AO Smith GPVNT-50 ProLine XE 50-Gallon Ultra-Low NOx Gas User Manual

Residential Gas

Water Heater

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.

Power Vented Ultra Low Nox Gas Water Heater with the

Flammable Vapor Igni on Resistant Safety System

Read this manual and the labels on the water heater before you install,

operate, or service it. If you have diﬃ culty following the direc ons, or

aren’t sure you can safely and properly do any of this work yourself:

• Call our Technical Assistance Hotline which is listed on your warranty. 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 ra ng

plate.

• Incorrect installa on, opera on, or service can damage the water heater, your

house and other property, and present risks including ﬁ re, scalding, electric

shock, and explosion, causing serious injury or death.

Do not store or use gasoline or other

ﬂ 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 sup-

plier, call the ﬁ re department.

Installa on and service must be per-

formed by a qualiﬁ ed installer, service

agency or the gas supplier.

WARNING: If the informa on in

these instruc ons is not followed

exactly, a ﬁ re or explosion may

result causing property damage,

personal injury or death.

LOW LEAD

CONTENT

Table of Contents Page

IMPORTANT SAFETY INFORMATION ..........................................3-6

GETTING STARTED ...................................................................7-15

INSTALLATION ........................................................................ 16-26

OPERATION ............................................................................27-28

TROUBLESHOOTING .............................................................29-34

MAINTENANCE ...................................................................... 35-37

ELECTRICAL CONNECTIONS ........................................................ 38

REPAIR PARTS ........................................................................39-40

100362953_2000618730 (REV. A)

March 2023

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2 • Power Vented Ultra Low Nox Gas Water Heater - Use and Care Guide

COMPLETED INSTALLATION TYPICAL

Hot water line

Vent Pipe

Cold water line

Expansion tank

(Connected to cold water inlet)

Blower

T&P relief valve

T&P discharge pipe

Drain

Metal drain pan

discharge pipe

Drain valve

Metal drain pan

Sediment trap

Gas Supply

'ĂƐƐƵƉƉůǇƐŚƵƚŽī

Gas control valve/

thermostat

Ground Joint Union

FV Sensor

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Power Vented Ultra Low Nox Gas Water Heater - Use and Care Guide • 3

IMPORTANT SAFETY INFORMATION

Important informa on to keep

Fill out this sec on and keep this

manual in the pocket of the water

heater for reference.

Date Installed:

Model number:

Serial number:

Maintenance performed:* Date:

This is the safety alert symbol. It is used to alert you to

poten al physical injury hazards. Obey all safety mes-

sages that follow this symbol to avoid possible property

damage, serious injury or death. Do not remove any per-

manent instruc ons, labels, or the ra ng plate from either the outside of

the water heater or on the inside of the access panels. Keep this manual

near the water heater.

DANGER

Read and follow all safety messages and instruc ons in

this manual.

DANGER indicates hazardous situa-

 on that, if not avoided, will result

in death or serious injury.

WARNING

WARNING indicates a hazardous

situa on that, if not avoided, could

result in death or serious injury.

CAUTION

CAUTION indicates a hazardous

situa on that, if not avoided, could

result in minor or moderate injury.

NOTICE

NOTICE indicates prac ces not

related to physical injury.

WARNING! If the informa on in these instruc ons is not followed exactly,

a ﬁ re or explosion may result causing property damage, personal injury or

death. Do not store or use gasoline or other ﬂ 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 ﬁ ed to comply with a maximum weighted average of 0.25%

lead content as required in some areas.

*Drain and ﬂ ush tank and remove and

inspect anode rod a er ﬁ rst six months

of opera on and at least annually

therea er. Operate the Temperature

and Pressure Relief Valve (T&P) annu-

ally and inspect T&P valve every 2-4

years (see the label on the T&P valve for

maintenance schedule). See the Main-

tenance sec on for more informa on

about maintaining this water heater.

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4 • Power Vented Ultra Low Nox Gas Water Heater - Use and Care Guide

SAFETY

IMPORTANT SAFETY INFORMATION

o 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

ra ng plate to determine the type of

gas required. Failure to follow these

instruc ons can result in serious injury

or death from explosion, ﬁ 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-oﬀ 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 ra ng plate. The minimum

supply pressure is for the purpose of

input adjustment.

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

showering.

• To reduce the risk of scalding,

install Thermosta c Mixing Valves

(temperature 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 avail-

able from your local plumbing

supplier. Follow manufacturer’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 tempera-

ture 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) 1½ 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 1½ seconds

155°F (68°C) About 1 second

For informa on about changing the

factory temperature se ng, refer to

“Adjus ng the Temperature” on page

28.

Even if you set the water heater’s gas

control valve to a low se ng, higher

water temperatures may occur in cer-

tain 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.

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Power Vented Ultra Low Nox Gas Water Heater - Use and Care Guide • 5

SAFETY

IMPORTANT SAFETY INFORMATION

• If the water supplied to the water

heater is pre-heated (for example,

by a solar system) the temperature

in the tank may be higher than the

water heater’s temperature se ng.

• Should overhea ng occur or the

burner fail to shut oﬀ , turn oﬀ the

manual gas supply valve to the water

heater and call a qualiﬁ ed person.

To reduce the risk of unusually hot wa-

ter reaching the ﬁ 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 elder-

ly, 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 (ASSE

1070) and many local plumbing codes,

the water heater’s gas control valve

should not be used as the sole means

to regulate water temperature and

avoid scalds.

Properly adjusted Thermosta c Mixing

Valves installed at each point-of-use al-

low you to set the tank temperature to

a higher se ng without increasing 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 con-

taminate 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 Flam-

mable Vapor Igni on

Resistance (FVIR) system.

FVIR is designed to reduce the risk of

ﬂ ammable vapor-related ﬁ 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 ﬁ re/explosion if

the hot surface igniter ignites and

ﬂ ammable vapors have accumulated in

the combus on chamber.

Do not a empt to light this appliance

if you suspect ﬂ ammable vapors have

accumulated inside or outside the

appliance. Immediately call a qualiﬁ ed

person to inspect the appliance. Water

heaters subjected to a ﬂ ammable

vapors incident will show a discolor-

a on on the ﬂ ame arrestor and require

replacement of the en re water heater.

Improper installa on or an inadequate

air supply can also cause the FVIR sys-

tem to disable the water heater.

To reduce the risk of a ﬁ re that could

destroy your home and seriously injure

or kill people:

• 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

ﬂ ammable substances in the vicinity

of this or any other appliance.

• Keep the water heater from becom-

ing wet. Immediately shut the water

heater oﬀ and have it inspected by a

qualiﬁ ed person if you ﬁ nd that the

wiring, thermostat(s) or surround-

ing 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 ﬁ re risk). If the

water heater is subjected to ﬂ ood

condi ons or the thermostat(s) have

been submerged in water, the en re

water heater must be replaced.

• Replace the water heater’s viewport

if glass is missing or damaged. Repair

the combus on chamber door seals

if damaged.

Explosion Risk

High temperatures and

pressures in the water

heater tank can cause an explosion re-

sul ng in property damage, serious in-

jury 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 labo-

ratory maintains periodic inspec on

of the valve produc on process and

cer ﬁ 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 wa-

ter 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). An explosion could occur

if the T&P Relief Valve 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.

WARNING! Hydrogen gas builds up

in a hot water system when it is not

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6 • Power Vented Ultra Low Nox Gas Water Heater - Use and Care Guide 6 • Power Vented Ultra Low Nox Gas Water Heater - Use and Care Guide

SAFETY

IMPORTANT SAFETY INFORMATION

used for a long period (two weeks or

more). Hydrogen gas is extremely

ﬂ 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 ﬂ ow. Do not smoke or

have an open ﬂ 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

qualiﬁ ed person

(licensed plumber,

authorized gas

company personnel, or authorized

service technician) install the ven ng

system using these installa on

instruc ons.

• 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.

Installa on Accessories

Figure 1 - Gas Water Heater Hook-Up Kit

Figure 2 - Install a Pressure Reducing Valve set

to 50 to 60 PSI.

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Power Vented Ultra Low Nox Gas Water Heater - Use and Care Guide • 7

GETTING STARTED

Review all of the instruc ons

before you begin work. (If you

aren’t sure that you can safely

and properly do this work yourself, call

a qualiﬁ ed person, such as a licensed

plumber, to have the work done).

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 design-

cer ﬁ ed by CSA Interna onal

as a Category IV, non-direct

vented water heater which takes its

combus on air either from the installa-

 on area or from air ducted to the unit

from the outside. This water heater

must be installed according to all local

and state codes or, in the absence of

local and state codes, the “Na onal

Fuel Gas Code”, ANSI Z223.1 (NFPA

54)-current edi on. This is available

from the following:

CSA America, Inc.

8501 East Pleasant Valley Road

Cleveland, OH 44131

Na onal Fire Protec on Associa on

1 Ba erymarch Park

Quincy, MA 02269

Check with local code oﬃ cials about

codes governing this installa on. Have

your installa on inspected by a code

oﬃ 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 diﬃ culty follow-

ing the instruc ons, you should not

proceed but have a qualiﬁ 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:

• Common plumbing tools (depend-

ing on what type of water pipes

you have).

• Thread sealant tape or pipe joint

compound approved for potable

water.

• For homes with copper pipes, and

where allowed by local codes, you

may purchase a gas water heater

hook-up kit (available from your

plumbing supplier) with compres-

sion ﬁ  ngs that don’t require

soldering. NOTE: Where allowed by

local codes.

• For homes with plas c pipe, use

threaded connectors suitable for

the speciﬁ c type of plas c pipe

used: CPVC or PEX (cross-linked

polyethylene). Do not use PVC pipe.

• Non-corrosive gas leak detec on

solu on made from hand dish-

washing soap mixed with water (1

part soap to 15 parts water) or chil-

dren’s soap bubbles and a small,

so -bristled brush.

• An appliance dolly or hand truck to

move the water heater.

Recommended Accessories:

• A metal drain pan.

• Automa c water leak detec on

and shut-oﬀ 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

Before installing the water heater, you

must determine the amount of air

needed to supply this water heater

and any other gas appliances in the

same area and provide adequate air for

combus on and ven la on. Consult a

qualiﬁ ed person if you’re unsure of the

proper way to supply air to your water

heater.

WARNING! This gas water heater

requires an adequate source of clean

air for combus on and ven la on.

Without suﬃ cient air, your water

heater may emit excessive and

abnormal amounts of carbon

monoxide.

Before beginning:

Calculate total BTU/HR ra ng of all ap-

pliances.

To calculate the combus on air and

ven la on required, add up the total

BTU/HR ra ngs of all gas burning ap-

pliances (e.g., water heaters, furnaces,

clothes dryers) in the same area.

Your water heater’s BTU/HR ra ng is on

the ra ng plate, located next to the gas

control valve/thermostat. The BTU/HR

ra ngs should be on the other appli-

ances’ ra ng plates. If you have trouble

determining the BTU/HR ra ngs,

contact the manufacturer or have a

qualiﬁ ed person determine the ven la-

 on requirements. NOTICE: If you are

replacing your old water heater with

one that has a higher BTU/HR ra ng,

the amount of ven la on required may

be greater.

