 AM (10:00)
Set temperature of output water: 120 °F
PUMP TIMER 1: SET
PUMP TIMER 2: SET
-Display example-
Normal Operaon
Owner's Guide
The display on the controller indicates which PUMP TIMER is set by displaying a number below the time:
1, 2, or 12. (12 indicates PUMP TIMER 1 and PUMP TIMER 2.)
The arrow to the right of ON or OFF indicates the current status of the PUMP TIMER(s). If the current
time falls within the time range set for a PUMP TIMER, the arrow will point toward ON. (The timer is ON.)
If the current time falls outside the time range set for a PUMP TIMER, the arrow will point toward OFF.
(The timer is OFF.)
See below for examples of each scenario. In each scenario below, PUMP TIMER 1 is set to activate at
6:00 AM (6:00) and deactivate at 9:00 AM (9:00). PUMP TIMER 2 is set to activate at 6:00 PM (18:00) and
deactivate at 9:00 PM (21:00).
57 Page
-Pump operation test-
Operation
Controllers
Built-in controller Remote controller
1.
Press the ON/OFF button on the controller so the
STAND BY LED turns off.
2.
Press and hold "INFO." and "PUMP" simultaneously
for at least 3 seconds, then the integrated pump
starts operation for 5 minutes.
3.
A segment of the zero (on the right) is lit as follows in clockwise order
during forced pump operation.
4.
The pump will stop operation automatically after five
minutes.
OR
Press the "ON/OFF" button to stop pump operation
test.
Operation
Controllers
Built-in controller Remote controller
1.
Press the "PUMP" button to start pump operation
and fire the water heater.
2.
"P" and the set temperature are indicated (on the
right) during Manual pump operation.
3.
The pump will stop automatically in five minutes and
the current set temperature and time will be
displayed on the screen.
Normal Operaon
Owner's Guide
The following procedure will operate the pump. This is useful to verify that the pump is operating prop-
erly and to check the water flow rate.
-Manual pump operation-
This operation runs the pump and fire the water heater each time the “PUMP” button is pushed to mini-
mize energy consumption. The pump runs until water temperature at the thermistor inside the water
heater reaches 102 °F (38.9 °C) or the water temperature at the thermistor rises 10 °F (5.6 °C) above the
initial temperature of the water. The pump runs for five minutes at the
longest. No. 5 DIP switch of the
lower bank needs to be changed to "ON" position in the operation.
Note: The pump timer is not available when the No. 5 DIP switch of the lower bank is set to "ON".
58 Page
Normal Operaon
Owner's Guide
WARNING
• For manual pump operation, adjust only the No. 5 DIP switch in the
LOWER bank of DIP switches. (See below.) DO NOT adjust the other DIP
switches.
• Turn off the power supply to the water heater before changing the DIP
switch settings.
• Failure to observe these warnings could lead to carbon monoxide poi-
soning or death.
Set DIP switch shown in the table below.
Manual pump operation
Lower bank
of
DIP switches
1 2 3 4 5 6 7 8
ON
No. 5 : OFF
DEFAULT
1 2 3 4 5 6 7 8
ON
No. 5 : ON
Lower bank of DIP switches
59 Page
ADDITIONAL FEATURES
-Informaon mode-
You can get some information about the water heater condition by pressing the "INFO" button. For more
information, follow the procedures below:
Normal Operaon
Owner's Guide
Operation
Controllers
Built-in controller Remote controller
1.
Press the "INFO" button on the controller to enter the
information mode.
2.
Press the "INFO" button to display the inlet water
temperature.
Inlet water temperature
(EX.: 60 °F)
3.
Press the "INFO" button again to display the outlet
water temperature.
4.
Press the "INFO" button again to display the water
flow.
5.
Press the "INFO" button to exit the information mode.
Outlet water temperature
(EX.: 120 °F)
Water flow
(EX.: 3.5 GPM)
NOTICE
When installed on an indoor heater, the 100276687 (TM-RE43) has priority for set
temperature over the built-in controller.
-Unit conversion mode-
Units of measure can be changed from Imperial to Metric and vice versa. For example, temperature can
be changed from °F to °C. Flow rate will also change from gallons per minute to liters per minute when
this setting is changed. Follow this procedure to change this setting:
Operation
Screen on the controller
Built-in controller Remote controller
1.
Press the "ON/OFF" button on the controller in order to
turn the controller on.
2.
When ON, the STAND BY LED is lit.
3.
The current set temperature and time will be
displayed on the screen.
4.
Press the "INFO" buttons for at least 3 seconds.
5.
