AO Smith GDV-40L 301 ProLine® 40-Gallon Direct Vent User Manual

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

Residenal Direct Vented Gas Water Heater

with the Flammable Vapor Ignion Resistant Safety System

Not for use in Manufactured (Mobile) Homes

100381379_2000830658

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 neighbor’s phone. Follow the

gas supplier’s 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.

July, 2024

Table of Contents

Important Safety Informaon .................................................. 3

Geng Started ........................................................................ 7

Installaon ............................................................................. 15

Operaon .............................................................................. 23

Troubleshoong .................................................................... 25

Maintenance ......................................................................... 29

Repair Parts ........................................................................... 33

Notes .................................................................................. 35

LOW LEAD

CONTENT

2 • Residenal Gas Water Heater Use and Care Guide

COMPLETED INSTALLATION (TYPICAL)

Vent Termination Hood

Trim Plate

Inlet Water

Shut-off Valve

Thermal

Expansion Tank

Temperature and Pressure

Relief Valve

Combo Heating System

Supply Outlet (Optional)

Discharge Pipe

Combo Heating System

Supply Return Inlet (Optional)

Floor Drain

Drain Pan

Manual Gas

Shut-off

Drip Leg

Gas Control Valve/

Thermostat

Hot Outlet

Cold Inlet

Vent Pipe

Drain Valve

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:

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 heater’s 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-

ufacturer’s 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.

Even if you set the water heater’s 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

SAFETY

IMPORTANT SAFETY INFORMATION

Residenal Gas Water Heater Use and Care Guide • 5

IMPORTANT SAFETY INFORMATION

SAFETY

water heater’s temperature seng.

• 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 heater’s 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

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.

Installaon Accessories

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

Residenal Gas Water Heater Use and Care Guide • 7

GETTING STARTED

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.

This water heater is a direct

vented water heater which

takes its combuson air from

the outside of the structure and

exhausts all products of combuson

to the outside of the structure.

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.

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.

Combuson and

Venlaon Air Supply

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:

For safe operaon an adequate supply

of fresh, uncontaminated air must be

provided for combuson.

This gas-red water heater is a direct

vent model. It connects directly to

the outside of the building through

the vent terminaon hood. The hood

operates as both the combuson air

intake and the heater exhaust port

(see Figure 4).

All combuson air is obtained from

outside the building through this

hood. Ensure the area around the

terminaon hood is always kept clear

and that the air supply is not exposed

to contaminaon or ammable

vapors.

Be sure the vent piping is properly

connected to prevent escape of

dangerous ue gases which could

cause deadly asphyxiaon.

Obstrucons and deteriorated vent

systems may present serious health

risk or asphyxiaon.

8 • Residenal Gas Water Heater Use and Care Guide

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 gas appliance. Do not use

a vent damper anywhere in the vent

system of this water heater.

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 manufacturer’s instrucons

and local codes.

Installing a New Vent System

This direct vent water heater uses a

sealed venng system to supply fresh

combuson air to the heater and to

exhaust the products of combuson

(ue gases) to the outdoors The

venng is a “pipe in a pipe” system.

The inner (3”) piping carries out the

exhaust ue gases while the outer

(6”) piping carries in fresh combuson

air. The corrugated end of the vent

piping connects to the top of the

water heater and the opposite end

connects to the vent terminaon

hood which will be mounted on the

exterior wall (see Figure 4 on the

follow page). Figure 4 shows the hot

exhaust gas exit and the locaon of

the combuson air intake. Figure

7 through Figure 13 show how to

assemble and connect the venng

system.

Figure 14 through Figure 18 show

various installaon opons.

Vent Terminal Clearances

The vent system must terminate so

that proper clearances are maintained

as cited in local codes or the current

edion of the “Naonal Fuel Gas

Code”, ANSI Z223.1/NFPA 54 as

follows:

GETTING STARTED

**Minimum 12 in.

Minimum 12 in.

above grade or

anticipated snow

level

Minimum 12 in.

under veranda, porch,

deck or balcony

(see footnote 1)

Minimum

3 ft.

above if within

10 ft.

horizontally to

a mechanical air

supply inlet

Minimum 9 in. to a non mechanical air supply inlet

into building or combustion air inlet to another appliance

Minimum 12 in.

from soffit

*Minimum 9 in. to

a window or door

that may be opened

**Minimum

18 in.

from outside

corner

1. Permitted only if veranda, porch, deck or balcony is fully opened on a minimum of two sides beneath the floor.

2. A vent shall not terminate above a sidewalk or paved driveway that is located between two single family dwellings and serves both dwellings.

AREA WHERE TERMINAL IS NOT PERMITTED

VENT TERMINAL AIR SUPPLY INLET

Minimum

3 ft.

clearance to a

service regulator

vent outlet

** Or as required by local authorities.

Figure 3 - Proper Clearances for Vent Hood Terminaons

Residenal Gas Water Heater Use and Care Guide • 9

GETTING STARTED

DV Terminaon Hood

When the heater is in operaon, the

vent terminaon hood will be hot (see

Figure 4).

Be sure venng is properly connected

to prevent escape of dangerous

ue gases which could cause deadly

asphyxiaon.

HOT

EXHAUST

GAS OUT

FRESH

COMBUSTION

AIR IN

SCREW

Figure 4 - Vent Terminaon Hood

DV Terminaon Safety Cover

A Safety cover (see Figure 5) is

available to prevent accidental contact

with the vent terminal. Contact your

Customer Service Department for

ordering informaon.

Figure 5 - Safety Cover

Alternavely, a wire mesh or louvered

fencing guard can be built around the

terminaon as shown in Figure 6.

