A.O. Smith BPD-400 User Manual

AOS PREFERRE D-BPD 400 DIRE CT VENT

COMMERCIAL GAS W A TER HEA TER

GAS-FIRED INDUCED DRAFT
FOR DOMESTIC HOT W A TER

• INST ALLATION • OPERA TION • SER VICE • MAINTENANCE • LIMITED W ARRANTY

W ARNING: If the information in these
instructions is not followed exactly , a fire
or explosion may result causing property
damage, personal injury or death.

– Do not store or use gasoline or other

flammable 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
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 fire department.

– Installation and service must be

performed by a qualified installer,
service agency or the gas supplier .

Thank you for buying this energy efficient water heater from
A.O. Smith Water Products Company. We appreciate your
confidence in our products.

CAUTION

TEXT PRINTED OR OUTLINED IN RED CONTAINS
INFORMATION RELATIVE TO YOUR SAFETY. PLEASE
READ THOROUGHLY BEFORE INSTALLING AND USING
THIS APPLIANCE.

PLACE THESE INSTRUCTIONS ADJACENT TO HEA TER AND

NOTIFY OWNER TO KEEP FOR FUTURE REFERENCE.

PRINTED IN U .S.A. 0206 Part Number 197279-000

1

A DIVISION OF A.O. SMITH CORPORATION

Mc BEE, SOUTH CAROLINA

ROUGH-IN DIMENSIONS

TOP

GAS V AL VE PIPING

BPD -400 3/4" NPT

FRONT

Input Capacity SHIPPING

BTU Gallon

Model (kw-Hr.) (Liters) "A" "B" " C" "D" "E" "F" "G" "H" "I " LINE STD ASME

BPD - 400 390,000 95 82.25 80.25 30.25 8.75 4 or 6 21.75 63.50 2.25 58.00 1.00 900 lbs. 1100 lbs.

(114.3) (360) (209) (204) (77) (22) vent (55) (161) (8 ) (147) (2.54) 408 Kg 499 Kg

Table 1. RECOVER Y CAPACITIES - NA TURAL GAS

Input Capacity

BTU Gallon 30 F 40 F 50 F 60 F 70 F 80 F 90 F 100 F 110 F 120 F 130 F 140 F

Model (kw-Hr.) (Liters) 17 C 22 C 28 C 33 C 39 C 44 C 50 C 56 C 61 C 67 C 72 C

BPD - 400 390,000 95 1316 987 789 658 564 493 439 395 359 329 304 282

(114.3) (360) (4981) (3735) (2988) (2490) (2135) (1868) (1660) (1494) (1358) (1245) (1149) (1067)

DIMENSIONS IN INCHES (CM)

GAS WEIGHT

TEMPERA TURE RISE - DEGREES F - GALLONS PER HOUR (LPH)

78 C

Recovery capacities are based on heater performance at 83.5% thermal efficiency.

2

TYPICAL INST ALLATION

INTAKE FOR

COMBUSTION AIR

VENT TO

OUTDOORS

FLUE PRODUCTS
DISCHARGE PIPE

AIR INTAKE PIPE

TEMPERA TURE

PRESSURE RELIEF

VALVE

V ACUUM RELIEF REQUIRED BY SOME

CODES (REFER TO LOCAL CODES)

SHUTOFF V ALVE

COLD WA TER INLET

MIXING VALVE *

TEMPERED

WA TER OUTLET

HOT WA TER OUTLET

GAS

SUPPL Y

Installation Information: for Model BPD 400 100 Series

ELECTRICAL CLEARANCES PRESSURES ORIFICES INPUT

120/24VAC 60Hz 5A FRONT SIDES TOP NATURAL NATURAL NA TURAL 390kbtuh

UNIT IS POLARITY SENSITIVE 6" = (15 cm) 0 " 12 "= (30.5 cm) Manifold 4.50" WC Sea Level 0.126

Inlet 7.00" WC 4500' 0.126

Max. Inlet 14.00" WC 8000' 0.106

3

FOREWORD

These designs comply with the current version of the American National
Standard for Gas Water Heaters, Volume III, ANSI Z21.10.3 / CSA 4.3 as
automatic circulating tank water heaters, and automatic storage water
heaters.

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

Particular attention should be given to the installation of thermometers at
the locations indicated on the diagrams as these are necessary for checking
the proper functioning of the heater.

TABLE OF CONTENTS

PAGE PAGE

ROUGH-IN DIMENSIONS ................................................................... 2

TYPICAL INST ALLA TION .................................................................. 3

FOREWARD ...................................................................................... 4

GENERAL SAFETY INFORMA TION .................................................. 5

Precautions .................................................................................. 5

Chemical Vapor Corrosion........................................................... 5

Improper Combustion ................................................................... 5

Extended Nonuse Periods ........................................................... 5

Insulation Blankets ....................................................................... 5

High Altitude Installations ............................................................. 5

FEATURES ........................................................................................ 6

The Eliminator ............................................................................... 6

High Limit Switch (E.C.O.) ............................................................ 6

Circulating Pump........................................................................... 6

Dishwashing Machine Requirement ............................................ 6

Electronic Ignition Control ............................................................. 7

Pilot Assembly .............................................................................. 7

Gas Valve ..................................................................................... 7

Pressure Switch .......................................................................... 7

Step Down Transformer .............................................................. 8

Burner Tray Assembly ................................................................. 8

Burner Tray .................................................................................. 8

Burner .......................................................................................... 8

Burner Orifice .............................................................................. 8

Blower Assembly......................................................................... 8

High Limit Switch .......................................................................... 9

Shroud Assembly ......................................................................... 9

Temperature and Pressure Release Valve ................................. 9

INSTALLA TION INSTRUCTIONS ........................................................ 9

Required Ability ............................................................................ 9

Hard Water ................................................................................... 9

Locating the Heater...................................................................... 9

Leveling ........................................................................................ 9

Clearances ................................................................................... 10

Alcove Installation ........................................................................ 10

Air Requirements ......................................................................... 10

COMBUSTION AIR AND EXHAUST ................................................... 10

Venting Clearances ...................................................................... 10

Facts to Consider About the Location......................................... 11

Wire Fence ................................................................................... 11

Water Piping ................................................................................. 12

Temperature-Pressure Relief Valve ............................................ 12

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.

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 Electric Code. The former is available from the Canadian Standards
Association, 8501 East Pleasant Valley Road, Cleveland, OH 44131, and
both documents are available from the National Fire Protection Association,
1 Batterymarch Park, Quincy, MA 02269.

