A. O. Smith BTF-80 Installation Manual

MODEL BTF-80

COMMERCIAL POWER VENT GAS WATER HEATER

with Hot Surface Ignition

Thank you for buying this energy efficient water heater.

We appreciate your condence in our products.

You should thoroughly read this manual before installation and/

or operation of this water heater. Please pay particular attention

to the important safety and operating instructions as well as the
WARNINGS and CAUTIONS.

TABLE OF CONTENTS

PAGE

GET TO KNOW YOUR WATER HEATER 2-3

GENERAL SAFETY INFORMATION 4-5

INSTALLATION 5-14

OPERATION 14-16

MAINTENANCE AND
TROUBLESHOOTING 16-19

TROUBLESHOOTING WITH THE LEDs 20

WARRANTY 24

CAUTION

TE X T P R I NTE D O R O U T L INE D I N R E D C O NTA I N S

INFO RMATI ON REL ATIVE TO YOUR SAFETY. PLEASE
READ THOROUGHLY BEFORE INSTALLING AND USING

THIS APPLIANCE.

KEEP THIS MANUAL IN THE POCKET ON THE HEATER FOR FUTURE REFERENCE

WHENEVER MAINTENANCE ADJUSTMENT OR SERVICE IS REQUIRED.

PRINTED IN U.S.A. 0406 PART NO. 197440-000

1

ROUGH-IN-DIMENSIONS

TOP VIEW

RECOVERY CAPACITIES

Recovery capacity based on 80% thermal efciency.

FOREWORD

The design of model BTF-80 complies with the current version
of ANSI Z21.10.3/CSA 4.3 as automatic storage or automatic

circulating tank type water heaters.

Installation diagrams are found in this manual. These diagrams
will serve to provide the installer with a reference for the
materials and method of piping necessary. It is highly essential
that all water and gas piping be installed as shown on the
diagrams.

In addition to these instructions, the equipment shall be installed
in accordance with those installation regulations in force in the
local area where the installation is to be made. These shall be

carefully followed in all cases. Authorities having jurisdiction
should be consulted before installations are made.

The installation must conform to these instructions and the local
code authority having jurisdiction. In the absence of local codes, the
installation must comply with the current editions of the National
Fuel Gas Code, ANSI Z223.1/NFPA 54 and the National Electrical
Code, NFPA 70 or CAN/CSA-B149.1, the Natural Gas and Propane
Installation Code and CSA C22.1, the Canadian Electrical Code.
All documents are available from the Canadian Standards
Association, 8501 East Pleasant Valley Road, Cleveland, OH

44131. NFPA documents are also available from the National Fire
Protection Association, 1 Batterymarch Park, Quincy, MA 02269.

2

GET TO KNOW YOUR WATER HEATER

REPLACEMENT PARTS AND DELIMING PRODUCTS

Replacement parts and recommended delimer may be ordered
through authorized servicers or distributors. Refer to the Yellow
Pages for where to call or contact the water heater manufacturer
at, 500 Tennessee Waltz Parkway, Ashland City, TN 37015. When
ordering parts, provide complete model and serial numbers (see
rating plate), quantity and name of part desired (as listed in Figure

1). Standard hardware items may be purchased locally.

(A) VENT PIPE
(B) ANODE
(C) HOT WATER OUTLET
(D) OUTLET (120 VAC)
(E) FLUE BAFFLE
(F) GAS SUPPLY
(G) MAIN MANUAL GAS
SHUT OFF VALVE
(H) GROUND JOINT UNION
(J) DIRT LEG
(K) OUTER DOOR
(L) UNION
(M) INLET WATER SHUT
OFF VALVE
(N) COLD WATER INLET

(O) INLET DIP TUBE
(P) TEMPERATURE AND
PRESSURE RELIEF VALVE
(Q) RATING PLATE
(R) INSULATION
(S) VENT TERMINAL
(T) DRAIN VALVE
(U) IGNITER AND MAIN
BURNER
(V) FLUE
(W) DRAIN PAN
(X) CONTROL
(Y) CONTROL HARNESS*
(Z) MOTOR & BLOWER
(AA) CONDENSATE FITTING

*CAUTION HARNESS HAS 115 VAC. IN OPERATION

TEMPERATURE INDICATORS

VACUUM RELIEF

VALVE

*INSTALL PER

LOCAL CODES

TEMPERATURE ADJUSTMENT BUTTONS

(U) NATURAL GAS MAIN BURNER

WITH IGNITER ASSEMBLY

(U) PROPANE GAS MAIN BURNER

WITH IGNITER ASSEMBLY

(SIDE VIEW)

FIGURE 1

3

GENERAL SAFETY INFORMATION

EXTERNAL DAMAGE

Do not operate the water heater until it has been fully checked out
by a qualied technician, if the water heater:

• Has been exposed to re or damage.

• Displays evidence of sooting.

• Produces steam or unusually hot water.

If the water heater has been subject to ooding it must be
replaced.

CHEMICAL VAPOR CORROSION

WARNING

CORROSION OF THE FLUEWAYS AND VENT SYSTEM MAY
OCCUR IF AIR FOR COMBUSTION CONTAINS CERTAIN
CHEMICAL VAPORS. SUCH CORROSION MAY RESULT IN
FAILURE AND RISK OF ASPHYXIATION.

Spray can propellants, cleaning solvents, refrigerator and air
conditioning refrigerants, swimming pool chemicals, calcium and
sodium chloride (water softener salt), waxes, and process chemicals
are typical compounds which are potentially corrosive.

Do not store products of this sort near the heater. Also, air
which is brought in contact with the heater should not contain
any of these chemicals. If necessary, uncontaminated air
should be obtained from remote or outside sources. The
limited warranty is voided when failure of water heater is due
to a corrosive atmosphere. (See limited warranty for complete
terms and conditions).

LP gas must be used with great caution. It is highly explosive
and heavier than air. It collects rst in the low areas making its
odor difcult to detect at nose level. If LP gas is present or even
suspected, do not attempt to nd the cause yourself. Go to a
neighbor's house, leaving your doors open to ventilate the house,
then call your gas supplier or service agent. Keep area clear until
a service call has been made.

At times you may not be able to smell an LP gas leak. One cause
is odor fade, which is a loss of the chemical odorant that gives
LP gas its distinctive smell. Another cause can be your physical
condition, such as having a cold or a diminishing sense of smell
with age. For these reasons, the use of a propane gas detector
is recommended.

IF YOU EXPERIENCE AN OUT-OF-GAS SITUATION, DO
NOT TRY TO RELIGHT APPLIANCES YOURSELF. Ask your
LP delivery person to relight pilots for you. Only trained LP
professionals should conduct the required safety checks in
accordance with industry standards.

EXTENDED NON-USE PERIODS

WARNING

HYDROGEN GAS CAN BE PRODUCED IN A HOT WATER

SYSTEM SERVED BY THIS HEATER THAT HAS NOT BEEN

USED FOR A LONG PERIOD OF TIME (GENERALLY TWO
WEEKS OR MORE). HYDROGEN GAS IS EXTREMELY

FLAMMABLE. To reduce the risk of injury under these conditions,

it is recommended that the hot water faucet be opened for several
minutes at the kitchen sink before using any electrical appliance
connected to the hot water system. If hydrogen is present, there
will probably be an unusual sound such as air escaping through
the pipe as the water begins to ow. THERE SHOULD BE NO

SMOKING OR OPEN FLAME NEAR THE FAUCET AT THE TIME

IT IS OPEN.

IMPROPER COMBUSTION

WARNING

ATTIC AN D/O R EX HAU ST FANS OPERATIN G ON THE
PREMISES WITH A WATER HEATER CAN RESULT IN CARBON

MONOXIDE POISONING AND DEATH.

OPERATION OF THESE FANS CAN PRODUCE A NEGATIVE

DRAFT IN THE AREA OF THE WATER HEATER PREVENTING

THE PRODUCTS OF COMBUSTION FROM EXHAUSTING

THROUGH THE VENT PIPE.

The venting of the water heater should be inspected by a qualied
service technician at the time of installation and periodically
thereafter to ensure a down-draft condition does not exist.

DO NOT OBSTRUCT THE FLOW OF COMBUSTION AND
VENTILATING AIR. ADEQUATE AIR FOR COMBUSTION AND

VENTILATION MUST BE PROVIDED FOR SAFE OPERATION.

LIQUID PETROLEUM MODELS

WARNING

Water heaters for propane or liqueed petroleum gas (LPG) are
different from natural gas models. A natural gas heater will not
function safely on LP gas and no attempt should be made to
convert a heater from natural gas to LP gas.

INSULATION BLANKETS

Insulation blankets available to the general public for external
use on gas water heaters are not necessary with this product.
The purpose of an insulation blanket is to reduce the standby
heat loss encountered with storage tank heaters. Your water
heater meets and exceeds the Energy Policy Act with respect to
insulation and standby loss requirements, making an insulation

blanket unnecessary.

WARNING

Should you choose to apply an insulation blanket to this
heater, you should follow these instructions (See Figure 1 for
identication of components mentioned below). Failure to follow
these instructions can restrict the air ow required for proper
combustion, potentially resulting in re, asphyxiation, serious
personal injury or death.

• Do not cover the gas valve or temperature & pressure relief
valve.

• Do not allow insulation to come within 2" (5.1 cm) of the dilution
air inlet on the blower, to prevent blockage of the dilution air.

