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RESIDENTIAL GAS WATER HEATERS
OWNER'S MANUAL
Thank you for b uying this energy efficient water heater from
A.O. Smith Water Products Company. We appreciate your
confidence 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
GAS
PAG E
GET TO K NOW YOUR WATER HEATER 2
GENERAL SAFETY INFORMATION 3
INSTALLATION 4 -6
OPERATION 6 -8
MAINTENANCE AND
TROUBLESHOO TING 8 -10
W ARRANTY 11
CAUTION
TEXT PRINTED OR OUTLINED IN RED CONTAINS
INFORMATION RELATIVE TO YOUR SAFETY.
PLEASE READ THOROUGHLY BEFORE
INSTALLING AND USING THIS APPLIANCE.
KEEP THIS MANUAL IN THE POCKET ON HEATER FOR FUTURE REFERENCE
WHENEVER MAINTENANCE ADJUSTMENT OR SERVICE IS REQUIRED.
PRINTED IN U.S.A. 2460 1299
A DIVISION OF A.O. SMITH CORPORATION
www.hotwater.com
PART NO. 183390-000
1
SUPERSEDES PART NO. 183285-000
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GET TO KNOW Y OUR W A TER 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 A.O. Smith Water Products
Company, 5621 W. 115th Street, Alsip, Illinois 60803, 1-800-433-
2545. When ordering parts, provide complete model and serial
numbers (see rating plate), quantity and name of part desired (as
listed in Figure 1). Standards hardware items may be purchased
locally.
INSTALL THERMAL EXPANSION
TANK IF CHECK VALVE OR
PRESSURE REDUCING VALVE
IS USED IN SUPPLY
(A) VENT PIPE
(B) DRAFT HOOD
(C) ANODE
(D) HOT WATER
OUTLET
(E) OUTLET
(F) INSULATION
(G) GAS SUPPLY
(H) MANUAL GAS SHUT
OFF VALV E
(J) GROUND JOINT UNION
(K) DIRT LEG
(L) HINGED INNER DOOR
(M) OUTER DOOR
(N) UNION
(O) INLET WATER SHUT OFF
VA LVE
(P) COLD WATER INLET
(Q) INLET DIP TUBE
(R) TEMPERATURE AND
PRESSURE RELIEF VA LVE
(S) RATING PLATE
(T) FLUE BAFFLE
(U) THERMOSTAT
(V) DRAIN VALVE
(W) PILOT AND MAIN BURNER
(X) FLUE
(Y) DRAIN PAN
(Z) THERMOSTAT SHIELD
(OPTIONAL)
DIRTLEG AS
REQUIRED
BY LOCAL CODE
GAS MODELS
(W)
PILOT &
MAIN BURNER
FIGURE 1
2
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GENERAL SAFETY
INFORMATION
EXTERNAL DAMAGE
Do not operate the water heater until it has been fully checked out
by a qualified technician, if the water heater:
• Has been exposed to fire or damage.
• Displays evidence of sooting.
• Produces steam or unusually hot water.
If the water heater has been flooded it must be replaced.
CHEMICAL VAPOR CORROSION
pected, do not attempt to find 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 Y OU EXPERIENCE AN OUT-OF-GAS SITUATION, DO NOT TRY
TO RELIGHT APPLIANCES Y OURSELF. Ask your LP delivery person to relight pilots for you. Only trained LP professional should
conduct the required safety checks in accordance with industry standards.
WARNING
CORROSION OF THE FLUEWAYS AND VENT SYSTEM MAY
OCCUR IF AIR FOR COMBUSTION CONT AINS CER TAIN 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 warr anty is voided when
failure of water heater is due to a corrosive atmosphere. (Reference
is made to the limited warranty for complete terms and conditions).
IMPROPER COMBUSTION
WARNING
A TTIC AND/OR EXHA UST FANS OPERA TING 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 CHIMNEY OR VENT PIPE.
The venting of the water heater should be inspected by a qualified
service technician at the time of installation and periodically thereafter to ensure a down-draft condition does not exist.
DO NOT OBSTR UCT THE FLOW OF COMBUSTION AND VENTILATING AIR. ADEQUATE AIR FOR COMBUSTION AND VENTILATION MUST BE PROVIDED FOR SAFE OPERATION.
EXTENDED NON-USE PERIODS
W ARNING
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).
duce 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 flow. THERE SHOULD BE NO SMOKING OR
OPEN FLAME NEAR THE FAUCET AT THE TIME IT IS OPEN.