The set temperature should now be displayed in the
alternate unit of measurement.
(EX.: 120 °F)
(EX.: 50 °C)
60 Page
SETTING THE TEMPERATURE ON THE PCB (WITHOUT BUILT-IN
CONTROLLER or REMOTE CONTROLLER)
There are two preset temperatures (120°F (50°C) and 140°F (60°C)) that you can select when the tem-
perature controller is inoperable. To do so, adjust the appropriate DIP switch as shown in the table below.
When the remote controller is in normal operation, the set temperature of the remote controller is given
priority over the set temperature of the DIP switch settings.
Normal Operaon
Owner's Guide
NOTE: Only change the switches with dark squares. The dark squares indicate the correct DIP
switch positions.
The temperature has been preset at the factory to 120 °F (50 °C).
Middle bank of DIP switches
120 °F (50 °C)
DEFAULT
140 °F (60 °C)
1 2 3 4 5 6
ON
No.5 : OFF
1 2 3 4 5 6
ON
No.5 : ON
WARNING
• To set the temperature, adjust only the No. 5 DIP switch in the MIDDLE
bank of DIP switches. (See below.) DO NOT adjust the other DIP switches.
• Turn off the power supply to the water heater before changing the DIP
switch settings.
• Failure to observe these warnings could lead to carbon monoxide poison-
ing, severe personal injury, or death.
FLOW
Appliance/Use
Flow rate
GPM (US) L/min
Lavatory Faucet 1.0 3.8
Bath Tub 4.0 – 10.0 15.2 - 37.8
Shower 2.0 7.5
Kitchen Sink 1.5 5.6
Dishwasher 1.5 5.6
Washing machine 4.0 15.2
Household Flow Rates
Taken from UPC 2006
• The flow rate through the water heater is limited to a maximum of 10.0 GPM (38 L/min) for the
540P model.
• The temperature setting, along with the supply temperature of the water will determine the flow rate
output of the unit.
• Please refer to the temperature vs. gallons per minute chart on p. 76 to determine the likely flow rates
based on your local ground water temperature and your desired outlet water temperature.
• Refer to the table below for typical household plumbing fixture flow rates to determine what the water
heater can do in a household application.
Middle bank
of DIP switches
Lower bank of
DIP switches
Upper bank of
DIP switches
61 Page
WARNING
• To set pump operation for freeze protection, adjust only the No. 4 DIP
switch in the UPPER bank of DIP switches. (See below.) DO NOT adjust the
other DIP switches.
• Turn off the power supply to the water heater before changing the DIP
switch settings.
• Failure to observe these warnings could lead to carbon monoxide poison-
ing, severe personal injury, or death.
• There are two systems for freeze protection in the water heater-heating block system and recircula-
tion system with the integrated pump.
• This water heater comes equipped with heating blocks to protect the unit against damages associated
with freezing. When the freeze protection thermostat senses air temperature below 36.5 °F (2.5 °C),
the blocks will heat up to prevent freezing of the unit.
• This water heater can recirculate the water in the pipes installed in the recirculation system with the
integrated pump to prevent freezing. When the integrated thermistors detect water temperature below
50
°F (10 °C), the pump will activate and recirculate the water in the recirculation line.*
• To operate these freeze protection systems, there has to be electrical power to the unit. Damage
to the heat exchanger caused by freezing temperatures due to power loss is not covered under the
warranty. In cases where power losses can occur, consider the use of a backup power supply.
• In any areas subject to freezing temperatures, the manufacturer highly recommends an indoor installa-
tion with an indoor model.
• The manufacturer also highly recommends the use of a backflow preventer (sold separately) to mini-
mize the amount of cold air entering through the exhaust venting when the water heater is off.
• It is the installer’s responsibility to be aware of freezing issues and take all preventative measures. The
manufacturer will not be responsible for any damage to the heat exchanger as a result of freezing.
• If you will not be using your heater for a long period of time:
1. Completely drain the water out of the unit. Refer to p. 63.
2. Disconnect power to your heater.
This will keep your unit from freezing and being damaged.
*Recirculation system for freeze protection is only activated when the built-in/remote controller is off.
When the integrated thermistors detect the water temperature above 52 °F (11 °C) over five minutes,
the
operation is deactivated. If you want to stop the recirculation system for freeze protection, change
the DIP switch setting below.
Pump operation
for freeze protection
Active Inactive
1 2 3 4
ON
No.4 : OFF
1 2 3 4
ON
No.4 : ON
DEFAULT
Middle bank
of DIP switches
Lower bank of
DIP switches
Upper bank of
DIP switches
Normal Operaon
Owner's Guide
FREEZE PROTECTION SYSTEM
Only pipes within the water heater are protected by the freeze protection system. Any
water pipes (hot or cold) located outside the unit will not be protected. Properly protect
and insulate these pipes from freezing.