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8 • Power Vented Ultra Low Nox Gas Water Heater - Use and Care Guide

GETTING STARTED

Example:

Gas Burning Appliance BTU/HR Ra ng

Gas Water Heater 40,000

Furnace 75,000

Dryer 20,000

Total 135,000

Your Appliances:

Gas Burning Appliance BTU/HR Ra ng

Gas Water Heater

Total

Table 2 provides examples of minimum

square footage (area) required for

various BTU/HR totals. Areas used for

storage or which contain large objects

containing less air than is assumed for

the room sizes in Table 2 – see Op on

A for more speciﬁ c calcula ons.

Op on A: Installa on without

outside ven la on (not recom-

mended)

Ven la on with outside air is recom-

mended for all installa ons. Even if

the water heater is installed in a large,

open room inside the house, outdoor

air is usually needed because modern

homes are very  ghtly sealed and

o en do not supply enough air to the

water heater. However, when installed

in a large indoor space, it may be pos-

sible to provide enough air without

outside ven la on. If you are unsure if

your installa on loca on has enough

ven la on, contact your local gas

u lity company or code oﬃ cials for a

safety inspec on.

The following instruc ons will help de-

termine if it may be possible to install

without outside ven la on. If there is

not enough ven la on, you will need

to ven late with outside air.

Check for Chemicals:

Air for combus on and ven la on

must be clean and free of corrosive or

acid-forming chemicals such as sulfur,

ﬂ uorine, and chlorine. Ven la on with

outside air will reduce these chemicals,

but it may not completely eliminate

them. Failure due to corrosive chemi-

cals is not covered by the warranty.

Examples of loca ons that require

outside air due to chemicals include:

• Beauty salons

• Photo processing labs

• Indoor pools

• Laundry, hobby, or cra rooms

• Chemical storage areas

Products such as aerosol sprays, de-

tergents, bleaches, cleaning solvents,

gasoline, air fresheners, paint and

varnish removers, and refrigerants

should not be stored or used near the

water heater.

A1: Calculate the air volume of

the room

Air requirements depend on the size of

the room.

Floor Area (Square feet) X Ceiling

Height (feet) = Room Volume (cubic

feet)

If there are large objects in the room

(e.g., refrigerator, furnace, car), sub-

tract their volume from the volume of

the room to get a be er es mate of

the air available.

Room Volume – Object Volume = Air

Volume

Table 2

BTU/HR Minimum Square Typical Room

Input Feet with 8’ Ceiling with 8’ Ceiling

30,000 188 9 x 21

45,000 281 14 x 20

60,000 375 15 x 25

75,000 469 15 x 31

90,000 563 20 x 28

105,000 657 20 x 33

120,000 750 25 x 30

135,000 844 28 x 30

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Power Vented Ultra Low Nox Gas Water Heater - Use and Care Guide • 9

GETTING STARTED

A2: Calculate required air volume

A water heater installed in an unconﬁ ned

a c or garage requires that the space

be at least 50 cubic feet per 1,000 BTU/

HR of the total input for all gas burning

appliances in the same area.

[Total BTU/HR/1000] x 50 = Cubic feet

of air required.

Example:

(135,000 / 1000) x 50 = 6,750

If the air volume of the room is less

than the required air volume, you must

provide two permanent outside air

openings that draw in suﬃ cient air. Use

Op on B.

If the air volume of the room is greater

than the required air volume, it may

be possible to install the water heater

without outside ven la on.

A3: Verify that combus on ven-

 la on is adequate

Because modern homes are o en well-

sealed to prevent dra s, even a large

room may not provide enough combus-

 on air without ven la on. However,

your power-vented system could iden-

 fy inadequate ven la on by triggering

an error code (See page 32) . S ll,

you must follow all instruc ons in this

sec on to ensure adequate ven la o n .

Op on B: Install with outside

ven la on

Ven la on with outside air is recom-

mended, and, for most installa ons, is

needed. There may be exis ng ven la-

 on that is adequate, or you may need

to add more ven la on.

Supplying outside air typically requires

two openings. One opening must be

within 12 inches from the ﬂ oor and

the second opening must be within 12

inches from the ceiling. Although a single

opening is not preferred, you may use a

single opening to outside air if the mini-

mum free area is sized according to Table

3. Two openings must be used when

ven la ng with air from another room.

The outside air can be taken from a

crawl space or a c open to the out-

doors and adequately ven lated. You

may use ver cal or horizontal ducts.

B2: Determine type of ven la on

There are several types of ven la on

that can be used :

1. Direct to outdoors

2. Ver cal ducts

3. Horizontal ducts

4. Single opening (not recom-

mended; must be at least 100

square inches. Not appropriate

for conﬁ ned spaces smaller than

50 cubic feet per 1,000 BTU/HR as

calculated in sec on A or when

ge ng air from another room.)

5. From a larger room inside the

house (not recommended – refer

to sec on A above to determine if

the combined volume of the rooms

may be adequate).

B3: Determine minimum free

area required for each vent

opening

The size of the vent openings depends

on the total BTU/HR ra ng of all appli-

ances in the space (use your calcula on

from “Before beginning”) and the type

of vent used. Table 3 provides the mini-

mum free area for each vent opening

depending on the type of ven la on.

B4: Calculate minimum size of

vent openings and ducts

The vent cross-sec onal area needed to

provide the free area depends on the

covering on the vent openings. Typical

vents use louvers or grilles to protect

the opening. The louver or grill itself

blocks some of the free area, so the

opening may need to be larger to meet

the minimum free area requirements.

Use the following formula to calculate

the required cross-sec onal area:

Table 3

Minimum Free Area of Permanent Openings for Ven la on and Combus on Air

Supply – All Air from Outdoors Only.

Based on the total BTU/HR input ra ng for all gas burning appliances within a

conﬁ ned space.

Opening Source Minimum Free Area

Per Opening (sq. in.)

*Direct to outdoors 1 sq. in. per 4,000 BTU/HR (see ﬁ gure on page 10)

Ver cal ducts 1 sq. in. per 4,000 BTU/HR (see ﬁ gure on page 10)

Horizontal ducts 1 sq. in. per 2,000 BTU/HR (see ﬁ gure on page 10)

Single Opening 1 sq. in. per 3,000 BTU/HR (see ﬁ gure on page 10)

*These openings connect directly with the outdoors through a ven lated a c, a

ven lated crawl space, or through an outside wall.

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10 • Power Vented Ultra Low Nox Gas Water Heater - Use and Care Guide

GETTING STARTED

Cross-sec onal area = minimum free

area required ÷ percent free area of

covering (in decimals – e.g., 60% = .6)

For example, an installa on area that

requires openings with 100 square

inches of free area would need 134

square inch openings if using metal

louvers rated at 75% free area (100 sq.

in. ÷ .75 = 134 sq. in.).

If you do not know the % free area for

your louver or grill, use the following

values:

• For wood louvers or grilles: 20%

• For metal louvers or grilles: 60%

Follow these rules to ensure that vents

and ducts provide adequate air ﬂ ow:

• Each vent opening must be no

smaller than 100 square inches .

• Ducts must have the same cross-

sec onal area as free area of the

opening.

• All dimensions for rectangular

ducts must be no less than three

inches.

• All screens must have mesh ¼” or

larger.

• Moveable louvers must be locked

open or interconnected with the

equipment so that they open au-

toma cally during opera on.

• Keep louvers and grills clean and

free of debris or other obstruc-

 ons.

B5: Check that air source is

clean and free of chemicals

Air for combus on and ven la on

must be clean and free of corrosive

or ﬂ ammable chemicals. A failure due

to corrosive chemicals in the air is not

covered by the warranty. Combus-

 on air must be free of acid-forming

chemicals such as sulfur, ﬂ uorine, and

chlorine. Be sure that air at the vent

inlets is free of such chemicals.

B6: Verify that combus on

ven la on is adequate

Your power-vented system could trigger

an error code (page 32) if there is

insuﬃ cient combus on air. However,

you must also ensure that adequate

combus on air is available by following

all instruc ons in this sec on. Please

verify your calcula ons before you

proceed.

Combus on Air Supply Op ons

Figure 3 - Direct to outdoors openings

Figure 4 - Vertical duct openings

Figure 5 - Vertical duct openings

Figure 5 - Horizontal duct openings

Figure 6 - Single opening

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Power Vented Ultra Low Nox Gas Water Heater - Use and Care Guide • 11

GETTING STARTED

Ven ng

WARNING!

• Carbon Monoxide Hazard. This

water heater must be supplied

with adequate air and vented to

the outdoors. The vent system

must be installed by a qualiﬁ ed

person. Examples of a qualiﬁ ed

person include gas technicians,

authorized gas company

personnel, and authorized service

technicians.

• Check to make sure the vent pipe

is not blocked in any way. Do not

common vent this water heater

with any other appliance. Do

not install in the same chase or

chimney with a metal or high-

temperature plastic from another

gas or fuel burning appliance.

• Failure to properly vent the water

heater can result in severe injury

or death from carbon monoxide

poisoning.

• Do not use Schedule 40 PVC

ven ng if used in areas with

ambient temperatures above

110°F.

This water heater must be properly

vented for removal of exhaust gases

to the outside atmosphere. Correct

installation of the vent pipe system is

mandatory for the safe and efficient

operation of this water heater and is

an important factor in the life of the

unit.

The vent pipe must be installed in

accordance with state and local codes,

or in the absence of such, the National

Fuel Gas Code, NFPA 54, ANSI Z223.1-

current edition.

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.

Vent Pipe Material

The following plastic materials may be

used for exhaust outlet piping subject

to state and local codes.

• 2 or 3 inch Schedule 40 PVC,

CPVC, ABS, and polypropylene

• 2 or 3 inch Schedule 40 or PVC,

CPVC, ABS, and polypropylene

• DWV Pipe is acceptable

Reference Table 5 for more

information.

Use of cellular core PVC (ASTM

F891), cellular core CPVC, or Radel®

(polyphenolsulfone) in non-metallic

venting systems is prohibited.

Plastic pipe and fittings are available

through most plumbing suppliers.

Always check the marking on the pipe

to make sure you are using the correct

material. See also “Connect Vent Pipe

to Blower” on page 23.

Vent Pipe Installa on

The following guidelines should be

followed when installing the exhaust

outlet piping:

• Venting should be as direct as

possible with a minimum number

of pipe fittings.

• Vent diameter must not be

reduced unless specifically noted

in the installation instructions.

• Support all horizontal pipe runs

every four feet and all vertical

pipe runs every six feet or

according to local codes.

• Vents run through unconditioned

spaces where below freezing

temperatures are expected

should be properly insulated to

prevent freezing. For horizontal

runs, wrap the vent pipe with

self-regulating 3 or 5 watt heat

tape. The heat tape must be

U.L. listed and installed per the

manufacturer’s instructions.