• Do not allow insulation to come within 2" (5.1 cm) of the oor
to prevent blockage of combustion air ow to the burner.

4

• Do not cover the instruction manual. Keep it on the side of the
water heater or nearby for future reference.

• Do obtain new warning and instruction labels for placement
on the blanket directly over the existing labels.

• Do inspect the insulation blanket frequently to make certain it
does not sag, thereby obstructing combustion air ow.

sides and rear, 5.5" (14 cm) from the front and 12" (30 cm) from
the top. (Standard clearance.) If clearances stated on the heater
differ from standard clearances, install water heater according to
clearances stated on heater.

A minimum clearance of 4" (10 cm) must be allowed for access
to replaceable parts such as the thermostats, drain valve and
relief valve. A top clearance of 24" (61 cm) should be allowed for
blower assembly service.

INSTALLATION

REQUIRED ABILITY

INSTALLATION OR SERVICE OF THIS WATER HEATER REQUIRES
ABILITY EQUIVALENT TO THAT OF A LICENSED TRADESMAN IN
THE FIELD INVOLVED. PLUMBING, ELECTRICAL, AIR SUPPLY,
VENTING AND GAS SUPPLY ARE REQUIRED.

GENERAL

MAKE SURE that the gas supply where this water heater will be
installed is the same as that stated on its model and rating plate.

The installation must conform with these instructions and the local
code authority having jurisdiction. In the absence of local codes,
installations shall comply with the National Fuel Gas Code, ANSI
Z223.1/NFPA 54 and the National Electrical Code, NFPA 70 or
CAN/CSA-B149.1, the Natural Gas and Propane Installation Code
and CSA C22.1, the Canadian Electrical Code. All documents are
available from the Canadian Standards Association, 8501 East
Pleasant Valley Road, Cleveland, OH 44131. NFPA documents
are also available from the National Fire Protection Association,
1 Batterymarch Park, Quincy, MA 02269.

GROUNDING

The water heater when installed must be grounded in accordance with
the local codes, or in the absence of local codes: The National Electrical
Code, NFPA 70 or the Canadian Electrical Code CSA C221.1.

HIGH ALTITUDE INSTALLATION

INSTALLATIONS ABO VE 7700 FT. (2,347 m) REQUIRE
REPLACEMENT OF THE BURNER ORIFICE IN ACCORDANCE
WITH NATURAL GAS AND PROPANE INSTALLATION CODE CAN/
CSA B149.1. FAILURE TO REPLACE THE ORIFICE COULD RESULT
IN IMPROPER AND INEFFICIENT OPERATION OF THE APPLIANCE,
PRODUCING CARBON MONOXIDE GAS IN EXCESS OF SAFE
LIMITS, WHICH COULD RESULT IN SERIOUS PERSONAL INJURY
OR DEATH. CONTACT YOUR GAS SUPPLIER FOR ANY SPECIFIC
CHANGES WHICH MAY BE REQUIRED IN YOUR AREA.

SOME MODEL S ARE BUILT SPECI FICALLY FOR HIGH
ALTITUDE SERVICE.

PLEASE CHECK THE RATING PLATE BEFORE MAKING CHANGES.

CAUTION

LOCATION OF HEATER

When installing the heater, consideration must be given to proper
location. Location selected should be as close to the outside wall
to be used for terminations as practicable with adequate air supply
and as centralized with the water piping system as possible.

Adequate clearance for servicing this appliance should be
considered before installation, such as changing the anodes, etc.
Minimum clearances for proper operation are given above.

In cold climates provide protection against freeze-up.

THE HEATER SHOULD BE LOCATED IN AN AREA WHERE
LEAKAGE OF THE TANK OR CONNECTIONS WILL NOT
RESULT IN DAMAGE TO THE AREA ADJACENT TO THE
HEATER OR TO LOWER FLOORS OF THE STRUCTURE.

When such locations cannot be avoided, a suitable drain pan
should be installed under the heater, see gure 1. The pan
must not restrict combustion air ow. Such pans should have a
minimum length and width of at least 2" (5.1 cm) greater than the
diameter of the heater and should be piped to an adequate drain.
Drain pans suitable for these heaters are available from the water
heater manufacturer at, 500 Tennessee Waltz Parkway, Ashland
City, TN 37015.

Installation of the water heater must be accomplished in such a
manner that if the tank or any of the connections should leak, the
ow will not cause damage to the structure. For this reason, it is
not advisable to install the water heater in an attic or upper oor.
When such locations can not be avoided, a suitable drain pan
should be installed under the water heater.

Water heater life depends upon water quality, water pressure
and the environment in which the water heater is installed. Water
heaters are sometimes installed in locations where leakage may
result in property damage, even with the use of a drain pan piped
to a drain. However, unanticipated damage can be reduced or
prevented by a leak detector or water shut-off device used in
conjunction with a piped drain pan.

These devices are available from some plumbing supply
wholesalers and retailers, and detect and react to leakage in
various ways:

• Sensors mounted in the drain pan that trigger an alarm or turn
off the incoming water to the water heater when leakage is
detected.

• Sensors mounted in the drain pan that turn off the water supply
to the entire home when water is detected in the drain pan.

• Water supply shut-off devices that activate based on the water
pressure differential between the cold water and hot water pipes
connected to the water heater.

• Devices that will turn off the gas supply to a gas water heater
while at the same time shutting off its water supply.

DO NOT INSTALL THIS WATER HEATER DIRECTLY ON A
CARPETED FLOOR. A FIRE HAZARD MAY RESULT. Instead the

water heater must be placed on a metal or wood panel extending
beyond the full width and depth by at least 3 inches (7.6 cm) in any
direction. If the heater is installed in a carpeted alcove or closet,
the entire oor shall be covered by the panel.

WARNING

WARNING

The heater is design certied by the Underwriters Laboratories Inc.
for installation on combustible ooring in a closet having minimum
clearances from combustible material of: 0" (0 cm) clearance from

AIR REQUIREMENTS

In calculating the free area of a vent opening, the blocking effect

5

of screens, louvers and grills should be considered. Screens shall
not be of a mesh smaller than 1/4" (6.3 mm) square. If the free
area is not known, the National Fuel Gas Code, ANSI Z223.1/NFPA
54 or the Natural Gas and Propane Installation Code CAN/CSA
B149.1 recommends using gures of 20-25 percent free area for
wood louvers or 60-75 percent for metal grills or louvers.

WATER CONNECTIONS

Refer to gure 1 for typical installation. A suitable pipe thread
sealant must be used to prevent leakage.\

WATER (POTABLE) HEATING AND SPACE HEATING

UNCONFINED SPACE

In buildings of conventional frame, brick or stone construction,
unconned spaces may provide adequate air for combustion,
ventilation, and dilution air for power venter.

If the unconned space is within a building of tight construction
(building using the following construction: weather stripping,
heavy insulation, caulking, vapor barrier, etc.), air for combustion,
ventilation, and venter dilution must be obtained from outdoors. The
installation instructions for conned spaces must be followed.

CONFINED SPACE

When drawing combustion and dilution air from inside a conventionally
constructed building to a conned space, such a space shall be provided
with two permanent openings. ONE WITHIN 12" (30 cm) OF THE
ENCLOSURE TOP AND ONE WITHIN 12" (30 cm) OF THE ENCLOSURE
BOTTOM. Each opening shall have a free area of one square inch (6.5 cm²)
per 1000 Btuh (292.8 W) of the total input of all appliances in the enclosure,
but not less than 100 square inches (645 cm²).

If the conned space is within a building of tight construction, air for
combustion, ventilation and power venter dilution must be obtained
from outdoors. When directly communicating with the outdoors or
communicating through vertical ducts, two permanent openings,
located in the above manner, shall be provided. Each opening shall
have a free area of not less than one square inch (6.5 cm²) per 4000
Btuh (1,171 W) of the total input of all appliances in the enclosure.
If horizontal ducts are used, each opening shall have a free area of
not less than one square inch (6.5 cm²) per 2000 Btuh (585.6 W)

of the total input of all appliances in the enclosure.

1. All piping components connected to this unit for space heating

applications shall be suitable for use with potable water.

2. Toxic chemicals, such as those used for boiler treatment, shall
NEVER be introduced into this system.

3. This unit may NEVER be connected to any existing heating
system or component(s) previously used with a non-potable

water heating appliance.

4. When the system requires water for spa ce heating at
temperatures higher than required for domestic water purposes,
a tempering valve must be installed. Please refer to Figure 2
for suggested piping arrangement.

FIGURE 2

CLOSED WATER SYSTEM

A closed system will exist if a back-ow preventer (check valve),
pressure reducing valve, or other similar device is installed in
the cold water line between the water heater and the street main
(or well). Excessive pressure may develop due to the thermal
expansion of heated water causing premature tank failure or
intermittent relief valve operation. This type of failure is not
covered by the limited warranty. An expansion tank may be
necessary in the cold water supply to alleviate this situation, see
Figure 1. Contact the local plumbing authority.

If the temperature and pressure relief valve on the appliance
discharges periodically, this may be due to thermal expansion in
a closed water supply system. Contact the water supplier or local
plumbing inspector on how to correct situation. DO NOT PLUG

THE TEMPERATURE AND PRESSURE RELIEF VALVE.

GAS CONNECTIONS

The minimum gas supply pressure for input adjustment is 5.0" (12.7
cm) W.C. for natural gas (11.0" (27.9 cm) W.C. for propane).