NOTICE
62 Page
MAINTENANCE AND SERVICE
• Turn off the electrical power supply and close the manual gas shutoff valve
and the manual water control valve before servicing.
• Failure to do so could result in severe personal injury, or death.
WARNING
• Clean the cold-water inlet filter. (Refer to the Unit Draining and Filter Cleaning Section on this page.)
• Be sure that all openings for combustion and ventilation air are not blocked.
• The venting system should be checked annually for any leaks, corrosion, blockages or damage.
• The burner should be checked annually for dust, lint, grease or dirt.
• Keep the area around the water heater clear. Remove any combustible materials, gasoline or any
flammable vapors and liquids.
• If the relief valve discharges periodically, it may be due to thermal expansion in a closed water supply
system. Contact the water supplier or local plumbing inspector on how to correct this situation.
• Visually check of burner flames (see below) through the burner window in the burner assembly
located at the middle of the water heater.
Sasfactory
Blue ame
Unsasfactory
Flame
blowing up
Unsasfactory
Red or Yellow
ame
The manufacturer recommends having the unit checked once a year or as necessary by a licensed
technician. If repairs are needed, any repairs should be done by a licensed technician.
Normal Operaon
Owner's Guide
Pressure
port
-Measuring inlet gas pressure-
1. Turn off all electric power to the water heater if service is to be performed.
2. Turn the manual gas valve located on the outside of the unit to the off position.
3. Failure to follow these steps could lead to fire or explosion, resulting in personal injury
or death.
WARNING
The water heater cannot perform properly without sufficient inlet gas pressure. Below are instructions
on how to check the inlet gas pressure. THIS IS ONLY TO BE DONE BY A LICENSED PROFESSIONAL.
7. The static and dynamic pressures should be within the
ranges specified on the heater's rating plate and the table
on p. 31.
8. The difference of static to dynamic pressure should not
exceed 1.5" W.C. Pressure drops that exceed 1.5" W.C. can
indicate restricted gas flow, undersized gas lines, and/or
undersized supply regulators. (NOTICE: In Canada, the pres-
sure drops cannot exceed those specified in CSA B149.1.)
9. Measure gas supply pressure at minimum heater operation:
Reduce water flow so the heater is running at minimal oper-
ation. Press the MIN button on the computer board. (Refer
to the diagram.) Take a supply gas pressure reading and
verify that it is within the specified inlet gas pressure range.
1. Shut off the manual gas valve on the gas supply line.
2. Remove the screw from the pressure port which is located on the gas inlet of the water
heater shown in the diagram on the right.
3. Connect the manometer to the pressure port and zero the manometer.
4. Re-open the manual gas valve. Verify that there are no gas leaks.
5. With all gas burning equipment off, take a reading of the static gas pressure and make a
note of it.
6. Measure gas supply pressure at maximum heater operation: Open hot water faucets to cre-
ate maximum flow. Press the MAX button on the computer board. (Refer to the diagrams
below.) Take a reading of the supply dynamic gas pressure with all gas burning equipment
running at maximum rate.
540P Computer board
MAX button
MIN button
63 Page
UNIT DRAINING and FILTER CLEANING
Normal Operaon
Owner's Guide
Water valve
Gas
valve
Drain plug
(Small)
Drain plug
with Filter (Large)
1. Close the manual gas shutoff valve.
2. Turn off power to the unit and wait a couple of seconds. Turn
on again.
3. Wait 30 seconds, and then turn off power to the unit.
4. Close the inlet water valve.
• If the heater is part of an Easy-Link or Multi-Unit System,
close the inlet and outlet water valves to isolate the heater.
Then proceed to step 6.
5. Open all hot water taps in the house. When the residual
water flow has ceased, close all hot water taps.
6. Have a bucket or pan to catch the water from the unit’s drain
plugs. If Isolation valves are installed, open the drains to drain
the water. If isolation valves are not installed, unscrew the
two drain plugs (large and small) to drain all the water out of
the unit. Do not lose the o-rings that will be on the two drain
plugs.
7. Wait a few minutes to ensure all water has completely drained
from the unit.
8. Clean the filter: Check the water filter located within the cold
inlet. With a tiny brush, clean the water filter of any debris
which may have accumulated and reinsert the filter back into
the cold water inlet.
9. Securely screw the drain plugs back into place.
Hand- tighten only.
