AO Smith GCF-50 101 ProLine XE 50-Gallon High Efficiency Tall Liquid Propane Gas Water Heater

Product's Documents

Below are documents related to this product, you can read online or download:
User Manual Specification
  • Spec Sheet - ProLine® XE Flue Damper Spec Sheet (AOSRG45250) - (English) Download
GCF-50 101 photo

Manual - Residential Gas Water Heater with FVIR - Manual

This is the main product document for model GCF-50 101. Additionally, the document applies to other AO Smith models: GCF-50

The file format is pdf, 40 pages, you can download this manual here .

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Installaon Instrucons and
Use & Care Guide
Keep this manual in the pocket on heater for future reference whenever maintenance, adjustment or service is required.
Retain your original receipt as proof of purchase.
DO NOT RETURN THIS UNIT TO THE STORE
Read this manual and the labels on the water heater before you install,
operate, or service it. If you have diculty following the direcons, or
aren’t sure you can safely and properly do any of this work yourself:
Call your Local plumbing supplies store to have this water heater installed.
Professional Installaon is available for this product and the work is guaranteed.
Schedule an appointment with a qualied person to install your water heater.
• Call our Technical Assistance Hotline which is listed on the water heater’s
warranty sheet. We can help you with installaon, operaons, troubleshoong,
or maintenance. Before you call, write down the model and serial number from
the water heater’s data plate.
Incorrect installaon, operaon, or service can damage the water heater, your
house and other property, and present risks including re, scalding, electric shock,
and explosion, causing serious injury or death.
Residenal Gas
Water Heater
with the Flammable Vapor Ignion Resistant Safety System
Not for use in Manufactured (Mobile) Homes
100400765_2000621411
Do not store or use gasoline or other
ammable vapors and liquids in the
vicinity of this or any other appliance.
WHAT TO DO IF YOU SMELL GAS
Do not try to light any appliance.
Do not touch any electrical switch;
do not use any phone in your build-
ing.
Immediately call your gas supplier
from a neighbors phone. Follow the
gas suppliers instrucons.
If you cannot reach your gas suppli-
er, call the re department.
Installaon and service must be per-
formed by a qualied installer, service
agency or the gas supplier.
WARNING: If the informaon in
these instrucons is not followed
exactly, a re or explosion may
result causing property damage,
personal injury or death.
November 2025
Table of Contents
Important Safety Informaon .................................................. 3
Geng Started ........................................................................ 7
Installaon ............................................................................. 13
Installaon ............................................................................. 21
Operaon .............................................................................. 22
Troubleshoong .................................................................... 25
Maintenance ......................................................................... 30
Repair Parts ........................................................................... 37
LOW LEAD
CONTENT
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2 • Residenal Gas Water Heater Use and Care Guide
COMPLETED INSTALLATION (TYPICAL)
To Vent Termination
On Roof
Vent Pipe
Cold Inlet
Hot Outlet
Inlet Water
Shut-off Valve
Thermal
Expansion Tank
Temperature and Pressure
Relief Valve
Discharge Pipe
Drain Valve
Floor Drain
Drain Pan
Drip Leg
Manual Gas
Shut-off
Gas Control Valve/
Thermostat
Draft Hood
Gas Supply
Piping
Transformer
Ground Joint Union
TCO SWITCH
Flue Damper
NOTICE: If copper piping is used, then unions must be dielectric at inlet and outlet.
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Residenal Gas Water Heater Use and Care Guide • 3
IMPORTANT SAFETY INFORMATION
SAFETY
Read and follow all safety messages and instrucons in this
manual.
This is the safety alert symbol. It is used to alert you to
potenal physical injury hazards. Obey all safety messages
that follow this symbol to avoid possible property damage,
serious injury or death. Do not remove any permanent
instrucons, labels, or the data plate from either the outside
of the water heater or on the inside of the access panels. Keep this manual
near the water heater.
WARNING! If the informaon in these instrucons is not followed
exactly, a re or explosion may result causing property damage, personal
injury or death. Do not store or use gasoline or other ammable vapors and
liquids in the vicinity of this or any other appliance.
An odorant is added by the gas supplier to the gas used by this water heater.
This odorant may fade over an extended period of me. Do not depend upon
this odorant as an indicaon of leaking gas. We recommend installing a fuel
gas and carbon monoxide detector.
This product is cered to comply with a maximum weighted average of
0.25% lead content as required in some areas.
DANGER indicates a hazardous
situaon that, if not avoided, will
result in death or serious injury.
WARNING indicates a hazardous
situaon that, if not avoided, could
result in death or serious injury.
CAUTION indicates a hazardous
situaon that, if not avoided, could
result in minor or moderate injury.
NOTICE indicates pracces not
related to physical injury.
DANGER
WARNING
CAUTION
NOTICE
*Drain and flush tank, clean condensate
pan, and remove and inspect anode
rod after first six months of operation
and at least annually thereafter. Inspect
and operate the Temperature and
Pressure Relief Valve (T&P) annually
(see the label on the T&P valve for
maintenance schedule). If no label is
attached to the T&P Relief Valve, follow
the instructions in the T&P Relief Valve
Maintenance section of this manual.
See the Maintenance section for more
information about maintaining this
water heater.
Important informaon to keep
Fill out this secon and keep this manual
in the pocket of the water heater for
reference.
Date Purchased:
Model Number:
Serial number:
Maintenance performed:* Date:
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4 • Residenal Gas Water Heater Use and Care Guide
To reduce the risk of property
damage, serious injury or death, read
and follow the precauons below,
all labels on the water heater, and
the safety messages and instrucons
throughout this manual.
RISKS DURING
INSTALLATION AND
MAINTENANCE
Liing Risk
WARNING! The
water heater is
heavy. Follow these
precauons to reduce the risk of
property damage, injuries from liing
or impact injuries from dropping the
water heater.
Use at least two people to li the
water heater.
Be sure you both have a good grip
before liing.
Use an appliance dolly or hand truck
to move the water heater.
Explosion Risk
WARNING! Read the
water heater’s data
plate to determine the type of gas
required. Failure to follow these
instrucons can result in serious
injury or death from explosion, re
or carbon monoxide poisoning.
Do not connect a natural gas water
heater to an L.P. gas supply.
Do not connect an L.P. gas water
heater to a natural gas supply.
Use a new CSA approved gas supply
line.
Install a shut-o valve on the gas
supply line.
Gas Pressure
WARNING! The gas supply
pressure must not exceed the
maximum supply pressure as stated
on the water heaters data plate. The
minimum supply pressure is for the
purpose of input adjustment. L.P.
gas supply pressure must not exceed
13” water column. Have a qualied
person (licensed plumber, gas
company personnel, or authorized
service technician) check for proper
L.P. gas pressure. L.P. gas pressures
exceeding 13” water column can
result in serious injury or death from
explosion or re.
RISKS DURING
OPERATION
Scalding Risk
This water heater
can make water hot
enough to cause
severe burns instantly, resulng in
severe injury or death.
Feel water before bathing or show-
ering.
To reduce the risk of scalding, install
Thermostac Mixing Valves (tem-
perature liming valves) at each
point-of-use. These valves automa-
cally mix hot and cold water to limit
the temperature at the tap. Mixing
valves are available at your local
plumbing supplier. Follow the man-
ufacturers instrucons for installa-
on and adjustment of the valves.
The gas control valve on this water
heater has been factory set to its
lowest seng to reduce the risk
of scalding. Higher temperatures
increase the risk of scalding, but even
at 120°F, hot water can scald. If you
choose a higher temperature seng,
Thermostac Mixing Valves located
at each point-of-use are parcularly
important to help avoid scalding.
Table 1:
Temperature Time to Produce a
Serious Burn
120°F (49°C) More than 5 minutes
125°F (52°C) 1-½ to 2 minutes
130°F (54°C) About 30 seconds
135°F (57°C) About 10 seconds
140°F (60°C) Less than 5 seconds
145°F (63°C) Less than 3 seconds
150°F (66°C) About 1-½ seconds
155°F (68°C) About 1 second
For more informaon about changing
the factory temperature seng, refer
to the “Adjusng the Temperature”
secon in this manual (page 23).
Even if you set the water heaters gas
control valve to a low seng, higher
water temperatures may occur in
certain circumstances.
• In some cases, repeated small draws
of water can cause the hot and cold
water in the tank to “stack” in layers.
If this happens, the water can be as
much as thirty degrees hoer than
the gas control valve seng. This
temperature variaon is the result
of your usage paern and is not a
malfuncon.
Water temperature will be hoer if
someone adjusted the gas control
valve to a higher seng.
Problems with the gas control valve
or other malfuncons may result in
higher than expected water tem-
peratures.
• If the water heater is in a hot envi-
ronment, the water in the tank can
become as hot as the surrounding
air, regardless of the temperature
seng.
• If the water supplied to the water
heater is pre-heated (by a solar
heang system) the temperature
in the tank may be higher than the
water heater’s temperature seng.
SAFETY
IMPORTANT SAFETY INFORMATION
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Residenal Gas Water Heater Use and Care Guide • 5
IMPORTANT SAFETY INFORMATION
SAFETY
Should overheang occur or the
burner fail to shut o, turn o the
manual gas supply valve to the
water heater and call a qualied
person.
To reduce the risk of unusually hot
water reaching the xtures in the
house, install Thermostac Mixing
Valves at each point-of-use.
If anyone in your home is at parcular
risk of scalding (for example, the
elderly, children, or people with
disabilies) or if there is a local code
or state law requiring a certain water
temperature at the hot water tap,
these precauons are parcularly
important.
According to a naonal standard
American Society of Sanitary
Engineering (ASSE 1070) and most
local plumbing codes, the water
heater’s thermostat should not be
used as the sole means to regulate
water temperature and avoid scalds.
Properly adjusted Thermostac
Mixing Valves installed at each
point-of-use allow you to set the
tank temperature to a higher seng
without increasing the risk of scalds. A
higher temperature seng allows the
tank to provide much more hot water
and can help provide proper water
temperatures for appliances such as
dishwashers and washing machines.
Higher tank temperatures (140°F) also
kill bacteria that cause a condion
known as “smelly water” and can
reduce the levels of bacteria that
cause water-borne diseases.
Water Contaminaon Risk
Do not use chemicals that could
contaminate the potable water supply.
Do not use piping that has been
treated with chromates, boiler seal, or
other chemicals.
Fire Risk
This water heater
is equipped with a
Flammable Vapor Ignion Resistance
(FVIR) system. FVIR is designed to
reduce the risk of ammable vapor-
related res. FVIR makes this product
more sensive to installaon errors or
improper installaon environments.
The FVIR system will not prevent a
possible re/explosion if ammable
vapors have accumulated in the
combuson chamber and the water
heater is lit.
Do not aempt to light this appliance
by any means if you suspect
ammable vapors have accumulated
inside or outside the appliance.
Immediately call a qualied person to
inspect the appliance. Water heaters
subjected to a ammable vapors
incident will show a discoloraon
on the ame arrestor and require
replacement of the enre water
heater. Improper installaon or an
inadequate air supply can also cause
the FVIR system to disable the water
heater.
WARNING! This water heater has
a reseable thermal switch installed
as part of the FVIR system. Do not
aempt to disable or modify this
feature in any way. Doing so can
lead to re, explosion or excessive
and abnormal producon of carbon
monoxide.
To reduce the risk of a re that could
result in property damage, or serious
injury or death:
Do not store things that can burn
easily such as paper or clothes next
to the water heater.
Do not store or use gasoline or other
ammable substances in the vicinity
of this or any other appliance.
• Keep the water heater from becom-
ing wet. Immediately shut o the
water heater and have it inspected
by a qualied person if you nd
that the wiring, gas control valve/
thermostat or surrounding insula-
on have been exposed to water in
any way (e.g., leaks from plumbing,
leaks from the water heater itself
can damage property and could
cause a re risk). If the water heater
is subjected to ood condions or
the gas control valve/thermostat has
been submerged in water, the enre
water heater must be replaced.
• Replace the water heaters viewport
if glass is missing or damaged. Re-
pair the combuson chamber door
seals if damaged.
Explosion Risk
High temperatures and
pressures in the water
heater tank can cause an explosion
resulng in property damage, serious
injury or death. A new Temperature
and Pressure (T&P) Relief Valve is
included with your water heater to
reduce risk of explosion by discharging
hot water. Addional temperature and
pressure protecve equipment may
be required by local codes.
A naonally recognized tesng
laboratory maintains public inspecon
of the valve producon process
and ceres that it meets the
requirements for Relief Valves for Hot
Water Supply Systems, ANSI Z21.22.
The T&P Relief Valve’s relief pressure
must not exceed the working pressure
rang of the water heater as stated on
the rang plate.
Maintain the T&P Relief Valve
properly. Follow the maintenance
instrucons provided by the
manufacturer of the T&P Relief Valve
(label aached to T&P Relief Valve).
If no label is aached to the T&P
Relief Valve, follow the instrucons
in the T&P Relief Valve Maintenance
secon of this manual. An explosion
could occur if the T&P Relief Valve
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6 • Residenal Gas Water Heater Use and Care Guide
or discharge pipe is blocked. Do not
cap or plug the T&P Relief Valve or
discharge pipe.
Fire and Explosion Risk if Hot Water
is Not Used for Two Weeks or More.
CAUTION! Hydrogen gas builds up
in a hot water system when it is not
used for a long period (two weeks
or more). Hydrogen gas is extremely
ammable. If the hot water system
has not been used for two weeks or
more, open a hot water faucet for
several minutes at the kitchen sink
before using any electrical appliances
connected to the hot water system.
If hydrogen is present there will
probably be an unusual sound such
as “air” escaping through the pipe
as hot water begins to ow. Do not
smoke or have an open ame or
other ignion source near the faucet
while it is open.