Filling the Water Heater................................................................ 13

Wiring ........................................................................................... 13

Venting ......................................................................................... 15

Venting Through Roof.................................................................. 19

GAS PIPING ....................................................................................... 20

Sediment Trap .............................................................................. 20

INST ALLATION CHECKLIST .............................................................. 21

Operating Instructions for Model 100-400 .................................. 22

Operational Sequence (Natural Gas Models Only) ..................... 22

Safety Sequence (Natural Gas Models Only) ............................. 22

Robertshaw Control System (Natural Gas) ................................ 22

FOR YOUR SAFETY......................................................................... 23

Operating Instructions ................................................................. 23

To Turn Off Gas to Appliance ...................................................... 23

T emperature Regulation ............................................................... 24

Temperature Adjustments ............................................................ 24

STAR T UP CONDITIONS.................................................................... 24

Condensation ............................................................................... 24

Smoke/Odor.................................................................................. 25

Thermal Expansion....................................................................... 25

Strange Sounds ........................................................................... 25

OPERATIONAL CONDITIONS ............................................................ 25

Smelly Water ................................................................................ 25

Air in Hot Water Faucets ............................................................. 25

Venting Manual Reset Switch...................................................... 25

High Temperature Shut Off System ............................................. 25

E.C.O. ........................................................................................... 25

Not Enough or No Hot Water........................................................ 25

Water Is Too Ho t ........................................................................... 26

Venting System Inspection .......................................................... 26

Burner Inspection ......................................................................... 26

Burner Cleaning ........................................................................... 26

Housekeeping .............................................................................. 27

Draining ........................................................................................ 27

Service ......................................................................................... 27

INSTALLA TION DIAGRAMS .............................................................. 28

Manifold Kits................................................................................. 33

Sediment Removal........................................................................ 34

Lime Scale Removal ..................................................................... 34

Anode Inspection and Replacement............................................ 34

Replacement Parts ....................................................................... 34

MODEL BPD 400 LIMITED WARRANTY............................................ 35

4

GENERAL SAFETY INFORMATION

PRECAUTIONS

DO NOT USE THIS APPLIANCE IF ANY P AR T HAS BEEN UNDER WATER.
Immediately call a qualified service technician to inspect the appliance
and to replace any part of the control system and any gas control
which has been under water.

IF THE UNIT IS EXPOSED TO THE FOLLOWING, DO NOT OPERATE
HEATER UNTIL ALL CORRECTIVE STEPS HAVE BEEN MADE BY A
QUALIFIED SERVICEMAN.

1. EXTERNAL FIRE.

2. DAMAGE.

3. FIRING WITHOUT WA TER.

4. SOOTING.

CHEMICAL VAPOR CORROSION

DANGER

CORROSION OF THE FLUE AND VENT SYSTEM MAY OCCUR IF AIR
FOR COMBUSTION CONTAINS CERTAIN CHEMICAL VAPORS. SUCH
CORROSION MAY RESUL T IN F AILURE AND RISK OF ASPHYXIA TION.

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. (Refer to the limited warranty for complete terms and
conditions.)

SERVED BY THIS HEA TER THA T HAS NOT BEEN USED FOR A LONG
PERIOD OF TIME (GENERALL Y TWO WEEKS OR MORE). HYDROGEN
GAS IS EXTREMELY FLAMMABLE.

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 A T THE TIME IT IS OPEN.

To reduce the risk of injury under

INSULA TION BLANKETS

Insulation blankets available to the general public for external use on
gas water heaters are not approved for use on your A.O. Smith water
heater. The purpose of an insulation blanket is to reduce the standby
heat loss encountered with storage tank water heaters. Your A.O.Smith
water heater meets or exceeds the ASHRAE/IES 90.1b-1999 standards
with respect to insulation and standby loss requirement making an
insulation blanket unnecessary.

DANGER

Should you choose to apply an insulation blanket to this heater,
you should follow these instructions. Failure to follow these
instructions can result 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 venting components.

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

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

• Do not allow insulation to come within 2" (5 cm) of the burners, to
prevent blockage of combustion air flow to the burners.

• Do not allow insulation to come within 9" (23 cm) of floor, (within 2"
(5cm) of bottom cover) to prevent blockage of combustion air flow
to the burners.

IMPROPER COMBUSTION

DANGER

A TTIC AND/OR EXHAUST FANS OPERA TING ON THE PREMISES WITH A
WA TER HEA TER CAN RESUL T IN CARBON MONOXIDE POISONING AND
DEATH.

OPERATION OF THESE F ANS CAN PRODUCE A NEGA TIVE 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 OBSTRUCT THE FLOW OF COMBUSTION AND VENTILA TING AIR.
ADEQUATE AIR FOR COMBUSTION AND VENTILATION MUST BE PROVIDED
FOR SAFE OPERATION.

EXTENDED NONUSE PERIODS

DANGER

HYDROGEN GAS CAN BE PRODUCED IN A HOT WATER SYSTEM

• Do inspect the insulation blanket frequently to make sure it does not
sag, thereby obstructing combustion air flow.

• Do obtain new labels from A.O. Smith for placement on the blanket
directly over the existing labels.

HIGH ALTITUDE INSTALLATIONS

DANGER

INSTALLATIONS ABOVE 2000 FEET (610 METERS) REQUIRE
REPLACEMENT OF THE BURNER ORIFICES IN ACCORDANCE WITH
SECTION 8.1.2 OF THE NATIONAL FUEL GAS CODE (ANSI Z223.1).
FAILURE TO REPLACE THE ORIFICES WILL RESUL T IN IMPROPER AND
INEFFICIENT OPERATION OF THE APPLIANCE RESULTING IN THE
PRODUCTION OF INCREASED LEVELS OF CARBON MONOXIDE GAS IN
EXCESS OF SAFE LIMITS WHICH COULD RESUL T IN SERIOUS PERSONAL
INJURY OR DEA TH.

You should contact your gas supplier for any specific changes which
may be required in your area.

As elevation above sea level is increased, there is less oxygen per cubic

5

foot of air. Therefore, the heater input rate should be reduced at high
altitudes for satisfactory operation with the reduced oxygen supply.
Failure to make this reduction would result in an over-firing of the
heater causing sooting, poor combustion and/or unsatisfactory heater
performance.