64 Page
TROUBLESHOOTING
GENERAL
PROBLEM SOLUTIONS
TEMPERATURE and AMOUNT OF HOT WATER
It takes a long time to
get hot water at the
fixtures.
• Check to see if a recirculation timer is active. If not, it will take time for
the hot water to get from the heater to the fixture.
• Check the recirculation pump for proper flow.
• The inlet filters on the return and inlet connections may need to be
cleaned.
The water is not hot
enough.
• Compare the flow and temperature. See the charts on p. 76.
• Check cross plumbing between cold water lines and hot water lines.
• Is the gas supply valve open fully? (p. 44)
• Is the gas line sized properly? (p. 31)
• Is the gas supply pressure sufficient? (pp. 31 and 62)
• Is the set temperature set too low? (pp. 51 and 60)
The water is too hot. • Is the set temperature set too high? (pp. 51 and 60)
The hot water is not
available when a
fixture is opened.
• Make sure the unit has 120 VAC, 60 Hz power supply.
• If you are using the remote controller and/or temperature controller, is
the power button turned on?
• Is the gas supply valve open fully? (p. 44)
• Is the water supply valve open fully? (p. 44)
• Is the filter on the cold water inlet and return connection clean? (p. 63)
• Is the hot water fixture sufficiently open to draw at least 0.5 GPM
(1.9 L/min) through the water heater? (p. 50)
• Is the unit frozen? (p. 61)
• Is there enough gas in the tank / cylinder? (For Propane model)
The hot water turns
cold and stays cold.
• Is the flow rate enough to keep the water heater running? (p. 50)
• If there is a recirculation system installed, does the recirculation line have
enough check valves? (p. 33)
• Is the gas supply valve open fully? (p. 44)
• Is the filter on the cold water inlet and return connection clean? (p. 63)
• Are the fixtures clean of debris and obstructions?
• Check if the flow rate is too low. (p. 50)
Fluctuation in hot
water temperature.
• Is the filter on the cold water inlet and return connection clean? (p. 63)
• Is the gas line sized properly? (p. 31)
• Is the supply gas pressure sufficient? (pp. 31 and 62)
• Check for cross connection between cold water lines and hot water lines.
Troubleshoong
Owner's Guide
65 Page
PROBLEM SOLUTIONS
WATER HEATER
Unit does not ignite
when water goes
through the unit.
• Is the flow rate over 0.5 GPM (1.9 L/min)? (p. 50)
• Is the filter on cold water inlet and return connection clean? (p. 63)
• Check for reverse connection and cross connection.
• If you use the remote controller and/or built-in controller, is the
power button turned on?
• Check if the inlet temperature is too high.
The fan motor is
still spinning after
operation has stopped.
• This is normal. After operation has stopped, the fan motor keeps
running from 15 to 70 seconds in order to re-ignite quickly, as well
as purge all the exhaust gas out of the flue.
Unit sounds abnormal
while in operation
• Contact the manufacturer at 1-877-737-2840 (USA)
1-888-479-8324 (Canada)
BUILT-IN CONTROLLER AND
REMOTE CONTROLLER
Controller does not
display anything when
the power button is
turned on.
• Make sure the unit is supplied with power.
• Make sure the connection to the unit is correct. (pp. 38 and 39)
NOTICE:
When the unit has not operated for five minutes or more, the display
of the controllers turns off to conserve energy.
Although the controller of the parent unit will display the set
temperature at the Easy-Link System, the controller of the child unit
will not display the set temperature.
An ERROR code is
displayed.
• Please see pp. 68 and 69.
EASY-LINK SYSTEM
How are the unit
numbers assigned?
• For an Easy-Link System, the Parent unit is always labeled #1 and all
other subsequent Child units are numbered randomly.
• To check which numbers are assigned to which Child units, push
the button on the computer board of any Child unit as shown
below. The unit number will be displayed on the built-in controller
of the Child unit and/or the remote controller of the Child unit, if
installed. (Refer to pp. 40 and 41.)
When the remote
controller turned
ON, STAND BY LED
is lit.
Temperature controller
Troubleshoong
Owner's Guide
Buon to check unit numbers
Child units : 540 models
66 Page
Troubleshoong
Owner's Guide
Error code
ERROR CODES
-General-
• The units have self-diagnostic functions for safety and convenience when troubleshooting.
• If there is a problem with the installation or the unit, the error code will be displayed on the built-in
controller or remote controller.
• Consult the table on the following pages for the description of each error code.