NOT TO BE USED AS

A STORAGE AREA

Figure 6 - Fencing Guard/Safety Cover

Vent Connecon

Aer the locaon for the vent

terminal has been selected as outlined

in Figure 3 and Figure 19, use the

following illustraons for installaon:

Locang Clearance Hole for Vent

Cut a clearance hole, approximately

7”in diameter, through the exterior

wall for the vent assembly. The

recommended height is 64” for 40

gallon models, 73” for 50 gallon

models and 74” for 50 gallon Hi-Input

models, as measured from the hole

center to boom of water heater.

Where the wall is combusble and

the wall thickness is over 14”, a 1”

clearance to combusble surfaces

around the vent terminal is needed.

The rst 14” is zero clearance (see

Figure 9 on page 10).

Standard Vent Arrangement

• If the horizontal length of the vent-

ing is less than 30” the restrictor

plate must be installed (see Figure

10, Figure 16 through Figure 18).

• Do not use the restrictor plate in an

oset installaon (see Figure 14).

• Do not use the restrictor plate if the

horizontal length of the venng is

greater than 30”.

NOTICE: The length of “unstretched”

corrugated tube could cause the

length of the vent run to exceed the

minimum. In this case cut o a piece

of the corrugated tube to achieve the

17” minimum vent length.

10 • Residenal Gas Water Heater Use and Care Guide

Vent Assembly

The vent piping and the vent

terminaon hood are to be connected

as shown in Figure 8. Maintain vent

clearances to combusbles as shown

in Figure 9.

Depending on your access to where

the vent terminaon passes through

the wall, you may wish to connect

the piping and vent terminaon

hood together rst. Inside the vent

piping there are springs that hold

the two corrugated pipes in posion.

When the pipes are stretched to

the required length, the springs will

remain properly spaced.

To connect the vent piping to the vent

terminaon hood, rst slide the inner

(3”) corrugated pipe over the inner

vent terminaon pipe. Connue this

acon unl the locking clip on the

corrugated pipe snaps into posion

in the corresponding groove (see

Figure 7). Secure corrugated pipe with

screw (supplied) inserted through

hole opposite the locking clip.

Repeat this process with the outer

(6”) corrugated pipe and lock it into

posion on the outer pipe on the vent

terminaon (see Figure 7). Secure

corrugated pipe with screw (supplied)

inserted through hole opposite the

locking clip.

NOTICE: To reduce the fricon

between the corrugated pipe and

the O-rings, it is recommended to

dampen the O-rings with water.

Outer

Corrugated

Pipe

Locking

Clip

Inner Vent Termination Pipe

Outer Vent

Termination Pipe

Inner

Corrugated Pipe

Locking Clip

Groove

O-Ring

Figure 7 - Vent Piping

The completed connecon is shown in

Figure 8.

Screw

Figure 8 - Completed Vent Connecon

Securing Vent Terminaon

Assembly to the Exterior Wall

Some models are supplied with trim

plates which may be used to cover

the holes in the wall (see “Completed

Installaon” on page 2 and Figure 9).

Slide one trim plate (if supplied) over

the outer corrugated tube, then insert

the outer corrugated tube through

the clearance hole from exterior wall.

Secure the trim plate to the exterior

wall, then secure the vent terminal to

the exterior wall with 4 screw anchors

(included) appropriate for the type of

wall construcon. Caulk the juncon

of the vent terminal base plate and the

exterior wall with exterior type sealant

(not included). Slide the trim plate

(inside) over the outer corrugated tube

and fasten the trim plate to the interior

wall. Caulk the juncon of the outer

corrugated tube and the trim plate

(inside) with suitable sealant. The vent

terminaon hood aaches to the vent

piping as shown in Figure 8.

Spring

Trim Plate

(Inside)

Apply

Sealant

Cutaway to

Show Spring

Placement

Apply

Sealant

Trim Plate

(Outside)

1”

Clearance

14” Zero

Clearance

Figure 9 - Trim Plate Install

Vent Restrictor Plate

The vent restrictor plate (see Figure 10)

is required for short horizontal runs on

low vent installaons (Figure 16) and

high vent installaons (Figure 18).

For short horizontal vent runs (see

Figure 17) place the restrictor plate

over the ue tube reducer before

connecng the inner corrugated tube

to the ue tube reducer. DO NOT use

the restrictor plate if the horizontal run

is greater than 30”.

For high vercal runs use the restrictor

plate only when the vercal run of the

venng above the heater is greater

than 48” (see Figure 18).

Flue Tube

Reducer

Upper Air

Inlet Box

Restrictor

Plate

Figure 10 - Restrictor Plate

GETTING STARTED

Residenal Gas Water Heater Use and Care Guide • 11

GETTING STARTED

Uncompressing the Corrugated

Tubing

• Pull the inner corrugated tube

towards the water heater and leave

some length over the water heater’s

center for bending (see Figure 11).

• Pull the outer corrugated tube

toward the water heater and leave it

2” shorter than the inner corrugated

tube.

• Make sure there are two springs

evenly spaced at the bend in the

tube.

• Use metal hangers spaced a maxi-

mum of 36” apart to keep venng

level or with a slope upward from the

heater to terminal. It is recommend-

ed to add vibraon isolaon between

the venng and hangers to prevent

vibraon and noise from spreading to

the rest of the building.

Flue Tube

Reducer

Inner

Corrugated

Pipe

Apply

Silicone

Flue Tube

Reducer

Restrictor

Plate

Figure 11 - Uncompressing the Corrugated

Tubing

Vent Connecon to the Water

Heater

Bend both the corrugated pipes

toward the ue connecon on the

water heater. Pull and connect the

inner corrugated pipe to the water

heater’s ue tube reducer with hi-

temp red silicone (included) and gear

clamp. Make sure this connecon is

ght and leak proof (see Figure 12).