THE HEATER IS NOT INTENDED FOR OPERATION AT HIGHER

THAN 14" (35.6 cm) WATER COLUMN SUPPLY PRESSURE.

EXPOSURE TO HIGHER GAS SUPPLY PRESSURE MAY

CAUSE DAMAGE TO THE CONTROL WHICH COULD RESULT

IN FIRE OR EXPLOSION. If overpressure has occurred such as

through improper testing of gas lines or emergency malfunction of
the supply system, the control must be checked for safe operation.
Make sure that the outside vents on the supply regulators and
the safety vent valves are protected against blockage. These are
parts of the gas supply system not the heater. Vent blockage may
occur during ice storms.

IT IS IMPORTANT TO GUARD AGAINST CONTROL FOULING
FROM CONTAMINANTS IN THE GAS WAYS. SUCH FOULING

6

WARNING

VENT HOOD(S) MAY BE EXTREMELY HOT DURING OPERATION.

U.S. HORIZONTAL VENT CLEARANCES

CANADIAN HORIZONTAL VENT CLEARANCES

FIGURE 3

7

MAY CAUSE IMPROPER OPERATION, FIRE OR EXPLOSION.

All piping must comply with local codes and ordinances or with the
National Fuel Gas Code NFPA 70 or the Natural Gas and Propane
Installation Code CAN/CSA B149.1, whichever applies.

REFER TO FIGURE 1 FOR CONNECTION DETAILS. BEFORE
ATTACHING THE GAS LINE BE SURE THAT ALL GAS PIPE IS
CLEAN ON THE INSIDE.

TO TRAP ANY DIRT OR FOREIGN MATERIAL IN THE GAS

SUPPLY LINE, A DIRT LEG (SOMETIMES CALLED DRIP LEG)
MUST BE INCORPORATED IN THE PIPING, FIGURE. 1. The

dirt leg must be readily accessible. Install in accordance with
recommendations of serving gas supplier. Refer to the National
Fuel Gas Code, ANSI Z223.1/NFPA 54 or the Natural Gas and
Propane Installation Code CAN/CSA B149.1.

To prevent damage, care must be taken not to apply too much
torque when attaching gas supply pipe to thermostat gas inlet. The
thermostat inlet has a pad for use with a backup wrench.

Apply joint compounds (pipe dope) sparingly and only to the
male threads of pipe joints. Do not apply compound to the rst
two threads. Use compounds resistant to the action of liqueed
petroleum gases. Do not use teon tape on thermostat ttings.

CONNECTION OF GAS PIPE

1. When connecting gas pipe to unit, apply wrench to ange only.
Note: Do not use wrench on gas valve or gas valve bracket.

2. PERFORM THE GAS LEAK TEST ANY TIME WORK IS DONE

ON A GAS SYSTEM TO AVOID THE POSSIBILITY OF FIRE

OR EXPLOSION WITH PROPERTY DAMAGE, PERSONAL
INJURY, OR LOSS OF LIFE.

The Gas Leak Test is performed as follows: Paint pipe

connections upstream of gas control with a rich soap and water
solution to test for leaks before operating main burner. Bubbles
indicate gas leak. To stop leak, tighten pipe connections.
After piping connections are checked, turn on main burner.
(See Lighting and Operating Installations in this manual or on
water heater.) With main burner in operation, paint pipe joints
(including anges) and control inlet and outlet with rich soap
and water solution. Bubbles indicate gas leak. To stop leak,
tighten ange screws, joints and pipe connections. Replace
part if leak can't be stopped.

DISCONNECT THE APPLIANCE AND ITS INDIVIDUAL SHUT

OFF VALVE FROM THE GAS SUPPLY PIPING SYSTEM

DURING ANY SUPPLY PRESSURE TESTING EXCEEDING
1/2 PSI (3.5 kPa). GAS SUPPLY LINE MUST BE CAPPED
WHEN DISCONNECTED FROM THE HEATER. FOR TEST
PRESSURES AT 1/2 PSI (3.5 kPa) OR LESS, THE APPLIANCE
NEED NOT BE DISCONNECTED, BUT MUST BE ISOLATED
FROM THE SUPPLY PRESSURE TEST BY CLOSING THE MAIN

MANUAL GAS VALVE.

NOT USE MATCHES CANDLES, FLAME OR OTHER SOURCES
OF IGNITION TO LOCATE GAS LEAKS.

RELIEF VALVE

A NEW TEMPERATURE AND PRESSURE RELIEF VALVE

COMPLYING WITH THE STANDARD FOR RELIEF VALVES
AND AUTOMATIC GAS SHUT OFF DEVICES FOR HOT WATER
SUPPLY SYSTEMS, ANSI Z21.22-CSA 4.4 MUST BE INSTALLED
IN THE HEATER IN THE MARKED OPENING PROVIDED. THE
VALVE MUST BE OF A SIZE (INPUT RATING) THAT WILL BE
ADEQUATE FOR YOUR SIZE HEATER.

Check the metal tag on the relief valve and compare it to the heater’s
rating plate. The pressure rating of relief valve must not exceed the
working pressure shown on the rating plate of the heater. In addition
the hourly Btu rated temperature steam discharge capacity of the relief
valve shall not be less than the input rating of the heater. NO VALVE

IS TO BE PLACED BETWEEN THE RELIEF VALVE AND TANK. DO

NOT PLUG THE RELIEF VALVE.

The drain line connected to this valve must not contain a reducing
coupling or other restriction and must terminate near a suitable
drain to prevent water damage during valve operation. The
discharge line shall be installed in a manner to allow complete
drainage of both the valve and line. DO NOT THREAD, PLUG

OR CAP THE END OF THE DRAIN LINE.

VENTING

WARNING

NEVER OPERATE THE HEATER UNLESS IT IS VENTED TO

THE OUTDOORS AND HAS ADEQUATE AIR SUPPLY TO AVOID
RISKS OF IMPROPER OPERATION, FIRE, EXPLOSION OR

ASPHYXIATION.

VENT PIPE TERMINATION

The rst step is to determine where the vent pipe will terminate.
See Figures 3, 8 and 9. The vent may terminate through the roof as
shown in Figure 9 or through a sidewall as shown in Figure 8.

IMPORTANT

The vent system must terminate so that proper clearances are
maintained as cited in local codes or the latest edition of the
National Fuel Gas Code, ANSI Z223.1/NFPA 54 or the Natural
Gas and Propane Installation Code CAN/CSA-B149.1.

For your convenience instructions on proper installation through
a sidewall are provided in Figure 3.

The manufacturer also recommends that the vent system
termination not be installed closer than 3 feet (91 cm) from an
inside corner of an L shaped structure and not be less than 1 foot
(30 cm) above grade. The vent shall terminate a minimum of 12"
(30 cm) above expected snowfall level to prevent blockage of
vent termination.

Plan the vent system layout so that proper clearances are
maintained from plumbing and wiring.

BEFORE PLACING THE HEATER IN OPERATION, CHECK
FOR GAS LEAKAGE. USE SOAP AND WATER SOLUTION OR
OTHER MATERIAL ACCEPTABLE FOR THIS PURPOSE. DO

Vent pipes serving power vented appliances are classied by
building codes as "vent connectors". Required clearances from
combustible materials must be provided in accordance with
information in this manual under LOCATION OF HEATER and
INSTALLATION OF VENT SYSTEM, and with the National Fuel

8

Gas Code, ANSI Z223.1/NFPA 54 or the Natural Gas and
Propane Installation Code CAN/CSA B149.1.

PLANNING THE VENT SYSTEM

Plan the route of the vent system from the discharge of the blower
to the planned location of the vent terminal.

1. Layout the total vent system to use a minimum of vent pipe
and elbows. Take into consideration that an elbow will be
necessary to make the rst vent pipe connection to the power
venter outlet (see Figure 6).

2. This water heater is capable of venting the ue gases
the equivalent of thirty (30) feet (9.1 m) of 3 inch pipe or
one-hundred (100) feet (30.5 m) of 4 inch pipe as listed

in Table 1.

TABLE 1

Number of 3" Maximum 4" Maximum

90° Elbows Pipe Pipe

ONE (1) 25 ft (7.6 m) 92 ft (28.0 m)

TWO (2) 20 ft (6.1 m) 84 ft (25.6 m)

THREE(3) 15 ft (4.6 m) 76 ft (23.2 m)

FOUR (4) 10 ft (3.0 m) 68 ft (20.7 m)

FIVE (5) - - - 60 ft (18.3 m)

Minimum of one (1) elbow and 2 feet (61 cm) of straight pipe

must be installed for 3" and 4" pipe.

NOTE: The equivalent length of pipe listed above are exclusive

of the "45° Elbow" termination. That is, the termination "45°
Elbow", with installed screen, is assumed to be in the system
and the remainder of the system must not exceed the thirty
(30) equivalent feet (9.1 equivalent meters) of 3 inch pipe or
one-hundred (100) equivalent feet (30.5 equivalent meters) of

4 inch pipe.

3. The blower discharge adapter is made to accept only straight
sections of 3" pipe. To start a minimum of 2 inches (5.1 cm)
of 3" pipe must be attached to the blower discharge (See

Figure 6).