• Do not connect this venting

system with an existing vent or

chimney.

• Do not common vent with the

vent pipe of any other water

heater or appliance.

The exhaust outlet piping and

termination may be installed

in one of the following type

terminations:

1.) Standard Horizontal;

2.) Vertical.

All pipe, fittings, pipe cement, primers

and procedures must conform to

American National Standard Institute

and American Society for Testing and

Materials (ANSI/ASTM) standards in

the United States. This water heater

has been design certified by CSA

International for use with the listed

plastic vent pipe material.

DO NOT use vent elbows in this vent

pipe installation. See “Incorrect

Fittings” in Figure 8.

All joints in the outlet piping must be

properly cemented. Size and cut all

piping before cementing.

1. Cut the pipe end square and

remove all ragged edges and

burrs. Make sure the inside of the

pipe is clean and free of cuttings

and loose dirt. Chamfer the end

and apply primer to the fitting

and pipe.

2. Using a suitable grade of pipe

cement, apply a moderate, even

coat inside the fitting. Apply a

liberal amount of cement to the

outside of the pipe to socket

depth. NOTICE: It is important to

select the proper pipe cement for

the type plastic pipe being used.

3. Assemble the parts quickly while

the cement is still wet. Twist the

pipe 1/4 turn during insertion and

hold for 30 seconds.

GETTING STARTED

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12 • Power Vented Ultra Low Nox Gas Water Heater - Use and Care Guide

GETTING STARTED

Vent Pipe Length

Size the exhaust outlet as specified

in Table 4, page 12. This table lists

the maximum allowable length in feet

of the exhaust outlet pipe as related

to the number of required elbows

and the termination. The specified

maximum lengths are for exhaust

pipe systems. Minimum pipe length is

3 feet with one elbow.

Table 4: Vent Pipe Lengths

WATER

HEATER

MODEL

HEATER

INPUT (Btu/

hr)

VENT SIZE

(Inside Diam.)

PRESSURE

SWITCH

SETTING

MAX. EQUIVALENT VENT

LENGTH

MIN. EQUIVALENT VENT

LENGTH

40 & 50 gal. 42,000 2” - 0.27 in. w.c. 50 ft. + termination elbow 7 ft. + termination elbow

40 & 50 gal. 42,000 3” - 0.27 in. w.c. 125 ft. + termination elbow 50 ft. + termination elbow

Equivalent lengths of straight pipe for various elbows using Schedule 40 PVC, CPVC and polypropylene.

Vent Pipe Size Elbow Type Short Sweep/Short Radius Long Sweep/Long Radius

2” or 3” 90° 8 ft. 5 ft.

2” or 3” 45° 4 ft. 2.5 ft.

Notes:

1. Use long radius elbows where possible. Minimum distance between 90º elbows should be 6” wherever possible.

2. Venting systems may use a maximum of five (5) 90° elbows.

3. Use proper screen termination (see Figure 8).

High Ambient Temperature

WARNING! Do not install in

environments above 140°F.

This heater requires room air to lower

the ﬂ ue gas temperatures before the

gases pass through the vent system.

The dilu on air inlets are located on

the rear of the blower assembly.

As the room temperature rises, the

ability to lower the ﬂ ue gases tempera-

ture lessens so special a en on to the

choice of ven ng material is required.

Establishing the ambient temperatures

where the heater and the ven ng is

installed is very important, especially

in regions with warmer climates or any

region that experiences hot summers.

Ambient condi ons between 105°F

and 140°F require that the ven ng

material be either CPVC or polypropyl-

ene. Areas that can experience high

ambient environments include closets,

alcoves, areas under staircases, a cs-

especially in metal roofed buildings,

areas with restricted air movement,

rooms with large solar gains, metal

sheds, industrial or commercial enter-

prises and ven ng systems exposed

to direct sunlight. For high tempera-

ture environments (105°F - 140°F),

obtain high limit switch upgrade Kit

#100112696 and use the higher rated

vent piping. Use of cellularcore PVC

(ASTM F891), cellular core CPVC, or

Radel® (polyphenylsulfone) in non-me-

tallic ven ng systems is prohibited.

Table 5:

Vent Pipe

Material

Pipe and fitting

nomenclature

Applicable Standard

PVC DWV ASTM D2665 or CSA B181.2

PVC Sch 40 ASTM D1785 or CSA B137.3

PVC SDR series ASTM D2241 or CSA B137.3

PVC BH ULC S636‡, UL 1738§

CPVC CPVC 41 ASTM D2846 or CSA B137.6

CPVC Sch 40 ASTM F441 or CSA B137.6

CPVC SDR series ASTM-F442

CPVC BH ULC S636‡, UL 1738§

ABS Sch 40 DWV

ASTM D2661§, CSA B181.1§ or ULC

S636‡

Polypropylene n/a ULC S636‡, UL 1738§

‡ Applicable to Canada only.

§ Applicable to the United States only.

Note: Use of cellular core PVC (ASTM F891), cellular core CPVC, or

Radel®(polyphenysulfone) in non-metallic venting systems is prohibited.

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Power Vented Ultra Low Nox Gas Water Heater - Use and Care Guide • 13

GETTING STARTED

Table 6:

PVC pipe

materials (solid

pipe)

DWV ASTM-D2665

Schedule 40

ASTM-D1785, SDR

Series ASTM-D2241

CPVC pipe

materials

CPVC 41

ASTM-D2846

Schedule 40

ASTM-F441

SDR Series

ASTM-F442,

ABS pipe

materials

DWV ASTM-D2661

Schedule 40

Polypropylene

vent system

UL-1738

Note: If local codes require venting

to be marked suitable for use as gas

venting, type BH venting may be used.

The fittings, other than the

Termination should be equivalent to:

Table 7:

PVC pipe

PVC DWV ASTM

D-2665

CPVC pipe CPVC ASTM F-438

ABS pipe

ABS ASTM

D-2661/3311

Polypropylene

vent system

UL-1738

If CPVC or ABS pipe and fittings are

used, the proper cement must be

used for all joints, including joining the

pipe to Termination (PVC Material).

If local codes do not allow the use of

the PVC termination when a material

other than PVC is used for venting, an

equivalent fitting of that material may

be substituted if the screen in the PVC

terminal is removed and inserted into

the new fitting.

This water heater is supplied with

the applicable vent screens. A 90°

termination elbow is optional.

ASTM D-2564 Grade Cement should

be used on PVC Materials and

ASTM F-493 Grade Cement on CPVC

Materials.

Note: Polypropylene vent systems

require separate adaptor, termination,

and elbows (field supplied). It is

recommended to use InnoFlue®

SW Residential products from

Centrotherm (www.centrotherm.

us.com).

Vent Termina ons

The exhaust outlet must be installed

with the minimum clearances shown

in Figure 9.

In addition to maintaining the

minimum clearances, the vent should

terminate according to the following

guidelines:

1. Do not expose any reducers or

bushings to outdoor ambient

temperatures.

2. The vent for this appliance shall

not terminate:

• Over public walkways;

• Near soffit vents or crawl

space vents or other areas

where condensate or vapor

could create a nuisance,

hazard, or cause property

damage;

• Where condensate vapor

could cause damage or

could be detrimental to the

operation of regulators, relief

valves, or other equipment;

• Where condensate may

cause hazardous frost or ice

accumulations on adjacent

property surfaces;

• Where children or animals

could block pipes;

• Too close to shrubs or bushes.

3. Caulk all cracks, seams and joints

within 6 feet horizontally above

and below the vent.

Ver cal Termina on

The vertical exhaust outlet requires a

return bend or two medium or long

sweep radius 90° elbows to keep the

exhaust outlet downward and prevent

entry of rain. Do not include these

elbows when calculating the maximum

allowable vent pipe because they have

already been considered in the vent

tables. The vertical exhaust outlet

termination is a 2 inch or 3 inch pipe

which must be at least 12 inches

above the roof line or anticipated

snow levels. See Figure 7. Follow all

applicable code requirements.

VĞƌƟĐĂů vent tĞƌŵŝŶĂƟŽŶ

ŶƟĐŝƉĂƚĞĚ

^ŶŽǁ>ĞǀĞů

12” Min.

ǆŚĂƵƐƚ

Air

KƵƚůĞƚ

ZŽŽĨ

^ƚĂŶĚĂƌĚ,ŽƌŝǌŽŶƚĂůdĞƌŵŝŶĂƟŽŶ

ϭϮDŝŶĂďŽǀĞŐƌĂĚĞŽƌ

ĂŶƟĐŝƉĂƚĞĚƐŶŽǁůĞǀĞů

KƵƚƐŝĚĞtĂůů

sĞŶƚWŝƉĞ

Vent

dĞƌŵŝŶĂů

sĞŶƚƉŝƉĞŵƵƐƚƐůŽƉĞ

ĚŽǁŶǁĂƌĚƚŽǁĂƌĚǁĂůů

ϭϴƉĞƌϱŌŽǁŶǁĂƌĚ

ƐůŽƉĞĂƐƐŝƐƚƐĐŽŶĚĞŶƐĂƚĞ

ĚƌĂŝŶĂŐĞ

Figure 7 - Vent Terminations

Printed on: 7/6/2023 9:40:13 AM CT

GETTING STARTED

14 • Power Vented Ultra Low Nox Gas Water Heater - Use and Care Guide

A. 12 in (30 cm) min. clearance above grade, veranda,

porch, deck, balcony, or maximum anticipated snow

level.

B. Clearance to window or door that may be opened:

4 ft (1.2 m) below or to side of opening; 1 ft (300 mm)

above opening.

C. Clearance to permanently closed window.**

D. Vertical clearance to ventilated soffit located above the

terminal within a horizontal distance of 2 feet (61 cm)

from the center line of the terminal.**

E. Clearance to unventilated soffit.**

F. Clearance to outside corner. **

**Clearance in accordance with local installation codes and the requirements of the gas supplier.

US Installations

G. Clearance to inside corner.**

H. Clearance to each side of center line extended above meter/

regulator assembly.**

I. Clearance to regulator vent outlet.**

J. 12 in (300 mm) clearance above or 4 ft (1.2 m) clearance

below or to the side of non-mechanical air supply inlet to

building or the combustion air inlet to any other appliance.

K. Clearance to a mechanical air supply inlet: 3 ft (91 cm) above

if within 10 ft (3 m) horizontally.

L. Clearance above paved sidewalk or paved driveway located

on public property: 7 ft (2.13 m).**

M. Clearance under veranda, porch, deck, or balcony.**

Figure 9 - Minimum Termination Clearance for Outlet Vent

Standard Horizontal Termina on

The standard horizontal exhaust

outlet termination is a 2 inch or 3

inch pipe which terminates at least

12 inches above grade or anticipated

snow levels. To prevent potential

condensate from collecting in the

venting system, slope the vent at a

downward pitch of 1/8” per 5 ft. away

from the water heater.