Carbon Monoxide Risk
WARNING! This water heater
operates by burning gas. Carbon
monoxide is a colorless, odorless,
gas that is a by-product of burning
of fuels such as coal, wood,
charcoal, oil, kerosene, propane,
and natural gas. Breathing excessive
and abnormal amounts of carbon
monoxide can cause carbon
monoxide poisoning,
resulng in serious
injury or death. This
water heater must
be supplied with
adequate combuson
air and must be properly vented to
the outdoors. Have a qualied person
(licensed plumber, authorized gas
company personnel, or authorized
service technician) install the venng
system using these installaon
instrucons. When the installaon is
complete, check the venng system
using the instrucons on page 23.
Install a fuel gas and carbon mon-
oxide detector in the living areas of
your home.
Do not install this water heater in
a mobile home or manufactured
housing.
Failure to follow these instrucons
can result in serious injury or death
from carbon monoxide poisoning.
Burn Risk
This water heater’s
venng system can
become hot enough to burn. Do not
touch the venng system while water
heater is on, or unl the water heater
is turned o and venng allowed to
cool.
Before you start, be sure you have
the following tools and supplies:
Plumbing tools and supplies appro-
priate for the type of water pipes in
your home.
Thread sealant tape or pipe joint
compound approved for potable
water.
• For homes with copper pipes, you
may purchase a Gas Water Heater
Hook-Up Kit (available at your local
plumbing supplier) with compres-
sion ngs that do not require
soldering. This kit includes two 12”
ex water lines, one 18” exible gas
line, two nipples, and thread sealant
tape.
For homes with plasc pipe, use
threaded connectors suitable for the
specic type of plasc pipe used:
CPVC or PEX (cross-linked polyeth-
ylene). Do not use PVC pipe.
Non-corrosive gas leak detecon
soluon made from hand dishwash-
ing soap mixed with water (1 part
soap to 15 parts water) or children’s
soap bubbles and a small, so-bris-
tled brush.
• An appliance dolly or hand truck to
move the water heater.
Safety gloves.
Recommended Accessories
• A metal drain pan.
Automac water leak detecon and
shut-o device.
Pressure Reducing Valve.
• Thermal Expansion Tank.
Thermostac Mixing Valves at each
point-of-use.
Fuel gas and carbon monoxide
detector.
Figure 1 - Gas Water Heater Hook-Up Kit
Figure 2 - Install a Pressure Reducing Valve set
to 50 to 60 psi.
SAFETY
IMPORTANT SAFETY INFORMATION
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Residenal Gas Water Heater Use and Care Guide • 7
GETTING STARTED
GETTING STARTED
1
Review all of the instrucons
before you begin work.
Improper installaon can
damage the water heater, your home
and other property, and can present
risks of serious injury or death.
2
This water heater is design-
cered by CSA Internaonal
as a Category I, non-direct
vented water heater which takes its
combuson air either from the
installaon area or from air ducted to
the unit from the outside.
This water heater must be installed
according to all local and state codes
or, in the absence of local and state
codes, the “Naonal Fuel Gas Code”,
ANSI Z223.1 (NFPA 54)-current
edion. This is available from the
following:
CSA America, Inc.
8501 East Pleasant Valley Road
Cleveland, OH 44131
Naonal Fire Protecon Associaon
1 Baerymarch Park
Quincy, MA 02269
Check with local code ocials about
codes governing this installaon.
Have your installaon inspected by a
code ocial to ensure the installaon
meets all local codes.
NOTICE: If you lack the necessary
skills required to properly install this
water heater, or you have diculty
following the instrucons, you should
not proceed but have a qualied
person perform the installaon of this
water heater.
Massachuses code requires this
water heater to be installed in
accordance with Massachuses
248-CMR 2.00 and 248-CMR 5.00:
State Plumbing Code. Other local
and state authories may have
similar requirements or other codes
applicable to the installaon of this
water heater.
Combuson and
Venlaon Air Supply
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 combuson and venlaon.
Consult a qualied person if you are
unsure of the proper way to supply air
to your water heater.
WARNING! This gas water heater
requires and adequate source
of clean air for combuson and
venlaon. Without sucient air,
your water heater will have frequent
pilot outages and may emit excessive
and abnormal amounts of carbon
monoxide.
Before beginning:
Calculate total BTU/HR rang of all
appliances.
To calculate the combuson air and
venlaon required, add up the total
BTU/HR rangs of all gas burning
appliances (e.g., water heaters,
furnaces, clothes dryers) in the same
area.
Your water heaters BTU/HR rang
is on the data plate, located next to
the gas control valve/thermostat.
The BTU/HR rangs should be on the
other appliances’ data plates. If you
have trouble determining the BTU/HR
rangs, contact the manufacturer or
have a qualied person determine the
venlaon requirements.
NOTICE: If you are replacing your
old water heater with one that has a
higher BTU/HR rang, the amount of
venlaon required may be greater.
See the following page for calculaon
examples.
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8 • Residenal Gas Water Heater Use and Care Guide
GETTING STARTED
GETTING STARTED
Example:
Gas Burning Appliance BTU/HR Rang
Gas Water Heater 40,000
Furnace 75,000
Dryer 20,000
Total 135,000
Your Appliances:
Gas Burning Appliance BTU/HR Rang
Gas Water Heater
Total
Table 2 provides examples of
minimum square footage (area)
required for various BTU/HR totals.
Areas used for storage or which
contain large objects containing less
air than is assumed for the room sizes
in Table 2 — see Opon A for more
specic calculaons.
Opon A: Installaon without
outside venlaon (not
recommended)
Venlaon with outside air is
recommended for all installaons.
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 oen 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 venlaon. If you are
unsure if your installaon locaon has
enough venlaon, contact your local
gas ulity company or code ocials
for a safety inspecon.
The following instrucons will help
determine if it may be possible to
install without outside venlaon.
Even if this may be possible, you
will need to conduct the vent dra
test on page 23 when installaon
is nished. If there is not enough
venlaon, you will need to venlate
with outside air.
Check for Chemicals:
Installaons where corrosive
chemicals may be present require
outside air. Air for combuson and
venlaon must be clean and free of
corrosive or acid-forming chemicals
such as sulfur, uorine, and chlorine.
Venlaon with outside air will reduce
these chemicals, but it may not
completely eliminate them. Failure
due to corrosive chemicals is not
covered by the warranty. Examples of
locaons 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.
A1: Calculate the air volume of
the room
Air requirements depend on the size
of the room.
Floor Area (square feet) x Ceiling
Height (feet) = Room Volume (cubic
feet)
If there are large objects in the
room (e.g., refrigerator, furnace,
car), subtract their volume from the
volume of the room to get a beer
esmate of the air available.
Room Volume – Object Volume = Air
Volume
Table 2:
BTU/HR
Input
Minimum Square Feet
with 8’ Ceiling
Typical Room
with 8’ Ceiling
30,000 188 9 x 21
45,000 281 14 x 20
60,000 375 15 x 25
75,000 469 15 x 31
90,000 563 20 x 28
105,000 657 20 x 33
120,000 750 25 x 30
135,000 844 28 x 30
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Residenal Gas Water Heater Use and Care Guide • 9
GETTING STARTED
GETTING STARTED
A2: Calculate required air
volume
A water heater installed in an
unconned ac or garage requires
that the space be at least 50 cubic feet
per 1,000 BTU/HR of the total input
for all gas burning appliances in the
same area.
[Total BTU/HR/1000] x 50 = Cubic feet
of air required.
Example:
(135,000 / 1000) x 50 = 6,750
If the air volume of the room is less
than the required air volume, you
must provide two permanent outside
air openings that draw in sucient air.
Use Opon B.
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 venlaon.
A3: Check that combuson
venlaon is adequate
Because modern homes are oen
well-sealed to prevent dras, a
large room may not provide enough
combuson air without venlaon.
To conrm that your installaon has
enough combuson air, conduct the
vent dra test on page 23 when
installaon is nished.
Opon B: Installaon with
outside venlaon
Venlaon with outside air is
recommended, and for most
installaons, is needed. There may be
exisng venlaon that is adequate,
or you may need to add more
venlaon.
Supplying outside air typically requires
two openings. One opening must be
within 12 inches from the oor and
the second opening must be within
12 inches 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 3. Two openings
must be used when venlang with
air from another room.
B1: Determine type of
venlaon
There are several types of venlaon
that can be used:
1. Direct to outdoors
2. Vercal ducts
3. Horizontal ducts
4. Single opening (not recommend-
ed; must be at least 100 square
inches. Not appropriate for
conned spaces smaller than 50
cubic feet per 1,000 BTU/HR as
calculated in secon A or when
geng air from another room.
5. From a larger room inside the
house (not recommended —
refer to secon A to determine
if the combined volume of the
room may be adequate)
B2: Determine minimum free
area required for each vent
opening
The size of the vent openings depends
on the total BTU/HR rang of all
appliances in the space (use your
calculaon from “Before Beginning”)
and the type of vent used. Table 3
provides the minimum free area for
each vent opening depending on the
type of venlaon.
B3: Calculate minimum size of
vent openings and ducts
The vent cross-seconal 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
grille itself blocks some of the free
area, so the opening may need to be
larger to meet the minimum free area
requirements.
See the following page for examples
instrucng how to calculate the
required cross-seconal area.
Table 3:
Minimum Free Area of Permanent Openings for Venlaon and Combuson
Air Supply — All Air from Outdoors Only.
Based on the total BTU/HR input rang for all gas burning appliances within a
conned space.
Opening Source Minimum Free Area Per Opening (sq. in.)
*Direct to outdoors 1 sq. in. per 4,000 BTU/HR (see Figure 3 on page 10)
Vercal ducts 1 sq. in. per 4,000 BTU/HR (see Figure 4 on page 10)
Horizontal ducts 1 sq. in. per 2,000 BTU/HR (see Figure 5 on page 10)
Single Opening 1 sq. in. per 3,000 BTU/HR (see Figure 6 on page 10)
*These openings connect directly with the outdoors through a venlated ac,
a venlated crawl space, or through an outside wall.
background
10 • Residenal Gas Water Heater Use and Care Guide
Use the following formula to calculate
the required cross-seconal area:
Cross-seconal area = minimum free
area required ÷ percent free area of
covering (in decimals – e.g., 60% = .6).
For example, an installaon area that
requires openings with 100 square
inches of free area would need 134
square inch openings if using metal
louvers rated at 75% free area
(100 sq. in. ÷ .75 = 134 sq. in.).
If you do not know the % free area for
your louver or grille, use the following
values:
For wood louvers or grilles: 20%
For metal louvers or grilles: 60%
Follow these rules to ensure that
vents and ducts provide adequate air
ow:
Each vent opening must be no small-
er than 100 square inches.
Ducts must have the same cross-sec-
onal area as free area of the
opening.
Rectangular ducts must have a
minimum dimension of no less than
three inches.
All screens must have mesh ¼” or
larger.
• Movable louvers must be locked
open or interconnected with the
equipment so that they open auto-
macally during operaon.
Keep louvers and grilles clean and
free of debris or other obstrucons.
B4: Check that air source is
clean and free of chemicals
Air for combuson and venlaon
must be clean and free of corrosive
or ammable chemicals. A failure due
to corrosive chemicals in the air is not
covered by the warranty. Combuson
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.
B5: Check that combuson
venlaon is adequate
To conrm that your installaon has
enough combuson air, conduct the
vent dra test on page 23 when
installaon is nished.
Combuson Air Supply Opons
Figure 3 - Direct to Outdoors Openings
Figure 4 - Vercal Duct Openings
Figure 5 - Horizontal Duct Openings
Figure 6 - Single Opening
Venng
WARNING! Carbon Monoxide
Hazard. This water heater must
be supplied with adequate air and
vented to outdoors. The vent system
must be installed by a qualied
person. Examples of a qualied
person include gas technicians,
authorized gas company personnel,
and authorized service technicians.
Failure to properly vent the water
heater can result in severe injury
or death from carbon monoxide
poisoning.
The vent system must be installed
according to local and state codes, or
in the absence of local or state codes,
the “Naonal Fuel Gas Code”, ANSI
Z223.1 (NFPA 54)-current edion. Do
not common vent this water heater
with any power vented appliance. Do
not use a vent damper anywhere in
the vent system of this water heater.
GETTING STARTED
GETTING STARTED
background
Residenal Gas Water Heater Use and Care Guide • 11
GETTING STARTED
To reduce the risk of carbon monoxide
poisoning, install a fuel gas and
carbon monoxide detector. Install and
maintain the detector in accordance
with the manufacturers instrucons
and local codes.
Replacing a Water Heater
Using the Exisng Vent System
Read the “Installing a New Vent
System” secon of this manual
and make sure your vent system
is properly installed. Inspect the
exisng vent system for obstrucons,
corrosion, and proper installaon.
Repair or replace if necessary. The
exisng vent system must be UL
listed Type B double-wall or single-
wall metal vent pipe of either 3 inch
or 4 inch diameter and installed
according to the vent manufacturer’s
instrucons and the terms of its
lisng. Do not use other materials
such as dryer vent hose.
Installing a New Vent System
The vent pipe must meet the
following specicaons:
Type of Material
UL listed Type B double-wall or single-
wall metal vent pipe must be used.
Local codes may be more restricve
and may not allow single-wall vent
pipe. Single-wall vent pipe cannot
be used for water heaters located in
acs and may not pass through ac
spaces, crawl spaces, or any conned
or inaccessible locaon. Single-wall
vent pipe cannot pass through any
interior wall.
Clearance to Combusble Materials
NOTICE: Minimum clearances from
combusble surfaces are stated on
the rang plate adjacent to the gas
control valve/thermostat of the water
heater.