FIGURE 4

NOTE: This unit can be vented using only PVC (Class 160,

ASTM D-2241; Schedule 40, ASTM D-1785; or Cellular Core
Schedule 40 DWV, ASTM F-891), Schedule 40 CPVC/ASTM
F-441), or ABS/ASTM D-2661) pipe. The ttings, other than the
TERMINATION 45° ELBOW should be equivalent to PVC-DWV
ttings meeting ASTM D-2665 (Use CPVC ttings, ASTM F-438
for CPVC pipe and ABS ttings, ASTM D-2661/3311 for ABS
pipe. If CPVC or ABS pipe and ttings are used, then the proper
cement must be used for all joints, including joining the pipe
to the Termination 45° Elbow (PVC Material). If local codes do
not allow the use of the PVC termination when a material other
than PVC is used for venting, than an equivalent tting of that
material may be substituted if the screen in the PVC terminal
is removed and inserted into the new tting.

PVC Materials should use ASTM D-2564 Grade Cement; CPVC

Materials should use ASTM F-493 Grade Cement and ABS
Materials should use ASTM D-2235 Grade Cement.

NOTE: A. For water heaters in locations with high ambient

temperatures above 100°F (38°C) and/or insufcient dilution
air, it is recommended that CPVC or ABS pipe and ttings
be used. B. The SUPPLIED VENT TERMINAL or a precisely
identical vent terminal of CPVC or ABS material must be used
in all cases. If a new terminal is used, the screen inside the
supplied terminal must be installed into the new terminal.

4. The temperature of the ue gases leaving the blower is about
160°F (71°C) after mixing the dilution air in the inlet adapter of
the blower. Even with high concentrate of room air taken into
the vent system for dilution air, there will be some installations
where condensate will be formed in the horizontal runs of the
vent system.

If using 3 inch vent pipe:

A minimum of 2 inches (5.1 cm), maximum of 4 feet (1.2 m)

of 3" pipe must be attached to the blower before the rst 3
inch elbow. After the rst elbow add the additional venting
required for the installation. The total system cannot exceed
30 equivalent feet (9.1 equivalent meters) of venting, where
each elbow is equal to 5 feet (1.5 m) of straight pipe.

If using 4 inch vent pipe:

Two inches (5.1 cm) of 3" pipe must be attached to the

blower discharge. A 4" x 3" reducer is added and then up
to maximum 4 feet (1.2 m) of 4 inch pipe added before the
rst elbow. An additional 4" x 3" reducer and (1) foot (30
cm) of 3" pipe must be added to the end of the vent system
before terminating into the 3" 45° elbow. The total system
cannot exceed 100 equivalent feet (30.5 equivalent meters)
of 4" venting, where each elbow is equal to 8 feet (2.4 m) of

straight pipe.

CONDENSATE

Condensate formation does not occur in all installations of
power vented water heaters, but should be protected against
on installations where it can form in the venting system.
Condensation in the venting system of power vented water
heaters is dependent upon installation conditions including, but
not limited to ambient temperature and humidity of installation
location, ambient temperature and humidity of venting space,
vent discharge and slope, and product usage. In certain
conditions, installations in unconditioned space or having long
horizontal or vertical vent runs may accumulate condensate.
In these conditions, the vent pipe should be sloped downward
away from the blower assembly (not less than 1/8" (3.2 mm)
nor greater than 1/2" (12.7 mm) per foot (30 cm) maximum).
If the vent piping is vented level or 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 condensate is detected). If you have condensate, then a

9

3/8" drain hose can be connected to the built-in drain port of
the rubber boot on the blower assembly. For your convenience,
the rubber boot is supplied with a removable cap on the built-in
drain port. Prior to operating the water heater, make sure the
removable cap is installed on the drain port (if a drain hose is
not needed).

INSTALLATION OF VENT SYSTEM

PREPARATION OF BLOWER ASSEMBLY

1. Check to make sure that the wire harness is attached to the
gas valve and blower control box.

2. Make sure no material is still attached to the outside or inside
of blower assembly.

Before beginning installation of piping system thoroughly read the
section of this manual VENT PIPE PREPARATION.

If you are installing your system so that it vents through roof, please
refer to following section titled INSTALLATION OF VERTICAL

VENT SYSTEM.

VENT TERMINAL INSTALLATION, SIDEWALL

1. Install the vent terminal by using the cover plate as a template
to mark the hole for the vent pipe to pass through the wall.
BEWARE OF CONCEALED WIRING AND PIPING INSIDE

THE WALL.

2. If the Vent Terminal is being installed on the outside of a nished
wall, it may be easier to mark both the inside and outside wall.
Align the holes by drilling a hole through the center of the
template from the inside through to the outside. The template
can now be positioned on the outside wall using the drilled hole
as a centering point for the template.

3. A) MASONRY SIDE WALLS

Chisel an opening approximately one half inch (13 mm) larger

than the marked circle.

B) WOODEN SIDE WALLS

Drill a pilot hole approximately one quarter inch (6.4 mm) outside

of the marked circle. This pilot hole is used as a starting point
for a saws-all or sabre saw blade. Cut around the marked circle
staying approximately one quarter inch (6.4 mm) outside of the
line. (This will allow the vent to easily slide through the opening.
The resulting gap will be covered up by the Vent Terminal cover
plate.) Repeat this step on inside wall if necessary.

SEQUENCE OF INSTALLATIONS, FIGURE 5

Cut a length of 3" PVC pipe about 3.5 inches (8.9 cm) longer
than the wall thickness at the opening. Glue the vent terminal
"45° Elbow" with screen to this section of pipe. Slide the wall
plate over the pipe to stop against "45° Elbow". Place a bead
of caulking (not supplied) around the gap between the pipe and
cover plate. Apply enough to ll some of the gap between the
pipe and wall. Place some of the caulking on the back of the
plate to hold it against the wall after installation. If the vent pipe
is installed up to the wall, with a coupling on the end against the
wall opening, the pipe with the vent terminal can be prepared for
gluing before inserting through the wall. Slide the pipe through
the wall and insert into the coupling on the other side of the wall,
making sure that the vent terminal ends up pointed in the correct
position. (See gure 5).

MU ST INS TAL L MI NI MU M O F 2"
(5.1 cm) LONG PIECE OF 3" PIPE INTO
ELBOW TO MOUNT ON BLOWER
DISCHARGE ADAPTER. MAXIMUM
LENGTH FOUR (4) FEET (1.2 m).

FIGURE 6

3. Make sure that plastic tubing is still attached to the pressure
switch and fan housing. Also make sure that wiring connector
from motor to control box is securely attached.

4. Do not plug in power cord until vent system is completely
installed. The Power Vent operates on 120 Vac, therefore
a grounded outlet must be within reach of the 6 foot
(1.8 m) exible power cord supplied with the vent (see gure

1). The power cord supplied may be used on unit only where
local codes permit. If local codes do not permit use of exible
power supply cord:

A. Remove screws that hold cover plate on control box and

remove plate.

B. Cut exible power cord on inside of control box, as close

to inside wall as possible.

C. If exible cord and strain relief are removed, then opening

in box must be covered by a plastic cap on the front side
of the control box.

D. Remove plastic cap on the right side of control box and

install suitable conduit tting in enclosure.

E. Splice eld wiring into existing wiring using code authorized

method (wire nuts, etc.).

F. Be certain that neutral and line connections are not reversed

when making these connections.

G. Ground heater properly. This water heater must be

grounded in accordance with the National Electrical Code
NFPA 70 or the Canadian Electrical Code CSA C22.1 and/
or local codes. These must be followed in all cases.

VENT TERMINATION - FIGURE 5

The water heater must be connected to a grounded metal,

permanent wiring system; or an equipment grounding
conductor must be run with the circuit conductors and
connected to the equipment grounding terminal or lead on
the water heater, see Figure 7.

H. Replace cover plate and secure with two screws.

10

CAUTION

LABEL ALL WIRES PRIOR TO DISCONNECTION WHEN SERVICING CONTROLS. WIRING ERRORS CAN
CAUSE IMPROPER AND DANGEROUS OPERATION. VERIFY PROPER OPERATION AFTER SERVICING.

POWER VENT WIRING SCHEMATIC - FIGURE 7

11

5. The blower discharge boot is made to accept only straight
sections of 3" pipe. To start off with an elbow, a short section
of the furnished pipe, a minimum of 2 inches (5.1 cm), must
be cut and glued into the end of the elbow that will mount on
the discharge boot (see gure 6).

INSTALLATION OF VENT SYSTEM, SIDEWALL

With the route of the venting system and selection of materials
completed, as discussed in section of this manual titled PLANNING
THE VENT SYSTEM, the through the wall vent terminal in place
and the rst section of piping, up to rst elbow, installed at the
blower it is time to complete the installation of the venting system
for the sidewall installation.

NOTE: The equivalent length of pipe listed above are exclusive
of the "45° Elbow" termination with installed screen.

Provide support for all pipe protruding through the roof. All piping
should be properly secured. The vent system piping should be
supported every 5 feet (1.5 m) of vertical run and every 3 feet
(91 cm) of horizontal run. All piping and ttings must be joined
by the proper procedures as described under: VENT PIPE

PREPARATION.

FIGURE 8

Before completing the installation of the venting system be sure
to read the sections of this manual discussing the proper method
of cutting and cementing PVC pipe and ttings: VENT PIPE

PREPARATION.

It is recommended that the completion of the venting system start
at the blower assembly and run to the coupling on the inside wall
of the vent terminal, Figure 5.