Ratings specified by manufacturers for most appliances apply for
elevations up to 2000 feet (610 m). For elevations above 2000 feet
(610), ratings must be reduced at the rate of 4% for each 1000 feet
(305m) above sea level. For example, if a heater is rated at 120,000
Btuh (35 Kwh) at sea level, to rate the heater at 4000 feet (1219 m),
you subtract 4 (once for each thousand feet) x 04 (4% input reduction)
x 120,000 (original rating) from the original rating. Therefore, to
calculate the input rating at 4,000 feet (121.9 m): 4 x .04 x 120,000 =
19,200 Btuh (5.6 Kwh), 120,000 (35 Kwh) - 19,200 (5.6 Kwh) = 100,800
Btuh (29.4 Kwh). At 6000 feet (1829 m) the correct input rating should
be 91,200 Btuh (26.7 Kwh).

Field conversion is not permitted.

FEATURES

THE ELIMINA T OR

(SELF-CLEANING S YSTEM)

• A malfunction in the thermostatic controls could allow the gas valve
to remain open causing water temperature to exceed the
thermostat setting. The water temperature would continue to rise
until high limit switch operation.

Contact your dealer or servicer if continued high limit switch operation
occurs.

These units include The Eliminator (Self-Cleaning System) installed in
the front water inlet, see Figure 2. The Eliminator must be oriented
correctly for proper function. There is a marked range on the pipe
nipple portion of the Eliminator, that must be aligned with the top of the
inlet spud. A label above the jacket hole has an arrow that will point to
the marked portion of the pipe nipple if the orientation is correct. If the
arrow does not point within the marked range on the pipe nipple,
adjust the pipe nipple to correct. A pipe union is supplied with the
Eliminator to reduce the probability of misaligning the Eliminator
accidentally while tightening the connection to the inlet water supply
line. Improper orientation of the Eliminator can cause poor performance
of the heater and can significantly reduce outlet water temperatures
during heavy draws.

FIGURE 1

HIGH LIMIT SWITCH (E.C.O.)

The dual bulb controller contains the high limit (energy cutoff) sensor,
see Figure 2. The high limit switch interrupts main burner gas flow
should the water temperature reach 205°F (96°C).

DUAL-BULB THERMOST AT

(SHOWN AT TOP WITH COVER ON AND AT BOTTOM

WITH COVER REMOVED)

FIGURE 2

Continued pilot outage preceded by higher than usual water temperature
is evidence of high limit switch operation. Contact your dealer or
servicer to determine the reason for operation.

CIRCULATING PUMP

A circulating pump is used when a system requires a circulating
loop or there is a storage tank used in conjunction with the heater.
Refer to the piping diagrams in this manual for electrical hookup
information and install in accordance with the current version of
the National Electric Code ANSI/NFPA No. 70.

Only all bronze circulators are used with commercial water heaters.

Although circulators are oiled and operated by the manufacturer some
circulators must be oiled again before operating. Please refer to
manufacturer’s instructions.

In the event of high limit switch operation, the appliance cannot be
restarted unless the water temperature is reduced by at least 20°F
(11°C) and the high limit reset button on front of limit control is depressed,
see Figure 2.

Continued manual resetting of high limit control, preceded by higher
than usual water temperature is evidence of high limit switch operation.
The following is a possible reason for high limit switch operation.

DISHWASHING MACHINE REQUIREMENT

These appliances meet the National Sanitation Foundation St andard for
sanitary installations when used with the following leg kits, Part No’s.
6570-0 and 6570-7.

All dishwashing machines meeting the National Sanitation Foundation
requirements are designed to operate with water flow pressures

6

between 15 and 25 psi (103 kPa and 173 kPa). Flow pressures above 25
psi (173 kPa), or below 15 psi (103 kPa), will result in improperly sanitized
dishes. Where pressures are high, a water pressure reducing or flow
regulating control valve should be used in 180°F (82°C) line to the
dishwashing machine, and should be adjusted to deliver water between
these limits.

The National Sanitation Foundation also recommends circulation of 180°F
(82°C) water. Where this is done, the circulation should be very gentle so
that it does not cause any unnecessary turbulence inside the water
heater. The circulation should be just enough to provide 180°F (82°C)
water at the point of takeoff to the dishwashing machine. Adjust flow by
means of the plug cock in the circulating line.

FIGURE 3

ROBERTSHAW SP715A IGNITION CONTROL MODULE

NATURAL GAS MODEL

ROBERT SHA W 47484A PILO T SENSOR

ROBERTS HA W DERHC-S7C NA TURAL 1" x 1" GAS V AL VE

ELECTRONIC IGNITION CONTROL

Each heater is equipped with an ignition control module (See figure 3
above). The solid state ignition control ignites the pilot burner gas by
creating a spark at the pilot assembly. Pilot gas is ignited and burns
during each running cycle. The main burner and pilot gases are cut off
during the OFF cycle. Pilot operation is proven by the pilot sensor.
Main burner ignition will not occur if the pilot sensor does not first
sense pilot operation.

PILOT ASSEMBL Y

The pilot assembly is mounted between the two middle burner
assemblies in the combustion chamber. The ignition sequence begins
with the ignition module sending voltage to the sparker located on the
front side of the pilot hood. Pilot gas flow is initiated after the sparker
begins to spark. The spark across the pilot gas flow ignites the pilot
gas. Once the pilot gas is ignited, the flame sensor senses the flame
through flame rectification (which means that the module's signal
changes from an AC current to a DC current because the current can
now flow through the flame to the pilot hood which is grounded to the
unit). Once the sensor senses flame, the signal is sent back to the
module to open up the gas valve for the main burners.

GAS VALVE

The gas valve is used to supply the gas to the unit during heat up periods.
The ignition control module monitors the thermostat's call for heat and
sends a signal to the gas valve when to open to allow gas flow.

PRESSURE SWITCH

The Blocked Outlet/Prover switch is set up to shut the unit off when a
pressure buildup in the exhaust vent pipe occurs. This switch is a
negative pressure switch that requires an increase in negative pressure
to change the electrical contacts from normally open to closed. The
switch is connected to the pressure tap connected to the housing of
the blower. When this switch prevents the unit from ignition, most
likely the exhaust is blocked by some means. Check for obstructions
in the exhaust vent terminal.

The Blocked Outlet/Prover switch has a second function. It is provided
on the heater to verify that the fan is operating. When the fan increases
in negative pressure, the electrical contacts close signaling that the
blower is operational and is at peak performance. The controller
requires that the electrical contacts on the switch close before it will

allow the burners to operate.