-Single unit Installaons-
Example: If your unit has the “321” error code (which signifies an inlet thermistor failure)
• Indicator on the built-in controller
and/or remote controller: “321” will be displayed
on the screen in its entirety.
• Green LED on the computer board: The green LED on the computer board will indicate this code with
two flashes every 1/2 second. The pattern will repeat with a three second delay between patterns.
Error code Green LED
on on on on
on on
off off off off off
321
Error Indication
540P computer board
Green LED ashes to indicate error code.
Error code indicator on
the built-in controller
Error code indicator on
the remote controller
Error Code
on the temperature
controller
Green LED
The number
of flashes
Flash paern
031 701 711
One
311 321 331 341
351 391 441
Two
111 121
Three
611 631 651 661
Four
101 941 991
Five
510 551 721
Six
on on
off
off
0.5 sec. on, O.5 sec. off 3 sec. off
67 Page
*If the 540P Indoor model is the
PARENT unit and the remote controller
is connected to the unit, the remote
controller has priority over the built-in
controller.
-How error codes display in an Easy-Link System-
Error codes will be displayed differently with units installed in an Easy-Link System. It will show both the
error code and which unit has the error code. Below is an example of how the error code of "321" is
displayed in an Easy-Link System.
Example: Unit #2 with a “321” error code (inlet thermistor failure)
• Indicator on the built-in controller
and/or remote controller of Parent unit*:
“321” and "2" will alternately flash on
the display.
Unit #Error code
Outdoor model installation
• Unit #2:
The green LED on the computer board will flash
twice, just like in the single unit example.
• Unit #3 and #4:
The green LED on the computer board will stay
off.
Indoor model installation
• Unit #2:
"321" will flash on
the display. The green LED on
the computer board will be flashing
twice, just like in the single
unit example.
• Unit #3 and #4:
These units will not display anything,
as the error code does not pertain to them.
Unit #1
PARENT
Unit #2
CHILD
Unit #4
CHILD
Unit #3
CHILD
100276687
(TM-RE43)
540P 540 540 540
Error code Green LED
on on on on
on on
off off off off off
321
100276687
(TM-RE43)
Unit #1
PARENT
Unit #2
CHILD
Unit #3
CHILD
Unit #4
CHILD
Green LED on
the computer board
540P 540 540 540
Troubleshoong
Owner's Guide
68 Page
-Fault analysis-
If the error code is displayed on the computer board of the water heater or remote controller and/or
temperature controller, please check the following. After checking, consult with the manufacturer.
Troubleshoong
Owner's Guide
Remote
Green
LED
Malfunction
description
Diagnosis
031
One
Time
Incorrect DIP
switch setting
• Check the DIP switch settings on the PCB (Part #701).
101
Five
Times
Warning for the
“991” error code
• Check the gas type of the water heater.
• Inspect the environment around the water heater. Determine how
long the unit has been installed.
• Check the altitude/elevation of the area where the water heater is
installed.
• Check if there is any blockage in the intake air and/or exhaust.
• If the water heater is installed as a direct-vent system, check wheth-
er there is enough distance between the intake air terminal and the
exhaust terminal.
• Check if there is grease and/or dirt in the burner (Part #101) and the
fan motor (Part #103), especially if the water heater has been installed
in a contaminated area.
111
Three
Times
Ignition failure
• Check if the Hi-limit switch (Part #412) is properly functioning.
• Check for connection/breakage of wires (Part #413, 708, 709, 711), burn
marks on the computer board (Part #701), and/or soot on the flame rod
(Part #108).
• Check if there is a buzzing spark ignition sound coming from the
burner (Part #101) when water heater prepares for combustion.
• Listen for the double “clunk” sound coming from gas valve assembly
(Part #102) when water heater goes into combustion.
• Check if there is leaking from heat exchanger (Part #401).
121
Three
Times
Loss of flame
• Check if the Hi-limit switch (Part #412) is functioning properly.
• Check for connection/breakage of wires (Part #413, 708, 709, 711),
burn marks on the computer board (Part #701), and/or soot on the
flame rod (Part #108).
• Check if there is leaking from heat exchanger (Part #401).
311
Two
Times
Heat exchanger
thermistor failure
• Check for connection/breakage of wires and/or debris on thermis-
tor (Part #407, 408, 411, 715, 718, 731).
321
Two
Times
Inlet thermistor
failure
331
Two
Times
Outlet thermistor
failure
341
Two
Times
Exhaust
thermistor failure
(Indoor model only)
351
Two
Times
Return Thermistor
Failure
391
Two
Times
Air-fuel ratio rod
failure
• Check for connection/breakage of wires (Part #709) and/or soot on
the AFR rod (Part #108).