The vent system piping should be supported every 5 feet (1.5 m)
of vertical run and every 3 feet (91 cm) of horizontal run. All piping
and ttings must be joined by the proper procedures as described
under: VENT PIPE PREPARATION.

INSTALLATION OF VERTICAL VENT SYSTEM

This unit is approved for venting through the roof with only the
vent terminal that is included with the unit, see Figure 9. A proper
ashing or "BOOT" should be used to seal the pipe where it exits
the roof. The total vent system should not exceed the thirty (30)
equivalent feet (9.1 equivalent meters) of 3 inch pipe or one­hundred (100) equivalent feet (30.5 equivalent meters) of 4 inch
pipe as listed in Table 1.

FIGURE 9

IMPORTANT

The vent system must terminate so that proper clearances are
maintained as cited in local codes or the current edition of the
Natural Gas and Propane Installation Code CAN/CSA B149.1
and as listed below:

1. Vent Termination must extend a minimum of 12 inches
(30 cm) above roof or 12 inches (30 cm) above the anticipated
snow level to prevent blockage of the vent termination. Also

see Figure 3.

VENT PIPE PREPARATION

1. INITIAL PREPARATION

A. Make sure the solvent cement you are planning to use is

designed for the specic application you are attempting.

B. Know the physical and chemical characteristics and limitations

of the PVC and CPVC piping materials that you are about to

use.

C. Know the reputation of your manufacturer and their products.

D. Know your own qualications or those of your contractor. The

solvent welding technique of joining PVC and CPVC pipe is a
specialized skill just as any other pipe tting technique.

E. Closely supervise the installation and inspect the nished job

before start-up.

12

F. Contact the manufacturer, supplier, or competent consulting

agency if you have any questions about the application or
installation of PVC and CPVC pipe.

G. Take the time and effort to do a professional job. Shortcuts will

only cause you problems and delays in start-up. By far, the
majority of failures in PVC and CPVC systems are the result
of shortcuts and/or improper joining techniques.

2. SELECTION OF MATERIALS

• Cutting Device - Saw or Pipe Cutter

• Deburring Tool, Knife, File, or Beveling Machine (2" (5.1 cm)
and above)

• Brush - Pure Bristle

• Rag - Cotton (Not Synthetic)

• Primer and Cleaner

• Solvent Cement - PVC for PVC Components and CPVC for
CPVC Components

• Containers - Metal or Glass to hold Primer and Cement. Select
the type of PVC or CPVC materials to be used on the basis of
their application with respect to chemical resistance, pressure
rating, temperature characteristics, etc.

• Insertion Tool - Helpful for larger diameter pipe and ttings

(6" (15.2 cm) and above).

PRIMER

It is recommended that Tetrahydrofuran (THF) be used to prepare
the surfaces of pipe and ttings for solvent welding. Do not use
water, rags, gasoline or any other substitutes for cleaning PVC or
CPVC Surfaces. A chemical cleaner such as MEK may be used.

CEMENT

The cement should be a bodied cement of approximately 500 to
1600 centipoise viscosity containing 10-20% (by weight) virgin PVC
material solvated with tetrahydrofuran (THF). Small quantities of
dimethyl formamide (DMF) may be included to act as a retarding
agent to extend curing time. Select the proper cement; Schedule
40 cement should be used for Schedule 40 pipe. Never use all­purpose cements, commercial glues and adhesives or ABS cement
to join PVC or CPVC pipe and ttings.

SAFETY PRECAUTION: PRIMERS A ND CEMENTS A RE
EXTREMELY FLAMMABLE, AND MUST NOT BE STORED OR
USED NEAR HEAT OR OPEN FLAME. ALSO, USE ONLY IN A

WELL-VENTILATED AREA.

APPLICATORS

Select a suitable pure bristle type paint brush. Use a proper width
brush or roller to apply the primer and cement (see chart below).
Speedy application of cement is important due to its fast drying
characteristics. IMPORTANT NOTE: A dauber type applicator
should only be used on pipe sizes 2" (5.1 cm) and below. For
larger diameter pipe, a brush or roller must be used.

3. MAKING THE JOINT

STEP A

NOTE: Power saws should be specically designed to cut

plastic pipe.

B. Deburring

Use a knife, plastic pipe deburring tool, or file to remove

burrs from the end of small diameter pipe. Be sure to
remove all burrs from around the inside as well as the
outside of the pipe. A slight chamfer (bevel) of about
10°- 15° sh ould be adde d to the en d to pe rmit easier
insertion of the pipe into the end of the fitting. Failure to
chamfer the edge of the pipe may remove cement from
the fitting socket, causing the joint to leak.

STEP B

C. Test dry t of the joint

Tapered fitting sockets are designed so that an interference

fit should occur when the pipe is inserted about 1/3 to
2/3 of the way into the socket. Occasionally, when pipe
fitting dimensions are at the tolerance extremes, it will be
possible to fully inser t dry pipe to the bot tom of the fitting
socket. When this happens, a suf ficient quantity of cement
must be applied to the joint to fill the gap between the
pipe and f it ting. The gap must be f illed to obtain a strong,
leak-free joint.

D. Inspection, cleaning, priming

Visually inspect the inside of the pipe and tting sockets and

remove all dirt, grease or moisture with a clean dry rag. If
wiping fails to clean the surfaces, a chemical cleaner must be
used. Check for possible damage such as splits or cracks and

replace if necessary.

A. Cutting

Pipe must be squarely cut to allow for the proper interfacing of the

pipe end and the tting socket bottom. This can be accomplished
with a miter box saw or wheel type cutter. Wheel type cutters are
not generally recommended for larger diameters since they tend
to are the corner of the pipe end. If this type of cutter is used,
the are on the end must be completely removed.

Depth-of-entry mark

Marking the depth of entry is a way to check if the pipe has

reached the bottom of the fitting socket in step F. Measure
the fitting depth and mark this distance on the pipe O.D.
You may want to add several inches to the distance and
make a second mark as the primer and cement will most
likely destroy your first one.

13

Apply primer to the surface of the pipe and tting socket with

a natural bristle brush (see chart). This process softens and
prepares the PVC or CPVC for the solvent cementing step.
Move quickly and without hesitation to the cementing procedure
while the surfaces are still wet with primer.

E. Application of solvent cement

• Apply the solvent cement evenly and quickly around the
outside of the pipe at a width a little greater than the depth
of the tting socket.

• Apply a light coat of cement evenly around the inside of the
tting socket. Avoid puddling.

• Apply a second coat of cement to the pipe end.

The joint should not be disturbed immediately after the

ce m enti ng pro cedu re, an d suff icie nt tim e shou ld be
allowed for proper curing of the joint. Exact drying time is
difficult to predict because it depends on variables such
as temperature, humidity and cement integrity. For more
specific information, you should contact your solvent cement
manufacturer.

STEP G

STEP E

NOTE: Cans of cement and primer should be closed at all times

when not in use to prevent evaporation of chemicals and hardening
of cement. They are also very ammable and should be kept away
from heat or ame.

F. Joint assembly

Working quickly, insert the pipe into the tting socket bottom

and give the pipe or tting a 1/4 turn to evenly distribute the
cement. Do not continue to rotate the pipe after it has hit the
bottom of the tting socket. A good joint will have sufcient
cement to make a bead all the way around the outside of the
tting hub. The tting will have a tendency to slide back while
the cement is still wet so hold the joint together for about 15
seconds.

STEP F

G. Cleanup and joint movement

Remove all excess cement from around the pipe and tting

with a dry cotton rag. This must be done while the cement

is still soft.

OPERATION

WARNING

DO NOT ATTEMPT TO OPERATE WATER HEATER WITH COLD
WATER INLET VALVE CLOSED.

NEVER OPERATE THE HEATER WITHOUT FIRST BEING

CERTAIN IT IS FILLED WITH WATER AND A TEMPERATURE

AND PRESSURE RELIEF VALVE IS INSTALLED IN THE RELIEF
VALVE OPENING OF THE HEATER.

TO OPERATE THE HEATER

1. Close the heater drain valve by turning handle clockwise .

2. Open a nearby hot water faucet to permit the air in the system

to escape.

3. Fully open the cold water inlet pipe valve allowing the heater
and piping to be lled.

4. Close the hot water faucet as water starts to ow.

5. The heater is ready to be operated.

CAUTION

THE "ON/OFF" SWITCH ON THE CONTROL BOX SHOULD
NOT BE TURNED TO THE "OFF" POSITION UNLESS THE
UNIT IS BEING SERVICED.

14

FOR YOUR SAFETY READ BEFORE LIGHTING

WARNING: If you do not follow these instructions exactly, a re or

explosion may result causing property damage, personal injury or loss
of life.

BEFORE OPERATING: ENTIRE SYSTEM MUST BE FILLED WITH WATER AND AIR PURGED FROM ALL LINES.

A. This appliance does not have a pilot. It is equipped

with an ignition device which automatically lights the
burner. Do NOT try to light the burner by hand.

B. BEFORE OPERATING smell all around the appliance

area for gas. Be sure to smell next to the oor because
some gas is heavier than air and will settle on the
oor.

WHAT TO DO IF YOU SMELL GAS:

• Do not try to light any appliance.

• Do not touch any electric switch;
do not use any phone in your building.

• Immediately call your gas supplier from a neighbor’s
phone. Follow the gas supplier’s instructions.