Install the correct size coupling at

the outside wall on the exhaust to

prevent the termination from being

pushed inward. Follow all applicable

code requirements.

GETTING STARTED

INCORRECT FITTINGS

90° Vent

Elbow

45° Vent

Elbow

Tee Connector

CORRECT FITTINGS

90° Medium

Sweep Elbow

45° Sweep

Elbow

90° Long

Sweep Elbow

VENT LENGTH

GREATER THAN 20

EQUIVALENT FT.

VENT PIPE SCREENS FOR HEATERS WITH RATED INPUTS OF 50K BTU/HR OR LESS

2” VENTING (LONG)

VENT LENGTH

LESS THAN 20

EQUIVALENT FT.

2” VENTING (SHORT)

VENT LENGTH

GREATER THAN 50

EQUIVALENT FT.

3” VENTING

VENT LENGTH

LESS THAN 50

EQUIVALENT FT.

3” VENTING

NOTE: VENT SCREENS ARE SUPPLIED WITH THE WATER HEATER.

Figure 8 - Vent Termination Fittings

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Power Vented Ultra Low Nox Gas Water Heater - Use and Care Guide • 15

GETTING STARTED

Gas Piping

Gas piping must be installed according

to local and state codes or, in the ab-

sence 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.

Manual gas

shut-oī valve

Sediment Trap

Check with local

ƵƟůŝƚǇĨŽƌ

minimum height

Ground

Joint

Union

3” Minimum

Figure 10 - Gas Piping

1. Install a readily accessible manual

shut-oﬀ valve in the gas supply line

as recommended by the local u lity.

Know the loca on of this valve and

how to turn oﬀ the gas to this unit.

2. Install a Sediment Trap as shown in

the Gas Piping ﬁ gure (Figure 10).

The Sediment Trap must be no less

than three inches long for the ac-

cumula on of dirt, foreign material,

and water droplets.

3. Install a ground joint union between

the gas control valve and the manual

gas shut-oﬀ valve. This is to allow

easy removal of the gas control

valve.

4. Turn the gas supply on and check

for leaks. Use a small, so -bristled

brush to apply a hand dishwashing

soap and water mixture (1 part soap

to 15 parts water) or children’s soap

bubbles to all connec 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 (3.5

kPa), disconnect the gas line at the

manual shut oﬀ valve and cap the gas

line. Do not subject the water heater’s

gas control valve or manual shut oﬀ

valve to more than ½ psi (3.5 kPa) pres-

sure for any reason. If you are pressure

tes ng the gas line with test pressure of

½ psi (3.5 kPa) or less, you may isolate

the water heater from the gas line by

closing the manual shut oﬀ valve.

Solar Installa on

If this water heater is used as a solar

storage heater or as a backup for the

solar system, the water supply tempera-

tures 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 sup-

ply line to limit the supply temperature

to 120°F. The unit must be set to Stan-

dard Mode. (See “Opera ng Modes” on

page 28).

NOTICE: Solar water hea ng systems can

o en supply water with temperatures

exceeding 180°F and may result in water

heater malfunc on.

Printed on: 7/6/2023 9:40:13 AM CT

16 • Power Vented Ultra Low Nox Gas Water Heater - Use and Care Guide

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 stan-

dards. There have likely been plumb-

ing 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 plumb-

ing 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 de-

vices you need to comply with current

codes and assure that your new water

heater performs at its best. Check

with your local plumbing oﬃ 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 with a 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. Connect the water

pressure gauge to an outside faucet

and measure the maximum water

pressure experienced throughout a

24-hour period (highest water pres-

sures o en occur at night).

Figure 11 - Use a Water Pressure Gauge to make

sure your home’s water pressure is not too

high.

To adjust your home’s water pressure:

Locate your home’s Pressure Reduc-

ing 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 PRV, install one on the home’s

main water supply line and set it to

between 50 and 60 psi. Pressure Re-

ducing Valves are available from 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 heater leak, or had to repair

appliances connected to the plumb-

ing 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 recom-

mend installing an expansion tank if

your home does not have one. Plumb-

ing codes require a properly pressur-

ized, properly sized Thermal Expan-

sion Tank in almost all homes.

Figure 12 - A Thermal Expansion Tank helps

protect the home’s plumbing system from pres-

sure spikes.

HOW: Connect the Thermal Expan-

sion Tank (available from 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

before applying water pressure to the

expansion tank. 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

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Power Vented Ultra Low Nox Gas Water Heater - Use and Care Guide • 17

INSTALLATION

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 backﬂ ow preven-

ters and check valves to restrict water

from your home reentering the public

water system. Backﬂ ow preventers are

o en installed in water meters and

may not be readily visible. As a result,

most plumbing systems today are now

“closed,” and almost all homes now

need a Thermal Expansion Tank.

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 oc-

casionally runs for no apparent reason

(usually brieﬂ y at night), that may be

due to thermal expansion increasing

the water pressure temporarily.

✓

Water Pipe and

Tank Leaks

Discharge line 3/4” Min.

Do not cap or plug.

6” Max.

Drain

Metal drain pan

Figure 13 - A metal drain pan piped to an ad-

equate drain can help protect flooring from leaks

and drips.

Leaks from plumbing pipes or from the

water heater itself can damage prop-

erty and could cause a ﬁ re risk.

• Install an automa c leak detec on

and shutoﬀ device (available from

your local plumbing supplier). These

devices can detect water leaks and

can shut oﬀ the water heater’s water

supply if a leak occurs.

• Install a metal drain pan (available

from your local plumbling supplier)

under the water heater to catch

condensa on or leaks from the pip-

ing 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

two inches wider than the diameter

of the water heater. Install the drain

pan so the water level would be lim-

ited to a maximum depth of 1-3/4”.

The pan must not restrict air ﬂ 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 manufac-

turer’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.

Figure 14 - Thermostatic 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 ﬁ xtures. If you aren’t 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 qualiﬁ ed person.

Printed on: 7/6/2023 9:40:13 AM CT

18 • Power Vented Ultra Low Nox Gas Water Heater - Use and Care Guide

INSTALLATION

Step 2:

✓

Verify that the

loca on is

appropriate

WARNING! Do not store or use

ﬂ ammable materials, vapors, or

liquids in the same loca on where this

water heater is installed.

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.

• In a metal drain pan piped to an

adequate drain.

• 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 combustible

surfaces as stated on the rating

plate. Refer to the minimum

clearances listed on the rating

plate on the water heater.

• On a ﬂ oor that can support the

weight of a water heater full of water.

You will also want to follow these

guidelines while considering an appro-

priate loca on:

• Do not install near air-moving

devices such as exhaust fans,

ven la on systems, or clothes

dryers.

• Do not obtain ven la ng air for

the furnace/air handler from the

same space as the water heater.

Ensure that any return air ducts

near the water heater are sealed.

• If the water heater is located

in an area subject to lint, dust,

or oily vapors, at least annually

check and clean the air ﬁ lter. See

Maintenance sec on for steps on

cleaning the air ﬁ lter.

• Do not install in a bathroom,

bedroom, or any occupied room

normally kept closed.

• If the water heater is installed di-

rectly on carpe ng, it shall be in-

stalled on a metal or wood panel

extending beyond the full width

and depth of the water heater

by at least 3 in (76.2mm) in any

direc on. If the water heater is

installed in an alcove or closet,

the en re ﬂ oor shall be covered

by the panel.

• If your area is prone to earth-

quakes, use special straps as

required by local building codes.

NOTICE: The state of California re-

quires bracing, anchoring, or strap-

ping 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,

ﬂ ooding, or other risks.

Vehicle

Stop

Drain

Pan

Figure 15 - In a garage, install a vehicle stop to

avoid water heater damage.

• Avoid loca ons such as a cs, up-

per ﬂ oors, or where a leak might

damage the structure or furnish-

ings. Due to the normal corrosive

ac on of water, the tank will

eventually leak. To minimize prop-

erty 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 surrounding

area regularly and ﬁ x any leaks

found.

Step 3:

✓

Removing the old

water heater

Read each installa on step and

decide if you have the neces-

sary skills to install the water

heater. Only proceed if you are comfort-

able you can safely perform the work. If

you are not sure, have a qualiﬁ ed person

perform the installa on.

ConƟ nued on the next page...

Printed on: 7/6/2023 9:40:13 AM CT

Power Vented Ultra Low Nox Gas Water Heater - Use and Care Guide • 19

INSTALLATION

On the old water heater, turn

the control knob on the gas

control valve to the

OFF posi on.

Gas

control

knob

Figure 16 - 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 (This may take 10 min

utes or longer).

Figure 17 - Let the hot water run until 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. (Sedi-

ment in the bo om of the tank may

clog the valve and prevent it from

draining. If you can’t get the tank to

drain, contact a qualiﬁ ed person.)

Turn the cold water supply

valve OFF.

Figure 18 - Cold water supply in off position.

Using a standard ﬂ at-blade

screwdriver, open the drain

valve. Sediment build up in

the bo om of the water heater may

hinder or prevent draining.

Figure 19 - 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 20 - Removing the T&P Relief Valve

discharge pipe.

Allow the ven ng system to

cool. Once it is cooled,

disconnect the vent pipe from

the water heater. You may need to

support the vent pipe un l the new

water heater is in place.

Disconnect the water pipes.

Many water pipes are con-

nected 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.

Conﬁ 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.

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20 • Power Vented Ultra Low Nox Gas Water Heater - Use and Care Guide

INSTALLATION

Step 4:

✓

Installing the New

Water Heater

Read all instruc ons

completely 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 qualiﬁ ed person to install your

water heater.

• Call Technical Assistance at the tele-

phone number listed on your war-

ranty.

Install a metal drain pan that

is piped to an adequate drain.

6” Max.

Drain

Metal drain pan

piped to drain

Figure 21 - Metal drain pan piped to 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 dimen-

sions of the water heater (width and

depth) by at least 3 inches (76.2 mm)

in any direc on. If the water heater is

installed on carpet in an alcove or

closet, the en re ﬂ oor must be covered

by a wood or metal panel.

NOTICE: Most codes require se ng

the water heater in a metal drain pan

piped to an adequate drain. The drain

pan helps avoid property damage

which may occur from condensa on

or leaks in the piping connec ons or

tank. The drain pan must be at least

two inches wider than the diameter

of the water heater. Install the drain

pan so the water level is limited to a

maximum depth of 1-3/4”.

Verify that the water heater is

set in place properly. Check

that:

• There is adequate space to install

the T&P Relief Valve discharge

pipe and that it can be piped to a

separate drain (and not into the

drain pan).

• There is adequate access and

space around the water heater

for future maintenance.

• The water heater is installed ver -

cally.

Step 5:

Air Filter Inspec on

This water heater is equipped with a

base-ring air ﬁ lter. Before proceeding

to the next step, visually check the

ﬁ lter to ensure it is properly seated

in the base-ring. Do not operate the

water heater without the a clean air

ﬁ lter in place.