ROBERT SHA W #6S24-6 PILO T ASSEMBLY

MPL 9300VO AIR PRESSURE SWITCH

7

STEP DOWN TRANSFORMER

BURNER

The controls system utilizes a 120/24 VAC step down transformer.
Most of the control system utilizes 24 VAC for operation. See wiring
diagram for those components utilizing 24 VAC and 120 VAC.

P120/24 V AC STEP DOWN TRANSFORMER

BURNER TRA Y ASSEMBLY

The appliance is equipped with a user friendly burner tray assembly.
The assembly consists of a burner tray for mounting the burners,
manifold and orifices along with the gas valve and pilot assembly. It
can be easily removed by sliding the assembly in and out like a drawer
due to slide mounts in the combustion chamber.

The appliance is equipped with 8 burners mounted in a burner tray
assembly. The burners are tubular in design with two rows of small slit
burner ports. The natural gas burners are made of aluminized steel and
the LP version is a stainless steel material.

TUBULAR BURNER ASSEMBL Y

BURNER ORIFICE

The burner orifice regulates the input to the main burners.

BURNER TRAY ASSEMBL Y - NATURAL

BURNER TRA Y

The burner tray holds the burners in place and is used to slide the
entire assembly into the combustion chamber.

BURNER TRAY

BURNER ORIFICE

BLOWER ASSEMBL Y

The blower assembly functions by pulling in air from the outside of the
unit to supply the main burners located in the combustion chamber for
proper combustion. The blower pulls the air through the combustion
chamber and flue tubes where the flue gases then exit the exhaust vent.

FASCO BLOWER ASSEMBLY

8

HIGH LIMIT SWITCH

INSTALLATION INSTRUCTIONS

The surface mounted high limit switch monitors the flue gases escaping
through the blower assembly to ensure the temperatures do not exceed
the rating for the CPVC/PVC vent pipe utilized on the venting.

FIGURE 4

HIGH LIMIT SWITCH

SHROUD ASSEMBL Y

The shroud assembly protects the top of the appliance where the blower
and junction box are located.

SHROUD ASSEMBL Y

TEMPERA TURE AND PRESSURE RELIEF V AL VE

The temperature and pressure relief valve is a mechanical valve that
will open when the temperature or pressure in the tank exceeds
safe limits.

REQUIRED ABILITY

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

WARNING

FAILURE TO FOLLOW THESE INSTRUCTIONS CAN RESUL T IN SERIOUS
PERSONAL INJURY OR DEA TH.

HARD W A TER

Where hard water conditions exist, water softening or the threshold type
of water treatment is recommended. This will protect the dishwashers,
coffee urns, water heaters, water piping and other equipment.

See MAINTENANCE section for details of tank clean out procedure.

LOCA TING THE HEA TER

When installing the heater, consideration must be given to proper
location with adequate air supply and as centralized with the piping
system as possible.

WARNING

THERE IS A RISK IN USING FUEL BURNING APPLIANCES SUCH AS GAS
WATER HEATERS IN ROOMS, GARAGES OR OTHER AREAS WHERE
GASOLINE, OTHER FLAMMABLE LIQUIDS OR ENGINE DRIVEN EQUIPMENT
OR VEHICLES ARE ST ORED, OPERA TED OR REP AIRED. FLAMMABLE
VAPORS ARE HEAVY AND TRAVEL ALONG THE FLOOR AND MAY BE
IGNITED BY THE HEA TER’S PILOT OR MAIN BURNER FLAMES CAUSING
FIRE OR EXPLOSION. SOME LOCAL CODES PERMIT OPERA TION OF GAS
APPLIANCES IN SUCH AREAS IF THEY ARE INSTALLED 18” OR MORE
ABOVE THE FLOOR. THIS MA Y REDUCE THE RISK IF LOCA TION IN SUCH
AN AREA CANNOT BE AVOIDED.

DO NOT INST ALL THIS W ATER HEA TER DIRECTL Y ON A CARPETED FLOOR. A
FIRE HAZARD MA Y 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, the entire floor
shall be covered by the panel. Also, see the DRAIN REQUIREMENTS.

THE HEA TER SHALL BE LOCA TED OR PROTECTED SO IT IS NOT SUBJECT
TO PHYSICAL DAMAGE BY A MOVING VEHICLE.

TEMPERATURE AND PRESSURE RELIEF V AL VE

DRAIN VAL VE

The drain valve is used to drain the unit of water for servicing or replacement.

DRAIN V AL VE

WARNING

FLAMMABLE ITEMS, PRESSURIZED CONTAINERS OR ANY OTHER

POTENTIAL FIRE HAZARDOUS ARTICLES MUST NEVER BE PLACED ON
OR ADJACENT TO THE HEATER. OPEN CONTAINERS OR FLAMMABLE
MATERIAL SHOULD NOT BE STORED OR USED IN THE SAME ROOM WITH
THE HEATER. THE HEA TER MUST NOT BE LOCA TED IN AN AREA WHERE IT
WILL BE SUBJECT TO FREEZING . LOCA TE IT NEAR A FLOOR DRAIN. THE
HEATER SHOULD BE LOCA TED IN AN AREA WHERE LEAKAGE FROM THE
HEATER OR CONNECTIONS WILL NOT RESULT IN DAMAGE TO THE ADJACENT
AREA OR TO LOWER FLOORS OF THE STRUCTURE.

WHEN SUCH LOCATIONS CANNOT BE A VOIDED, A SUIT ABLE DRAIN P AN
SHOULD BE INSTALLED UNDER THE HEATER. Such pans should be fabricated

with sides at least 2" (5 cm) deep, with length and width at least 2" (5 cm)
greater than the diameter of the heater and must be piped to an adequate
drain. The pan must not restrict combustion air flow.

For appliance installation locations with elevations above
2000 feet (610 m), refer to HIGH ALTITUDE INSTALLATIONS section of this
manual for input reduction procedure.

LEVELING

If the unit is not level, insert the bolts which were used in crating into the
legs to correct this condition.

9

CLEARANCES

The unit is approved for installation on combustible flooring in an alcove
when the minimum clearance to combustibles is maintained per Figure 6
and the table below.