All parts of the vent system must
maintain the following clearances
from any combusble materials:
Single-wall vent pipe must maintain
a 6 inch clearance from combusble
materials. The single-wall vent pipe
cannot pass through any ceiling,
oor, rewall, or re paron.
The clearance from combusble
materials of UL listed Type B dou-
ble-wall vent pipe is specied by the
manufacturer of the vent pipe. UL
listed Type B double-wall vent pipe
may pass through walls or parons
constructed of combusble material
if the minimum clearance specied
by the manufacturer of the vent
pipe is maintained.
Vent Installaon
To improve the ow of exhaust gases,
we recommend that a minimum of
12 inches of vercal vent pipe be
installed on the dra hood prior to
any elbow. A poron of the vent pipe
(up to 75% of the total vercal height)
can be horizontal, but the terminaon
must be vercal. For the horizontal
secon, install without dips or sags
with an upward slope of ¼” per foot.
Install pipe avoiding unnecessary
bends. Pipe joints must be fastened by
sheet metal screws or other approved
means. Support the pipe to maintain
clearances and to avoid separaon
of joints or other damage. Vent pipe
must be accessible for cleaning,
inspecon, and replacement.
Terminaons
If local codes allow, this water heater
may be terminated into an exisng
chimney using the instrucons below.
Otherwise, this water heaters vent
must terminate vercally (sidewall or
other horizontal terminaons are not
allowed).
Chimney Terminaon
Figure 7 - Chimney Terminaon Vent System
NOTICE: Before connecng a vent to
a chimney, make sure the chimney
passageway is clear and free of
obstrucons. The chimney must be
cleaned if previously used for venng
solid fuel appliances or replaces.
Also consult local and state codes for
proper chimney sizing and applicaon
or, in the absence of local and state
codes, the “Naonal Fuel Gas Code”,
ANSI Z223.1 (NFPA 54)-current
edion.
• The vent pipe must be installed
above the extreme boom of the
chimney to prevent potenally
blocking the ue gases.
The vent pipe must be rmly at-
tached and sealed to prevent it from
falling out.
To aid in removing the vent pipe, a
thimble or slip joint may be used.
• The vent pipe must not extend be-
yond the inner edge of the chimney
as it may restrict the space between
it and the opposite wall of the
chimney.
Do not terminate the vent pipe in a
chimney that has not been cered
for this purpose. Some local codes
may prohibit the terminaon of vent
connectors in a masonry chimney.
GETTING STARTED
background
12 • Residenal Gas Water Heater Use and Care Guide
Common (combined) venng is
allowable with vercal Type B vent
systems and lined masonry chimneys
as long as proper dra for the
water heater is established under
all condions of operaon. Do not
common vent this water heater with
any power vented appliance.
Vercal exhaust vents must
terminate with a listed cap or other
roof assembly and be installed
according to their manufacturers
instrucons. An unused chimney ue
or masonry enclosure may be used as
a passageway for the installaon of
vent pipe. Do not common vent this
water heater with any power vented
appliance. The following gures
are examples of vent pipe system
installaons and may or may not be
suitable for your specic applicaon.
Consult the “Naonal Fuel Gas Code”,
ANSI Z223.1 (NFPA 54)-current edion
and local codes.
Figure 8 - Vercal gas vent system with Type B
double-wall vent pipe.
Figure 9 - Venng through a chimney with Type
B double-wall vent pipe.
NOTICE: The gas vent must be
terminated in a vercal posion to
facilitate the removal of exhaust
gases.
Gas Piping
Gas piping must be installed according
to local and state codes or, in the
absence of local and state codes, the
“Naonal Fuel Gas Code”, ANSI Z223.1
(NFPA 54)-current edion.
NOTICE: When installing gas piping,
apply pipe joint compound or thread
sealant tape approved for fuel gases.
Figure 10 - Gas Piping
1. Install a readily accessible manual
shut-o valve in the gas supply
line as recommended by the local
ulity. Know the locaon of this
valve and how to turn o the gas
to this unit.
2. Install a Sediment Trap as shown
in the Gas Piping gure above.
The Sediment Trap must be no
less than three inches long for
the accumulaon of dirt, foreign
material, and water droplets.
3. Install a ground joint union be-
tween the gas control valve and
the manual gas shut-o valve.
This is to allow easy removal of
the gas control valve.
4. Turn the gas supply on and check
for leaks. Use a small, so-bris-
tled brush to apply a hand dish-
washing soap and water mixture
(1 part soap to 15 parts water) or
children’s soap bubbles to all con-
necon points of the gas piping.
Saturate all the connecons and
check for gas leaks (which will
appear as small bubbles). If any
leaks are detected, ghten the
appropriate connecon(s) and
re-check.
Gas Pressure
NOTICE: When tesng gas pipes with
a test pressure of more than ½ psi,
disconnect the gas line at the manual
shut-o valve and cap the gas line.
Do not subject the water heater’s gas
control valve or manual shut-o valve
to more than ½ psi pressure for any
reason. If you are pressure tesng
the gas line with test pressure of ½
psi or less, you may isolate the water
heater from the gas line by closing the
manual shut-o valve.
Solar Installaon
If this water heater is used as a solar
storage heater or as a backup for the
solar water heang system, the water
supply temperatures to the water
heater tank may be in excess of 120°F.
A Thermostac Mixing Valve or other
temperature liming valve must be
installed in the water supply line to
limit the supply temperature to 120°F.
The unit must be set to Standard
Mode (see the “Operang Modes”
secon on page 24).
NOTICE: Solar water heang
systems can oen supply water
with temperatures exceeding 180°F
and may result in water heater
malfuncon.
GETTING STARTED
GETTING STARTED
background
Residenal Gas Water Heater Use and Care Guide • 13
INSTALLATION
Step: 1
Verify that Your
Home is Equipped
and Up-To-Date
for Proper Operaon
Installing a new water heater is the
perfect me to examine your home’s
plumbing system and make sure
the system is up to current code
standards. There have likely been
plumbing code changes since the
old water heater was installed. We
recommend installing the following
accessories and any other needed
changes to bring your home up to the
latest code requirements. Updang
your plumbing system can help extend
the life of your water heater, avoid
damage to your home and property,
and reduce the risk of serious injuries
or death. Inspect your home and
install any devices you need to comply
with current codes and assure that
your new water heater performs at its
best. Check with your local plumbing
ocial for more informaon.
Water Pressure
Most codes allow a maximum
incoming water pressure of 80 psi
(we recommend a working pressure
no higher than 50-60 psi). Check
your home’s water pressure gauge
and adjust if necessary. High water
pressure can damage the water
heater, piping, and other appliances.
HOW: Purchase an inexpensive water
pressure gauge available at your local
plumbing supplier. Connect the water
pressure gauge to an outside faucet
and measure the maximum water
pressure experienced throughout
a 24-hour period (highest water
pressures oen occur at night).
140
20
40
60
80
100
120
160
180
200
psi
AVOID FREEZING
Figure 11 - Use a Water Pressure Gauge to make
sure your home’s water pressure is not too high.
To adjust your home’s water pressure:
Locate your home’s Pressure Reducing
Valve (PRV) on the main incoming
(cold) water supply line and adjust the
water pressure control to between
50 and 60 psi. If your home does not
have a Pressure Reducing Valve, install
a PRV on the home’s main water
supply line and set it to between 50
and 60 psi. Pressure Reducing Valves
are available at your local plumbing
supplier.
BACKGROUND: Over the years,
many ulies have increased water
supply pressures so they can serve
more homes. In some homes today,
pressures can exceed 100 psi. High
water pressures can damage water
heaters, causing premature leaks.
If you have replaced toilet valves,
had a water leak, or had to repair
appliances connected to the plumbing
system, pay parcular aenon to
your home’s water pressure. When
purchasing a PRV, make sure the PRV
has a built-in bypass.
Water Pressure
Increase Caused
by Thermal
Expansion
Verify that you have a properly
sized Thermal Expansion Tank. We
recommend installing an expansion
tank if your home does not have one.
Plumbing codes require a properly
pressurized, properly sized Thermal
Expansion Tank in almost all homes.
Figure 12 - A Thermal Expansion Tank helps
protect the home’s plumbing system from
pressure spikes.
HOW: Connect the Thermal Expansion
Tank (available at your local plumbing
supplier) to the cold water supply
line near the water heater. The
expansion tank contains a bladder and
an air charge. To work properly, the
Thermal Expansion Tank must be sized
according to the water heater’s tank
capacity and pressurized to match
the home’s incoming water pressure.
Refer to the instrucons provided
with the Thermal Expansion Tank for
installaon details.
BACKGROUND: Water expands when
heated, and the increased volume
of water must have a place to go, or
thermal expansion will cause large
increases in water pressure (despite
the use of a Pressure Reducing Valve
in the home’s main water supply
line). The Safe Drinking Water Act of
1974 requires the use of backow
preventers and check valves to restrict
water from your home reentering
the public water system. Backow
preventers are oen installed in water
meters and may not be readily visible.
As a result, most all plumbing systems
today are now “closed,” and almost all
homes now need a Thermal Expansion
Tank.
INSTALLATION
background
14 • Residenal Gas Water Heater Use and Care Guide
A Thermal Expansion Tank is a
praccal and inexpensive way to help
avoid damage to the water heater,
washing machine, dishwasher, ice
maker, and even toilet valves. If
your toilet occasionally runs for no
apparent reason (usually briey at
night), that may be due to thermal
expansion increasing the water
pressure temporarily.
NOTICE: Expansion tanks are pre-
charged with a minimum of 12 psi
air charge. The expansion tank’s air
pressure must be adjusted to match
the inlet pressure of your home but
must not be higher than 80 psi.
Water Pipe and
Tank Leaks
METAL
DRAIN
PAN
AT LEAST 2” GREATER THAN THE
DIAMETER OF THE WATER HEATER.
PIPED TO AN
ADEQUATE DRAIN
6” MAXIMUM
AIR GAP
DISCHARGE PIPE
(DO NOT CAP OR PLUG)
Figure 13 - A metal drain pan piped to an
adequate drain can help protect ooring from
leaks and drips.
Leaks from plumbing pipes or from
the water heater itself can damage
property and could cause a re risk.
Install an automac leak detecon
and shut-o device (available at
your local plumbing supplier). These
devices can detect water leaks and
can shut o the water heaters wa-
ter supply if a leak occurs.
Install a metal drain pan (available at
your local plumbing supplier) under
the water heater to catch conden-
saon or leaks from the piping
connecons or tank. Most codes
require, and we recommend, install-
ing the water heater in a metal drain
pan that is piped to an adequate
drain. The drain pan must be at least
2 inches wider than the diameter of
the water heater. Install the drain
pan so the water level would be
limited to a maximum depth of 1-¾”.
The pan must not restrict air ow to
the burner.
Water Tempera-
ture Regulaon
Install Thermostac Mixing Valves
to regulate the temperature of the
water supplied to each point-of-use
(for example, kitchen sink, bathroom
sink, bath, shower). Install and adjust
the mixing valve according to its
manufacturers instrucons.
WARNING! Even if the water
heater’s thermostat is set to a
relavely low temperature, hot water
can scald. Install Thermostac Mixing
Valves at each point-of-use to reduce
the risk of scalding (see Table 1).
MIX

Figure 14 - Thermostac Mixing Valves installed
at each point-of-use can help avoid scalding.
BACKGROUND: A Thermostac Mixing
Valve, installed at each point-of-use,
mixes hot water from the water
heater with cold water to more
precisely regulate the temperature of
hot water supplied to xtures. If you
are not sure if your plumbing system
is equipped with properly installed
and adjusted Thermostac Mixing
Valves at each point where hot water
is used, contact a qualied person.
Step: 2
Verify that the Locaon
is Appropriate
WARNING! Do not store or use
ammable materials, vapors, or
liquids in the same locaon where
this water heater is installed.
WARNING! To reduce the risk of
carbon monoxide poisoning, install
a fuel gas and carbon monoxide
detector if the water heater is
installed in a bathroom, bedroom,
or any occupied room normally
kept closed. Install and maintain
the detector in accordance with the
manufacturers instrucons and local
codes.
Before installing your water heater,
ensure that it will be located:
• Indoors in an area with adequate air
supply.
• Indoors in an area that will not
freeze.
• As close as possible to a chimney or
vent.
• In a metal drain pan piped to an
adequate oor drain or external to
the building (Figure 13).
In an area suitable for vercal instal-
laon.
• In an area with adequate space
(clearances) for periodic servicing
There must be a minimum of 24
inches of front clearance.
• In an area that allows a minimum
clearance from combusble surfaces
as stated on the rang plate.
On a oor that can support the
weight of a full water heater.
Within 6 feet of a 120VAC outlet.
DO NOT use an extension cord.
INSTALLATION
INSTALLATION
background
Residenal Gas Water Heater Use and Care Guide • 15
INSTALLATION
INSTALLATION
You will also want to follow these
guidelines while considering an
appropriate locaon:
• This water heater is not for use in
manufactured (mobile) homes or
outdoor installaon.
Do not install near air-moving devic-
es such as exhaust fans, venlaon
systems, or clothes dryers.
Do not obtain venlang air for the
furnace/air handler from the same
space as the water heater. Ensure
that any return air ducts near the
water heater are sealed.
• If the water heater is located in an
area subject to lint, dust, or oily
vapors, at least annually check and
clean the air lter. See the Mainte-
nance secon for steps on cleaning
the air lter.
• If the water heater is installed
directly on carpeng, it shall be
installed on a metal or wood panel
extending beyond the full width
and depth of the water heater by at
least 3 inches in any direcon. If the
water heater is installed in an alcove
or closet, the enre oor shall be
covered by the aforestated panel.
• If your area is prone to earthquakes,
use special straps as required by
local building codes.