Printed on: 7/6/2023 9:40:13 AM CT

Power Vented Ultra Low Nox Gas Water Heater - Use and Care Guide • 21

INSTALLATION

Step 6:

✓

Connect the Tem-

perature and Pres-

sure (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 accord-

ing to local codes.

Figure 22 - Temperature and Pressure Relief

Valve

WARNING! To avoid serious injury

or death from explosion, install a T&P

Relief Valve according to the following

instruc ons:

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.

• The discharge pipe should be at

least 3/4” inside diameter and

sloped for proper drainage. Install

it to allow complete drainage of

both the T&P Relief Valve and the

discharge pipe.

Figure 23 - Temperature and Pressure Relief

Valve 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

(121°C) without distor on. Use

only copper or CPVC pipe. Do not

use any other type of pipe, such as

PVC, iron, ﬂ exible plas c pipe, or

any type of hose.

• Terminate the discharge pipe a

maximum of six inches above a

ﬂ 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 dis-

charge pipe inside the building to

an adequate drain. Outside drains

could freeze and obstruct the

drain line—protect the discharge

pipe from freezing.

• Do not place any valve or other

restric 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 discharge pipe. Do

not insert or install any reducer in

the discharge pipe.

Printed on: 7/6/2023 9:40:13 AM CT

22 • Power Vented Ultra Low Nox Gas Water Heater - Use and Care Guide

INSTALLATION

Step 7:

✓

Install Shutoﬀ and

Thermosta c

Mixing Valves

If one is not already installed,

install a manual shutoﬀ valve

in the cold water line that

supplies the water heater. Install the

shutoﬀ valve near the water heater so

that it is readily accessible. Only use a

full-ﬂ ow ball or gate valve compa ble

with potable water.

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.

Figure 24 - Install Thermostatic Mixing Valves at

each point where hot water will be used.

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.

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

severe injury or death.

Step 8:

Connect the Water

Supply

Note that all piping and components

connected to the water heater must

be suitable for use with potable water.

Determine the type of water

pipes in your home. Most

homes use copper water

pipes, but some use CPVC or cross-

linked polyethylene (PEX). Use ﬁ  ngs

appropriate for the type of pipe in

your home. Do not use iron or PVC

pipe.

Connect the cold water

supply using 3/4 inch

Na onal Pipe Thread “NPT” to the

ﬁ  ng marked “COLD”.

For ease of removing the water heater

for service or replacement, connect

the water pipes with a coupling called

a union. We recommend using a

dielectric-type union (available from

your local plumbing supplier). Dielec-

tric unions can help prevent corrosion

IF YOU HAVE COPPER PIPES:

If your home has copper water pipes,

you can solder the water pipe connec-

 ons or use compression ﬁ  ngs which

don’t require soldering. Compression

ﬁ  ngs are easier to install than solder-

ing pipe. Check with local plumbing

oﬃ cials to determine what types of

pipe materials are suitable for your

loca on. Do not use lead-based solder.

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 a

foot or so) to a threaded adapter using

only 95/5  n-an mony or equivalent

solder. A ach the threaded adapters

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.

Compression ﬁ  ngs don’t require soldering.

Printed on: 7/6/2023 9:40:13 AM CT

Power Vented Ultra Low Nox Gas Water Heater - Use and Care Guide • 23

INSTALLATION

caused by  ny electric currents com-

mon in copper water pipes and can help

extend the life of the water heater.

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 3/4 inch NPT to the

ﬁ  ng marked “HOT”.

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 eﬃ ciency.

Adjust (or install) the home’s

Pressure Reducing Valve to

50-60 psi and install a Thermal

Expansion Tank.

Figure 25 - A Pressure Reducing Valve is required

if your home’s water pressure is above 80 psi.

Figure 26 - The Thermal Expansion Tank should

be pressurized with air, using a hand pump, to

match the home’s incoming water pressure.

Step 9:

Verify Connec ons and

Completely Fill Tank

To remove air from the tank and allow

the tank to ﬁ ll completely with water,

follow these steps:

Remove the aerator at the

nearest hot water faucet. This

allows debris in plumbing

system to be washed out of the pipes.

Turn the cold water supply

back on and ﬁ ll the tank.

Open a hot water faucet and

allow the water to run un l it

ﬂ ows with a full stream.

Let the water run full stream

for three minutes.

Close the hot water faucet

and replace the aerator.

Check inlet and outlet connec-

 ons and water pipes for leaks.

Dry pipe connec ons so that

any drips or leaks will be apparent.

Repair any leaks. Almost all leaks occur

at connec ons and are not a tank leak.

Step 10:

Connect Vent Pipe to

Blower

Make sure your home’s ven ng system

complies with the instruc ons in this

manual and is in good condi on.

A 3”x 2” condensate drain coupler is

supplied to connect 2” venting to the

blower. The initial connection must

be made with 2” vent pipe. However,

after the initial connection, you may

use either 2” or 3” vent pipe. See

Figure 27. See also “Table 4: Vent Pipe

Lengths” on page 12

These connections must be properly

sealed to prevent the leakage of the

products of combustion into the living

area.

Before installing, clean and lightly sand

the end of the PVC/CPVC plas c vent

piping that will connect into the rubber

coupling. For polypropylene vent sys-

tems follow manufacturer’s instruc ons.

Polypropylene vent systems require

separate adaptor

NOTICE: Some installations may

require a condensate drain line. See

below.

2-Inch Vent Pipe

ŽŶŶĞĐƟŽŶ

Blower

2-Inch Vent

Pipe

Secure the vent

pipe and the

coupler to the

blower with

gear clamps.

Gear

Clamps

Condensate

Drain

Blower

Secure the vent

pipe and the

coupler to the

blower with

gear clamps.

3-Inch Vent Pipe

ŽŶŶĞĐƟŽŶ

Condensate

Drain

Gear

Clamps

3-Inch Vent

Pipe

Figure 27 - Vent Pipe/Blower Connection

INSTALLATION

Printed on: 7/6/2023 9:40:13 AM CT

24 • Power Vented Ultra Low Nox Gas Water Heater - Use and Care Guide

INSTALLATION

Condensate Drain:

Condensate forma on does not

occur in all installa ons of power

vented water heaters, but should

be drained on installa ons where it

can form in the ven ng system. The

vent pipe should be sloped upwards

away from the blower assembly, then

adequate means for draining and

disposing of the condensate needs to

be made by the installer. If installa on

condi ons cause condensa on, install

a condensate trap loop approximately

8”in diameter using 3/8” plas c hose.

Connect the hose to the built-in drain

port of the rubber coupling of the

blower assembly (see Figure 27).

Loop the hose in a ver cal posi on as

shown. The tube loop must be ﬁ lled

with water at least half way prior to

opera ng the heater. Ensure the end

of the tube has access to a drain as

condensate will ﬂ ow from the end.

Note: The removable cap must remain

in place if a drain hose is not installed.

Step 11:

Make Gas Connec ons

The Gas Water Heater Hook-Up Kit

(available at your local plumbing sup-

plier) includes a ﬂ exible gas connector

with compression ﬁ  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 ﬂ exible gas connector.

Figure 28 - Flexible gas line connector.

Once you’ve 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 ﬂ 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 oﬀ ,  ghten the leaking connec-

 on and re-check.

BEFORE LIGHTING THE WATER

HEATER...

Make sure all checklist items have

been completed.

Water Heater Loca on

✓ Installa on area free of corrosive

or ﬂ ammable materials, liquids or

vapors.

✓ Proper clearances from combus ble

surfaces maintained and suﬃ cient

room to service the water heater.

✓ Not installed directly on a carpeted

ﬂ oor.

✓ Metal drain pan installed and piped

to an adequate drain.

✓ Water heater not located near an

air moving device (fan, clothes

dryer).

✓ Not in a loca on with large

amounts of lint, dust, etc. (If so,

the air ﬁ lter or ﬂ ame arrestor

located on the bo om of the water

heater will need to be cleaned

more o en.)

Combus on Air Supply and

Ven la on

✓ Adequate air supply for water

heater and any other nearby gas

appliances.

If the water heater is installed in a

closet or other small, enclosed space

or within the living space of the

house, air supply openings needed.

✓ Are the openings of suﬃ cient size?

✓ Ductwork is the same cross-sec-

 onal area as the openings?

✓ Outside air openings are preferred

and may be required in  ghtly built

homes.

Printed on: 7/6/2023 9:40:13 AM CT

Power Vented Ultra Low Nox Gas Water Heater - Use and Care Guide • 25

INSTALLATION

✓ Sufficient fresh air supply for

proper water heater operation.

✓ Fresh air not taken from areas

that contain negative pressure

producing devices such as exhaust

fans, fireplaces, etc.

✓ Fresh air supply free of corrosive

elements and

flammable vapors.

✓ Fresh air openings sized correctly

with consideration given to the

blocking effect of louvers and

grilles.

✓ Ductwork is the same cross-

sectional area as the openings.

Vent Pipe System

✓ Vent pipe and fittings of approved

material.

✓ Acceptable size, length, and

number of elbows on

exhaust outlet pipe.

✓ Installed in accordance with

prevailing provisions of

local codes, or in the absence of

such, National Fuel Gas Code, NFPA

54, ANSI Z223.1-Current edition.

✓ Slope 2” & 3” horizontal piping at

a downward pitch of 1/8” per 5 ft.

away from the water heater.

✓ Not obstructed in any way.

NOTICE: Venting requirements are

listed in the “Venting” section on

page 11.

Vent Termination

Horizontal Vent Termination

✓ 12” Min. above grade/snow

level.

✓ Slope 2” & 3” horizontal

piping at a downward pitch of

1/8” per 5ft. away from the

water heater.

✓ Away from corners, other

vents, windows, etc.

Vertical Vent Termination

✓ Outlet - 12” Min. above roof/

snow level.

NOTICE: Vent termination

requirements are listed in the

“Vent Terminations” section on

page 13.

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 filled with

water.

✓ Thermal Expansion Tank installed

✓ Water Pressure Reducing Valve

installed and adjusted to 50-60 psi.

✓ Thermostatic 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 rating plate.

✓ Gas line equipped with shut-off

valve.

✓ Adequate gas pipe size and

approved gas pipe material.

✓ All gas connections and fittings leak

checked and any leaks corrected.

Electrical Connections

✓ Unit connected to a 120V electrical

supply. (Do not use an extension

cord.)

✓ A dedicated circuit is preferred.

✓ Proper polarity.

✓ Electrically grounded in accordance

with local codes, or in the absence

of such, the current edition of the

National Electric Code, ANSI/NFPA

70.

See page 38 for specific

information about the electrical

system.