ABCD

(RIGHT SIDE) (LEFT SIDE) (BACK) (CEILING)

0" (0cm) 0" (0cm) 0" (0cm) 12" (30.5 cm)

A service clearance of 24" (61 cm) should be maintained from serviceable
parts, such as relief valves, flue baffles, flue damper devices, thermostats,
cleanout openings or drain valves.

FIGURE 5

If the unconfined space is within a building of tight construction (buildings 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 in tightly constructed
buildings must be followed to ensure adequate air supply.

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 (30.5 cm)
OF THE ENCLOSURE TOP AND ONE IN OR WITHIN 12 INCHES (30.5 cm)
OF THE ENCLOSURE BOTTOM. Each opening shall have a free area of at
least one square inch per 1000 Btuh (2,225mm²/Kw) of the total input of
all appliances in the enclosure, but not less than 100 square inches (645
square cm).

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
with the outdoors 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 (8,900mm²/Kw) 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 (4,450mm²/Kw) of the total input of all appliances in the enclosure.

MECHANICAL EXHAUSTING OF ROOM AIR

Where an exhaust fan is installed in the same room with a heater, sufficient
openings for air must be provided in the walls. UNDERSIZED OPENINGS
WILL CAUSE AIR TO BE DRAWN INTO THE ROOM THROUGH THE HEATER'S
VENTING SYSTEM, CAUSING POOR COMBUSTION AND/OR SOOTING
WHICH MAY RESULT IN SERIOUS DAMAGE TO THE HEA TER AND RISK OF
FIRE OR EXPLOSION. IT CAN ALSO CREA TE A RISK OF ASPHYXIA TION.

FIGURE 6

ALCOVE INSTALLA TION (ACCEPT ABLE)

An alcove suitable for the installation of a water heater is a restricted
section of a room not separated from the room by a door or partition and
which meets the minimum clearances for the water heater.

*When the ceiling height exceeds 8 feet (2.4 m), you are only allowed to
consider 8 feet (2.4 m) when calculating the total volume of the enclosure.

AIR REQUIREMENTS

REFER TO THE CURRENT EDITION OF THE NA TIONAL FUEL GAS CODE
ANSI Z223.1/NFPA 54.

WARNING

KEEP APPLIANCE AREA CLEAR AND FREE OF COMBUSTIBLE MA TERIALS,
GASOLINE AND OTHER FLAMMABLES, V APORS AND LIQUIDS.

DO NOT OBSTRUCT THE FLOW OF COMBUSTION OR VENTILA TING AIR.

WARNING

FOR SAFE OPERA TION PROVIDE ADEQUA TE AIR FOR COMBUSTION AND
VENTILATION. AN INSUFFICIENT SUPPLY OF AIR WILL CAUSE
RECIRCULATION OF COMBUSTION PRODUCTS RESULTING IN AIR
CONT AMINATION THA T MAY BE HAZARDOUS TO LIFE. SUCH A CONDITION
OFTEN WILL RESUL T IN A YELLOW , LUMINOUS BURNER FLAME, CAUSING
CARBONING OR SOOTING OF THE COMBUSTION CHAMBER, BURNERS
AND FLUE TUBES AND CREA TES A RISK OF ASPHYXIA TION.

Where an exhaust fan is supplied in the same room with a heater, sufficient
openings for air must be provided in the walls. UNDERSIZED OPENINGS WILL

CAUSE AIR T O BE DRAWN INTO THE ROOM THROUGH THE CHIMNEY, CAUSING
POOR COMBUSTION. SOOTING MAY RESUL T IN SERIOUS DAMAGE TO THE

HEATER AND RISK OF FIRE OR EXPLOSION.

UNCONFINED SPACE

In buildings of conventional frame, brick, or stone construction, unconfined spaces
may provide adequate air for combustion, ventilation and draft hood dilution.

COMBUSTION AIR AND EXHAUST

WARNING

WHEN DETERMINING THE INSTALLATION LOCA TION FOR A POWER
DIRECT VENT WA TER HEA TER, SNOW ACCUMULA TION AND DRIFTING

SHOULD BE CONSIDERED IN AREAS WHERE APPLICABLE.

VENTING CLEARANCES

VENTING THROUGH AN OUTSIDE WALL-CLEARANCES

• 1" (2.5 cm) clearance for 4" or 6" PVC or CPVC piping from combustible

surfaces for outlet piping.

• 0" clearance for 4" or 6" PVC or CPVC piping from combustible surfaces

for inlet piping.

• 18" (46 cm) minimum in all directions from any obstruction, such as a wall,

that may interfere.

• 18" (46 cm) minimum from the ground and 9" from ceiling overhangs.

See Figure 7.

• The Power Direct Vent outlet terminal shall terminate a least 36" (91 cm)

above any forced air inlet located within 10 feet. See Figure 8.

• The Power Direct Vent outlet terminal shall terminate at least 36" (91 cm)

below, 36" (91 cm) horizontally from or 18" (46 cm) above any door,
window or gravity air inlet into the building. See Figure 8.

• 18" (46 cm) minimum from other natural draft (gravity) direct vent, power

vent or power direct vent appliance inlet and/or outlet vent(s) when directly
above or 135° to either side of center line. See Figure 9.

• 36" (91 cm) minimum from any appliance inlet and / or outlet vents when

directly below or 45° to either side of center line. See Figure 9.

• Vent termination must not be within 4 feet of any items such as gas

meters, gas valves or other gas regulating equipment.

• The venting system must be installed in a manner which allows inspection

of the installation of the venting pipes and joints as well as periodic
inspection after installation as required by ANSI Standards.

10

WARNING

THE LOCATION SELECTED MUST PROVIDE CLEARANCES FOR SERVICING
AND PROPER OPERATION OF THE W A TER HEA TER.

WARNING

VENT TERMINA TION MUST NOT BE WITHIN 4 FEET OF ANY ITEMS SUCH AS GAS
METERS, GAS VAL VES OR OTHER GAS REGULATING EQUIPMENT .

WARNING

FAILURE TO HAVE REQUIRED CLEARANCES BETWEEN W A TER HEA TER
AND COMBUSTIBLE MATERIAL WILL RESUL T IN A FIRE HAZARD.

FIGURE 9

WIRE FENCE

When the water heater outlet terminal is low enough to be touched
accidentally, or is accessible to small children, a wire mesh chain link
fence (as shown in Figure 9) may be used. Care should be taken to
maintain adequate ventilation around the outlet terminal. If a chain link
fence is installed, it must not be used as a storage area for items that

may block proper ventilation.