441
Two
Times
Flow sensor
failure
• Check for connection/breakage of wires and/or debris on the flow
sensor impeller (Part #402).
510
Six
Times
Abnormal main
gas solenoid valve
• Check for connection/breakage of wires (Part #708) and/or burn marks
on the computer board (Part #701).
551
Six
Times
Abnormal gas
solenoid valve
• Check for connection/breakage of wires (Part #708) and/or burn marks
on the computer board (Part #701).
69 Page
Troubleshoong
Owner's Guide
Remote
Green
LED
Malfunction
description
Diagnosis
611
Four
Times
Fan motor fault
• Check for connection/breakage of wires, dust buildup in the fan
motor (Part #103) and/or burn marks on the computer board
(Part #701).
• Check for frozen/corrosion of connectors (Part #103).
631
Four
Times
Pump fault
• Check for connection/breakage of wires in the pump(Part #726).
• Check if the water in the pump has frozen (Part #726).
651
Four
Times
Flow adjustment
valve fault (Easy-
Link System only)
• Inspect the flow adjustment valve (Part #402), for connection/
breakage of wires, locked motor drive due to scale buildup, and/
or water leakage.
661
Four
Times
Bypass valve fault
• Inspect the bypass valve (Part #403), for connection/breakage
of wires, locked motor drive due to scale buildup, and/or water
leakage.
701
One
Time
Computer board fault
• Check for connection/breakage of wires (Part #714).
711
One
Time
Gas solenoid valve
drive circuit failure
• Refer to the 111 and 121 error codes.
721
Six
Times
False flame
detection
• Check if there is leaking from heat exchanger (Part #401).
741
N/A Miscommunication
between water
heater and remote
controller
• Check the model type of the remote controller.
• Inspect the connections between the water heater and remote
controller.
• Check the power supply of the water heater.
751
N/A Miscommunication
between water
heater and built-in
controller (Indoor
model only)
• Inspect the connections between the water heater and built-in
controller.
• Check the power supply of the water heater.
761
N/A Miscommunication
in Easy-Link System
• Check if the connections between the parent unit and the child
units are correct. Refer to pp. 40 and 41.
941
Five
Times
Abnormal exhaust
temperature
(Indoor model only)
• Check if the inlet and return water temperature is higher than
140°F (60°C) in the recirculation system.
991
Five
Times
Imperfect
combustion
• Check the gas type of the water heater.
• Inspect the environment around the water heater. Determine
how long the unit has been installed.
• Check the altitude/elevation of the area where the water heater
is installed.
• Check if there is any blockage in the intake air and/or exhaust.
• If the water heater is installed as a direct-vent system, check
whether there is enough distance between the intake air terminal
and the exhaust terminal.
• Check if there is grease and/or dirt in the burner (Part #101) and
the fan motor (Part #103), especially if the water heater has been
installed in a contaminated area.
70 Page
COMPONENTS DIAGRAM
Indoor model
Outdoor model
Case assembly
Temperature
remote controller
723
722
056
002
050
050
717
052
008
052
067
704
702
001
004
002
717
004
052
052
003
419
007
713
052
725
001
702
006
005
052
Built-in controller
Indoor model
Components Diagram
Owner's Guide
724
71 Page
Computer board assembly
Surge box assembly
Components Diagram
Owner's Guide
708
713
711
709
103
707
722
715
402
714
402
715
721
715
726
701
716
121
713
706
703
72 Page
Components Diagram
Owner's Guide
Burner assembly
101
104
115
106
107
108
110
109
111
711
112
062
053
053
709
053
053
401
103
105
065
054
113
102
708
119
151
118
055
051