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26 • Power Vented Ultra Low Nox Gas Water Heater - Use and Care Guide

INSTALLATION

For all side wall terminated, horizontally vented power vent, direct vent, and power direct vent gas fueled water heaters installed

in every dwelling, building or structure used in whole or in part for residential purposes, including those owned or operated by

the Commonwealth and where the side wall exhaust vent termination is less than seven (7) feet above ¿ nished grade in the

area of the venting, including but not limited to decks and porches, the following requirements shall be satis¿ ed:

INSTALLATION OF CARBON MONOXIDE DETECTORS At the time of installation of the side wall horizontal vented gas

fueled equipment, the installing plumber or gas¿ tter shall observe that a hard wired carbon monoxide detector with an alarm

and battery back-up is installed on the À oor level where the gas equipment is to be installed. In addition, the installing plumber

or gas¿ tter shall observe that a battery operated or hard wired carbon monoxide detector with an alarm is installed on each

additional level of the dwelling, building or structure served by the sidewall horizontal vented gas fueled equipment. It shall

be the responsibility of the property owner to secure the services of quali¿ ed licensed professionals for the installation of hard

wired carbon monoxide detectors.

In the event that the side wall horizontally vented gas fueled equipment is installed in a crawl space or an attic, the hard wired

carbon monoxide detector with alarm and battery back-up may be installed on the next adjacent À oor level.

In the event that the requirements of this subdivision can not be met at the time of completion of installation, the owner shall

have a period of thirty (30) days to comply with the above requirements provided that during said thirty (30) day period, a bat-

tery operated carbon monoxide detector with an alarm shall be installed.

APPROVED CARBON MONOXIDE DETECTORS Each carbon monoxide detector as required in accordance with the above

provisions shall comply with NFPA 720 and be ANSI/UL 2034 listed and CSA certi¿ ed.

SIGNAGE A metal or plastic identi¿ cation plate shall be permanently mounted to the exterior of the building at a minimum height

of eight (8) feet above grade directly in line with the exhaust vent terminal for the horizontally vented gas fueled heating appli-

ance or equipment. The sign shall read, in print size no less than one-half (1/2) inch in size, “GAS VENT DIRECTLY BELOW.

KEEP CLEAR OF ALL OBSTRUCTIONS.”

INSPECTION The state or local gas inspector of the side wall horizontally vented gas fueled equipment shall not approve the

installation unless, upon inspection, the inspector observes carbon monoxide detectors and signage installed in accordance

with the provisions of 248 CMR 5.08(2)(a) 1 through 4.

EXEMPTIONS: The following equipment is exempt from 248 CMR 5.08(2)(a)1 through 4:

1. The equipment listed in Chapter 10 entitled “Equipment Not Required To Be Vented” in the most current edition of NFPA 54

as adopted by the Board; and

2. Product Approved side wall horizontally vented gas fueled equipment installed in a room or structure separate from the

dwelling, building, or structure used in whole or in part for residential purposes.

MANUFACTURER REQUIREMENTS - GAS EQUIPMENT VENTING SYSTEM PROVIDED When the manufacturer of Product

Approved side wall horizontally vented gas equipment provides a venting system design or venting system components with

the equipment, the instructions provided by the manufacturer for installation of the equipment and the venting system shall

include:

1. Detailed instructions for the installation of the venting system design or the venting system components; and

2. A complete parts list for the venting system design or venting system.

MANUFACTURER REQUIREMENTS - GAS EQUIPMENT VENTING SYSTEM NOT PROVIDED When the manufacturer of

a Product Approved side wall horizontally vented gas fueled equipment does not provide the parts for venting the À ue gases,

but identi¿ es “special venting systems,” the following requirements shall be satis¿ ed by the manufacturer:

1. The referenced “special venting system” instructions shall be included with the appliance or equipment installation

instructions; and

2. The “special venting systems” shall be Product Approved by the Board, and the instructions for that system shall include a

parts list and detailed installation instructions.

A copy of all installation instructions for all Product Approved side wall horizontally vented gas fueled equipment, all venting

instructions, all parts lists for venting instructions, and/or all venting design instructions shall remain with the appliance or

equipment at the completion of the installation.

INSTALLATION REQUIREMENTS FOR THE COMMONWEALTH OF MASSACHUSETTS

INSTALLATION

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Power Vented Ultra Low Nox Gas Water Heater - Use and Care Guide • 27

OPERATION

Ligh ng Instruc ons

WARNING! Explosion Hazard –

• If you smell gas at any point during

this process, STOP! Turn oﬀ the

gas supply and follow the safety

steps on your water heater’s light-

ing label ( tled FOR YOUR SAFETY,

READ BEFORE LIGHTING).

• Replace viewport if glass is miss-

ing or damaged.

• Failure to do so can result in

death, explosion or ﬁ re.

WARNING! Electrical Shock Hazard –

• Disconnect electrical power to

the water heater if service is to

be performed.

• Failure to do so can result in

death or electrical shock.

Read and understand these direc ons

thoroughly before a emp ng put your

water heater into service. Make sure

the viewport is not missing or dam-

aged. Make sure the tank is completely

ﬁ lled with water before ligh ng and

ac va ng the water heater. Check

the ra ng 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

ra ng 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.

Follow these steps to light the water

heater:

Disconnect the water heater’s

power plug from the ground-

ed 110/120 volt power supply.

Make sure the manual gas

valve for the water heater’s

supply line is OFF.

See

Figure 29.

Figure 29 - Gas valve in “on” position

Set the thermostat to the

lowest se ng by turning the

knob to “VAC”. See Figure 30.

DO NOT try to light the burner by

hand.

Set the switch to the OFF

posi on.

Wait ﬁ ve minutes to clear out

any gas.

ON/OFF

SWITCH

70°F110°F120°F

130°F

140°F

150°F

155°F

TEMPERATURE SETTING DIAL

Figure 30 - Gas control valve.

Connect the water heater’s

power plug to a grounded

110/120 volt power supply.

Make sure the manual gas

valve for the water heater’s

supply line is ON.

See Figure 29.

Set the switch to the ON

posi on.

Set the thermostat to the

desired se ng

WARNING! Higher tem-

peratures increase the risk of scalding,

but even at 120°F, hot water can scald.

(See Table 1 on page 4.)

. Install

Thermosta c Mixing Valve(s) at each

point-of-use to reduce the risk of

scalding. The HOT on the gas control

valve indicates the preferred 120°F set

point.

IF the water heater will not

operate, follow these steps:

A. Set the thermostat to the lowest

se ng by turning the knob to

“VAC”. See Figure 30 - Gas control

valve.

B. Set the switch to the OFF posi on.

C. Unplug electrical service to the

water heater.

D. Turn off the gas at the manual gas

supply shutoff valve.

E. Call the technical assistance

hot line which is listed on your

warranty.

When a gas water heater is

ﬁ 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 ﬁ rst lit or, you may see a small

puddle on the ﬂ oor. Condensa on is not

a leak and will go away once the tank

reaches normal opera ng temperature.

The air ﬁ lter at the bo om of

the water heater must be

cleaned from  me to  me.

See the Maintenance sec on for steps

on cleaning the air ﬁ lter.

Shut down Instruc ons

A. Set the thermostat to the lowest

se ng by turning the knob to

“VAC”. See Figure 30.

B. Set the switch to the OFF posi on.

C. Disconnect the water heater’s

power plug from the grounded

110/120 volt power supply.

Emergency Shut down

Should overhea ng occur or the gas

supply fail to shut oﬀ , turn oﬀ the water

heater’s manual gas control valve and

call a qualiﬁ ed person.

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28 • Power Vented Ultra Low Nox Gas Water Heater - Use and Care Guide

OPERATION

NOTICE: This water heater is designed

to automa cally shut oﬀ in the event of

the following:

1. The water temperature exceeds

180°F (83°C.)

2. A blockage occurs in the combus-

 on chamber air inlet, the ﬂ ue gas

exhaust outlet, or both the inlet

and outlet.

3. The blower fails to operate or oper-

ates improperly.

4. The igni on of ﬂ ammable vapors.

A high temperature limit switch or ECO

(Energy Cut Oﬀ ) in the tank is used to

shut oﬀ the unit if the water tempera-

ture exceeds 180°F (83°C.)

Temperature Control

System

Adjus ng the Temperature

You may adjust the water heater’s

temperature se ng, if desired. Using

the lowest hot water temperature that

meets your needs will also provide

energy eﬃ cient opera on of the water

heater.

Set the gas valve to the desired

temperature. HOT on the gas

control valve/thermostat

indicates a set point of approximately

120°F, reducing the risk of scald injury.

It is the preferred star ng point for

se ng the temperature control.

You may wish to set a higher tempera-

ture 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 bacte-

ria that cause a condi on known as

“smelly water” and can reduce the

levels of bacteria that cause water-

borne diseases.

Water usage pa erns, as well as heat

from sources such as solar collectors

and ambient air can result in tempera-

tures higher than the thermostat set

point.

WARNING! Higher temperatures

increase the risk of scalding, but even

at 120°F, hot water can scald. (See

Table 1 on page 4.) Install Thermo-

sta c Mixing Valve(s) at each point-of-

use to reduce the risk of scalding.

To adjust the water heater’s

turn the temperature se ng

dial to the desired temperature.

ON/OFF

SWITCH

70°F110°F120°F

130°F

140°F

150°F

155°F

TEMPERATURE SETTING DIAL

Figure 31 - Temperature settings.

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 29).

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 ﬂ 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 not installed) you could

scald yourself while checking the

temperature.

Check water temperature at

several points of use in your

home (for example, bathtub

faucet, shower, or lavatory sink) and

adjust the Thermosta c Mixing Valves

as needed. If you aren’t sure how to

adjust the Thermosta c Mixing Valve

se ngs, or aren’t sure if you have

Thermosta c Mixing Valves, contact a

qualiﬁ ed person.

Opera ng Modes

The gas control valve has two diﬀ er-

ent opera ng modes: Standard and

Vaca on. The Standard mode allows

you to adjust the water temperature

to your desired se ng. The Vaca on

(WARM) mode sets the thermostat at

approximately 70°F and is recommend-

ed when not using hot water for an

extended period of  me. The WARM

se ng also reduces energy losses and

keeps the tank from freezing during

cold weather but can cause a hydrogen

gas build up. See warning regarding

hydrogen gas on page 5.

OPERATION

Printed on: 7/6/2023 9:40:13 AM CT

Power Vented Ultra Low Nox Gas Water Heater - Use and Care Guide • 29

TROUBLESHOOTING

NOTICE

If the LEDs on your gas control valve/

thermostat indicate an error code, refer

to the chart on pages 32.

Water Heater

Opera on

The figure below shows the water

heater’s sequence of operation when

a call for heat is initiated. (This is

when the water heater begins to

heat water based on the thermostat

setting.) The ignition control will try

to light the burner three times. If

the ignition control does not detect

ignition, it will enter lock-out mode,

indicated by a three flash error code.

^ĞƋƵĞŶĐĞŽĨKƉĞƌĂƟŽŶ

Heater control checks to ensure blower

pressure switch is open.

Blower is energized.

Control checks to ensure pressure switch

ĐůŽƐĞƐŝŶĚŝĐĂƟŶŐďůŽǁĞƌŝƐŽƉĞƌĂƟŶŐĂŶĚ

ƚŚĞƌĞĂƌĞŶŽǀĞŶƟŶŐďůŽĐŬĂŐĞƐ

(inlet or outlet).