• If you cannot reach your gas supplier, call the re
department.

C. Use only your hand to push in the gas control

buttons. Never use tools. If the control buttons will
not push in, don’t try to repair them, call a qualied
service technician. Force or attempted repair may
result in a re or explosion.

D. Do not use this appliance if any part has been

under water. Immediately contact a qualified
installer or service agency to replace a ooded
water heater. Do not attempt to repair the unit. It
must be replaced!

OPERATING INSTRUCTIONS

5. This appliance is equipped with a device which
automatically lights the burner.

DO NOT TRY TO LIGHT THE BURNER BY HAND.

1. STOP! Read the safety information above

2. Set the ON/OFF switch on the control box to the
"ON" position.

3. Set the thermostat to the lowest setting by rst
pressing the COOLER
together and holding for 1 second. Then press the
COOLER

appears.

4. Set the ON/OFF switch on the control box to the
"OFF" position.

on this label.

and HOTTER buttons

button until the warm indicator light

TO TURN OFF GAS TO APPLIANCE

6. Wait ve (5) minutes to clear out any gas.
If you then smell gas, STOP! Follow "B"
in the safety information above on this label. If you
don't smell gas, go to the next step.

7. Turn on all electrical power to the appliance.

8. Set the ON/OFF switch on the control box to the
"ON" position.

9. Set the thermostat to the desired setting by rst
pressing the COOLER
together and holding for 1 second. Then press the

HOTTER

10. WATER TEMPERATURE ADJUSTMENT
approximately 120°F.

CAUTION: Hotter water increases the risk

11. If the appliance will not operate, follow the instructions
"TO TURN OFF GAS TO THE APPLIANCE" and call

your technician or gas supplier.

WARNING: TURN OFF ALL ELECTRIC

button.

of scald injury. Consult the instruction

manual before changing temperature.

POWER BEFORE SERVICING.

and HOTTER buttons

is

1. Set the thermostat to the lowest setting by rst
pressing the COOLER
buttons together and holding for 1 second. Then
press the COOLER
indicator light appears.

and HOTTER

button until the warm

2. Set the ON/OFF switch on the control box to the
"OFF" position.

3. Turn off all electrical power to the appliance if service
is to be performed.

15

TEMPERATURE REGULATION

DANGER

THIS WATER HEATER IS EQUIPPED WITH AN ADJUSTABLE
THERMOSTAT TO CONTROL WATER TEMPERATURE. HOT
WATER TEMPERATUR ES REQU IRED FOR AUTOMATIC
DISHWASHING AND LAUNDRY USE CAN CAUSE PAINFUL
SCALDING WITH POSSIBLE SERIOUS AND PERMANENT
INJURY. THE TEMPERATURE AT WHICH INJURY OCCURS

VARIES WITH THE PERSON'S AGE AND THE TIME OF THE

EXPOSURE. THE SLOWER RESPONSE TIME OF CHILDREN,
AGED OR DISABLED PERSONS INCREASES THE HAZARDS
TO THEM. NEVER ALLOW SMALL CHILDREN TO USE A HOT
WATER TAP, OR TO DRAW THEIR OWN BATH WATER. NEVER
LEAVE A CHILD OR DISABLED PERSON UNATTENDED IN A

BATHTUB OR SHOWER.

THE WATER HEATER SHOULD BE LOCATED IN AN AREA
WHERE THE GENERAL PUBLIC DOES NOT HAVE ACCESS.
IF A SUITABLE AREA IS NOT AVAILABLE, A COVER SHOULD

BE INSTALLED OVER THE THERMOSTAT TO PREVENT

TAMPERING. Suitable covers are available through A.O. Smith
Water Products Company, 500 Tennessee Waltz Parkway, Ashland
City, TN 37015. In Canada, A.O. Smith Enterprises, LTD., P.O. Box
310-768 Erie Street, Stratford, Ontario N5A 6T3.

1. "Wake Up" the temperature indicators by holding down both the
"COOLER" and "HOTTER" temperature adjustment buttons at
the same time for one second (see Figure 10). One or two of
the temperature indicators will light up. These indicators will
only remain on for 30 seconds if no further buttons are pressed.
After 30 seconds the control will go back to "Sleep" mode.

2. Release both of the temperature adjustment buttons.

A. To decrease the temperature press and release the

"COOLER" button until desired setting is reached.

B. To increase the tempera ture press and release the

"HOTTER" button until the desired setting is reached.

NOTE: Holding down the button will not continue to lower or raise
the temperature setting. The button must be pressed and released
for each temperature change desired.

SHOULD OVERHEATING OCCUR OR THE GAS SUPPLY FAIL
TO SHUT OFF, TURN OFF THE MAIN MANUAL GAS SHUT OFF
VALVE TO THE APPLIANCE, SEE FIGURE 1 (G).

TEMPERATURE INDICATORS

It is recommended that lower water temperatures be used to avoid
the risk of scalding. It is further recommended, in all cases, that
the water temperature setting be set for the lowest temperature
that satises your hot water needs. This will also provide the
most energy efcient operation of the water heater. The water
temperature adjustment was factory set at the lowest temperature.
Pressing the "COOLER"
pressing the "HOTTER"

button decreases temperature and

button increases the temperature.

SETTING THE WATER HEATER TEMPERATURE AT 120°F
(49°C) (APPROX. " " MARK ON FACE OF THE TEMPERATURE
ADJUSTING DIAL) WILL REDUCE THE RISK OF SCALDS. Some

states require settings at specic lower temperatures.

Figure 10 shows the approximate water temperatures produced
at various thermostat settings. Short repeated heating cycles
caused by small hot water uses can cause temperatures at the
point of use to exceed the thermostat setting by up to 20°F (11°C).
If you experience this type of use you should consider using lower
temperature settings to reduce scald hazards.

Valves for reducing point of use temperature by mixing cold and
hot water are available. Also available are inexpensive devices
that attach to faucets to limit hot water temperatures. Contact a
licensed plumber or the local plumbing authority.

To avoid any unintentional changes in water temperature settings,
the control has a tamper resistant feature for changing the
temperature setting. To change the temperature setting follow
these instructions:

THERMOSTAT ADJUSTMENT BUTTONS

Time to Produce

Temperature Setting Display 2nd & 3rd Degree

B C D E F Burns on Adult Skin

F = approx. 180°F (82°C) Nearly Instantaneous

E = approx. 170°F (77°C) Nearly Instantaneous

D = approx. 160°F (71°C) About 1/2 Second

C = approx. 150°F (65°C) About 1 1/2 Seconds

B = approx. 140°F (60°C) Less than 5 Seconds

B = approx. 130°F (54°C) More than 30 Seconds

= approx. 120°F (49°C) More than 5 Minutes

FIGURE 10

MAINTENANCE

CAUTION

DIS C ONNE C T FROM EL E CTRI C AL SU P PLY BEF O RE
SERVICING UNIT. FOR YOUR SAFETY, WATER HEATER
SERVICE SHOULD BE PERFORMED ONLY BY A QUALIFIED
SERVICE TECHNICIAN. READ THE GENERAL SAFETY
INFORMATION SECTION FIRST.

16

USERS OF THIS APPLIANCE SHOULD BE AWARE THAT GAS
COMPONENTS WEAR OUT OVER A PERIOD OF TIME. THE
GAS CARRYING COMPONENTS OF THIS APPLIANCE SHOULD
BE INSPECTED FOR PROPER OPERATION PERIODICALLY
BY A QUALIFIED SERVICE TECHNICIAN.

MAIN BURNER

POWER VENTER MAINTENANCE

The water heater must be inspected quarterly. Points of
inspection are:

1. MOTOR - Motor must rotate freely. This is a sealed motor
and no oiling is required.

Check main burner every 12 months for proper ame characteristics.
This is done by removing door(s) on heater, g. 1. The main burner
should provide complete combustion of gas; ignite rapidly; give
reasonably quiet operation; cause no excessive ame lifting from
burner ports. Make sure that the ow of combustion and ventilation
air is not blocked.

WARNING

Use appropriate caution when performing this inspection and
do not put any part of your body immediately in front of the
combustion chamber.

If proper flame characteristics are not evident, c heck for
accumulation of lint or other foreign material that restricts or

blocks the air openings in the heater or burner. Also check AIR

REQUIREMENTS.

WARNING

SOOT BUILD-UP INDICATES A PROBLEM THAT REQUIRES
CORRECTION BEFORE FURTHER USE. Consult with a qualied
service technician.

Should the main burner or burner air openings require cleaning,
turn the control switch to “OFF” position and allow the burner to
cool. Remove the burner and clean with a soft brush. Clean main
burner orice with a suitable soft material.

HIGH TEMPERATURE LIMIT SWITCH

2. WHEEL - Wheel must be clean of soot, ash or any other
coating which inhibits either rotation or air ow. Remove all
foreign material from vent system before operating.

3. AIR SUPPLY BOX - Every month check operation and make
sure nothing is blocking dilution air entrance.

4. The pressure switch part inside the power venter must be
open and free from deposits of soot, carbon, etc.

For safety and satisfactory operation it is recommended that the
heater be checked once a year by a competent service person.

The thermostat has a single use built-in limit switch which will shut
off gas to burner in case of excessive water temperatures. The
thermostat must be replaced if the limit switch opens.