150
057
055
711
063
121
707
714
719
117
062
066
709
730
117
053
116
114
Manifold
assembly
Burner assembly
73 Page
Components Diagram
Owner's Guide
Water way assembly
D
A
B
E
E
F
F
C
B
A
D
C
H
403
456
460
458
462
473
064
412
058
468
462
468
064
473
467
462
462
451
414
459
454
463
407
463
455
465
466
458
462
052
409
408
454
417
410
455
451
415
451
415
052
469
455
464
416
450
414
459
454
411
401
718
053
418
152
153
472
418
415
009
052
471
470
402
460
456
461
404
733
460
456
458
729
458
462
417
059
454
732
457
406
052
405
728
451
734
456
460
456
735
451
734
727
726
461
404
458
052
405
457
406
059
454
731
G
G
H
Water inlet secon
Pump secon
Water outlet secon
Bypass secon
461
458
419
067
413
453
452
74 Page
PARTS LIST
Item # Description
Part #
540P
(AT-H3P)
001 Case assembly for Indoor model
for Outdoor model
N/A
N/A
EK617
EK635
002 Front cover for 540P Indoor
for 540P Outdoor
100074665
100074666
EK158
EK174
003
004
005
006
007
Intake air port assembly
Bracket
Junction box
Power supply cord assembly
Back guard panel
100074667
N/A
100074668
100276679
N/A
EK170
EK162
EK190
EK637
EK161
008
009
Chamber fixing plate
Condensate drain port
N/A
100074203
EK160
EKH23
050
051
052
053
Truss screw M4×12 (W/Washer) SUS410
Truss screw M4×10 (W/Washer) SUS410
Truss screw M4×10 (Coated) SUS3
Truss screw M4x10 SUS
100074210
100074509
100074211
100074245
EW000
EW001
EW002
EW003
054
055
056
057
Hex head screw M4×12 (W/Washer) SUS3
Hex head screw M4x8 FEZN
Pan screw M4x20 SUS410
Tap tight screw M4x12 FEZN
100074510
100074248
N/A
100074385
EW004
EW005
EW018
EKK31
058
059
060
061
Tapping screw M3x6 SUS3 Pan head
Tapping screw M4x6 SUS3 Truss head
Tap tight screw M4x12
Plus bind Screw M3x6 FEZN
100074272
100074512
100076269
N/A
EW00A
EW009
EKK37
EK191
062
063
064
065
066
067
Pan screw M4x8 MFZN
Wire clamp 60
Screw M4x10
Screw M3x6 SUS3 Binding head
Pan screw M4x10
Pan screw M4x10 for 3" adapter
100074244
100074233
N/A
100074514
100074247
N/A
EW00D
EM167
EK230
EW00B
EW006
EK739
101
102
Burner assembly
Manifold with gas valve assembly LP
Manifold with gas valve assembly NA
100074670
100074671
100074672
EK192
EK181
EK182
103 Fan motor for Indoor model
Fan motor for Outdoor model
100074606
100074228
EK109
EKK25
104
105
106
107
Burner gasket
Fan damper for Indoor model
Burner window
Rod holder gasket
100074216
100074466
100074218
100074219
EKK2X
EM381
EKK2V
EKK2W
108
109
110
111
Flame rod
Igniter rod
Rod holder
Rod cap
100074673
100074222
100074221
100074223
EK193
EKK0F
EKK32
EKN61
112
113
114
115
Burner damper LP
Burner damper NA
Manifold gasket A
Manifold gasket B
Burner holder gasket
100074674
100074675
100074229
100074230
100074217
EK183
EK169
EKK2Y
EKK2K
EKK0G
116
117
118
Pressure port
Combustion chamber tube
Gas inlet
100074227
100074528
100074616
EKK2D
EX019
EK117
119
121
Gas inlet ring
Surge box plate
100074526
N/A
EX00D
EK618
150
151
152
153
O-ring P18 NBR (Black)
O-ring P20 NBR (Black)
Silicon ring for Outdoor model
Exhaust port for Outdoor model
100074533
100074242
100074678
100074679
EZP18
EK042
EK157
EK177
Parts List
Owner's Guide
75 Page
Parts List
Owner's Guide
Item # Description
Part #
540P
(AT-H3P)
401 Primary heat exchanger assembly for 540P model 100276637 EK621
402
403
404
405
406
Flow adjustment valve / Flow sensor
Bypass valve
Water inlet
Inlet drain plug
Inlet water filter
100074624
100074625
100074377
100074381
100074382
EK129
EKD58
EKK1U
EKK2B
EKK2C
407 Inlet thermistor 100276682 EK641
408 Outlet thermistor 100074374 EKK1A
409
410
411
Water outlet
Outlet drain plug
Heat exchanger thermistor
100074681
100074383
100074281
EK208
EKK2E
EKK2T
412 Hi-Limit switch 100074280 EKN34