FIGURE 7

FACTS TO CONSIDER ABOUT THE LOCA TION

VENTING THROUGH ROOF-CLEARANCES

• 1" (2.5 cm) clearance for 4" or 6" PVC or CPVC piping from
combustible surfaces for outlet piping.

• 0" clearance for 4" or 6" PVC or CPVC piping from combustible
surfaces for inlet piping.

• The Power Direct Vent inlet and outlet terminals shall terminate at
least 18" (46 cm) above the roof surface. See Figure 10.

• The venting system must be installed in a manner which allows
inspection of the installation of the venting pipes and joints as well as

periodic inspection after installation as required by ANSI Standards.

FIGURE 9

FIGURE 8 - DIRECT VENT TERMINAL CLEARANCES - US INSTALLA TION

11

FIGURE 10

W ATER PIPING

WARNING

HOTTER WATER CAN SCALD: WATER HEATERS ARE INTENDED T O
PRODUCE HOT WA TER. W A TER HEA TED T O A TEMPERA TURE WHICH
WILL SATISFY CLOTHES WASHING, DISH WASHING, AND OTHER
SANITIZING NEEDS CAN SCALD AND PERMANENTL Y INJURE YOU
UPON CONTACT. SOME PEOPLE ARE MORE LIKELY TO BE
PERMANENTLY INJURED BY HOT WATER THAN OTHERS. THESE
INCLUDE THE ELDERL Y, CHILDREN, THE INFIRM, OR PHYSICALLY/
MENT ALL Y HANDICAPPED. IF ANYONE USING HOT W A TER IN YOUR
HOME FITS INTO ONE OF THESE GROUPS OR IF THERE IS A LOCAL
CODE OR ST A TE LA W REQUIRING A CERT AIN TEMPERA TURE W ATER
AT THE HOT WATER TAP, THEN YOU MUST TAKE SPECIAL
PRECAUTIONS. IN ADDITION TO USING THE LOWEST POSSIBLE
TEMPERA TURE SETTING THAT SA TISFIES YOUR HOT WA TER NEEDS,
A MEANS SUCH AS A MIXING VALVE, SHOULD BE USED AT THE
HOT WATER TAPS USED BY THESE PEOPLE OR AT THE WATER
HEATER. MIXING V AL VES ARE AVAILABLE A T PLUMBING SUPPLY
OR HARDWARE STORES. FOLLOW MANUFACTURERS
INSTRUCTIONS FOR INSTALLATION OF THE VALVES. BEFORE
CHANGING THE FACTORY SETTING ON THE THERMOSTAT, READ
THE "TEMPERATURE REGULATION" SECTION IN THIS MANUAL.

This water heater shall not be connected to any heating systems or
component(s) used with a non-potable water heating appliance.

If a water heater is installed in a closed water supply system, such as
one having a back-flow preventer, check valve, water meter with
check valve, etc... in the cold water supply, means shall be provided
to control thermal expansion. Contact the water supplier or plumbing
contractor on how to control this situation.

COMPL YING WITH THE STANDARD FOR RELIEF VA L VES AND HOT
WATER SUPPLY SYSTEMS, ANSI Z21.22. THE HOURLY RATED
TEMPERATURE STEAM BTU DISCHARGE CAPACITY OF THE
TEMPERATURE-PRESSURE RELIEF VAL VE(S) SHALL NOT BE LESS
THAN THE COMBINED BTU INPUT TO THE WATER HEATER(S)
SUPPL YING W ATER TO THE STORAGE VESSEL(S).

THERMOMETERS (Not Supplied)

Thermometers should be obtained and field installed as shown in the
installation diagrams.

Thermometers are installed in the system as a means of detecting the
temperature of the water in the appliance.

TEMPERATURE-PRESSURE RELIEF VALVE

This water heater is equipped with a combination temperature-pressure
relief valve that complies with the standard for relief valves and automatic
gas shutoff devices for hot water supply system, ANSI Z21.22. FOR

SAFE OPERA TION OF THE WATER HEATER, THE RELIEF VALVE(S)
MUST NOT BE REMOVED OR PLUGGED.

ASME ratings cover pressure relief capacities. A.G.A. ratings cover
release rate with temperature actuation.

In addition to the appliance relief valve, each remote storage tank which
may be used in conjunction with this appliance shall also be installed with
a properly sized, rated and approved combination temperature (ANSI)
and pressure (ASME) relief valve(s).

WARNING

THE PURPOSE OF RELIEF VALVE IS TO AVOID EXCESSIVE
PRESSURE OR TEMPERATURE INTO THE STEAM RANGE, WHICH
MA Y CAUSE SCALDING AT FIXTURES, T ANK EXPLOSION, SYSTEM
OR HEATER DAMAGE. NO V ALVE IS TO BE PLACED BETWEEN THE
RELIEF V AL VE AND TANK.

Your local code authority may have other specific relief valve
requirements.

A DRAIN LINE MUST BE CONNECTED TO THE RELIEF VALVE TO
DIRECT DISCHARGE TO A SAFE LOCATION TO AVOID SCALDING
OR WATER DAMAGE. THIS LINE MUST NOT BE REDUCED FROM
THE SIZE OF THE VALVE OUTLET AND MUST NOT CONT AIN VAL VES
OR RESTRICTIONS NOR SHOULD IT BE LOCATED IN FREEZING
AREAS. DO NOT THREAD OR CAP THE END OF THIS LINE.
RESTRICTED OR BLOCKED DISCHARGE WILL DEFEAT THE PURPOSE
OF THE VALVE AND IS UNSAFE. DISCHARGE LINE SHALL BE
INSTALLED TO ALLOW COMPLETE DRAINAGE OF BOTH THE V AL VE
AND LINE.

See SERVICE INFORMATION section for procedure and
precautions.

NOTE: To protect against untimely corrosion of hot and cold
water fittings, it is strongly recommended that dielectric
unions or couplings be installed on this water heater when
connected to copper pipe.

NOTE: If using copper tubing, solder tubing to an adapter
before attaching the adapter to the cold water inlet connection.
Do not solder the cold water supply line directly to the cold
water inlet. It will harm the dip tube and damage the tank.