NOTICE: The state of California
requires bracing, anchoring, or
strapping the water heater to avoid its
moving during an earthquake. Contact
local ulies for code requirements in
your area, visit hp://www.dsa.dgs.
ca.gov, or call 1-916-445-8100 and
request instrucons. Other locaons
may have similar requirements. Check
with your local and state authories.
Do not install in a locaon prone to
physical damage by vehicles, ood-
ing, or other risks.
Vehicle
Stop
Drain
Drain
Pan
Figure 15 - In a garage, install a vehicle stop to
avoid water heater damage.
Avoid locaons such as acs, upper
oors, or where leaks might damage
the structure or furnishings. Due
to the normal corrosive acon of
water, the tank will eventually leak.
To minimize property damage from
leaks, inspect and maintain your
water heater in accordance with this
manual’s instrucons. Install a metal
drain pan under the water heater
piped to an adequate drain. Inspect
the drain pan, pipes, and surround-
ing area regularly and x any leaks
found. Drain pans are available at
your local plumbing supplier. Leaks
are frequently in the plumbing sys-
tem itself and not the water heater.
Step: 3
Removing the Old
Water Heater
1
Read each installaon step
and decide if you have the
necessary skills to install the
water heater. Only proceed if you are
comfortable you can safely perform
the work. If you are not sure, have a
qualied person perform the
installaon.
2
On the old water heater, turn
the control knob on the gas
control valve to the OFF
posion.
Mechanical Valve
P
I
L
O
T
O
N
O
F
F
T
u
r
n
TO LIGHT
/
HOLD
IGNITER
RELEASE
KNO
Electronic Valve
P
I
Press down to turn
Turn to
pilot
SCALDING
RISK
INCREASES
WITH
HOTTER
WATER
HOT
LOW
PILOT
OFF
VERY
HOT
A
B
C
VAC
TO LIGHT PILOT:
PRESS
/
HOLD
KNOBIN
POSITION
PRESS
IGNITER
BUTTON
UNTIL
PILOTLIGHTS
RELEASEKNOB
WHEN
STATUS
LIGHT
BLINKS
STATUS
RED
WHITE
FLAMES
STATUS
1
2
3
4
5
6
7
STATUS
LIGHT
CODE
SCALDING
RISK
INCREASES
WITH
HOTTER
WATER
HOT
LOW
PILOT
OFF
VERY
HOT
A
B
C
VAC
PRESS
PRESS
L
O
W
V
E
R
Y
H
O
T
L
O
T
L
I
G
H
T
I
N
G
A
B
C
I
P
CAUTION:
RISK OF SCALDING
INCREASES WITH
HOTTER WATER
Figure 16 - Turn gas control/temperature knob
OFF.
3
Turn the manual gas valve for
the water heater’s supply line
OFF.
4
Open a hot water faucet and
let the hot water run unl it is
cool.
Figure 17 - Let the hot water run unl it is cool.
WARNING! Be sure the water
runs cool before draining the tank to
reduce the risk of scalding.
5
Connect a garden hose to the
drain valve and place the
other end of the hose in a
drain, outside, or in buckets (sediment
in the boom of the tank may clog the
valve and prevent it from draining. If
you cannot get the tank to drain,
contact a qualied person).
background
16 • Residenal Gas Water Heater Use and Care Guide
6
Turn the cold water supply
valve OFF.
Figure 18 - Cold water supply in OFF posion.
7
Open the drain valve on the
water heater.
Figure 19 - Draining the old water heater.
8
Also open a hot water faucet
to help the water in the tank
drain faster.
Figure 20 - Open hot water to drain tank faster.
9
When the tank is empty,
disconnect the Temperature
& Pressure (T&P) Relief Valve
discharge pipe. You may be able to
reuse the discharge pipe, but do not
reuse the old T&P Relief Valve. A new
T&P Relief Valve comes with your new
water heater.
Figure 21 - Removing the T&P Relief Valve
discharge pipe.
10
Allow the vent pipe and dra
hood to cool. Once cooled,
disconnect the vent pipe
from the dra hood. You may need to
support the vent pipe unl the new
water heater is in place.
Figure 22 - Disconnect the vent pipe from the
dra hood.
11
Disconnect the water pipes.
Many water pipes are
connected by a threaded
union which can be disconnected with
wrenches. If you must cut the water
pipes, cut the pipes close to the water
heater’s inlet and outlet connecons,
leaving the water pipes as long as
possible. If necessary, you can make
them shorter later when you install
the new water heater.
12
Conrm the manual gas valve
for the water heaters supply
line is turned OFF. Disconnect
the gas line from the water heaters
gas control valve and cap it.
13
Remove the old water heater.
Use an appliance dolly or
hand truck to move the water
heater.
WARNING! Use two or more
people to remove or install a water
heater. Failure to do so can result in
back or other injury.
Step: 4
Installing the New
Water Heater
1
Completely read all
instrucons before beginning.
If you are not sure you can
safely complete the installaon, seek
assistance from any of the following
sources:
• Schedule an appointment with
a qualied person to install your
water heater.
• Call our Technical Assistance Hotline
which is listed on the water heaters
warranty sheet.
2
Install a metal drain pan that
is piped to an adequate drain.
METAL
DRAIN
PAN
AT LEAST 2” GREATER THAN THE
DIAMETER OF THE WATER HEATER.
PIPED TO AN
ADEQUATE DRAIN
Figure 23 - Metal drain pan piped to an ade-
quate drain.
INSTALLATION
INSTALLATION
background
Residenal Gas Water Heater Use and Care Guide • 17
INSTALLATION
INSTALLATION
3
Set the water heater in place
taking care not to damage
the drain pan. When installing
directly on carpet, the water heater
must be installed on a wood or metal
base that extends beyond the
dimensions of the water heater (width
and depth) by at least 3 inches in any
direcon. If the water heater is
installed on carpet in an alcove or
closet, the enre oor must be
covered by a wood or metal panel.
NOTICE: Most codes require seng
the water heater in a metal drain pan
piped to an adequate drain. The drain
pan helps avoid property damage
which may occur from condensaon
or leaks in the piping connecons or
tank. The drain pan must be at least
2 inches wider than the diameter of
the water heater. Install the drain
pan so the water level is limited to a
maximum depth of 1-¾”.
4
Verify the water heater is
properly set in place. Check
that:
• There is adequate space to install
the T&P Relief Valve discharge pipe
and that it can be piped to a sep-
arate drain (and not into the drain
pan, unless otherwise allowed by
local and state codes).
• There is adequate access and space
around the water heater for future
maintenance.
The water heater is installed ver-
cally.
Step: 5
Check the Air Filter
This water heater is equipped with a
base-ring air lter. Before proceeding
to the next step, visually check the
ler to ensure it is properly seated
in the base-ring. Do not operate the
water heater without a clean air lter
in place.
Step: 6
Connect the
Temperature and
Pressure (T&P) Relief
Valve/Pipe
Most T&P Relief Valves are pre-
installed at the factory. In some cases,
they are shipped in the carton and
must be installed in the opening
marked “T&P Relief Valve” and
according to local and state codes.
WARNING! To avoid serious injury
or death from explosion, install a
T&P Relief Valve according to the
following instrucons.
Figure 24 - Temperature and Pressure Relief
Valve
If the T&P Relief Valve was not factory
installed, install the new T&P Relief
Valve that came with your water
heater. Do not reuse an old T&P
Relief Valve. Install a T&P Relief Valve
discharge pipe according to local
codes and the following guidelines:
The discharge pipe should be at
least ¾” inside diameter and sloped
for proper drainage. Install it to
allow complete drainage of both the
T&P Relief Valve and the discharge
pipe.
The discharge pipe must not be
smaller than the pipe size of the T&P
Relief Valve.
• The pipe must also be able to with-
stand 210°F without distoron. Use
only copper or CPVC pipe approved
for discharge use. Do not use any
other type of pipe, such as PVC,
iron, exible plasc pipe, or any type
of hose.
Figure 25 - The T&P Relief Valve discharge pipe
must be installed properly and piped to an
adequate drain.
Terminate the discharge pipe a max-
imum of 6 inches above a oor drain
or outside the building. Do not drain
the discharge pipe into the drain
pan; instead pipe it separately to
an adequate drain. In cold climates,
terminate the discharge pipe inside
the building to an adequate drain.
Outside drains could freeze and
obstruct the drain line — protect the
discharge pipe from freezing.
6.00"
MAX
Discharge
Pipe
Drain
Pipe
Figure 26 - Temperature and Pressure Relief
Valve Discharge Pipe
Do not place any valve or other re-
stricon between the tank and T&P
Relief Valve. Do not cap, block, plug,
or insert any valve between the T&P
Relief Valve and the end of the dis-
charge pipe. Do not insert or install
any reducer in the discharge pipe.
background
18 • Residenal Gas Water Heater Use and Care Guide
Step: 7
Install Shut-O and
Thermostac Mixing
Valves
1
Install a manual shut-o valve
(available at your local
plumbing supplier) on the
cold water line that supplies the water
heater. Install the shut-o valve near
the water heater so that it is readily
accessible. Only use valves that are
compable with potable water. Use
only full-ow ball or gate valves.
Other types of valves may cause
excessive restricon to the water ow.
2
Install a Thermostac Mixing
Valve at each point-of-use
(for example, kitchen sink,
bathroom sink, bath, shower) per the
valve manufacturers instrucons.
MIX

Figure 27 - Install Thermostac Mixing Valves at
each point-of-use.
WARNING! Even if the water
heater’s thermostat is set to a
relavely low temperature, hot water
can scald. Install Thermostac Mixing
Valves at each point-of-use to reduce
the risk scalding.
3
For water heaters that are fed
by a solar water heang
system (or any other pre-
heang system), always install a
Thermostac Mixing Valve or other
temperature liming device in the
inlet water supply line to limit water
supply inlet temperature to 120°F.
Solar water heang systems can
supply water with temperatures
exceeding 180°F and may result in
water heater malfuncon.
WARNING! Hot water provided
by solar heang systems can cause
severe burns instantly, resulng in
serious injury or death.
Step: 8
Connect the Water
Supply
Note that all piping and components
connected to the water heater must
be suitable for use with potable water.
1
Determine the type of water
pipes in your home. Most
homes use copper water
pipes (see following page), but some
use CPVC or cross-linked polyethylene
(PEX). Use ngs appropriate for the
type of pipe in your home. Do not use
iron or PVC pipe – they are not
suitable for potable water.
The water inlet and outlet threaded
connecons are steel. When
connecng the unit to piping made of
a dierent material, use of a dielectric
ng or a dielectric union conforming
to ASSE 1079 is recommended to
prevent corrosion and potenal
subsequent water leaks at or near the
connecon. Dielectric ngs may be
required by local plumbing codes.
IMPORTANT! A dielectric waterway
nipple is dierent than a dielectric
nipple and does not perform the same
funcon. A dielectric waterway nipple
will not protect the water heater from
corrosion.
2
Connect the cold water
supply using ¾” Naonal Pipe
Thread (“NPT”) to the cold
water inlet nipple.
NOTICE: Most water heater models
contain energy saving heat traps in
the inlet and outlet connecons. Do
not remove the heat traps.
3
Connect the hot water supply
using ¾” NPT to the hot
water outlet nipple.
4
Install insulaon (or heat
tape) on the water pipes
especially if the indoor
installaon area is subject to freezing
temperatures. Insulang the hot
water pipes can increase energy
eciency.
5
Adjust (or install) the home’s
Pressure Reducing Valve to
50-60 psi and install a
Thermal Expansion Tank.
Figure 28 - A Pressure Reducing Valve is re-
quired if your home’s water pressure is above
80 psi.
Figure 29 - The Thermal Expansion Tank should
be pressurized with air to match the home’s
incoming water pressure.
INSTALLATION
INSTALLATION
background
Residenal Gas Water Heater Use and Care Guide • 19
INSTALLATION
INSTALLATION
IF YOU HAVE COPPER PIPES:
If your home has copper water
pipes, you can solder the water pipe
connecons or use compression
ngs which do not require
soldering. Compression ngs
are easier to install than soldering
pipe. Check with local plumbing
ocials to determine what types of
pipe materials are suitable for your
locaon. Do not use lead-based
solder.
Compression ngs don’t require soldering.
NOTICE: Do not solder pipes while
they are aached to the water
heater. The water heaters inlet
and outlet connecons contain
non-metallic parts which could
be damaged. The proper way to
connect the water heater to copper
water pipes is as follows:
Solder a short length of pipe (about
12 inches) to a threaded adapter
using only 95/5 n-anmony
or equivalent solder. Aach the
threaded adaptors to the water
heater’s connecons (using
thread sealant tape or pipe joint
compound). Connect the home’s
water pipes by soldering, keeping
the connecons at the water heater
cool with wet rags. DO NOT over
apply joint compound.
Step: 9
Verify Connecons and
Completely Fill Tank
To remove air from the tank and allow
the tank to ll completely with water,
follow these steps:
1
Remove the ow restrictor at
the nearest hot water faucet.
This allows debris in the
plumbing system to be washed out of
the pipes.
2
Turn the cold water supply
back on and ll the tank.
Figure 30 - Fully open the cold water supply
valve.
3
Open a hot water faucet and
allow the water to run unl it
ows with a full stream.
4
Let the water run full stream
for three minutes.
5
Close the hot water faucet
and replace the ow
restrictor.
6
Check the inlet and outlet
connecons and water pipes
for leaks. Dry pipe
connecons so that any drips or leaks
will be apparent. Repair any leaks.
Almost all leaks occur at connecons
and are not a tank leak.
Step: 10
Install Dra Hood
1
Install the new dra hood by
aligning the legs and inserng
them into the slots on the
ue dampers ange (see Figure 31).
Do not reuse the dra hood from the
old water heater, but rather use the
new one that came with your new
water heater.