413
414
Overheat-cut-off fuse
Pipe heater
100074334
100074682
EK333
EK209
415 Inlet heater for Indoor model
Inlet heater for Outdoor model
100074683
100074684
EK210
EK211
416
417
Drain tube
Inlet heater
100074685
100074629
EK231
EK105
418
419
Secondary heat exchanger for Indoor model
Secondary heat exchanger for Outdoor model
3" PVC adapter
100074700
100074701
100310706
EK251
EK256
EK737
450
451
452
453
Pipe heater fixing plate
Heater fixing plate 16
Fuse fixing plate 18
Fuse fixing plate 14
100074273
100074310
100074251
100074331
EKK27
EK031
EKK26
EK029
454
455
456
457
O-ring P4 FKM
O-ring P6 FKM
O-ring P14 FKM
O-ring P15 FKM
100076303
100076305
100076306
100076307
EZM04
EZM06
EZM14
EZM15
458
459
460
461
O-ring P16 FKM
Fastener “4-11”
Fastener “14-22”
Fastener “16A”
100076308
100074282
100074290
100074410
EZM16
EKH30
EKK24
EM192
462
463
464
465
Fastener “16-25A”
Fastener “6-15”
Flat heater
Drain tube
100074389
100074297
100074686
100276674
EKK39
EX12K
EK217
EK625
466 Cold pipe 100276640 EK624
467
468
469
470
Stainless heat exchanger out pipe
Header connection
Drain port
Thermistor fixing plate
100074690
100074691
100074692
100074291
EK222
EK226
EK228
EX13H
471
472
473
Exhaust thermistor gasket
Hi-limit switch for exhaust
Gasket
100074296
100074289
100074693
EX13L
EKH6G
EK229
701 Computer board 100276677 EK628
702
703
704
Rubber grommet
Surge box
120 VAC wire for Indoor model
100076470
100076100
100074601
EX00B
EK280
EK146
706
707
708
120 VAC Power ON-OFF switch
Remote controller wire
Gas valve wire
100074326
100074650
N/A
EKK4V
EK165
EK633
709
711
Flame rod wire
Igniter assembly
N/A
100276678
EK634
EK630
76 Page
OUTPUT TEMPERATURE CHART
Chart is based on properly sized gas line.
540P model
100
(38)
105
(40)
110
(43)
115
(45)
120
(50)
125
(52)
130
(55)
135
(57)
140
(60)
40°F（4℃）
6.3 5.8 5.4 5.0 4.7 4.4 4.2 4.0 3.8
50°F（10℃ ）
7.6 6.9 6.3 5.8 5.4 5.0 4.7 4.4 4.2
60°F（16℃ ）
9.5 8.4 7.6 6.9 6.3 5.8 5.4 5.0 4.7
70°F（21℃ ）
10.0 10.0 9.5 8.4 7.6 6.9 6.3 5.8 5.4
0.0
2.0
4.0
6.0
8.0
10.0
12.0
Output hot water GPM
40°F（4℃） 50°F（10℃） 60°F（16℃） 70°F（21℃）
30
45
Set temp.
℉（℃）
Incoming temp.
℉（℃）
(L/M)
(23.9) (22.0) (20.4) (19.1) (17.9) (16.8) (15.9) (15.1) (14.3)
(28.6) (26.0) (23.9) (22.0) (20.4) (19.1) (17.9) (16.8) (15.9)
(35.8) (31.8) (28.6) (26.0) (23.9) (22.0) (20.4) (19.1) (17.9)
(37.9) (37.9) (35.8) (31.8) (28.6) (26.0) (23.9) (22.0) (20.4)
15
*When the set temperature is 130 °F (55 °C) or higher, maximum flow rate is limited to 8.0 GPM.
Output Temperature vs. GPM (Max. 10.0 GPM) with Various Inlet Water Temperature
Parts List
Owner's Guide
5M2051-2
2000536265
(REV. C)
Item # Description
Part #
540P
(AT-H3P)
713 Switch wire with thermostat for Indoor model
for Outdoor model
N/A
N/A
EK631
EK636
714
715
716
717
Proportional gas valve wire
24V cables for Indoor model
for Outdoor model
Computer board cover
Cable clamp
100074657
N/A
N/A
100074375
N/A
EK167
EK632
EK638
EKK1M
EX13C
718
719
721
722
723
Exhaust thermistor for Indoor model
Remote fixing plate
Exhaust Hi-limit switch wire
Temperature controller for Indoor model
Fixing plate
100074316
100074644
100074659
100276680
N/A
EKH6E
EK152
EK180
EK639
EK629
724
725
726
Temperature remote controller
Pump fixing plate
Recirculation pump assembly
100276687
N/A
100276636
TM-RE43
EK619
EK620
727
728
729
Pump inlet pipe
Pump outlet pipe
Pump connection
100276638
100276639
100276676
EK622
EK623
EK626
730
731
732
PCB fixing plate
Return thermistor
Closing plug
N/A
100276681
100276683
EK627
EK640
EK642
733
734
735
Three way connection
Heater
Fastener "12.7"
100276686
100076326
100076400
EK643
EK469
EM190