*The sealant between the inner

corrugated pipe and water heater’s

ue tube reducer must be hi-temp red

silicone or other material suitable for

600°F connuous service.

NOTICE: If you are using the vent

restrictor plate, the inner vent pipe is

to go over the side legs and down the

stops.

Smooth

Easy Curve

Restrictor

Plate Stop

Cutaway to

Show Details

Gear Clamp

Figure 12 - Vent Connecon to the Water

Heater

Apply hi-temp red silicone (included)

around the collar on air manifold box.

Pull the outer corrugated pipe all the

way on to collar and secure with the

gear clamp. Pull the free end of the

corrugated pipe past the gear clamp

and secure with one sheet metal

screw (see Figure 13).

Smooth

Easy Curve

Apply silicone

to Airbox before

attaching pipe

Secure with

a sheet metal

screw

Gear Clamp

Figure 13 - Apply Silicone to the Venng

Oset Vent Arrangement

Where a straight vent arrangement is

impossible, a horizontal 90° maximum

bend can be made. Use the water

heater casing outer diameter as a

template to form the corrugated tube.

Smooth

Easy Curve

90°

Maximum

Bend

Figure 14 - Venng Alignment (Top View)

NOTICE: To ensure good exhaust gas

ow, bend vent piping using a smooth,

easy curve as shown in Figure 12

through Figure 14. Do not use reverse

or compound curves as shown in

Figure 15.

Figure 15 - Bad Venng Conguraons

GETTING STARTED

12 • Residenal Gas Water Heater Use and Care Guide

Vent Dimensions

Use Table 2 with Figures 16-18.

Table: 2

DIM. 4038 5040 5047

A 80” MAX.

B 9” MIN.

(RECOMMEND)

63.63” 73.00” 74.00”

(MINIMUM)

60.75 69.50 70.50”

D 14.25” MIN.

NOTICE: Dimension “C” is the height above

to oor to the center of the terminaon hole

through the exterior wall.

NOTES: (applies to Figure 16 through

Figure 18)

1. In any installaon the total of

dimension “A” plus dimension “B”

must not exceed 89”.

2. This heater can be installed with

0” clearance to a wall.

3. Minimum vent pipe clearance to

combusbles is 1” (see Figure 9).

4. Minimum distance from center of

heater to wall is 14.25”.

5. Dimension “A” includes wall

thickness.

6. Hole diameter in wall is 7”.

7. Venng must slope up away from

the heater a minimum of 0.25”

per foot of length to prevent

condensaon from collecng and

to provide sucient dra.

8. Distance above horizontal at full

extension is 2”.

9. Use support stays to hold the

venng to avoid sags or valleys.

Above

anticipated

snow level

or 12” above

grade.

Low Vent Installation

Figure 16 - Low Venng Installaon

Above

anticipated

snow level

or 12” above

grade.

Minimum Vent Installation

9”

Figure 17 - Minimum Venng Terminaon

12” Min.

Below

Soffit

72”

Max.

High Vent Installation

17”

Min.

1 5

Figure 18 - High Venng Terminaon

GETTING STARTED

Residenal Gas Water Heater Use and Care Guide • 13

GETTING STARTED

Conned Space

Installaons

This water heater connects to the vent

terminaon hood using the sealed air

intake and exhaust piping.

During operaon this piping

can become hot, especially in

areas experiencing high ambient

temperatures.

When installed in a conned space

such as a closet, it is recommended

that the conned space be venlated

to minimize the buildup of heat

around the water heater. Figure 19

and Figure 20 show examples of

venlang a conned space.

Clearances to

Combusbles

Minimum clearances between water

heater and combusbles is 0” at the

sides and rear, 5-1/2” from the front

and 12” from the top (see Figure 19).

TOP VIEW

OF CLOSET

WITHOUT DOOR

TOP VIEW OF

CLOSET WITH

DOOR

0” MIN.

0”

MIN.

5.5” MIN.

0”

MIN.

Figure 19 - Conned Space Clearances

ROOM

AIR FLOW

ROOM AIR

FLOW

FRONT VIEW

OF DOOR

VENTILATION

AIR

OPENING

Figure 20 - Conned Space Venlaon

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.

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 below.

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.

Figure 21 - Gas Piping

4. Turn the gas supply on and check

for leaks. Use a small, so-bristled

brush to apply a hand dishwash-

ing 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.

High Altude

Installaons

WARNING! High altude orice

must be installed for operaon above

7,700 feet.

Installaons above 7,700’ require

replacement of the burner orice in

accordance with the current edion

of the “Naonal Fuel Gas Code”

(ANSI Z223.1/NFPA 54). Failure to

replace the orice could result in

improper and inecient operaon

of the appliance, producing carbon

monoxide gas in excess of safe limits,

which could result in serious personal

injury or death. Contact your gas

supplier for any specic changes

which may be required in your area.

14 • Residenal Gas Water Heater Use and Care Guide

REMOVE

ST BE VERTICAL TO

IR BUBBLES

OUT

COIL

AIR

HANDLER

AIR

HANDLER

SHUT-OFF

VALVE

EXPANSION TANK

VACUUM

RELIEF

VALVE

COLD WATER INLET

FLOW CONTROL

PUMP

SHUT-OFF

CHECK VALVE

†

(1/8” HOLE

DRILLED IN CLAPPER)

VALVE

CHECK

VALVE

†

TEMP/

PRESSURE

RELIEF

VALVE

TEMPERED WATER

TO FIXTURES

(MUST MEET TEMPS LISTED

IN MASS. CODE 248 CMR

†

)

MIXING VALVE

(MUST BE INSTALLED BELOW

TOP OF WATER HEATER

AS PER MANUFACTURER’S

RECOMMENDATIONS)

UNION

HOT

WATER

OUT

MASSACHUSETTS INSTALLATION REQUIREMENTS:

1.) CONNECT ELECTRONICALLY-CONTROLLED TIMER TO AN ALL-BRONZE PUMP. PUMP MUST ACTIVATE EVERY 6 HOURS

FOR 60 SECONDS. TURN PUMP TIMER OFF BEFORE CLOSING PIPING LOOP SHUT-OFF VALVE.