Igniter is energized and

main gas valve is opened.

Main burner comes on and the

ŇĂŵĞŝƐƐĞŶƐĞĚďǇĐŽŶƚƌŽů

DĂŝŶďƵƌŶĞƌĐŽŶƟŶƵĞƐƟůůƚŚĞǁĂƚĞƌŝŶƚŚĞ

ƚĂŶŬƌĞĂĐŚĞƐƚŚĞƌŵŽƐƚĂƚƐĞƫŶŐ

DĂŝŶďƵƌŶĞƌƐŚƵƚƐŽīůŽǁĞƌĐŽŶƟŶƵĞƐĨŽƌ

ĂƉŽƐƚƉƵƌŐĞƟŵĞ

Heater

thermostat

calls for

heat.

Heater

remains on

ƐƚĂŶĚďǇ

ƵŶƟůŶĞǆƚ

call for

heat.

Figure 32 - Sequence of Operation

No Hot Water

If your water heater is not producing

hot water, refer to “TROUBLESHOOT-

ING” on page 29.

Insuﬃ cient Hot Water

or Slow Hot Water

Recovery

WARNING! Because of the in-

creased risk from scalding, if you set

the water heater’s gas control knob

higher than 120°F, install Thermosta c

Mixing Valves at each point-of-use.

Due to the increased risk of scalding,

do not set the temperature of the

Thermosta c Mixing Valves above

120°F.

If the hot water is simply not warm

enough, there are several possible

causes:

• Faulty Thermosta c Mixing Valve

in a faucet or shower control

(check other faucets in the house

for hot water).

• Water heater’s capacity too small

(or usage too high).

• Reversed plumbing connec ons

or melted dip tube (usually found

soon a er new installa on).

• Plumbing leak.

• Sediment or lime build up in the

bo om of the tank.

• Defec ve thermostat or ECO

(energy cut-oﬀ switch)

• For other poten al causes, refer

to “TROUBLESHOOTING” on page

29.

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, con-

sider replacing it with a larger model. If

the water heater is in good condi on,

you may be able to meet your fam-

ily’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 ﬂ 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

is melted, the nipple dip tube assem-

bly can be removed, and replaced

with a new one.

Plumbing Leak. Even a small leak

in the hot water side of the home’s

plumbing system can make it appear

that the water heater is producing

li le to no hot water. In this case, the

burner will be on all or almost all the

Printed on: 7/6/2023 9:40:13 AM CT

30 • Power Vented Ultra Low Nox Gas Water Heater - Use and Care Guide

TROUBLESHOOTING

 me, yet you will have very li le hot

water. Locate and repair the leak.

Sediment or Lime in Tank. With an ex-

is ng water heater, if you have some

hot water but not as much as you’re

used to, there may be a build up of

sediment or lime on the bo om of the

tank. Sediment or lime build up can

reduce the eﬃ ciency of your water

heater. Heavy deposits can damage

the water heater. See the Mainte-

nance sec on for steps on draining

and ﬂ ushing the water heater.

Failure of the thermostat or ECO

(energy cut-oﬀ switch). If either

component failed, the water will not

be heated as expected. Replace the

thermostat/ECO as required.

Temperature Too High

Adjust the thermostat on the water

heater to a lower se ng. Install or

adjust Thermosta c Mixing Valves

for 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 ﬂ ow of hot water.

If that’s 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 Expan-

sion Tank. See page 16 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 oﬀ and call a quali-

ﬁ 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 Re-

ducing 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 Ex-

pansion 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, prevent-

ing the valve from sealing 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

ﬂ ush out the debris. See the label on

the T&P Relief Valve for instruc ons.

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, but it s ll drips, the valve may

be broken. Have a qualiﬁ ed person

replace the T&P Relief Valve.

Water Odor

Harmless bacteria normally present in

tap water can mul ply in water heat-

ers and give oﬀ a “ro en egg” smell.

Although elimina ng the bacteria that

causes “smelly water” is the only sure

treatment, in some cases, the stan-

dard 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 qualiﬁ 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 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.

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Power Vented Ultra Low Nox Gas Water Heater - Use and Care Guide • 31

TROUBLESHOOTING

These guidelines should be utilized by a qualiﬁ ed service agent.

LOCKOUTS

So Lockout

• • Occurs when a system safety device trips to break the

sequence of operation. The control will try to start the system in

a timed basis but will not reinstate operation until the failure is

corrected.

Hard Lockout

• Occurs when the main controller fails and must be replaced.

RESETTING THE HEATER CONTROL

• Soft lockouts as diagnosed by the system error codes require

the gas control to be reset.

• To reset the control, slide the “ON/OFF” switch to the “OFF”

position. Wait for 10 seconds and move the switch back to the

“ON” position.

• If the problem that caused the control to lock out has not been

corrected, the control will remain locked out, or again go into

lock out.

IGNITION STATE TIMING

Pre-purge 5 Seconds

Hot Surface igniter (HSI) Warm-up 10 Seconds

Ignition Activation Period (IAP) 3.5 Seconds

Flame Recognition Period (FRP) 0.5 Seconds

Trial For Ignition IAP + FRP

Purge when flame not sensed. 30 seconds

Flame Failure

Response Time

2 seconds max

(@ 1uA flame current)

Post-purge 30 seconds

Pressure Switch (PS)

Prove Period

2 minutes

Pressure Switch (PS)

Fault Delay (failed

open/closed)

2 minutes

Soft Lockout 20 minutes (Ignition reattempt)

Energy Cut Off

(ECO) Limit Lockout

Indefinite (clear fault to restart in 15

seconds or less)

Flammable Vapor (FV) Sensor

Lockout

Indefinite (see “Resetting The Heater

Control”)

Soo ng

Is the result of improper combustion.

Check venting to ensure no blockages

are present. Confirm all exhaust piping

is properly sized, see “Combustion

and Ventilation Air Supply” section on

page 7. A wrong gas type may also

cause sooting, see ”Gas Piping” on

page 15.

Heater Lights But Goes

out in 4-5 Seconds

Make sure the correct vent restrictor

is installed. Follow the instructions in

the “Venting” section on page 11. If

the issue continues have a qualified

person check the outlet polarity.

Improperly sized gas piping may also

cause this issue, see ”Gas Piping” on

page 15.

Hot Surface Igniter

Not Glowing Following

Warm-Up Period

The hot surface igniter should glow

when during the warm-up period if it

fails to do so follow the instructions

on page 27-28 to turn off your water

heater and contact a qualified person

to check the system.

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32 • Power Vented Ultra Low Nox Gas Water Heater - Use and Care Guide

TROUBLESHOOTING

SYSTEM STATUS AND ERROR CODES

The micro-controller inside the gas control monitors the ignition sequence, temperature settings, and overall operation of

the heater. If any of these parameters does not operate properly the controller will shut down the water heater, diagnose

the failure and ﬂ ash an error code. The table below lists the System Status Codes for the Honeywell control. Refer to it

and to the “Ignition State And Timing” to diagnose the problem before attempting corrective action.

ERROR CODES

LED Flash Sequence Control Status

Corrective

Action Number

Short flash

once every four seconds

IDLE (no call for heat,

no fault conditions)

“Heartbeat”,

alternates bright/dim

Call For Heat

(no fault conditions)

One Flash,

three second pause

Low Flame Signal

(control continues to operate)

Two Flash,

three second pause

Pressure Switch Failed Closed 4

Three Flash,

three second pause

Pressure Switch Failed Open 5

Four Flash,

three second pause

ECO (Energy Cut Off) Limit Lockout

thermostat temperature limit was exceeded.

Five Flash,

three second pause

Flame Out Of Sequence 7

Six-One Flash,

three second pause

Soft Lockout

- Retry Limit

- Failed Trial For Ignition

Six-Two Flash,

three second pause

Soft Lockout

- Recycle Limit

- Pressure Switch/High Limit opened

Six-Three Flash,

three second pause

Soft Lockout

- Recycle Limit

- Flame Lost

Six-Four Flash, three second pause

Soft Lockout

- Flame out of Sequence Sensed

Seven Flash,

three second pause

Flammable Vapor Sensor (FVS) Lockout 12

Eight-One Flash,

three second pause

Flammable Vapor Sensor FVS Fault Detected 13

Eight-Two Flash,

three second pause

Temperature Sensor Fault Detected 14

Eight-Three Flash,

three second pause

Electronics Fault Detected 15

Eight-Four Flash,

three second pause

Valve Fault Detected 16

Hardware Fault Lockout Indefinite 17

READING THE LED FLASH SEQUENCE.

The LED indicator light is active when the gas valve/thermostat is in operation. The light will normally show a flash sequence of a short flash once every four seconds

or a “Heartbeat” of alternating bright/dim. Multiple flash codes indicate an error and can be read as follows: Example: Corrective Action Number 9, Six-Two Flash, three

second pause. For this code, the LED indicator light will make six bright flashes, pause for one second and then make two more bright flashes. The LED will pause for

three seconds and repeat the six-two cycle of flashes.

Printed on: 7/6/2023 9:40:13 AM CT

Power Vented Ultra Low Nox Gas Water Heater - Use and Care Guide • 33

TROUBLESHOOTING

CORRECTIVE ACTIONS

See the table below for corrective actions corresponding to the Corrective Action Number in the “System Status And Error Codes” section above. If following those

corrective actions does not resolve the error, refer to “Other Symptoms” table later in this manual.

Corrective

Action

Number

Corrective Action

1 Normal operation, no action necessary.

2 Normal operation, no action necessary.

3 1. Flame rod not properly seated in flame, reposition rod.

2. Clean flame sensor rod with fine steel wood to remove any buildup which may prevent flame sensing

4 1. Check that blower operates and does not have any blockages.

2. Check that all wiring is correct.

3. Ensure the air pressure sensing tubes are properly connected and not kinked or damaged.

4. Ensure the air pressure switch is correct and the air pressure switch (N.O.) is not bypassed (jumpered).

5. Turn power to the unit “OFF” – check for continuity of the air pressure switch (N.O.) with wires disconnected;

a. If the pressure switch contacts show continuity (closed circuit), replace the pressure switch,

b. If the pressure switch contacts are open and all wiring is correct, replace the Gas Control.

5 1. If the blower does not run after resetting the heater, check for 120 VAC to the blower when the heating cycle begins.

a. If the Gas Control does not energize the blower - replace the Gas Control.

b. If the blower fails to start when energized:

i. Turn power to the heater “OFF” – check if the capacitor is connected;

ii. Turn power to the heater “OFF” – check the capacitor rating (3uF +/-5%);

iii. Turn power to the heater “OFF” - replace the blower assembly.

2. Ensure the air pressure sensing tubes are properly connected and not kinked or damaged;

3. Check continuity of the vent temperature limit switch – replace switch if contact remain open.

4. With the blower running, check continuity of the air pressure switch (N.C.) – replace switch if contact remain open.

5. Ensure the correct size of exhaust and air intake pipes were used per the instruction manual for vent length. Ensure maximum number of

elbows or equivalent feet of both pipes was not exceeded.