VENTING SYSTEM

HAVE VENTING SYSTEM CHECKED EVERY SIX MONTHS FOR
OBSTRUCTIONS AND/OR DETERIORATION IN VENT PIPING.

A. Insofar as is practical, close all doors, windows and air inlets to

the building. Turn on all exhaust fans (range hood, bathroom
exhaust, etc.) so they will operate at their maximum speed.
Close replace dampers.

B. Turn water temperature adjusting knob to full, counterclockwise

and open water faucet if necessary to keep burner in

operation.

C. “CHECKING THE DRAFT.” Operate the water heater for

several minutes and check to see if it is venting properly by
passing a lit match or paper near the opening of the Air Mixing
Box (See gure 11). If the draft is proper, the match ame
will be drawn into the Air Mixing Box. If not, the combustion
products will tend to extinguish the ame. If an improper draft
exists, do not operate the water heater until proper adjustments
or repairs are made to provide adequate draft through the gas
vent.

D. Next, turn on all other fuel burning appliances within the same

room so they will operate at their full input.

Repeat step C above.

FIGURE 11

T & P VALVE

At least once a year, the temperature and pressure relief valve
must be checked to ensure that it is in operating condition. Lift
the lever at the top of the valve several times until the valve seats
properly and operates freely.

WARNING

THE WATER PASSING OUT OF THE VALVE DURING THIS

CHECKING OPERATION MAY BE EXTREMELY HOT. AVOID
CONTACT AND DISCHARGE SAFELY TO PREVENT WATER

DAMAGE.

DRAINING

Periodically open the drain valve and allow the water to run until
it ows clean. This will help prevent sediment build-up in the

tank.

It is normal for lime and scale deposits to form within the tank
and on the heat exchanger surfaces. Such deposits will not
be removed by periodic draining. It is necessary to chemically
delime the affected parts in water areas where such deposits
are encountered. Deliming information can be obtained from the
water heater manufacturer at, 500 Tennessee Waltz Parkway,
Ashland City, TN 37015.

17

If the heater is to be shut off and exposed to freezing temperatures,
it must be drained. Water, if left in the tank and allowed to freeze,
will damage the heater.

• Turn off the gas and cold water inlet valve to the heater.

• Open a nearby hot water faucet and the heater drain valve.

• BE CAREFUL TO GRASP THE DRAIN VALVE HANDLE SO

THAT THE HAND IS NOT EXPOSED TO HOT WATER. IF

DESIRED, A HOSE MAY BE CONNECTED TO THE DRAIN
VALVE TO CARRY THE WATER AWAY.

WARNING: The water CAN BE HOT.

The drain valve must be left open during the shutdown period.

• To restart heater, refer to the instructions under OPERATION.

CONDENSATION

Water vapor can condense on the cooler surfaces of the tank
forming droplets, these drip into the re or run out on the oor.
This is common at the time of startup after installation, during
periods of time when incoming water is very cold, or if the water
heater is undersized for the application.

Droplets from the bottom of the ue may be due to corrosive
combustion products or improper vent. Check with your dealer
for more information.

If you are having a problem with your water heater and are not
pleased with the service you received:

• First, please contact your dealer or the authorized service agent
in your area and explain to them why you are not satised. This
will usually correct the problem.

• If after working with your dealer or service agent the problem
has not been resolved to your satisfaction, please let us
know by either going to our website and e-mailing us or by
addressing an envelope to the manufacturer listed on the
rating plate at:

Service Department
500 Tennessee Waltz Parkway
Ashland City, TN 37015

Please be sure to provide the following information when writing
or e-mailing:

• Model Number

• Serial Number

• Date of Original Purchase

• Date Problem Originated

• Explanation of Problem

Also, please be sure to include a daytime telephone number.

TROUBLE SHOOTING

CATHODIC PROTECTION-ANODE

The anode rod is used to protect the tank from corrosion. Most
hot water tanks are equipped with an anode rod. The submerged
rod sacrices itself to protect the tank. Instead of corroding the
tank, water ions attack and eat away the anode rod. This does
not affect the water’s taste or color. The rod must be maintained
to keep the tank in operating condition.

Anode deterioration depends on water conductivity, not
necessarily water condition. A corroded or pitted anode rod
indicates high water conductivity and should be checked and/
or replaced more often than an anode rod that appears to be
intact. Replacement of a depleted anode rod can extend the
life of your water heater. Inspection should be conducted by
a qualied technician, and at a minimum should be checked
annually after the warranty period.

A hydrogen sulde (rotten egg) odor may result if water contains
high sulfate and/or minerals. Chlorinating the water supply
should minimize the problem. (See EXTENDED NON-USE

PERIODS).

NOTE: Anode must remain installed (except for inspection) to
avoid shortening tank life. See LIMITED WARRANTY. Replace

as necessary.

SERVICE AND REPAIR

Water heater may exhibit problems that are unrelated to a
malfunction of the water heater itself. The following information
and tables may serve to answer your question about a problem
that you are having without having to call a service agent.

For your safety, water heater service should be performed only
by a qualied service technician. Read the GENERAL SAFETY
INFORMATION section rst.

WATER HEATING IGNITION SEQUENCE

(Make sure gas and electric power are connected properly)

1) The ignition control module is powered and monitors the
system, waiting for a call for heat from the thermostat.

2) The thermostat calls for heat by reading a resistance value within
a given range directly proportional to water temperature.

3) The Control Module:

a) Check the pressure switches for an open circuit.

b) Energizes the blower.

c) Checks the pressure switches for a closed circuit to prove draft.
d) Sends line voltage to the hot surface igniter with a

20-second warm up period.

e) Opens the gas valve and check the sensing rod for

ame.

The water heater requires no special care other than the normal
maintenance as noted above. If you are having a problem with
your water heater, before calling for service please refer to the
following TROUBLE SHOOTING sections. If service becomes
necessary, contact your dealer, installer or an authorized
service agent. Do not attempt to repair the water heater
yourself. Any work performed by unauthorized personnel may
void the warranty.

4) The burner heats the water to the desired thermostat setting.

a) The resistance in the thermostat rises to the value selected

by the temperature control knob.

b) The control module closes the gas valve and 5 seconds

later, removes power from the blower.

5) Cycle is completed.

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WARNING: DO NOT BY-PASS ANY CONTROLS TO MAKE HEATER OPERATE. OPERATE ONLY AS WIRED FROM FACTORY.

TROUBLE SHOOTING

For your safety, water heater service should be performed only by a qualied service technician.

Read the GENERAL SAFETY INFORMATION section rst.

PROBLEM POSSIBLE MALFUNCTION SERVICE TO BE PERFORMED

1) Blower will not run

NOT ENOUGH OR

NO HOT WATER

VENT PIPE TOO HOT

(ABOVE 170° F)

YELLOW FLAME

CONDENSATION

WATER LEAKS

LEAKING T&P VALVE

HOT WATER ODORS OR COLOR

(Refer to CATHODIC PROTECTION)

HEATER LIGHT GOES OUT

IN 4-5 SECONDS

A) “ON/OFF” control switch turned off
B) Blower unplugged
C) No power at outlet
D) “ON/OFF” switch defective
E) Control harness defective
F) Blower motor defective

2) Blower running, burner not on

A) Fan not running fast enough to close
air switch contacts

B) Air pressure switch defective
C) Gas valve defective
D) Control harness defective
E) Igniter defective
F) Unit has completed three trials to light
and failed

G) Discharge air limit tripped

3) Thermostat problems
A) Thermostat set too low
B) Thermostat or ECO defective
C) High limit control circuit open

4) Others

A) Heater undersized

B) Low gas pressure

C) Incoming water is unusually cold
D) Leaking hot water pipes or xtures
E) Polarity reversed
F) Heater not grounded
A) Blower does not run when heater red

B) Not enough dilution air to mix with ue

gases

C) Air in room too hot for mixing with ue gases

D) Wrong burner orice

A) Dirt in burner ports

B) Combustion air path restricted

C) Not enough room air for proper combustion

A) Water on the oor under heater

Improperly sealed, hot or cold supply connections,
relief valve, drain valve or thermostat threads
Leakage from other appliances or water lines
Condensation of ue products
Thermal expansion in closed water system
Improperly seated valve
High sulfate or mineral content in water supply or
iron or sulfate reducing bacteria in water supply
Outlet polarity is reversed

19

Turn switch to the “ON” position.

Plug blower back into 115 vac. outlet.
Repair service to outlet.

Replace switch.
Replace control harness.

Replace blower and motor.

Replace switch.

Check for low voltage, less than 102 vac., have service checked
and repaired.
If voltage is above 102 vac., make sure there is not more than 30 equivalent
feet (9.1 equivalent meters) of 3 inch pipe or 100 equivalent feet (30.5
equivalent meters) of 4 inch pipe installed or vent terminal blockage.
If at least 102 vac., less than 30 equivalent feet (9.1 equivalent
meters) of 3 inch pipe or 100 equivalent feet (30.5 equivalent meters)
of 4 inch pipe and not terminal blockage, replace blower.

Replace switch.

Replace gas valve.

Replace harness.
Replace igniter.

Reset cycle by turning switch off and then back on. If unit
does not light in thre e trials, call an authorized service
representative.
Verify dilution air openings are free of obstructions.
Make sure there is no more than 30 equivalent feet (9.1 equivalent meters) of
3 inch pipe or 100 equivalent feet (30.5 equivalent meters) of 4 inch pipe.
Check for low voltage, less than 102 vac., have service checked
and repaired.
Make sure vent terminal is not blocked.