2.) ALL WATER PIPING MUST BE INSTALLED AND INSULATED IN ACCORDANCE WITH MASSACHUSETTS CODE (248 CMR

& 780 CMR).

3.) PIPING LOOP BETWEEN WATER HEATER AND AIR HANDLER MUST BE INSTALLED IN COMPLIANCE WITH 248 CMR.

† REQUIRED FOR MASSACHUSETTS.

‡ PIPING FROM THE TOP OF THE WATER HEATER WITH TEES IS ACCEPTABLE.

WATER HEATER ACCEPTED

BY THE BOARD FOR

INSTALLATION IN

MASSACHUSETTS.

†

TYPICAL MIXING VALVE INSTALLATION

COMBINATION SPACE HEATING / POTABLE WATER HEATING SYSTEM

SEE

NOTE ‡

100’-0” MAXIMUM DISTANCE

FROM WATER HEATER

TO FAN COIL AND BACK

(DEVELOPED LENGTH) NOT

INCLUDING COIL IN HEATING UNIT.

†

Figure 22 - Combuson Space Heang and Potable Water (Typical Installaon)

Space Heang

Some water heater models are

equipped with inlet/outlet side

connecons for use with space

heang applicaons. If this water

heater is to be used to supply both

space heang and domesc potable

(drinking) water, the instrucons

listed below must be followed:

• This water heater is suitable for

combinaon water (potable) heang

and space heang and not suitable

for space heang applicaons only.

The side connecons may not be

used as the primary water inlet and

outlet connecons. If the heater is

to be operated without using the

side connecons, these openings

MUST be closed with the two plugs

supplied with the heater.

• Be sure to follow the manual(s)

shipped with the air handler system.

• This water heater is not to be used

as a replacement for an exisng

boiler installaon.

• Do not use with piping that has

been treated with chromates, boiler

seal or other chemicals and do not

add any chemicals to the water

heang piping.

• If the space heang system requires

water temperatures in excess of

120°F, install a Thermostac Mixing

Valve in the domesc (potable) hot

water supply at each point-of-use to

limit the risk of scald injury. Install

the mixing valve per its manufactur-

er’s instrucons.

• Pumps, valves, piping, and ngs

must be compable with potable

water.

• A properly installed ow control

valve is required to prevent ther-

mosiphoning. Thermosiphoning is

the result of a connuous ow of

water through the air handler circuit

during the o cycle.

• The domesc hot water line from

the water heater should be vercal

past any mixing valve or supply line

to the air handler to remove air bub-

bles from the system. Otherwise,

these bubbles will be trapped in

the air handler heat exchanger coil,

reducing eciency.

• Do not connect the water heater to

any system or components previ-

ously used with non-potable water

heang appliances when used to

supply potable water.

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 Operang Modes

in Operaon 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

Residenal Gas Water Heater Use and Care Guide • 15

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

100

120

160

180

200

psi

AVOID FREEZING

Figure 23 - 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 24 - 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

16 • 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.

✓

Water Pipe and

Tank Leaks

Drain

Drain Pan

Discharge Pipe

Figure 25 - 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 heater’s 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

manufacturer’s 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 26 - 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

manufacturer’s instrucons and local

codes.

Before installing your water heater,

ensure that it will be located:

• Indoors in an area with adequate air

supply.

• In an area that will not freeze.

• As close as possible to the vent

terminaon.

• In a metal drain pan piped to an

adequate oor drain or external to

the building (Figure 25).

• 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 page 13 of this manual

and the “Flammable Vapors” label

on the water heater.

• On a oor that can support the

weight of a full water heater.

INSTALLATION

Residenal Gas Water Heater Use and Care Guide • 17

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 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

Pan

Figure 27 - 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

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.

On the old water heater, turn

the control knob on the gas

control valve to the OFF

posion.

Mechanical Valve

TO LIGHT

HOLD

IGNITER

RELEASE

KNO

Electronic Valve

Press down to turn

Turn to

pilot

SCALDING

RISK

INCREASES

WITH

HOTTER

WATER

HOT

LOW

PILOT

OFF

VERY

HOT

VAC

TO LIGHT PILOT:

PRESS

HOLD

KNOBIN

POSITION

PRESS

IGNITER

BUTTON

UNTIL

PILOTLIGHTS

RELEASEKNOB

WHEN

STATUS

LIGHT

BLINKS

STATUS

RED

WHITE

FLAMES

STATUS

LIGHT

CODE

SCALDING

RISK

INCREASES

WITH

HOTTER

WATER

HOT

LOW

PILOT

OFF

VERY

HOT

VAC

PRESS

CAUTION:

RISK OF SCALDING

INCREASES WITH

HOTTER WATER

Figure 28 - Turn gas control/temperature knob

OFF.

Turn the manual gas valve for

the water heater’s supply line

OFF.

Open a hot water faucet and

let the hot water run unl it is

cool.

Figure 29 - 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.

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).

Turn the cold water supply

valve OFF.

Figure 30 - Cold water supply in OFF posion.

Open the drain valve on the

water heater.

18 • Residenal Gas Water Heater Use and Care Guide

Figure 31 - Draining the old water heater.

Also open a hot water faucet

to help the water in the tank

drain faster.

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 32 - Removing the T&P Relief Valve

discharge pipe.

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 33 - Disconnect the vent pipe from the

dra hood.

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.