6. Ensure there are no obstructions in the exhaust and air intake pipes.

7. If there are excessive restrictions in the air intake pipe the air pressure switch (N.C.) will open.

8. Check air pressure switch performance - Check blower vacuum with a manometer - Compare with air pressure switch (N.O.) setting. If the

air pressure switch proves defective – replace the air pressure switch (N.O.).

9. If the air pressure switch (N.O.) performance test results prove the air pressure switch is working properly, and all other steps are followed,

and fault code persist – replace the control.

6 Resetting the ECO (Energy Cut-Out) requires manual intervention. It cannot be reset by cycling power to the control.

Reset Procedure:

1. Manual reset is performed by turning the set point knob to lowest set point position for a minimum of 10 seconds and then return it to the

desired set point.

2. The manual reset of the ECO can only be performed 2 times, after the ECO trips a third time, the gas valve will enter a hard lock out where

the gas control will need to be replaced.

7 1. Turn the power “OFF” for 10-20 seconds then “ON” again to clear the fault code.

2. Clean flame sensor rod with fine steel wool to remove any buildup which may prevent flame sensing.

3. Flame rod not properly seated in flame, reposition rod.

4. Replace the control if the fault code persists.

8 1. Gas supply is turned off or gas pressure is too low. Ensure supply pressure and manifold gas pressures are within requirements. Manifold

pressure is nonadjustable, if gas supply pressure proves correct and manifold pressure is off by more than 0.3” WC replace the control.

2. Low supply voltage - should be 115 - 125 VAC

3. Ensure flame sensor is making good contact with the burner flame and flame is steady.

4. Ensure flame sensor is clean, use ultra- fine steel wool to clean flame sensor.

5. Ensure the Hot Surface Igniter is positioned properly to provide consistent ignition.

6. Check for any cracks in igniter assembly ceramic insulators - replace igniter assembly if damaged.

7. Check resistance of igniter at room temperature (at the plug). Replace the igniter if resistance is not within 42-76 ohms at room

temperature.

8. Ensure correct size of exhaust and air intake pipes were used per the instruction manual for vent length. Ensure maximum number of

elbows or equivalent feet of both pipes was not exceeded.

TROUBLESHOOTING

Printed on: 7/6/2023 9:40:13 AM CT

34 • Power Vented Ultra Low Nox Gas Water Heater - Use and Care Guide

TROUBLESHOOTING

Corrective

Action

Number

Corrective Action

9 1. If the blower does not run after resetting the heater, check for 120 VAC to the blower when the heating cycle begins.

a. If the Gas Control does not energize the blower - replace the Gas Control.

b. If the blower fails to start when energized:

i. Turn power to the unit “OFF” – check if the capacitor is connected;

ii. Turn power to the unit “OFF” – check the capacitor rating (3uF +/-5%);

iii. Turn power to the unit “OFF” - replace the blower assembly.

2. Ensure the air pressure sensing tubes are properly connected and not kinked or damaged;

3. Check continuity of the vent temperature limit switch – replace switch if contacts remain open.

4. With the blower running, check continuity of the air pressure switch (N.C.) – replace switch if contact remain open.

5. Check continuity of the High Limit switch (N.C.) – replace switch if contact remain open.

6. Ensure correct size of exhaust and air intake pipes were used per the instruction manual for vent length. Ensure maximum number of

elbows or equivalent feet of both pipes was not exceeded.

7. Ensure there are no obstructions in the exhaust and air intake pipes.

8. If there are excessive restrictions in the air intake pipe the air pressure switch (N.C.) will open.

9. Check air pressure switch performance - Check blower vacuum with a manometer - Compare with air pressure switch (N.O.) setting. If the

air pressure switch proves defective – replace the air pressure switch (N.O.).

10. If the air pressure switch (N.O.) performance test results prove the air pressure switch is working properly, and all other steps are followed,

and fault code persist – replace the gas control valve.

10 1. Gas supply is turned “OFF” or gas pressure is too low. Ensure supply pressure and manifold gas pressures are within requirements.

Manifold pressure is nonadjustable. If supply pressure proves correct and manifold, pressure is off by more than 0.3” WC replace the

control.

2. Low supply voltage - should be 115 - 125 VAC

3. Ensure flame sensor is making good contact with the burner flame and flame is steady.

4. Ensure the flame sensor is clean, use ultra-fine steel wool to clean flame sensor.

5. Ensure the Hot Surface Igniter is positioned properly to provide consistent ignition.

6. Check for any cracks in igniter assembly ceramic insulators - replace igniter assembly if damaged.

7. Check resistance of igniter at room temperature (at the plug). Replace the igniter if resistance is not within 42-76 ohms at room

temperature.

8. Ensure correct size of exhaust and air intake pipes were used per the instruction manual for vent length. Ensure maximum number of

elbows or equivalent feet of both pipes was not exceeded.

9. Ensure vent termination restrictor/fitting is installed, and is correct in accordance with venting tables.

11 1. Turn the power “OFF” for 10-20 seconds then “ON” again to clear the fault code.

2. Replace the gas control valve if fault code persists.

12 1. Flammable vapor sensed indicates the presence of flammable vapors, or other chemicals which have activated the flammable vapor sensor.

Ensure no flammable vapors, chemicals or littler boxes which release ammonia are near the water heater, and replace the flammable vapor

sensor. Once replaced, reset the control using the “RESETTING THE HEATER CONTROL” procedure on page 31.

13 1. Flammable Vapor Sensor (FVS) Fault Detected means the signal to and from the FVS has been interrupted, or the FVS has been jumped/

bypassed. Physical damage including exposure to water will damage the FVS, requiring replacement. If the FVS has not been exposed to

water, and is not damaged, ensure the FVS connections are secure. If fault continues, replace the FVS. Once replaced, reset the control

using the “RESETTING THE HEATER CONTROL” procedure on page 31.

14 1. Turn the power “OFF” for 10-20 seconds then “ON” again to clear the fault code.

2. Replace the control if the fault code persist.

15 1. Turn the power “OFF” for 10-20 seconds then “ON” again to clear the fault code.

2. Replace the control if the fault code persist.

16 1. Turn the power “OFF” for 10-20 seconds then “ON” again to clear the fault code.

2. Replace the control if the fault code persist.

17 1. Control has failed. If resetting the control does not clear the fault code, replace the control.

TROUBLESHOOTING

Printed on: 7/6/2023 9:40:13 AM CT

Power Vented Ultra Low Nox Gas Water Heater - Use and Care Guide • 35

REPAIR PARTS

MAINTENANCE

Rou ne Maintenance

Rou ne maintenance will help your

water heater last longer and work bet-

ter. If you can’t perform these rou ne

maintenance tasks yourself, contact a

qualiﬁ ed person.

Draining and Flushing the Water

Heater

Tap water contains minerals that can

form sediment in the bo om of the

tank. The amount of sediment formed

depends on the hardness of your

tap water, the temperature se ngs,

and other variables. We recommend

draining and ﬂ ushing the water heater

a er the ﬁ rst six months of opera on

to determine the amount of sediment

build up. If there is li le sediment, drain

and ﬂ ush the tank annually. If there is a

lot of sediment, drain and ﬂ ush the tank

more o en. Draining sediment extends

the life of the water heater.

To Drain and Flush the Tank:

Turn off the gas to the water

heater at the manual gas

supply shut-off valve. (See

Figure 40 on page 37.)

Turn oﬀ the electrical supply to

the water heater.

Open a hot water faucet and

let the hot water run un l it is

cool. This may take 10 minutes

or longer.

Figure 33 - Let the hot water run until 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. Note that

sediment in the bo om of the tank may

clog the valve and prevent it from

draining. If you can’t get the tank to

drain, contact a qualiﬁ ed person.

Turn the cold water supply

valve OFF.

Open the drain valve on the

water heater.

Figure 34 - Draining the water heater.

Open a hot water faucet to

help the water in the tank

drain faster.

Remove and inspect the anode

rod and replace if depleted.

The anode rod requires a

1-1/16” socket.

Figure 35 - Anode rods from new (top) to par-

tially depleted (middle) to fully depleted stage

(bottom).

Anode Rod. The anode rod is a sacriﬁ -

cial metal rod that helps avoid corrosion

and premature failure (leaks) in the

tank. The anode rod is a consumable

item. Inspect the anode rod a er the

ﬁ rst six months of opera on when you

drain and ﬂ 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 if

it is depleted. Obtain a new anode rod

or have a qualiﬁ ed person replace it.

(Anode rods are a consumable item and

are not covered under warranty.)

If a large amount of sediment

was present when the tank

was drained, ﬂ 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.

Printed on: 7/6/2023 9:40:13 AM CT

36 • Power Vented Ultra Low Nox Gas Water Heater - Use and Care Guide

MAINTENANCE

Reﬁ 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.

Put the water heater into

service using the instruc ons

on page 27 and set the

thermostat to the desired tempera-

ture. It may take an hour or more for

the tank of cold water to heat up.

Visual Inspec on

On an annual basis, visually inspect the

ven ng and air supply system, piping

systems, main burner, ﬂ ame sense rod,

and air ﬁ lter.

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 obstruct-

ed. Check the air ﬁ lter for dust or

other debris and clean if needed.

• Build up of soot and carbon on the

main burner and ﬂ ame sense rod.

The burner may be cleaned with

soap and hot water. The ﬂ ame

sense rod on the hot surface igniter

assembly may be cleaned with steel

wool.

• Inspect the burner flames through

the viewport and compare them

to Figure 36 - Burner Flames.

Flames should be very small with

a blue haze and small amounts

of yellow or orange at the edges.

After several minutes of operation,

the burner screen may glow red.

If large flames are observed at any

time, shut-off unit and call a quali-

fied person.

Correct flame

soft blue

Figure 36 - Burner Flames

• Leaking or damaged water and gas

piping.

• Remove any ﬂ ammable, corrosive

or combus ble materials near the

water heater.

If you lack the necessary skills required

to properly perform this visual inspec-

 on or if the burner and/or hot surface

igniter assembly need to be cleaned, get

help from a qualiﬁ ed person.

T&P Relief Valve Maintenance

Figure 37 - T&P Relief Valve.

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). 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, operate the T&P

Relief Valve manually to ensure the

waterways are clear and the valve

mechanism moves freely (above).

Before opera ng the valve manually,

check that it will discharge in a place

for secure disposal.

WARNING! Hot water will be

released. Before opera ng the T&P

relief valve manually, check that it will

discharge in a safe place. If water does

not ﬂ ow freely from the end of the

discharge pipe, turn the gas control

knob to the OFF posi on and call a

qualiﬁ ed person to determine the

cause.

• At least every ﬁ ve years, have a

qualiﬁ ed person inspect the T&P

Relief Valve and discharge pipe.

Damage caused by corrosive water

condi ons, mineral deposits, or

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