2
Secure the dra hood by
bending the leg ps, but do
not alter the dra hood in
any way.
Draft Hood
Flue Damper
Draft Hood
Leg Tip*
* Twist or bend the leg tips to secure the draft
hood to the flue damper.
* Damper orientation may vary.
Figure 31 - Install the new dra hood.
3
Aach the home’s exisng
vent pipe to the dra hood
outlet using an approved vent
adapter (not supplied). Read the
Venng secon on page 10 of this
manual. Make sure your home’s
venng system complies with the
instrucons in this manual and is in
good condion.
background
Step: 11
Make Gas Connecons
The Gas Water Heater Hook-Up Kit
(available at your local plumbing
supplier) includes a exible gas
connector with compression ngs
to connect the home’s gas line
to the water heaters gas control
valve. Follow the kit’s installaon
instrucons to aach the exible gas
connector.
Figure 32 - Flexible Gas Line Connector
Once you have made the gas
connecons, use a small, so-bristled
brush to apply a hand dishwashing
soap and water mixture or children’s
soap bubbles (1 part soap to 15 parts
water) to all connecon points of the
gas line and exible gas connector (if
used). Make sure to generously coat
all the connecons and check for
gas leaks (which will appear as small
bubbles). If any leaks are detected,
turn the gas supply o, ghten the
leaking connecons and re-check.
Step: 12
Electrical Connecons
Before plugging in the water heater,
always make sure:
The voltage and frequency corre-
spond to that specied on the water
heater.
• The electrical outlet has the proper
overload fuse or breaker protecon.
Water heater to be located within 6
feet of 120VAC outlet.
Unit is to connect to a 120VAC elec-
trical supply outlet (extension cord
is not allowed).
• The water heater and the outlet are
properly grounded.
• Installed in accordance with prevail-
ing provisions of local codes, or in
the absence of such, the Naonal
Electric Code, ANSI/NFPA 70 current
edion.
See Figure 60 on page 36 for Wire
Diagram.
WARNING! Electric Shock Hazard:
Disconnect power before servicing.
Replace all parts and panels before
operang. Failure to do so can result
in death or electric shock.
WARNING! Electric Shock Hazard:
Plug into a grounded 3 prong outlet.
Do not remove ground prong. Do
not use an adapter. Do not use an
extension cord. Failure to follow
these instrucons can result in death,
re, or electrical shock.
20 • Residenal Gas Water Heater Use and Care Guide
INSTALLATION
INSTALLATION
background
Residenal Gas Water Heater Use and Care Guide • 21
INSTALLATION
BEFORE LIGHTING THE WATER
HEATER...
Make sure all checklist items have
been completed.
Water Heater Locaon
Centrally located with the water
piping system. Located as close to
gas piping and vent pipe system or
chimney as possible.
Installaon area free of corrosive
or ammable materials, liquids or
vapors.
Proper clearances from combusble
surfaces maintained and sucient
room to service the water heater.
Not installed directly on a carpeted
oor.
Metal drain pan installed and piped
to an adequate drain.
Water heater not located near an
air moving device (fan, clothes
dryer).
Not in a locaon with large amounts
of lint, dust, etc. (if so, the air lter
or ame arrestor located on the
boom of the water heater will
need to be cleaned more oen).
Located indoors and in a vercal
posion. Protected from freezing
temperatures.
Combuson Air Supply and
Venlaon
Adequate air supply for water
heater and any other nearby gas
appliances. If the water heater is
installed in a closet or other small,
enclosed space or within the living
space of the house, air supply open-
ings needed.
Openings are of sucient size.
Ductwork is the same cross-secon-
al area as openings.
Outside air openings are preferred
and may be required in ghtly built
homes.
Vent Pipe System
Vent system installed according
to local and state codes or, in the
absence of local and state codes,
the “Naonal Fuel Gas Code”, ANSI
Z223.1 (NFPA 54)-current edion.
New dra hood, properly installed.
Vent pipe securely fastened to dra
hood with screws and supported
properly.
Check exisng vent system for rust,
restricons and obstrucons.
Water System Piping
Temperature and Pressure Relief
Valve properly installed with a dis-
charge line run to an adequate drain
and protected from freezing.
Water pipes free of leaks.
Water heater completely lled with
water.
Thermal Expansion Tank installed.
Water Pressure Reducing Valve
installed and properly adjusted to
50-60 psi.
Thermostac Mixing Valves installed
at each point-of-use.
Gas Supply and Piping
Gas type is the same as that listed
on the water heater’s data plate.
Gas line equipped with shut-o
valve, union and sediment trap.
Adequate gas pipe size and ap-
proved gas pipe material.
Approved pipe joint compound or
tape used.
All gas connecons and ngs leak
checked and any leaks corrected.
INSTALLATION
background
22 • Residenal Gas Water Heater Use and Care Guide
Lighng Instrucons
WARNING! Explosion Hazard —
Replace viewport if glass is missing or
damaged. Failure to do so can result
in death, explosion or re.
Read and understand these direcons
thoroughly before aempng to light
or re-light the pilot. Make sure the
viewport is not missing or damaged.
Make sure the tank is completely
lled with water before lighng the
pilot. Check the data plate near the
gas control valve to ensure the correct
gas type. Do not use this water heater
with any gas other than the one listed
on the data plate. If you have any
quesons or doubts, consult your gas
supplier or gas ulity company.
NOTICE: A newly installed water
heater will have air in the gas line. It
may take several lighng aempts to
clear all the air from the gas line and
light the pilot.
Follow these steps to light the pilot:
1
Make sure the manual gas
valve for the water heaters
supply line is ON.
Figure 33 - Manual Gas Valve in ON posion.
2
Plug the water heater into a
grounded 120 VAC outlet.
3
Move the ON/OFF switch on
the gas valve to the ON
posion.
SCALDING
RISK
INCREASES
WITH
HOTTER
WATER
OFF
STATUS
ON
24V
HOT
VERY
HOT
A
B
C
VAC
LOW
Figure 34 - Move switch to ON posion.
4
Turn the gas valve thermostat
seng to the LOW
temperature seng.
The water heater will light
automacally. DO NOT try to light
the pilot by hand.
SCALDING
RISK
INCREASES
WITH
HOTTER
WATER
OFF
STATUS
ON
24V
HOT
VERY
HOT
A
B
C
VAC
LOW
Figure 35 - Set knob to LOW seng.
5
When the pilot is lit, the
status light will blink a
heartbeat (bright, dim, bright,
dim, etc.).
6
Adjust the gas control knob
to the HOT seng. Follow the
procedure below if you
receive a ash code (six ashes
followed by a single ash):
a. Turn the power switch on the gas
valve to the OFF posion.
b. Unplug the water heater from the
wall outlet.
c. Wait 10 minutes.
d. Repeat Steps 1-4.
7
Follow the procedure below
if the Status Light does not
start ashing a “heartbeat
aer three lighng aempts:
a. Turn OFF gas to the water heater
at the manual shut-o valve.
b. Move the gas valve’s ON/OFF
switch to the OFF posion.
c. Refer to “No Hot Water” in the
Troubleshoong secon on page
25.
When a gas water heater is rst lit
and the tank is cold, condensaon
oen forms inside the water heater.
You may hear drips or a sizzling
sound when the water heater is rst
lit or, you may see a small puddle
on the oor. Condensaon is not a
leak and will go away once the tank
reaches normal operang tempera-
ture.
The air lter at the boom of the
water heater must be cleaned from
me to me. See the Maintenance
secon on page 32 for steps on
cleaning the air lter.
Shut Down Instrucons
Move the ON/OFF switch on the gas
control valve/thermostat to the OFF
posion. The status light will stop
blinking and stay on for a short me
aer the water heater is turned o.
Emergency Shut Down
Should overheang occur or the gas
supply fails to shut o, follow these
steps:
a. Turn OFF gas to the water heater
at the manual shut-o valve.
b. Move the gas valve’s ON/OFF
switch to the OFF posion.
c. Turn OFF all electric power to the
water heater (unplug it from the
120 VAC outlet).
OPERATION
OPERATION
background
Residenal Gas Water Heater Use and Care Guide • 23
OPERATION
Check the Vent System
and Air Supply
WARNING! Burn Hazard – DO NOT
touch the vent, doing so can cause
burns.
Once the water heater is lit and the
gas control knob is set to the desired
temperature, the burner will light (if
the tank is cold). Perform an air supply
and vent test to make sure the unit is
venng properly and the air supply is
adequate.
1
The main burner must be on
for this test. With a newly
installed water heater full of
cold water, turning the temperature
control knob to HOT should cause the
main burner to come on. You can view
the burner through the sight glass at
the base of the water heater.
2
Close all windows and doors
and turn on all gas appliances
and air-moving devices in
your home (range hoods, bathroom
exhaust fans, ceiling fans, etc.). Also,
close any replace dampers.
3
Allow the water heaters
main burner to operate for
ve minutes. Pass a newly
exnguished match approximately
one inch from the dra hood’s relief
opening. Smoke from the match
should be steadily drawn into the
opening indicang the water heater is
geng adequate air and the vent
system is working.
Match
Relief
Opening
Draft Hood
Figure 36 - Test the air supply and vent to make
sure the water heater has adequate air and is
venng properly.
4
If the main burner has been
operang for ve minutes but
the match smoke dris
around or is blown away from the
opening:
a. Turn OFF gas to the water heater
at the manual shut-o valve.
b. Move the gas valve’s ON/OFF
switch to the OFF posion.
c. Turn OFF all electric power to the
water heater (unplug it from the
120 VAC outlet).
Inspect the vent system and repair
if necessary. In many cases, failure
to pass the air supply and vent
test indicates the water heater is
not geng enough air or there is
a problem with the vent system. It
may be necessary to increase the air
supply by geng air from outside (see
page 7).
WARNING! Burn Hazard – Do
not touch the vent. Doing so can
cause burns. If the dra hood does
not draw in smoke from a match
aer ve minutes of main burner
operaon, shut o the gas supply,
and do not operate the water heater
unl the vent system and air supply
have been checked by a qualied
person and repaired if necessary.
Connuing to operate the water
heater in this condion could lead to
serious injury or death from carbon
monoxide poisoning.
Temperature Control
System
Adjusng the Temperature
With the installaon steps completed,
you may adjust the water heaters
temperature seng if desired.
1
Set the gas valve to the
desired temperature. The
“HOT” seng sets the water
temperature to approximately 120°F,
reducing the risk of scald injury. You
may wish to set a higher temperature
to provide hot water for automac
dishwashers or laundry machines, to
provide more hot water capacity, and
to reduce bacterial growth. Higher
tank temperatures (140°F) kill bacteria
that cause a condion known as
“smelly water” and can reduce the
levels of bacteria that cause water-
borne diseases.
Water usage paerns, as well as
heat from sources such as solar
collectors and ambient air, can result
in temperatures higher than the
thermostat set-point.
WARNING! Higher temperatures
increase the risk of scalding, but even
at 120°F, hot water can scald. Install
Thermostac Mixing Valve(s) at each
point-of-use to reduce the risk of
scalding.
2
To adjust the water heaters
thermostat:
Turn the gas control knob on the
gas control valve to the right to the
following sengs:
VAC 55°F
“LOW” 91°F
• “HOT 120°F
“A 130°F
“B” 140°F
“C 150°F
“VERY HOT” 155°F
NOTICE: The temperatures above are
approximates. The actual temperature
of the heated water may vary.
HOT
VERY
HOT
A
B
C
VAC
LOW
Figure 37 - Adjusng the gas control knob.
OPERATION
background
24 • Residenal Gas Water Heater Use and Care Guide
3
Wait for the water to heat up.
If you have no hot water aer
two hours, refer to the
Troubleshoong Secon (see page
25).
NOTICE: If the tank is full of cold
water, condensaon may form inside
the water heater. This condensaon
may drop on the burner causing a
sizzling sound. In some cases, you
may see a small puddle on the oor.
Condensaon is normal and should go
away once the tank reaches its normal
operang procedure.
WARNING! If you have increased
the temperature seng and the
Thermostac Mixing Valves are not
set properly (or installed) you could
scald yourself while checking the
temperature.
4
Check water temperature at
several points of use in your
home (for example, bathtub
faucet, shower, or lavatory sink) and
adjust the Thermostac Mixing Valves
as needed. If you are not sure how to
adjust the Thermostac Mixing Valve
sengs, or are not sure if you have
Thermostac Mixing Valves, contact a
qualied person.
Operang Modes
Standard Mode - The controller
adjusts the water heater to maintain
the temperature set by the user.
Vacaon - The Vacaon (VAC) mode
sets the thermostat at approximately
55°F and is recommended when
not using hot water for an extended
period of me. The VAC seng also
reduces energy losses and keeps
the tank from freezing during cold
weather but can cause a Hydrogen gas
build up. See cauon on page 6.
OPERATION
OPERATION
background
Troubleshoong &
Maintenance
If you are not qualied or are not
comfortable performing any of
the troubleshoong, repair or
maintenance procedures that follow,
call our Technical Assistance Hotline
for further assistance, or contact a
qualied person.
No Hot Water
Use the following step-by-step plan
as a guide to help determine why you
have no hot water:
1
Check the Status Light
The Status Light on the gas
control valve ashes once every four
seconds when there are no problems
and there is no call for heat.
SCALDING
RISK
INCREASES
WITH
HOTTER
WATER
OFF
ON
24V
HOT
VERY
HOT
A
B
C
VAC
LOW
STATUS
Figure 38 - Status Light
If the Status Light is ashing once
every four seconds and you have no
hot water, make sure the gas control
knob is set to HOT.
If the Status Light ashes a dierent
paern than is described above, refer
to “Gas Control Valve/Thermostat -
Status Light Codes” starng on page
27.
If the Status Light is not ashing, go to
Step 2.