Conrm the manual gas valve

for the water heater’s supply

line is turned OFF. Disconnect

the gas line from the water heater’s

gas control valve and cap it.

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

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 heater’s

warranty sheet.

Install a metal drain pan that

is piped to an adequate drain.

Drain

Drain Pan

Discharge Pipe

Figure 34 - Metal drain pan piped to an ade-

quate drain.

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.

INSTALLATION

Residenal Gas Water Heater Use and Care Guide • 19

INSTALLATION

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”.

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

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 codes.

WARNING! To avoid serious injury

or death from explosion, install a

T&P Relief Valve according to the

following instrucons.

Figure 35 - 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 withstand 250°F without

distoron. Use only copper or CPVC

pipe. Do not use any other type of

pipe, such as PVC, iron, exible plas-

c pipe, or any type of hose.

Figure 36 - 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 37 - 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.

Step: 6

Install Shut-O and

Thermostac Mixing

Valves

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.

20 • Residenal Gas Water Heater Use and Care Guide

Install a Thermostac Mixing

Valve at each point-of-use

(for example, kitchen sink,

bathroom sink, bath, shower) per the

valve manufacturer’s instrucons.

MIX



Figure 38 - 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.

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: 7

Connect the Water

Supply

Note that all piping and components

connected to the water heater must

be suitable for use with potable water.

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.

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.

Connect the hot water supply

using ¾” NPT to the hot

water outlet nipple.

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.

Adjust (or install) the home’s

Pressure Reducing Valve to

50-60 psi and install a

Thermal Expansion Tank.

Figure 39 - A Pressure Reducing Valve is re-

quired if your home’s water pressure is above

80 psi.

Figure 40 - The Thermal Expansion Tank should

be pressurized with air to match the home’s

incoming water pressure.

INSTALLATION

Residenal Gas Water Heater Use and Care Guide • 21

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 heater’s 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: 8

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:

Remove the ow restrictor at

the nearest hot water faucet.

This allows debris in the

plumbing system to be washed out of

the pipes.

Turn the cold water supply

back on and ll the tank.

Figure 41 - Fully open the cold water supply

valve.

Open a hot water faucet and

allow the water to run unl it

ows with a full stream.

Let the water run full stream

for three minutes.

Close the hot water faucet

and replace the ow

restrictor.

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: 9

Install New Vent Pipe

Install the new vent pipe on

top of the water heater. Do

not reuse the vent pipe from

the old water heater, but rather use

the new one that came with your new

water heater. Follow “Venng” on

page 8.

Step: 10

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 heater’s gas control

valve. Follow the kit’s installaon

instrucons to aach the exible gas

connector.

Figure 42 - 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.

22 • Residenal Gas Water Heater Use and Care Guide

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 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.

✓ Located indoors and in a vercal

posion. Protected from freezing

temperatures.

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.

✓ Evenly stretched out between water

heater and vent terminaon hood.

✓ Smooth bends with adequate

support to prevent sagging, 0.25”

per foot.

✓ Inside pipe (3”) and outside pipe

(6”) securely fastened to vent termi-

naon hood.

✓ Vent restrictor plate installed on

heater ue outlet as applicable.

✓ Not obstructed in any way.

Vent Terminaon Hood

✓ Securely fastened to exterior wall.

✓ Above ancipated snow level or 12”

above grade.

✓ Proper clearances from windows,

doors, corners, other vent openings

etc..

✓ Area around vent terminaon hood

clear and unobstructed.

✓ No ammable vapor eming prod-

ucts stored nearby.

✓ Safety covers in place (when appli-

cable).

Water System Piping

✓ Temperature and Pressure Relief

Valve properly installed with a

discharge 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.

Residenal Gas Water Heater Use and Care Guide • 23

OPERATION

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:

Make sure the manual gas

valve for the water heater’s

supply line is ON.

Figure 43 - Manual Gas Valve in ON posion.

Turn the gas control knob to

the PILOT posion.

Press the gas control knob in

fully and hold it in. While

holding in the gas control

knob, repeatedly click the igniter

buon (approximately once per

second) for up to 90 seconds or unl

the Status Light starts to ash. You can

tell the pilot is lit when the Status

Light ashes once every three

seconds.

Once the Status Light starts

ashing, release the gas

control knob. Adjust the gas

control knob to the desired

temperature seng.

If the Status Light doesn’t

start ashing aer 90

seconds, release the gas

control knob and wait 10 minutes.

Repeat lighng steps 2

through 5 at least two

addional mes or unl the

Status Light starts ashing once every

three seconds. Wait 10 minutes

between lighng aempts.

A solid Status Light means the

pilot was lit but is now o.

Release the gas control knob

and wait 10 minutes. Once the Status

Light goes out, repeat lighng steps 2

through 5.

If the Status Light doesn’t

start ashing aer three

lighng aempts, turn the

gas control knob to the OFF posion

and refer to the “Troubleshoong - No

Hot Water” secon (see 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 temperature.

Shut Down Instrucons

Turn the gas control/temperature

knob counterclockwise to the “OFF”

seng. The status light will stop

blinking and stay on for a short me

aer the water heater is turned o.

Emergency Shut Down

This water heater is equipped with

an automac gas shut-o system.

This system works when high water

temperatures are present. Turn

“OFF” the enre gas supply to the

water heater. The high temperature

shut-o is built into the gas control

valve. It is non-reseable. If the high

temperature shut-o acvates, the

gas control valve must be replaced.

See “Removing and Replacing the Gas

Control Valve/Thermostat” on page

32, or contact a qualied professional.

Should overheang occur or the gas

supply fail to shut o, turn o the

water heater’s manual gas control

valve and call a qualied person.

Check the Vent System

and Air Supply

WARNING! Burn Hazard. Do not

touch the vent, doing so can cause

burns.