HYDROGEN GAS IS EXTREMELY FLAMMABLE. To re-
INSULATION BLANKETS
Insulation blankets available to the general public for external use
on gas water heaters are not necessary with A. O . Smith products.
The purpose of an insulation blanket is to reduce the standby heat
loss encountered with storage tank heaters. Your A. O . Smith water
heater meets or exceeds the National Appliance Energy Conservation Act standards with respect to insulation and standby loss requirements, making an insulation blanket unnecessary.
W ARNING
Should you choose to apply an insulation blanket to this heater,
you should follow these instructions (See Figure 1 for identification
of components mentioned below). Failure to follow these
instructions can restrict the air flow required for proper combustion,
potentially resulting in fire, asphyxiation, serious personal injury
or death.
Do not apply insulation to the top of the water heater, as this
•
will interfere with safe operation of the draft hood.
•
Do not cover the outer door, thermostat or temperature &
pressure relief valve.
LIQUID PETROLEUM MODELS
Water heaters for propane or liquefied 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.
LP gas must be used with great caution. It is highly explosive and
heavier than air. It collects first in the low areas making its odor
difficult to detect at nose level. If LP gas is present or even sus-
• Do not allow insulation to come within 2" of the floor to prevent
blockage of combustion air flow to the burner.
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 from A.O. Smith
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 flow.
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INSTALLATION
REQUIRED ABILITY
INSTALLATION OR SERVICE OF THIS WATER HEATER REQUIRES ABILITY EQUIVALENT TO THAT OF A LICENSED
TRADESMAN IN THE FIELD INVOLVED. PLUMBING, AIR SUPPLY, VENTING AND GAS SUPPLY ARE REQUIRED.
GENERAL
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 latest editions of the National
Fuel Gas Code, ANSI Z223.1/NFPA 54. The code is available from
the Canadian Standards Association, 8501 East Pleasant Valley
Road, Cleveland, OH 44131.
LOCATION OF HEATER
If the unconfined 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 draft hood dilution must be obtained from outdoors. The
installation instructions for confined spaces must be followed.
The heater is design certified by the American Gas Association for
installation on combustible flooring in a closet having minimum clearances from combustible material of: 0" clearance from sides and
rear, 4" from the front and 12" from the top . (Standard clear ance.) If
clearances stated on the heater differ from standard clearances,
install water heater according to clearances stated on heater.
A minimum clearance of 4" must be allowed for access to replaceable parts such as the thermostats, drain valve and relief valve.
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.
When installing the heater, consideration must be given to proper
location. Location selected should be as close to the stack or chimney as practicable with adequate air supply and as centralized with
the water piping system as possible.
W ARNING
For California installation this water heater must be braced,
anchored, or strapped to avoid falling or moving during an
earthquake. See instructions for correct installation procedures.
Instructions may be obtained from your local dealer, wholesaler,
public utilities or California's Office of the State Architect, 400 P
Street, Sacramento, CA 95814.
AIR REQUIREMENTS
In calculating the free area of a vent opening, the blocking effect of
screens, louvers and grills should be considered. Screens shall not
be of a mesh smaller than 1/4 inch square. If the free area is not
known, the latest edition of National Fuel Gas Code ANSI Z223.1
recommends using figures of 20-25 percent free area for wood louvers or 60-75 percent for metal grills or louvers.
UNCONFINED SPACE
In buildings of conventional frame, brick or stone construction, unconfined spaces may provide adequate air for combustion, ventilation, and draft hood dilution.
Installation:
Do not install water heater
where flammable products will
be stored or used unless the
main burner and pilot flames are
at least 18" above the floor . This
will reduce, but not eliminate, the
risk of vapors being ignited by
the main burner or pilot flame.
CONFINED SPACE
When drawing combustion and dilution air from inside a conventionally constructed building to a confined space, such a space shall
be provided with two permanent openings. ONE IN OR WITHIN 12
INCHES OF THE ENCLOSURE TOP AND ONE IN OR WITHIN 12
INCHES OF THE ENCLOSURE BO TTOM. Each opening shall hav e
a free area of at least one square inch per 1000 Btuh of the total
input of all appliances in the enclosure, but not less than 100 square
inches.
If the confined space is within a building of tight construction, air for
combustion, ventilation and draft hood 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 per 4000 Btuh 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 per 2000 Btuh of the total input of all appliances in the
enclosure.
CAUTION
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 HEA TER OR TO L O WER FLOORS
OF THE STRUCTURE. When such locations cannot be avoided,
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