2
Status Light is Not
Flashing
If the Status Light on the gas valve
does not ash, the system may be
locked out. Refer to “Gas Control
Valve/Thermostat - Status Light
Codes” on page 27. Be sure to read
the notes at the top of the owchart.
Insucient Hot Water
or Slow Hot Water
Recovery
WARNING! Because of the
increased risk from scalding, if you
set the water heaters gas control
knob higher than 120°F, install
Thermostac Mixing Valves at each
point-of-use. Due to the increased
risk of scalding, DO NOT set the
temperature of the Thermostac
Mixing Valves above 120°F.
If the hot water is simply not warm
enough, there are several possible
causes:
Faulty Thermostac Mixing Valve in
a faucet or shower control (check
other faucets in the house for hot
water).
• Water heater’s capacity too small
(or usage too high).
Reversed plumbing connecons or
melted dip tube (usually found soon
aer new installaon).
Plumbing leak.
• Sediment or lime buildup in the
boom of the tank.
Thermostac Mixing Valves. If the
hot water is simply not warm enough,
make sure the faucet you are checking
doesn’t have a defecve Thermostac
Mixing Valve. Many shower controls
now have built-in mixing valves. If
these devices fail, they can reduce
the amount of hot water the shower
or faucet delivers even though there
is plenty of hot water in the tank.
Always check the water temperature
at several faucets to make sure the
problem is not in a faucet or shower
control.
Undersized Water Heater. If your
water heater runs out of hot water
quickly, it may be too small for your
needs. If the water heater is old,
consider replacing it with a larger
model. If the water heater is in good
condion, you may be able to meet
your familys hot water needs with
the exisng water heater by installing
Thermostac Mixing Valves at each
point-of-use and then turning the gas
control knob to a higher seng.
You can also reduce your home’s hot
water needs by washing clothes in
cold water, installing ow restrictors
on shower heads, repairing leaky
faucets, and taking other conservaon
steps.
Reversed Connecons or Melted Dip
Tube. Check the hot and cold water
connecons and make sure your
home’s hot water pipe is connected
to the hot water outlet on the water
heater. Usually, reversed connecons
are found soon aer the installaon
of a new unit. If copper pipes were
soldered while they were aached to
the water heater, the dip tube may
have melted. The dip tube is a long,
plasc tube inside the tank aached
to the cold water inlet. If the dip
tube has melted, it can be replaced
by removing the cold water inlet
connecon, removing the old dip tube
and installing a new one.
Plumbing Leak. Even a small leak
in the hot water side of the home’s
plumbing system can make it appear
that the water heater is producing
lile to no hot water. In this case, the
burner will be on all or almost all the
me, yet you will have very lile hot
water. Locate and repair the leak.
Residenal Gas Water Heater Use and Care Guide • 25
TROUBLESHOOTING
TROUBLESHOOTING
background
Sediment or Lime in Tank. With an
exisng water heater, if you have
some hot water but not as much
as you are used to, there may be a
build up of sediment or lime on the
boom of the tank. Sediment or lime
buildup can reduce the eciency of
your water heater. Heavy deposits
can damage the water heater. See
the Maintenance secon for steps
on draining and ushing the water
heater.
Temperature Too High
Adjust the gas control valve/
thermostat on the water heater
to a lower seng. Install or adjust
Thermostac Mixing Valves at
each point-of-use (see the valve
manufacturers instrucons).
Low Water Pressure
Check both the cold and hot water
at a sink to determine if the lower
pressure is only on the hot water side.
If both hot and cold faucets have low
pressure, call your local water ulity.
If the low pressure is only on the hot
water side, the primary causes are:
• Melted heat traps or dip tube. Sol-
dering copper pipes while they are
connected to the water heater can
melt the heat traps inside the hot
and cold water connecons or the
dip tube (cold water side). Melted
heat traps or a melted dip tube can
restrict the ow of hot water. If that
is the case, replace the heat traps or
dip tube.
Parally closed supply valve. Open
the water heater’s supply valve fully.
Drips from T&P Relief
Valve Discharge Pipe
A small amount of water dripping
from the Temperature and Pressure
(T&P) Relief Valve usually means the
home’s water pressure is too high
and/or you need a Thermal Expansion
Tank. See Step 1 in the Installaon
secon on page 13 of this manual
for more informaon.
A large amount of hot water coming
from the T&P discharge pipe may
be due to the tank overheang. If
the T&P Relief Valve is discharging
large amounts of very hot water, turn
the gas supply valve o and call a
qualied person.
WARNING! Do not cap or plug
the T&P Relief Valve or discharge
pipe, and do not operate the water
heater without a funconing T&P
Relief Valve — this could cause an
explosion.
Water Pressure Too High. High
water pressure can cause the T&P
Relief Valve to drip. Install a Pressure
Reducing Valve (PRV) on the main cold
water supply line. Adjust the PRV to
between 50 and 60 psi.
Thermal Expansion Tank. Install a
Thermal Expansion Tank. If a Thermal
Expansion Tank is already installed
and the T&P Relief Valve discharge
pipe drips, the home’s water pressure
may be too high or the Thermal
Expansion Tank may be defecve.
Refer to the instrucons that came
with the Thermal Expansion Tank for
more informaon.
Debris. In rare cases, debris can sck
inside the T&P Relief Valve prevenng
the valve from seang fully. In that
case, the T&P Relief Valve discharge
pipe will drip. You may be able to
clear debris from the T&P Relief Valve
by manually operang the valve,
allowing small quanes of water to
ush out the debris. Refer to the T&P
Relief Valve Maintenance secon of
this manual.
WARNING! When manually
operang the Temperature Pressure
Relief Valve, make sure that no one
is in front of or around the discharge
outlet. The water may be extremely
hot and could cause severe burns.
Also ensure that the water discharge
will not cause property damage.
If the water pressure is between 50
and 60 psi, a Thermal Expansion Tank
is installed and properly pressurized,
and the valve has been cleared of any
debris, and it sll drips, the valve may
be broken — have a qualied person
replace the T&P Relief Valve.
Water Odor
Harmless bacteria normally present
in tap water can mulply in water
heaters and give o a “roen egg
smell. Although eliminang the
bacteria that causes “smelly water”
is the only sure treatment, in some
cases, the standard anode rod that
came with your water heater can be
replaced with a special zinc anode rod
which may help reduce or eliminate
the odor. Contact a qualied person.
NOTICE: To protect the tank, an anode
rod must be installed in the water
heater at all mes or the warranty is
void.
In cases where the “roen egg” smell
is very strong, you could increase the
tank temperature to 140°F in order
to reduce the bacterial growth in the
tank.
WARNING! Because higher
temperatures increase the risk of
scalding, if you set the thermostat(s)
higher than 120°F, Thermostac
Mixing Valves at each point-of-use
are parcularly important.
26 • Residenal Gas Water Heater Use and Care Guide
TROUBLESHOOTING
TROUBLESHOOTING
background
Residenal Gas Water Heater Use and Care Guide • 27
TROUBLESHOOTING
Status Light and Diagnosc Code Troubleshoong Chart
NOTICE:
These codes apply to the gas control valve/thermostat. The locaon of the gas control valve/thermostat is shown on page 2.
Refer to the following pages for detailed troubleshoong procedures.
EXAMPLE: An “Eight-Four Flash” will show eight flashes, then four flashes, followed by a three second pause.
The pattern will then repeat.
*So Lockout - 20 minute wait before returning to normal operang mode.
LED STATUS OR ERROR CODE INDICATES CORRECTIVE ACTION
Short Flash once every four seconds IDLE (no call for heat, no fault condions)
“Heartbeat”, alternates bright/dim Call for Heat (no fault condions)
One Flash, three second pause Low Flame Signal (control connues to
operate)
1) Turn the power switch on the gas control valve/thermostat to the “OFF” posion and unplug the power
cord from the power outlet.
2) Check the incoming gas line pressure to ensure adequate supply to the water heater. If incoming gas
supply pressure is adequate, proceed to Step 3.
3) Check all wiring connecons and ensure all harness and wire connecons are seated rmly and provide
proper electrical contact. If no connecon problems are found, proceed to Step 4. Firmly seat any loose
connecons found. If any connecons are found to be damaged, consult the replacement parts list for the
appropriate replacement. Aer any connecon problems are xed, restart the water heater by following
the lighng instrucons on page 22. If the problem persists, proceed to Step 4.
4) Check the condion of the base ring lter and ame arrestor. If they are clogged, follow the instrucons
for cleaning on page 35. If parts are not clogged, proceed to Step 5. Aer cleaning, follow the
instrucons for lighng on page 22. If problem persists, proceed to Step 5.
5) Follow the instrucons on page 34 to remove the burner assembly. Once the burner assembly has
been removed, inspect the manifold tube and burner for any obstrucons. If any clogs or obstrucons
are present, clear them. Inspect the pilot assembly’s electrode/ame sense rod for corrosion buildup,
degradaon, or damage. If there is evidence of any damage to the electrode/ame sense rod, replace
the igniter/pilot assembly. Follow the direcons on page 34 to re-install the burner assembly into the
combuson chamber. Follow the instrucons for lighng on page 22. If the problem persists, contact a
qualied service representave.
Two Flash, three second pause End Switch Failed Closed 1) Look at the top of the water heater to see if the damper is open (Figure 31 on page 19). If the damper
is open, ensure there is no obstrucon that would prevent the damper from closing. If there are any
obstrucons, turn the power switch on the gas control valve/thermostat to the “OFF” posion, then
remove the obstrucon. If the damper closes, turn the power switch on the gas control valve/thermostat
to the “ON” posion. If there are no obstrucons present, turn the power switch on the gas control valve/
thermostat to the “OFF” posion. Observe the damper to see if the damper closes. If the damper does
not close, unplug the power cord from the power outlet and proceed to Step 2. If the damper closes, turn
the power switch on the gas control valve/thermostat to the “ON” posion.
2) Check all wiring connecons to ensure all harness and wire connecons are seated rmly and provide
proper electrical contact. If no connecon problems are found, replace the damper. Firmly seat any loose
connecons found. If any connecons are found to be damaged, consult the replacement parts list on
page 37 for the appropriate replacement. Aer any connecon problems are xed, restart the water
heater by following the lighng instrucons on page 22. If the problem persists, replace the damper.
Three Flash, three second pause End Switch Failed Open or TCO (Thermal
Cuto) Limit Lockout
1) Turn the power switch on the gas control valve/thermostat to the “OFF” posion and unplug the power
cord from the power outlet.
2) Aempt to depress the TCO door switch buon (see “Completed Installaon” illustraon on page 2).
If the TCO door switch buon depresses, follow the instrucons for cleaning the lter and ame arrestor
on page 35. Aer cleaning is completed, follow the lighng instrucons on page 22. If the TCO door
switch buon does not depress, proceed to Step 3.
3) Follow the lighng instrucons on page 22. Observe the damper during inial startup. If there is a call
for heat and the damper opens, allow the unit to connue to perform and monitor any change in status.
If there is a call for heat and the damper does not open, proceed to Step 4.
4) Check all wiring connecons and ensure all harness and wire connecons are seated rmly and provide
proper electrical contact. If no connecon problems are found, replace the damper. Firmly seat any loose
connecons found. If any connecons are found to be damaged, consult the replacement parts list on
page 37. Aer any connecon problems are xed, restart the water heater by following the lighng
instrucons on page 22. If the problem persists, replace the damper.
Four Flash, three second pause ECO Limit Lockout Turn the power switch on the gas control valve/thermostat to the “OFF” posion, wait 10-20 seconds, then
turn the power switch on the gas control valve/thermostat to the “ON” posion. If the problem persists,
replace the gas control valve/thermostat (see page 33).
Five Flash, three second pause Flame Out Sequence Turn the power switch on the gas control valve/thermostat to the “OFF” posion. Wait 10 minutes, then
follow the lighng instrucons on page 22. If the problem persists, replace the gas control valve/
thermostat (see page 33).
TROUBLESHOOTING
background
LED STATUS OR ERROR CODE INDICATES CORRECTIVE ACTION
Six-One Flash, three second pause So Lockout* - Retry Limit - Failed TFI (Trial
for Ignion)
1) Turn the power switch on the gas control valve/thermostat to the “OFF” posion. Unplug the water heat-
er from the wall outlet. Plug the power cord back in, then follow the lighng instrucons on page 22.
If that does not work, turn the power switch on the gas control valve/thermostat to the “OFF” posion,
unplug the power cord from the power outlet, then follow the steps below.
2) Check the incoming gas line pressure to ensure adequate supply to the water heater. If incoming gas
supply pressure is adequate, proceed to Step 3.
3) Check all wiring connecons and ensure all harness and wire connecons are seated rmly and provide
proper electrical contact. If no connecon problems are found, proceed to Step 4. Firmly seat any loose
connecons found. If any connecons are found to be damaged, consult the replacement parts list for the
appropriate replacement. Aer any connecon problems are xed, restart the water heater by following
the lighng instrucons on page 22. If the problem persists, proceed to Step 4.
4) Check the condion of the base ring lter and ame arrestor. If they are clogged, follow the instrucons
for cleaning on page 35. If parts are not clogged, proceed to Step 5. Aer cleaning, follow the
instrucons for lighng on page 22. If problem persists, proceed to Step 5.
5) Follow the instrucons on page 34 to remove the burner assembly. Once the burner assembly has
been removed, inspect the manifold tube and burner for any obstrucons. If any clogs or obstrucons
are present, clear them. Inspect the pilot assembly’s electrode/ame sense rod for corrosion buildup,
degradaon, or damage. If there is evidence of any damage to the electrode/ame sense rod, replace
the igniter/pilot assembly. Follow the direcons on page 34 to re-install the burner assembly into the
combuson chamber. Follow the instrucons for lighng on page 22. If the problem persists, contact a
qualied service representave.