Check for obstrucons and/or

deterioraon of the vent piping, the

intake air and vent terminaons. The

combuson and venlaon air ow

must not be obstructed. Repair and/or

replace immediately as necessary.

NOTICE: Do not reach inside the vent

terminaon while the heater is in

operaon.

Remove any debris that may have

accumulated on the screen in the vent

terminaons.

Check all vent system connecons for

damage or deterioraon which could

cause improper venng or leakage of

combuson products. Repair or reseal

as necessary.

Be sure the vent piping is properly

connected to prevent escape of

dangerous ue gasses which could

cause deadly asphyxiaon.

OPERATION

24 • Residenal Gas Water Heater Use and Care Guide

Obstrucons and deteriorated vent

systems may present serious health

risk or asphyxiaon.

Chemical vapor corrosion of the ue

and vent system may occur if air for

combuson contains certain chemical

vapors. Spray can propellants,

cleaning solvents, refrigerator and air

condioner refrigerants, swimming

pool chemicals, calcium and sodium

chloride, waxes, bleach and process

chemicals are typical compounds

which are potenally corrosive.

If aer inspecon of the vent system

you found soong or deterioraon,

something is wrong. Call the local

gas ulity to correct the problem and

clean or replace the ue and venng

before resuming operaon of the

water heater.

Temperature Control

System

Adjusng the Temperature

With the installaon steps completed,

you may adjust the water heater’s

temperature seng if desired.

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,

ambient air, and the pilot light 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.

To adjust the water heater’s

thermostat:

HOT

LOW

PILOT

OFF

VERY

HOT

VAC

TO LIGHT PILOT:

PRESS

HOLD

KNOB IN

POSITION

PRESS

IGNITER

BUTTON

UNTIL

PILOT LIGHTS

RELEASE KNOB

WHEN

STATUS

LIGHT

BLINKS

Figure 44 - Adjust the gas control knob to “HOT”.

Turn the gas control knob on the

gas control valve to the right to the

following sengs.

• “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.

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.

Operang Modes

Standard Mode - The controller

adjusts the water heater to maintain

the temperature set by the user.

Vacaon - The “LOW” posion sets

the controller at approximately 91°F.

This seng is recommended for mes

when the water heater will not be in

use for an extended period of me.

It eecvely turns the controller

temperature seng down to a

temperature that prevents the water

in the water heater from freezing

while sll conserving energy.

OPERATION

Residenal Gas Water Heater Use and Care Guide • 25

TROUBLESHOOTING

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:

Check the Status Light

The Status Light on the gas

control valve ashes once every three

seconds if the pilot is lit and the gas

control valve has not detected any

problems.

SCALDING

RISK

INCREASES

WITH

HOTTER

WATER

HOT

LOW

PILOT

OFF

VERY

HOT

VAC

TO LIGHT PILOT:

PRESS

HOLD

KNOB IN

POSITION

PRESS

IGNITER

BUTTON

UNTIL

PILOT LIGHTS

RELEASE KNOB

WHEN

STATUS

LIGHT

BLINKS

STATUS

RED

WHITE

FLAMES

STATUS

LIGHT

CODE

Figure 45 - Status Light

Status Light is Not

Flashing

If the Status Light is ashing once

every three seconds and you have no

hot water, make sure the gas control

knob is set to HOT.

If the Status Light ashes more than

once every three seconds, refer to

the Status Light Code Troubleshoong

Chart on page 27.

If the Status Light is not ashing, go to

step 3.

Checking the Pilot Light

Check the spark igniter. Dim the room

lights and look through the viewport

while clicking the igniter buon.

If you don’t see a spark through the

viewport, check to make sure the

igniter wire is rmly inserted into the

white connector.

If you see a spark, make sure the gas

supply valve is turned on, and try

lighng the pilot using the lighng

instrucons on page 23.

If the pilot sll does not light, call a

qualied person.

Insucient Hot Water

or Slow Hot Water

Recovery

WARNING! Because of the

increased risk from scalding, if you

set the water heater’s thermostat(s)

higher than 120°F, Thermostac

Mixing Valves at each point-of-use

are parcularly important.

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 family’s 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.

TROUBLESHOOTING

26 • Residenal Gas Water Heater Use and Care Guide

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.

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

manufacturer’s 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 15 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.

TROUBLESHOOTING

Status Light and Diagnosc Code Troubleshoong Chart

LED STATUS OR ERROR CODE INDICATES CORRECTIVE ACTION

0 FLASHES (LED NOT LIT) Pilot light is not lit or thermopile has not yet

reached normal operang temperature.

Turn Gas Control Valve/Thermostat knob to “OFF”.

Wait 10 minutes, then aempt to relight Pilot by

following the lighng instrucons on the water

heater’s label. Unl the thermopile reaches its

normal operang temperature, the Status Light

will not blink, even if the Pilot is lit. It may take

up to 90 seconds of connuous Pilot operaon

before the thermopile reaches normal operang

temperature and the Status Light starts to blink. If

the Status Light does not blink aer three lighng

aempts, check to make sure unit is geng

gas. Remove the outer door. Press reset buon.

Replace outer door. Turn Gas Control Valve/

Thermostat knob to “OFF”. Wait 10 minutes, then

aempt to light Pilot by following the lighng

instrucons on the water heater’s label. Look

through the view port for the Pilot ame. If Pilot

is not visible, the spark igniter or gas supply to the

Pilot should be checked. If the Pilot is visible and

the Status Light does not blink aer 90 seconds

of connuous Pilot operaon, the Pilot ame may

not be heang the thermopile suciently (weak

Pilot), the thermopile may be defecve, or wiring

connectors may be loose.

RED LIGHT ON (SOLID) Pilot light was recently exnguished and the

thermopile is cooling down.