WARNING

IF A WATER HEATER IS INSTALLED IN CONJUNCTION WITH A
SEP ARA TE STORAGE VESSEL, THE STORAGE VESSEL MUST ALSO
BE EQUIPPED WITH A TEMPERATURE-PRESSURE RELIEF VALVE

WARNING

THE TEMPERA TURE-PRESSURE RELIEF V AL VE MUST BE MANUALL Y
OPERATED A T LEAST ONCE A YEAR. CAUTION SHOULD BE TAKEN
TO ENSURE THAT (1) NO ONE IS IN FRONT OF OR AROUND THE
OUTLET OF THE TEMPERATURE-PRESSURE RELIEF VALVE
DISCHARGE LINE, AND (2) THE WATER MANUALLY DISCHARGED
WILL NOT CAUSE ANY BODILY INJURY OR PROPERTY DAMAGE
BECAUSE THE WATER MA Y BE EXTREMELY HOT .
IF AFTER MANUALLY OPERATING THE VALVE, IT FAILS TO
COMPLETELY RESET AND CONTINUES TO RELEASE WATER,
IMMEDIATELY CLOSE THE COLD WATER INLET TO THE WATER
HEATER, FOLLOW THE DRAINING INSTRUCTIONS, AND REPLACE
THE TEMPERATURE -PRESSURE RELIEF VAL VE WITH A NEW ONE.

12

If you are not familiar with electric codes and practices, or if you have
any doubt in your ability to connect the wiring to this water heater, contact
a local electrical contractor and/or the local electric utility.

WARNING

WATER HEATERS EQUIPPED FOR ONE TYPE VOLTAGE ONLY: THIS
WA TER HEA TER IS EQUIPPED FOR 1 10/120 VOL TS ONL Y. DO NOT USE
THIS WATER HEATER WITH ANY VOLTAGE OTHER THAN THE ONE
SHOWN ABOVE. F AILURE TO USE THE CORRECT VOL TAGE CAN CAUSE
PROBLEMS WHICH CAN RESUL T IN DEA TH, SERIOUS BODIL Y INJUR Y
OR PROPERTY DAMAGE. IF YOU HA VE ANY QUESTIONS OR DOUBTS
CONSULT YOUR ELECTRIC COMPANY.

CAUTION

IF WIRING FROM THE FUSE BOX OR CIRCUIT BREAKER BOX WAS
ALUMINUM FOR THE OLD WA TER HEA TER, REPLACE IT WITH COPPER
WIRE. IF YOU WISH TO REUSE THE EXISTING ALUMINUM WIRE, HA VE
THE CONNECTION AT THE WATER HEATER MADE BY A LOCAL
ELECTRICAL CONTRACTOR AND/OR THE LOCAL ELECTRIC UTILITY .

FIELD INSTALLED WIRING

1. Provide a way to easily shut off the electric power when working
on the water heater. This could be with a circuit breaker or fuse
block in the entrance box or a separate disconnect switch.

2. Install and connect a circuit directly from the main fuse or circuit
breaker box. This circuit must be per applicable codes and have its
own fuse or circuit breaker.

3. Standard 1/2" conduit openings have been made in the water heater
junction box for side or bottom conduit connection.

FILLING THE WATER HEATER

CAUTION

NEVER USE THIS W ATER HEA TER UNLESS IT IS COMPLETEL Y FILLED
WITH WA TER. T O PREVENT DAMAGE TO THE T ANK, THE T ANK MUST
BE FILLED WITH WA TER. W A TER MUST FLOW FROM THE HOT W A TER
FAUCET BEFORE TURNING "ON" GAS TO THE W A TER HEA TER.

To fill the water heater with water:

1. Close the water heater drain valve by turning the handle to the right
(clockwise). The drain valve is on the lower front of the water heater.

2. Open the cold water supply valve to water heater. NOTE: The cold water

supply valve must be left open when the water heater is in use.

3. To insure complete filling of the tank, allow air to exit by opening the
nearest hot water faucet. Allow water to run until a constant flow is
obtained. This will let air out of the water heater and the piping.

4. Check all new water piping for leaks. Repair as needed.

WIRING

You must provide all wiring of the proper size outside of the water
heater. You must obey local codes and electric company requirements
when you install this water heater.

4. Use wire nuts and connect the power supply wiring to the wires inside the
water heater’s junction box. MINIMUM LINE VOLTAGE WIRE NO. 14 AWG.

5. The water heater must be electrically "grounded" by the installer.
The unit will not operate unless it is properly grounded. A green
ground screw has been provided on the water heater's junction box.
Connect ground wire to this location. For complete grounding details and
all allowable exceptions, refer to local codes or in the absence of local
codes, with the National Electrical Code, ANSI/NFPA 70 (current edition).

6. Close the wiring junction box cover.

13

WIRING DIAGRAM FOR ROBERTSHAW CONTROL

SYSTEM - NATURAL GAS ONLY

NOTE: If any of the original wire as supplied with the water heater
must be replaced, it must be replaced with 105°C thermoplastic

AWM wire or its equivalent.

CAUTION

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

MINIMUM LINE VOLTAGE WIRE NO. 14 AWG

14

VENTING

WARNING

TO INSURE PROPER VENTING OF THIS GAS-FIRED W A TER
HEA TER, THE CORRECT VENT PIPE DIAMETER MUST BE
UTILIZED. ANY ADDITIONS OF OTHER GAS APPLIANCES ON
VENT WITH THIS WA TER HEATER ARE PROHIBITED AS THEY
WILL ADVERSELY AFFECT THE OPERA TION OF THE W A TER
HEATER.

WARNING

OBSTRUCTED OR DETERIORATED VENT SYSTEMS MAY
PRESENT SERIOUS HEAL TH RISK OR ASPHYXIA TION.

WARNING

THE VENT PIPE FROM THE WATER HEATER MUST BE 4"
DIAMETER (16" OR 41 CM MIN. AND UP TO 45' OR 13.7 M
WITH ONE 90° ELBOW) OR 6" DIAMETER (45' OR 13.7 M
MIN. AND UP TO 110' OR 33.5 M WITH ONE 90° ELBOW)
AND MUST SLOPE UPWARD 1/8" (3 MM) PER FIVE LINEAR
FEET (1.5 M) FOR ANY HORIZONTAL RUN.

All vent gases must be completely vented to the outdoors of the
structure (dwelling).

Horizontal runs must be securely supported at 3 1/2 foot intervals and
vertical runs supported at 5 foot intervals.