Six-Two Flash, three second pause So Lockout* - Recycle Limit - Flame Lost -
END Switch Fails
1) Turn the power switch on the gas control valve/thermostat to the “OFF” posion and unplug the power
cord from the power outlet.
2) Check all wiring connecons to ensure all harness and wire connecons are seated rmly and provide
proper electrical contact. If no connecon problems are found, replace the damper. Firmly seat any loose
connecons found. If any connecons are found to be damaged, consult the replacement parts list on
page 37 for the appropriate replacement. Aer any connecon problems are xed, restart the water
heater by following the lighng instrucons on page 22. If the problem persists, replace the damper.
Six-Three Flash, three second pause So Lockout* - Recycle Limit - Flame Lost 1) Turn the power switch on the gas control valve/thermostat to the “OFF” posion and unplug the power
cord from the power outlet.
2) Check the incoming gas line pressure to ensure adequate supply to the water heater. If incoming gas
supply pressure is adequate, proceed to Step 3.
3) Check all wiring connecons and ensure all harness and wire connecons are seated rmly and provide
proper electrical contact. If no connecon problems are found, proceed to Step 4. Firmly seat any loose
connecons found. If any connecons are found to be damaged, consult the replacement parts list for the
appropriate replacement. Aer any connecon problems are xed, restart the water heater by following
the lighng instrucons on page 22. If the problem persists, proceed to Step 4.
4) Check the condion of the base ring lter and ame arrestor. If they are clogged, follow the instrucons
for cleaning on page 35. If parts are not clogged, proceed to Step 5. Aer cleaning, follow the
instrucons for lighng on page 22. If problem persists, proceed to Step 5.
5) Follow the instrucons on page 34 to remove the burner assembly. Once the burner assembly has
been removed, inspect the manifold tube and burner for any obstrucons. If any clogs or obstrucons
are present, clear them. Inspect the pilot assembly’s electrode/ame sense rod for corrosion buildup,
degradaon, or damage. If there is evidence of any damage to the electrode/ame sense rod, replace
the igniter/pilot assembly. Follow the direcons on page 34 to re-install the burner assembly into the
combuson chamber. Follow the instrucons for lighng on page 22. If the problem persists, contact a
qualied service representave.
Six-Four Flash, three second pause So Lockout* - Flame Out of Sequence
Sensed
Turn the power switch on the gas control valve/thermostat to the “OFF” posion and unplug the power cord
from the power outlet. Wait 10 minutes, then follow the lighng instrucons on page 22. If the problem
persists, replace the gas control valve/thermostat (see page 33).
Seven Flash, three second pause Flammable Vapor Sensor (FVS) Lockout 1) Do not touch any electrical switch, do not use any phone in the building, and do not try to light any
appliance.
2) Smell around the water heater to ensure there are no gas leaks at the gas control valve/thermostat or in
the supply gas line or for any other type of ammable vapors in the area.
3) Carefully inspect the area surrounding the water heater for any substances such as gasoline, paint, paint
thinners, varnish, or cleaners that could emit ammable vapors. Remove anything that can potenally
emit ammable vapors from the area and store it properly in a dierent locaon.
4) Contact a qualied service representave for inspecon and/or replacement of the FV sensor.
Eight-One Flash, three second pause Flammable Vapor Sensor (FVS) Fault
Detected
Turn the power switch on the gas control valve/thermostat to the “OFF” posion, wait 10-20 seconds, then
turn the power switch on the gas control valve/thermostat to the “ON” posion. If the problem persists,
replace the gas control valve/thermostat.
Eight-Two Flash, three second pause Temperature Sensor Fault Detected Turn the power switch on the gas control valve/thermostat to the “OFF” posion, wait 10-20 seconds, then
turn the power switch on the gas control valve/thermostat to the “ON” posion. If the problem persists,
replace the gas control valve/thermostat.
Eight-Three Flash, three second pause Electronic Fault Detected Turn the power switch on the gas control valve/thermostat to the “OFF” posion, wait 10-20 seconds, then
turn the power switch on the gas control valve/thermostat to the “ON” posion. If the problem persists,
replace the gas control valve/thermostat.
Eight-Four Flash, three second pause Gas Control Valve/Thermostat Fault Detected Turn the power switch on the gas control valve/thermostat to the “OFF” posion, wait 10-20 seconds, then
turn the power switch on the gas control valve/thermostat to the “ON” posion. If the problem persists,
replace the gas control valve/thermostat.
28 • Residenal Gas Water Heater Use and Care Guide
TROUBLESHOOTING
TROUBLESHOOTING
background
Residenal Gas Water Heater Use and Care Guide • 29
TROUBLESHOOTING
Sequence of Operaons Chart
Apply Power
to Appliance.
Is Damper
Closed?
Y
Is there a
Call for Heat.
Is Damper
Open?
Will not attempt to light.
2 flash error code.
N
Damper Energizes.
Gas Valve attempts to open damper
for 30 seconds then waits 2 minutes
before attempting to open damper
again. If the damper never proves
open, 3 flash error code.
N
Pilot Valve
Energized
Spark Electrode
is Energized
Main Valve
Energized
Is Main
Flame Sensed?
Is Demand for
Heat Satisfied?
Pilot & Main
Valve De-Energize.
Is Flame
Sensed?
Damper Energizes
and Closes.
Will not open. 8-3 or
8-4 flash error code.
N
N
Will not light. 6-3 flash
error code.
N
Water heater will continue to
operate normally until
demand is satisfied.
N
Wait for flame lost, 5 flash
error code.
Y
Damper closes, displays 6-4
flash error code, and gas
control valve goes into 20
minute lockout.
If flame still sensed after 30
seconds, damper re-opens.
Is
Pilot Flame
Sensed Within
1.5 min. ?
Will not light. 6-1 flash
error code.
N
Will not open. 8-3 or
8-4 flash error code.
Figure 39 - Sequence of Operaons Chart
TROUBLESHOOTING
background
Roune Maintenance
Roune maintenance will help your
water heater last longer and work
beer. If you cannot perform these
roune maintenance tasks yourself,
contact a qualied person.
IMPORTANT! Failure to perform
required or recommended
maintenance as described in the
following secons may void the
warranty.
Water Heater Maintenance
Aer the rst six months, drain and
ush the water heater and inspect the
anode rod. Depending on the hardness
of your water, repeat this process at
least annually, or more frequently if
needed.
Draining and Flushing the
Water Heater
Tap water contains minerals that
can form lime deposits or sediment
in the boom of the tank. The
amount of lime deposits or sediment
depends on the hardness of your tap
water. The rate at which sediment
builds up depends on water quality
and hardness in your area, the
temperature sengs, and other
variables. We recommend draining
and ushing the water heater aer
the rst six months of operaon to
determine the amount of sediment
buildup. Draining sediment extends
the life of the tank and drain valve.
IMPORTANT! Failure to drain and
ush the water heater of sediment
can deteriorate the tank and drain
valve and cause leaks resulng in
property damage.
To Drain and Flush the Tank:
1
Turn the gas control knob on
the gas control valve to the
OFF posion.
SCALDING
RISK
INCREASES
WITH
HOTTER
WATER
OFF
STATUS
ON
24V
HOT
VERY
HOT
A
B
C
VAC
LOW
Figure 40 - Move switch to OFF posion.
2
Turn the manual gas valve for
the water heater’s supply line
OFF.
3
Open a hot water faucet and
let the hot water run unl it
is cool.
Figure 41 - Water Faucet.
WARNING! Be sure the water
runs cool before draining the tank to
reduce the risk of scalding.
4
Connect a garden hose to the
drain valve and place the
other end of the hose in a
drain, outside, or in buckets. Note
that sediment in the boom of the
tank may clog the valve and prevent it
from draining. If you cannot get the
tank to drain, contact a qualied
person.
5
Turn the cold water supply
valve OFF.
6
Open the drain valve on the
water heater.
Figure 42 - Draining the water heater.
7
Open a hot water faucet to
help the water in the tank
drain faster.
NOTICE: DO NOT aempt to light
the water heater unless the tank is
completely full of water. For complete
instrucons on lling the tank, follow
Step 8 on page 18.
8
If a large amount of sediment
was present when the tank
was drained, ush the tank
by opening the cold water supply
valve and leng the water run unl
no more sediment drains from the
tank. Close the drain valve when you
are done.
NOTICE: Inspect the anode rod aer
the rst six months of operaon when
you drain and ush the tank. See the
following secon for instrucons on
how to inspect and replace the anode
rod if necessary.
9
Rell the tank by opening the
cold water supply valve.
Make sure a hot water faucet
is open and the drain valve is closed.
Allow a hot water faucet to run full for
at least three minutes to make sure
the tank has all the air removed and is
completely full of water. Once you are
certain the tank is completely full of
water, close the hot water faucet.
30 • Residenal Gas Water Heater Use and Care Guide
MAINTENANCE
MAINTENANCE
background
Residenal Gas Water Heater Use and Care Guide • 31
MAINTENANCE
10
Put the water heater back
into operaon by following
the lighng instrucons on
page 22. Adjust the gas control
knob to the desired temperature. It
may take an hour or more for the tank
of cold water to heat up.
Replacing the Anode Rod
Anode Rod. The anode rod is a
sacricial metal rod and is the water
heater’s rst line of defense to
prevent corrosion and premature
failure (leaks) in the tank. The anode
rod is a consumable item. Inspect the
anode rod aer the rst six months of
operaon when you drain and ush
the tank. Replace the anode rod if it
is substanally worn out or depleted.
Thereaer, inspect the anode rod
annually or more frequently if
needed. If you use a water soener,
your anode rod will deplete faster
than normal. Inspect the anode rod
more frequently, replacing the anode
rod as needed. Obtain a new anode
rod from your local plumbing supplier
or have a qualied person replace it.
(Anode rods are a consumable item
and are not covered under warranty).
1
Remove and inspect the
anode rode (see Figure 61 on
page 38 to locate the
anode rod). Replace the anode rod if
it is depleted. Turn power OFF. Run
hot water unl it is cool. Turn cold
water supply valve OFF. Open a hot
water faucet to depressurize tank.
Locate and remove the black plasc
cover marked “Anode.” Use a “key
hole” saw or similar tool to remove
the foam insulaon covering the
anode rod. Remove the anode rod by
using an impact wrench rated at 1400
·lb breakaway torque and ed with
a 6 point – 1-¹₁₆” socket turning
counterclockwise. Ensure socket is
seated completely on the anode head
before aempng removal to avoid
stripping the anode head. Inspect the
anode rod and replace if depleted.
2
Apply thread sealant tape or
pipe joint compound and
reinstall the anode rod ghtly
using a 1-¹₁₆” socket wrench with an
extension. It is not necessary to
replace the foam removed to access
the anode. Turn cold water supply
valve ON. When hot water runs full,
close hot water faucet. Check for leaks
and repair if necessary. Turn power
ON.
Figure 43 - Anode rods from new (top) to par-
ally depleted (middle) to fully depleted stage
(boom).
Figure 44 - Combinaon heat trap nipple/anode
rods from new (top) to parally depleted (mid-
dle) to fully depleted stage (boom).
NOTICE: If equipped, the combinaon
heat trap nipple/anode rod (see
Figure 44) will be located at the
hot water outlet side of the unit.
Use a pipe wrench at the nipple to
remove and replace the combinaon
heat trap/nipple anode rod. When
removing or replacing the anode rod,
use cauon and DO NOT damage the
nipple threads. If you can not perform
this task yourself, contact a qualied
person.
Visual Inspecon
On an annual basis, visually inspect
the venng and air supply system,
piping systems, main burner, and pilot
burner, and the air lter.
If you lack the necessary skills
required to properly perform this
visual inspecon, or if the burner
needs to be cleaned, get help from a
qualied person.
Check the water heater for the
following:
Obstrucons, damage, or deterio-
raon in the venng system. Make
sure the venlaon and combuson
air supplies are not obstructed.
Check the air lter for dust or other
debris and clean if needed.
• Buildup of soot and carbon on the
main burner and pilot burner. The
burner may be cleaned with soap
and hot water.
Inspect the burner ames through
the viewport and compare them
to the drawing below. A properly
operang burner should produce a
so blue ame. Blue ps with yellow
inner cones are sasfactory. The ps
of the ame may have a slight yel-
low nt. The ame should not be all
yellow or have a sharp blue-orange
color. Contaminated air may cause
an orange colored ame. Contact a
qualied technician if the ame is
not sasfactory.
Figure 45 - Burner Flames
Leaking or damaged water and gas
piping.
Remove any ammable, corrosive
or combusble materials near the
water heater.
MAINTENANCE
background
32 • Residenal Gas Water Heater Use and Care Guide
T&P Relief Valve Maintenance
Read and follow the operang and
annual maintenance instrucons
provided by the manufacturer of
the T&P Relief Valve (yellow label
aached to T&P Relief Valve). If no
label is aached to the T&P Relief
Valve, follow the instrucons in this
secon.
Minerals in the water can form
deposits that cause the valve to sck
or create blocked passages, making
the T&P Relief Valve inoperave.
Follow these guidelines:
At least annually, inspect the T&P
Relief Valve and discharge pipe for
damage caused by corrosive water
condions and mineral depos-
its. Operate the T&P Relief Valve
manually to ensure the waterways
are clear and the valve mechanism
moves freely (see Figure 46). Before
operang the valve manually, check
that it will discharge in a place for
secure disposal.
Aer manually operang T&P Relief
Valve, remove any water in the drain
pan and wipe away any water from
the heater.
WARNING! Hot water will be
released. Before opening the T&P
Relief Valve manually, check that it
will discharge in a safe place. If water
does not ow freely from the end of
the discharge pipe, turn the power to
the water heater OFF. Call a qualied
person to determine the cause.