Turn Gas Control Valve/Thermostat knob to “OFF”.

Wait 10 minutes for the thermopile to cool, then

aempt to relight Pilot by following the lighng

instrucons on the water heater’s label.

NOTE: This gas control valve/thermostat has

built-in circuitry that requires waing 10 minutes

between lighng aempts.

Unl the thermopile reaches its normal operang

temperature, the Status Light will not blink, even

if the Pilot is lit. It may take up to 90 seconds of

connuous Pilot operaon before the thermopile

reaches normal operang temperature and the

Status Light starts to blink.

1 FLASH (EVERY 3 SECONDS) Normal Operaon No correcve acon necessary.

2 FLASHES Pilot is lit but the thermopile is not producing the

required output voltage.

Turn Gas Control Valve/Thermostat knob to “OFF”.

The thermopile is probably defecve, but loose

wiring connecons or a weak Pilot ame can also

cause this symptom.

4 FLASHES The Gas Control Valve’s temperature sensor has

detected that the water temperature was too high.

Once this condion occurs, the Main Burner and

the Pilot Light will be shut o. Since the Pilot light

will be o, should this condion occur, this Flash

Code will only be displayed immediately aer

the Pilot has been relit. Turn Gas Control Valve/

Thermostat knob to “OFF”.

Relight pilot and verify 4 ashes. If 4 ashes are

observed, turn Gas Control Valve/Thermostat knob

to “OFF”. Turn Main Gas Supply “OFF.” Replace the

Gas Control Valve/Thermostat. See “Removing and

Replacing the Gas Control Valve/Thermostat.”

5 FLASHES The temperature sensor (thermistor) is defecve. Turn Gas Control Valve/Thermostat knob to “OFF”.

Replace the temperature sensor (thermistor).

7 FLASHES Gas Control Valve failure. Turn Gas Control Valve/Thermostat knob to “OFF”.

Turn Main Gas Supply “OFF”. Replace the Gas

Control Valve/Thermostat. See “Removing and

Replacing the Gas Control Valve/Thermostat.”

Residenal Gas Water Heater Use and Care Guide • 27

TROUBLESHOOTING

LED STATUS OR ERROR CODE INDICATES CORRECTIVE ACTION

8 FLASHES This condion only appears if the gas control/

temperature knob has been turned o and the

thermopile connued to produce electric power.

This condion can occur if the thermopile does not

cool down as quickly as expected when the unit

is shut o. This condion can also occur if the gas

control/temperature knob has been turned o and

the pilot connues to operate because the pilot

valve is stuck in the open posion.

Make sure that the gas control valve/thermostat

knob is set to “OFF”. Wait one minute. Remove

the outer door. Look through the sight glass for a

pilot ame. If a pilot ame is observed with the

gas control valve/thermostat knob set to the “OFF”

posion, the pilot valve is stuck open. Turn the

main gas supply “OFF”. Replace the gas control

valve/thermostat. For instrucons, see “Removing

and Replacing the Gas Control Valve/ Thermostat.”

If the pilot ame is not observed when the gas

control valve/thermostat knob is set to the “OFF”

posion, wait 10 minutes for the thermopile to

cool, then aempt to relight the pilot by following

the lighng instrucons on the water heater’s

label. If this condion returns, replace the gas

control valve/thermostat. See “Removing And

Replacing The Gas Control Valve/Thermostat” for

instrucons.

28 • Residenal Gas Water Heater Use and Care Guide

TROUBLESHOOTING

Residenal Gas Water Heater Use and Care Guide • 29

MAINTENANCE

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. From me to me, you may

need to replace a heang element or

a thermostat. All three maintenance

tasks are described below.

Draining and Flushing the

Water Heater

Tap water contains minerals that

can form lime deposits on heang

elements 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:

Turn the gas control knob on

the gas control valve to the

OFF posion.

HOT

LOW

PILOT

OFF

VERY

HOT

VAC

TO LIGHT PILOT:

PRESS

HOLD

KNOB IN

POSITION

PRESS

IGNITER

BUTTON

UNTIL

PILOT LIGHTS

RELEASE KNOB

WHEN

STATUS

LIGHT

BLINKS

Figure 46 - Turn gas control/temperature knob

OFF.

Turn the manual gas valve for

the water heater’s supply line

OFF.

Open a hot water faucet and

let the hot water run unl it is

cool.

Figure 47 - Water Faucet.

WARNING! Be sure the water

runs cool before draining the tank to

reduce the risk of scalding.

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.

Turn the cold water supply

valve OFF.

Open the drain valve on the

water heater.

Figure 48 - Draining the water heater.

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 21.

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.

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.

MAINTENANCE

30 • Residenal Gas Water Heater Use and Care Guide

MAINTENANCE

Relight the pilot using the

instrucons on page 23 and

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).

Remove and inspect the

anode rode (see the Repair

Parts illustraon on page 33

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.

Once the anode rod is exposed, use a

1-¹⁄₁₆” socket wrench with an

extension to remove it. Inspect the

anode rod and replace if depleted.

Apply thread sealant tape or pipe joint

compound and reinstall the anode rod

ghtly. 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 49 - Anode rods from new (top) to par-

ally depleted (middle) to fully depleted stage

(boom).

Figure 50 - 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 50) 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.

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.

• 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 op-

era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 51 - Burner Flames

• Aer several minutes, the burner

screen may glow red. If large ames

are observed at any me, shut o

the unit and call a qualied person.

• Leaking or damaged water and gas

piping.

• Remove any ammable, corrosive

or combusble materials near the

water heater.

MAINTENANCE

Residenal Gas Water Heater Use and Care Guide • 31

MAINTENANCE

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 52). 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 52 - 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.