Turn temperature control higher.
Replace thermostat.

Replace.

Reduce hot water use.
Contact an authorized service representative.
Allow more time for heater to re-heat.
Have plumber check and repair leaks.
Correct wiring
Correct
Take unit out of service immediately, call an authorized service
representative.
Proper air circulation must be provided for combustion and
dilution of ue temp. Refer to “INSTALLATION” section.
Room air to be used for dilution with combustion products in
ue should be less than 90°F.
Install correct orice.
Turn off heater and gas, clean burner head.
Clear area around heater and check under heater, remove any
debris under heater and in openings in bottom cover.
Refer to installation manual - Conned and Unconned Space
statements on page 4 and 5 for required openings.
See “CONDENSATION.”

Turn off heater & water, repair unit.

Inspect other appliances near water heater.

Refer to “CONDENSATION.”
Install thermal expansion tank (DO NOT plug T&P valve).
Check relief valve for proper operation (DO NOT plug T&P valve).
Drain and ush heater thoroughly, chlorinate, rell and ush again

then chlorinate water supply.

Test polarity and correct.

WARNING: DO NOT BY-PASS ANY CONTROLS TO MAKE HEATER OPERATE.

OPERATE ONLY AS WIRED FROM FACTORY.

TROUBLESHOOTING

Please check guidelines below. For your safety, water heater service should be performed only by a qualied service technician.

Read the GENERAL SAFETY INFORMATION section rst.

PROBLEM SOLUTION
An open earth ground circuit to the 1. Check that the earth ground connection is

ignition system. properly connected.

LED STATUS

B C D E F

2. Check that the ground conductor on the
water heater is properly connected.

Wiring error or a high resistance to 1. Check for proper connection of line
earth ground. neutral and hot wires.

B C D E F

2. Check that the water heater is securely
connected to earth ground.

Pressure switch remained closed longer 1. Pressure switch wiring is incorrect.
than 5 seconds after the call for 2. Replace pressure switch.

B C D E F

heat began.

Pressure switch remained open longer 1. Pressure switch wiring is incorrect.
than 5 seconds after the combustion 2. Pressure switch tubing not connected

B C D E F

blower was energized. correctly.

3. Air intake or exhaust obstructed.

Error in the hot surface ignitor circuit. 1. Check that all wiring is correct and secure.

B C D E F

2. Replace hot surface ignitor.

System in lockout. 1. Gas supply is off or too low to operate.

2. Hot surface ignitor not positioned

correctly.

B C D E F

3. Low voltage to the water heater.

4. Electric polarity to unit is incorrect - test

and correct.

Problem in the gas valve driver circuit. 1. Turn power to the water heater off for
10 seconds and then back on.

B C D E F

2. Replace gas control valve.

WATER HEATER CONTROL

Problem with the internal circuit. 1. Turn power to the water heater off for
10 seconds and then back on.

B C D E F

2. Replace gas control valve.

Problem with the internal circuit. 1. Turn power to the water heater off for
10 seconds and then back on.

B C D E F

2. Replace gas control valve.

Flame signal sensed out of 1. Replace gas control valve.

B C D E F

proper sequence.

ECO activated. 1. Lower water temperature to below 120°F
and turn power to the water heater off for

B C D E F

10 10 seconds and then back on.

2. Replace gas control valve.

One of the temperature adjust 1. Press and release each of the buttons once.

B C D E F

buttons stuck closed. 2. Replace gas control valve.

Water temperature sensor is 1. Check that all wiring is correct and secure.

B C D E F

either open or short circuited. 2. Replace gas control valve.

20

NOTES:

21

NOTES:

22

NOTES:

23

Model BTF Limited Warranty

A. O. Smith Corporation, the warrantor, extends the following LIMITED WARRANTY to the owner of this water heater.

1. THE TANK

If the glass-lined tank in this water heater shall prove upon examination by the warrantor to have leaked due to natural corrosion from potable

water therein, during the rst THREE years after initial installation, the warrantor will supply a complete new A. O. Smith water heater of equiva­lent size and current model. Some government agencies are requiring energy efcient standards for water heaters. In the event regulations
prohibit sale of a model of equivalent size and construction, A. O. Smith will provide a model which complies with the regulations of your area,
in which case the consumer will be charged the difference in price between the like replacement and the energy efcient model required. The
warranty on the replacement water heater will be limited to the unexpired term of the original warranty.

2. ALL OTHER PARTS

If within ONE year after initial installation of this water heater, any part or portion shall prove upon examination by the warrantor to be defective

in material or workmanship, the warrantor will repair or replace such part or portion at its option.

3. CONDITIONS AND EXCEPTIONS

This warranty shall apply only when the water heater is installed in accordance with local plumbing and building codes, ordinances and regulations,

the printed instructions provided with it and good industry practices. In addition, a temperature and pressure relief valve, certied by and ofcially

sanctioned and recognized independent testing agency and approved by the American Society of Mechanical Engineers, must have been installed.
a. This warranty shall apply only when the heater is:
(1) used at temperatures not exceeding the maximum calibrated setting of its thermostat;
(2) used at water pressure not exceeding the working pressure shown on the heater;
(3) lled with potable water, free to circulate at all times and with the tank free of damaging water sediment or scale deposits;
(4) used in a non-corrosive and non-contaminated atmosphere;
(5) used with factory approved anode(s) installed;
(6) in its original installation location;
(7) in the United States, its territories or possessions, and Canada;
(8) sized in accordance with proper sizing techniques for commercial and/or residential water heaters;
(9) bearing a rating plate which has not been altered, defaced or removed, except as required by the warrantor;
(10) operated with properly installed dirt leg;
(11) red with the fuel for which it was factory built;
(12) red at the factory rated input;
b. Any accident to the water heater, any misuse, abuse (including freezing or thermal expansion damage) or alteration of, any operation in

a modied form, or any attempt to repair tank leaks will void this warranty.
c. This warranty is void if a device acting as a backow prevention device (check valves etc.) is installed in the cold water supply the heater

4. SERVICE AND REPAIR EXPENSES

Under the limited warranty the warrantor will provide only a replacement water heater or part thereof. The owner is responsible for all other

a. Labor charges for service removal, repair or reinstallation of the water heater or any component part;
b. Shipping, delivery, handling, and administrative charges for forwarding the new heater or replacement part from the nearest distributor

c. All cost necessary or incidental for any material and/or permits required for installation of the replacement heater or part.

is connected to, unless an effective method of controlling thermal expansion is also installed at the heater(s) and operational at all times.
The relief valve installed on the heater is not an acceptable method.

costs. Such costs may include but are not limited to:

and returning the claimed defective heater or part to such distributor.

5. LIMITATIONS ON IMPLIED WARRANTIES

Implied warranties, including the warranty of merchantability imposed on the sale of this heater under state law are limited to one (1) year

duration for the heater or any of its parts. Some states or provinces do not allow limitation on how long an implied warranty lasts, so the above

limitation may not apply to you.

6. CLAIM PROCEDURE

Any claim under the warranty should be initiated with the dealer who sold the heater, or with any other dealer handling the warrantor’s products.

If this is not practicable, the owner should contact:
U.S. Customers Canadian Customers
A. O. Smith Water Products Company A. O. Smith Enterprises Ltd.
500 Tennessee Waltz Parkway P. O. Box, 310 - 768 Erie Street
Ashland City, TN 37015 Stratford, Ontario N5A 6T3
Telephone: [phone] Telephone: [phone]
a. The warrantor will only honor replacement with identical or similar water heater or parts thereof which are manufactured or distributed by

b. Dealer replacements are made subject to in-warranty validation by warrantor.

7. DISCLAIMERS

NO OTHER EXPRESS WARRANTY HAS BEEN OR WILL BE MADE IN BEHALF OF THE WARRANTOR WITH RESPECT TO THE MERCHANTABILITY

a. Some states and provinces do not allow the exclusion or limitation of the incidental or consequential damage, so the above limitations or

b. This warranty gives you specic legal rights, and you may also have other rights which vary from state to state or province to province.

Fill in the following for your own reference. Keep it. Registration is not a condition of warranty. The model and serial number are found on the heater’s

rating plate.

Model No. _________________________________ Serial No. _________________________________ Date Installed ___________________
Dealer's Name _______________________________________________________________________________________________________
Dealer's Address __________________________________________________________________ Phone No. _________________________
City and State/Province ______________________________________________________________________Zip/Postal Code _____________

the warrantor.

OF THE HEATER OR THE INSTALLATION, OPERATION, REPAIR OR REPLACEMENT OF THE HEATER. THE WARRANTOR SHALL NOT BE

RESPONSIBLE FOR WATER DAMAGE, LOSS OF USE OF THE UNIT, INCONVENIENCE, LOSS OR DAMAGE TO PERSONAL PROPERTY OR

OTHER CONSEQUENTIAL DAMAGE. THE WARRANTOR SHALL NOT BE LIABLE BY VIRTUE OF THIS WARRANTY OR OTHERWISE FOR

DAMAGE TO ANY PERSONS OR PROPERTY, WHETHER DIRECT OR INDIRECT, AND WHETHER ARISING IN CONTRACT OR IN TORT.

exclusions may not apply to you.

KEEP THIS WARRANTY POSTED ADJACENT TO THE HEATER FOR FUTURE REFERENCE.

24