Figure 46 - T&P Relief Valve
Note that a dripping T&P Relief Valve
is usually caused by the home’s water
pressure being too high and/or lack of
a Thermal Expansion Tank. If your T&P
Relief Valve drips, see page 26.
NOTICE: Expansion tanks are pre-
charged with a minimum of 12 psi
air charge. The expansion tank’s air
pressure must be adjusted to match
the inlet pressure of your home but
must not be higher than 80 psi.
A T&P Relief Valve that has been
allowed to drip for an appreciable
period of me should be inspected for
mineral buildup.
Inspect and Clean Air Filter
An air lter is installed around the
base of your water heater. At least
annually, inspect the air lter and
check for a buildup of dust or debris.
If it needs to be cleaned, turn o the
water heater and allow it to cool for
ten minutes before cleaning. Vacuum
the lter to remove any dust or
debris. If an oily residue is present on
the lter, wash it in soap, and water,
then dry the lter.
NOTICE: If you are unable to inspect
or clean the lter, follow the “Cleaning
the Combuson and Flame Arrestor
instrucons on page 35.
Air Filter
Figure 47 - Clean air filter periodically.
MAINTENANCE
MAINTENANCE
background
Residenal Gas Water Heater Use and Care Guide • 33
Removing and Replacing the
Gas Control Valve
IMPORTANT: The gas control valve
provided with the water heater is a
standard valve.
Removing the Gas Control Valve:
1
Turn the power switch on the
gas control valve to the OFF
posion.
SCALDING
RISK
INCREASES
WITH
HOTTER
WATER
OFF
STATUS
ON
24V
HOT
VERY
HOT
A
B
C
VAC
LOW
Figure 48 - Move switch to OFF position.
2
Turn the manual gas valve for
the water heater’s supply line
OFF.
Figure 49 - Gas valve in “o” posion.
3
Drain the water heater. Refer
to the “Draining and Flushing
the Water Heater” secon
(see page 30) and follow the
procedure.
4
Disconnect the following
items from the gas control
valve:
A
Igniter Wire
B
Wiring Harness
C
FV Sensor Wires
D
Pilot Tube (7/16” wrench)
E
Manifold Tube (3/4” wrench)
Pilot
Tube
Manifold
Tube
FV Sensor
(from bottom of heater)
E
c
D
B
A
Igniter
Wire
Harness
(from black
box and hole
in jacket)
SCALDING
RISK
INCREASES
WITH
HOTTER
WATER
OFF
STATUS
ON
24V
HOT
VERY
HOT
A
B
C
VAC
LOW
Figure 50 - Gas control valve connecons.
5
Disconnect the ground joint
union in the gas piping.
Disconnect the remaining
pipe from the gas control valve.
Figure 51 - Ground joint union connecon.
6
To remove the gas control
valve, thread a 4” secon of
gas pipe into the inlet and use
it to turn the gas control valve
(counterclockwise.) Do not use pipe
wrench or equivalent to grip body.
Damage may result, causing leaks. Do
not insert any sharp objects into the
inlet or outlet connecons. Damage to
the gas control valve may result.
4”
Gas Pipe
SCALDING
RISK
INCREASES
WITH
HOTTER
WATER
OFF
STATUS
ON
24V
HOT
VERY
HOT
A
B
C
VAC
LOW
Figure 52 - Gas control valve with 4” secon of
threaded gas pipe.
Replacing the Gas Control Valve:
To replace the gas control valve,
reassemble in reverse order. When
replacing the gas control valve, thread
a 4” secon of gas pipe into the inlet
and use it to turn the gas control valve
(clockwise.) DO NOT OVER TIGHTEN,
damage may result.
• Be sure to use approved thread
sealant tape or pipe joint compound
on the gas piping connecons and
ng on the back of the gas control
valve that screws into tank.
• Be sure to remove the pilot ferrule
nut from the new gas control valve/
thermostat.
Turn the gas supply ON and check
for leaks. Test the water heater with
the main burner on by brushing
on an approved noncorrosive leak
detecon soluon. Bubbles forming
indicate a leak. Correct any leak
found.
Figure 53 - Gas valve in “on” posion.
Be sure tank is completely lled with
water before lighng and acvang
the water heater. Follow the “Light-
ing Instrucons” on page 22.
If addional informaon is required,
contact our Technical Assistance
Hotline which is listed on the water
heater’s warranty sheet.
MAINTENANCE
MAINTENANCE
background
Removing and Replacing the
Manifold/Burner Assembly
Removing the Manifold/Burner
Assembly:
1
Turn the power switch on the
gas control valve to the OFF
posion.
SCALDING
RISK
INCREASES
WITH
HOTTER
WATER
OFF
STATUS
ON
24V
HOT
VERY
HOT
A
B
C
VAC
LOW
Figure 54 - Move switch to OFF position.
2
Turn the manual gas valve for
the water heater’s supply line
OFF.
Figure 55 - Gas valve in “o” posion.
3
Remove the outer door.
4
Remove the manifold screws
(1/4” nut driver) securing the
manifold door to the combuson
chamber.
Manifold Screw (2)
Manifold Component Block
Manifold Door
Thermal Switch
Pilot Tube
Manifold Tube
Viewport
Wiring
Harness
Gas Control Valve/
Thermostat
FV Sensor
Figure 56 - Front view of water heater with
outer door removed.
5
Go to the gas control valve/
thermostat and disconnect
the pilot tube (7/16”
wrench), igniter wire, and manifold
tube (3/4” wrench). Disconnect the FV
sensor and wiring harness.
6
Grasp the manifold tube and
push down slightly to free the
manifold and pilot tube.
7
Carefully remove the burner
door assembly from the
burner compartment. To
reinstall it, see “Replacing the
Manifold/Burner Assembly” secon.
NOTICE: Be sure not to damage
internal parts.
Replacing the Manifold/Burner
Assembly:
Explosion Risk
WARNING! Failure to
follow these instrucons
can result in serious injury or death
from explosion, re or carbon
monoxide poisoning.
Tighten the manifold door screws
securely.
Remove any berglass between
gasket and combuson chamber.
Replace viewport if glass is missing
or damaged.
• Replace the manifold component
block if it is missing or removed.
Replace door gasket if it is damaged.
1
Check the door gasket for
damage or embedded debris
prior to installaon.
2
Inspect the viewport for
damage and replace as
required.
3
Insert the burner assembly
into the burner
compartment, making sure
that the burner assembly sits rmly
against the burner bracket and spring
(if equipped) inside the combuson
chamber.
Door Gasket
Flame Arrestor Combustion Chamber
Base-ring
Air Filter
Figure 57 - Installing the burner assembly.
Close-up inside view of
the combustion chamber.
Manifold Tube
Bracket
Tab
Slot
Burner
Figure 58 - Inside the combustion chamber.
4
Inspect the door gasket and
make sure there is no
berglass insulaon between
the gasket and the combuson
chamber.
5
Replace the screws which
secure the burner assembly
to the combuson chamber
and ghten securely. There should be
no space between the gasket part of
the burner door and combuson
chamber.
34 • Residenal Gas Water Heater Use and Care Guide
MAINTENANCE
MAINTENANCE
background
WARNING! DO NOT operate the
water heater if the door gasket does
not create a seal between the burner
door and the combuson chamber.
6
Reconnect the manifold
tubing (3/4” wrench), pilot
tubing (7/16” wrench) to the
gas control valve/thermostat. Also
reconnect the FV sensor wires, wiring
harness, and igniter wire (see Figure
50 for the correct posion of each
connecon). Do not cross-thread or
apply any thread sealant to the
ngs.
7
Follow the “Lighng
Instrucons” found on page
22.
8
Check for leaks with the main
burner on by brushing on an
approved noncorrosive leak
detecon soluon. Bubbles forming
indicate a leak. Correct any leak
found.
IMPORTANT: All leaks must be xed
immediately.
9
Replace the outer door.
Cleaning the Combuson
Chamber and Flame-arrestor
See also “Inspect and Clean the Air
Filter” on page 32.
1
Follow the steps in
“Removing the Manifold/
Burner Assembly” on page
34.
2
Use a vacuum cleaner/shop
vac to remove all loose debris
in the combuson chamber.
Use compressed air to clear any dust
or debris that may have accumulated
in the ame-arrestor.
Door Gasket
Flame Arrestor Combustion Chamber
Base-ring
Air Filter
Figure 59 - Installing the burner assembly.
3
Follow the steps in “Replacing
the Manifold/Burner
Assembly” on page 34.
Residenal Gas Water Heater Use and Care Guide • 35
MAINTENANCE
MAINTENANCE
background
Wiring Diagram
You must provide all wiring of the proper size outside of the water heater. You must obey local
codes and electric
utility requirements when you install this wiring.
This appliance must be electrically grounded in accordance with local codes or, in the absence of
local
codes, with the
National Electrical Code ANSI/NFPA No 70 (current edition) and/or THE CSA C22.1 ELECTRICAL CODE.(CURRENT EDITION)
Note: If any of the original wire as supplied with the appliance must be replaced, it
must be replaced with 105
°
C wire or its equivalent.
Caution: Label all wires prior to disconnection when servicing controls. Wiring errors can cause improper and dangerous operation.
FLAME SENSOR\IGNITER
GAS CONTROL VALVE\THERMOSTAT
4 3 2 1
3 2 1
6 5 4
FV SENSOR
TEMPERATURE
CUT-OFF SWITCH
FLUE DAMPER
TRANSFORMER
1 2 3
4 5 6
BL
RD
YL
YL
BN - 24VAC
V - 24VAC
BK - 120VAC
WH - 120VAC
GR
BK - 24VAC (HOT)
WH - 24VAC (NEUTRAL)
BL
RD
BL
RD
YL
YL
BK - 24VAC (HOT)
WH - 24VAC (NEUTRAL)
YL - 24VAC
YL - 24VAC
END SWITCH
DAMPER
TRANSFORMER
YL 24 VAC
GAS CONTROL VALVE/
THERMOSTAT
FV SENSOR
IGNITER/FLAME
SENSOR
BK - 120VAC
W - 120VAC
YL 24 VAC
BK 24 VAC (H)
WH 24 VAC (N)
TEMPERATURE CUT-OFF
SWITCH
YL
YL
ON/OFF SWITCH
BN 24 VAC
V 24 VAC
Figure 60 - Wiring Diagram
36 • Residenal Gas Water Heater Use and Care Guide
MAINTENANCE
MAINTENANCE
background
Residenal Gas Water Heater Use and Care Guide • 37
REPAIR PARTS
REPAIR PARTS
Replacement parts may be ordered through your plumber,
local distributor, home improvement center, or by calling our
Technical Assistance Hotline which is listed on your warranty.
When ordering parts, always give the following informaon:
1. Model, serial, and product number
2. Item number
3. Parts Descripon
Repair Parts List
Item
No.
Parts Descripon
1* Dra Hood
2* Flue Damper
3* Flue Bae
4* Heat Trap (Cold) - Some Models
5* Heat Trap (Hot) - Some Models
6* Cold Water Dip Tube
7* Anode Rod
8* Temperature & Pressure Relief Valve
9* Drain Valve
10* Gas Control Valve
11* Outer Door
12A** STP (Spark To Pilot) Pilot Assembly Kit (Natural Gas)
12B** STP (Spark To Pilot) Pilot Assembly Kit (L.P. Gas)
13A** Burner (Natural Gas/Low NOx)
13B** Burner (L.P. Gas)
14A** Burner Assembly (Natural Gas)
14B** Burner Assembly (L.P. Gas Burner)
15** Manifold Component Block
16** Manifold Door Gasket
17** Viewport Assembly
18* Transformer Assembly Kit
19*** FV Sensor Kit
20*** FV Sensor Kit With Bracket
21*** FV Wire Harness
22*** Main Wire Harness
*
**
***
Pictured on page 38.
Pictured on page 39.
Items not shown.
Legend
Special anode rod (see Anode Rod/Water Odor secon)
Temperature and Pressure Relief Valve is required, but may not be
factory installed
Unique: FVIR System parts
background
38 • Residenal Gas Water Heater Use and Care Guide
Repair Parts Diagram (Water Heater Assembly)
1
2
3
4
8
5
10
11
9
7
6
13
12
14
18
Figure 61 - Repair Parts Diagram (Water Heater Assembly)
REPAIR PARTS
REPAIR PARTS
background
Residenal Gas Water Heater Use and Care Guide • 39
REPAIR PARTS
Repair Parts Diagram (Burner Assembly, NG/LP)
Item 12A: Pilot/Igniter - Flame Sensor assembly kit, which contains the pilot, igniter-ame sensor, and retainer clip (Natural Gas)
Item 12B: Pilot/Igniter - Flame Sensor assembly kit, which contains the pilot, igniter-ame sensor, and retainer clip (L.P. Gas)
Item 13A: Burner (Natural Gas/Low Nox)
Item 13B: Burner (L.P. Gas)
Item 14A: Burner assembly which contains the manifold tube, gasket, door, pilot/igniter-ame sensor assembly, manifold component block with retainer
clip, thermal switch, and pilot tube (Natural Gas/Low Nox)
Item 14B: Burner assembly which contains the manifold tube, gasket, door, pilot/igniter-ame sensor assembly, manifold component block with retainer
clip, thermal switch, and pilot tube (L.P. Gas)
Item 15: Contains manifold component block and retainer clip
Item 16: Contains manifold door gasket
Item 17: Contains viewport
Item #13A
Item #13B
L.P. BURNER
Item #12A
Item #12B
Item #14A
Item #14B
Figure 62 - Repair Parts Diagram (Burner Assembly, NG/LP)
REPAIR PARTS
background
Copyright © 2025, A.O. Smith. All Rights Reserved
Limited Warranty provided by Manufacturer.

Specifications

AO Smith GCF-50 101 Questions and Answers