A T&P Relief Valve that has been

allowed to drip for an appreciable

period of me should be inspected for

mineral buildup.

MAINTENANCE

32 • Residenal Gas Water Heater Use and Care Guide

MAINTENANCE

Removing and Replacing the

Gas Control Valve

Removing the Gas Control Valve:

Turn the gas control/

temperature knob to the

“OFF” posion.

HOT

LOW

PILOT

OFF

VERY

HOT

VAC

TO LIGHT PILOT:

PRESS

HOLD

KNOB IN

POSITION

PRESS

IGNITER

BUTTON

UNTIL

PILOT LIGHTS

RELEASE KNOB

WHEN

STATUS

LIGHT

BLINKS

Figure 53 - Turn gas control/temperature knob

OFF.

Turn o the gas at the

manual shut-o valve on the

gas supply pipe.

Figure 54 - Gas valve in “o” posion.

Drain the water heater. Refer

to the “Draining and Flushing

the Water Heater” secon

(see page 29) and follow the

procedure.

Disconnect the

igniter

wire from the igniter lead

wire. Use needle nose pliers

to disconnect the

red (+) and

white (-) thermopile wires. Disconnect

pilot tube (7/16” wrench) and

manifold tube (3/4” wrench) at

the gas control valve/thermostat.

NOTICE: L.P. Gas systems use reverse

(le-hand) threads on the manifold

tube.

SCALDING

RISK

INCREASES

WITH

HOTTER

WATER

HOT

LOW

PILOT

OFF

VERY

HOT

VAC

TO LIGHT PILOT:

PRESS

HOLD

KNOB IN

POSITION

PRESS

IGNITER

BUTTON

UNTIL

PILOT LIGHTS

RELEASE KNOB

WHEN

STATUS

LIGHT

BLINKS

STATUS

RED

WHITE

FLAMES

STATUS

LIGHT

CODE

Figure 55 - Gas valve connecons.

Disconnect the ground joint

union in the gas piping.

Disconnect the remaining

pipe from the gas control valve/

thermostat.

Figure 56 - Ground joint union connecon.

To remove the gas control

valve/thermostat, thread a 4”

secon of gas pipe into the

inlet and use it to turn the gas control

valve/thermostat (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/thermostat may result.

Replacing the Gas Control Valve:

To replace the gas control valve/

thermostat, reassemble in reverse

order. When replacing the gas control

valve/thermostat, thread a 4” secon

of gas pipe into the inlet and use it to

turn the gas control valve/thermostat

(clockwise.) DO NOT OVER TIGHTEN,

damage may result.

SCALDING

RISK

INCREASES

WITH

HOTTER

WATER

HOT

LOW

PILOT

OFF

VERY

HOT

VAC

TO LIGHT PILOT:

PRESS

HOLD

KNOB IN

POSITION

PRESS

IGNITER

BUTTON

UNTIL

PILOT LIGHTS

RELEASEKNOB

WHEN

STATUS

LIGHT

BLINKS

STATUS

RED

WHITE

FLAMES

STATUS

LIGHT

CODE

4”

Gas Pipe

Figure 57 - Gas control valve with threaded

pipe.

• 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 indi-

cate a leak. Correct any leak found.

Figure 58 - 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 23.

• If addional informaon is required,

contact our Technical Assistance

Hotline which is listed on the water

heater’s warranty sheet.

Residenal Gas Water Heater Use and Care Guide • 33

REPAIR PARTS

When ordering repair 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 Vent Terminaon Hood

2 Wall Plate

3*** Vent Pipe

4 Cold Water Inlet Nipple/Diptube

5 Side Connect - Hot Outlet

6 T&P Valve

7 Gas Control Valve/Thermostat

8 Side Connect - Cold Inlet

9** Discharge Pipe

10 Drain Valve

11 Outer Gas Door

12 Manifold Door Assembly (behind outer door)

13** Floor Drain

14 Metal Drain Pan

15 Flexible Manifold Tube

16 Sediment Trap

17 Ground Joint Union

18 Manual Gas Shut-o Valve

19 Gas Supply

20 Bae Assembly

21 Rang Plate

22 Anode Rod (Under Cap)

23 Hot Water Outlet

24 Inlet Water Shut-o Valve

25 Union (Water Connecon)

26 Air Inlet Snorkel

27 Air Tower

28*** Airbox

29** Thermal Expansion Tank

30* Sheet Metal Burner

31* Gas Orice

32* Gas Manifold

33* Manifold Door Gasket

34* Manifold Door

35* Two Piece Grommet with Clip

36* Viewport

37* Flexible Manifold Tube

38* Pilot

39* Thermopile

40* Pilot Shield

***

Pictured on next page.

Items not supplied with the water heater.

During operaon the vent pipe and airbox can get hot.

2 3

Front View

Rear View

REPAIR PARTS

34 • Residenal Gas Water Heater Use and Care Guide

REPAIR PARTS

Flare

Nut

††

†

Natural gas and Propane (LP) main burner with igniter

assembly for 38k to 42k Btu/hr models

Flare

Nut

††

†

Natural gas and Propane (LP) main burner with igniter

assembly for 47k Btu/hr models

NOTES:

† The orice on Natural gas models has Right-hand thread. The orice on Propane (LP) models has Le-hand thread.

† † For Natural gas models the Flare Nut has Right-hand thread. For Propane (LP) models the Flare Nut has Le-hand thread.

REPAIR PARTS

Residenal Gas Water Heater Use and Care Guide • 35

NOTES

Limited Warranty provided by Manufacturer.

AO Smith GDV-40L 301 ProLine® 40-Gallon Direct Vent Liquid Propane Gas Water Heater

Product's Documents

Manual - ProLine® Direct Vent Manual (100381379)

Specifications

AO Smith GDV-40L 301 Questions and Answers