VENTING THROUGH AN OUTSIDE WALL

Items supplied in the carton:

1. One 4" inlet PVC Schedule 40 - 45° vent cap with screen.

2. One 4" outlet CPVC Schedule 80 - 45° vent cap with screen.

3. Two 6" to 4" galvanized steel reducers.

4. Two wire screens to fit one each 6" PVC or CPVC 45° vent caps
(the 6" PVC or CPVC vent caps must be supplied locally).

5. One 4" long CPVC Schedule 40-6" diameter pipe section.

6. Four 4" and 6" wall collars.

All other PVC Schedule 40 or CPVC Schedule 40 or 80 piping and
fittings must be obtained locally.

TYPICAL INST ALLATION - UP TO 45' (13.7 M)

WARNING

FAILURE TO HAVE REQUIRED CLEARANCES BETWEEN
WATER HEATER AND COMBUSTIBLE MATERIAL WILL
RESULT IN A FIRE HAZARD.

WARNING

BE SURE VENT PIPE IS PROPERL Y CONNECTED TO PREVENT
ESCAPE OF DANGEROUS FLUE GASES WHICH COULD
CAUSE DEADL Y ASPHYXIATION.

WARNING

CHEMICAL VAPOR CORROSION OF THE FLUE AND VENT
SYSTEM MA Y OCCUR IF AIR FOR COMBUSTION CONT AINS
CERTAIN CHEMICAL V APORS SPRAY CAN PROPELLANTS,
CLEANING SOLVENTS, REFRIGERATOR AND AIR
CONDITIONER REFRIGERANTS, SWIMMING POOL
CHEMICALS, CALCIUM AND SODIUM CHLORIDE, W AXES,
BLEACH AND PROCESS CHEMICALS ARE TYPICAL
COMPOUNDS WHICH ARE POTENTIALLY CORROSIVE.

Follow illustration above if making an immediate horizontal run of vent
off the blower fittings on top of the water heater.

For vent installations up to 110' (33.5 m), see page 16.

1. The water heater requires its own (separate) venting system.

2. Only 4" CPVC Schedule 40 piping and fittings are acceptable materials
for the first ten feet of the outlet vent system.

3. 4" PVC Schedule 40 or CPVC Schedule 40 or 80 piping and fittings are
acceptable materials for the inlet vent system and for the outlet vent
system after the first 10' (3 m). See vent length chart on page 16.

15

VENTING (CONT'D)

TYPICAL INSTALLATION - UP TO 110' (33.5 m)

Follow illustration above if making an immediate horizontal run of vent
off the blower fittings on top of the water heater.

1. The water heater requires its own (separate) venting system.

2. Only 6" CPVC Schedule 40 or 80 piping and fittings are acceptable
materials for the first ten feet of the outlet vent system.

3. 6" PVC Schedule 40 or CPVC Schedule 40 or 80 piping and fittings are
acceptable materials for the inlet vent system and for the outlet vent
system after the first ten feet. See vent length chart on this page.

VENTING SYSTEM EXAMPLE INSTALLATIONS FOR

ALL MODELS

The vent piping cannot under any circumstances be run downhill.

THE VENT PIPING CAN BE INSTALLED AS FOLLOWS:

1. Horizontal runs require a minimum 1/8" (3 mm) rise per five feet.

2. The total vertical and horizontal run cannot exceed the maximum
length with number of 90° elbows as specified in the tables below.
If more elbows are required, the venting distance must be reduced
5' (1.5 m) for every 90° elbow:

MODEL MODEL NUMBER

100-400 100-400

4" DIA. VENT 6" DIA. VENT

MAX. LENGTH MAX. LENGTH

45' (13.7 m) 110' (33.5 m) 1

40' (12 m) 105' (32 m) 2
35' (11 m) 100' (30.5 m) 3

30' (9 m) 95' (29 m) 4

25' (7.6 m) 90' (27.4 m) 5

20' (6 m) 85' (26 m) 6

15' (4.6 m) 80' (24.4 m) 7

10' (3 m) 75' (23 m) 8

OF

90° DEG .

ELBOWS*

*NOTE: Two 45° elbows are equivalent to one 90° elbow. One 90°
elbow equals 5' (1.5 m) equivalent vent length.

16

3. Minimum vent length is 18" (46 cm) when 4" pipe is used and 45'
(13.7 m) when 6" pipe is used.

CEMENTING PVC OR CPVC PIPE AND FITTINGS

6. QUICKLY assemble parts while cement is fluid! If you wait too long,
recoat pipes.

7. Push pipe completely into socket of fitting, turning as it goes until it
bottoms.

8. Hold pipe and fitting together for 30 seconds. Then carefully clean off
excess with a cloth. Allow connections a sufficient time to cure before
disturbing.

9. Remember that vent pipes must be adequately and securely
supported.

APPROXIMATE SETTING TIME FOR 2 1/2" TO 6" PIPE JOINTS

MOVEMENT COMPLETE

OF JOINT SET

90°F to 150°F 3/4 hr. 8 hrs.

50°F to 90°F 1 hr. 15 hrs.

0°F to 50°F 1 1/3 hr. 18 hrs.

VENT PIPE SEPARA TION

The inlet and outlet vent pipes must be separated by a minimum distance of
10 1/2" (27 cm) with 4" vent, 12" (30.5 cm) with 6" vent and up to 24"
maximum.

Read and observe all safety information printed on primer, cleaner,
and cement containers.

DANGER

PRIMER, CLEANER, AND CEMENTS ARE EXTREMELY FLAMMABLE.
THEY ARE HARMFUL OR F A T AL IF SW ALLOWED. THE V APORS
ARE HARMFUL. THEY MA Y IRRIT ATE EYES AND SKIN AND CAN BE
ABSORBED THROUGH THE SKIN.

CAUTION

ALWAYS STORE PRIMERS, CLEANER, AND CEMENTS IN
COOL, DRY, WELL VENTILATED PLACES. DO NOT STORE
THEM NEAR HEA T , SP ARKS, OR FLAMES. KEEP CONT AINERS
CLOSED. USE THEM IN WELL VENTILA TED AREAS. WEAR
IMPERVIOUS CLOTHING WHILE HANDLING. DO NOT SMOKE,
EAT, OR DRINK WHILE HANDLING. WASH THOROUGHLY
AFTER HANDLING AND BEFORE EATING. WEAR EYE
PROTECTION WHEN HANDLING. IF SWALLOWED, DRINK
WATER, DO NOT INDUCE VOMITING, AND CALL A PHYSICIAN
OR POISON CONTROL CENTER IMMEDIA TELY. IF INHALED,
GET FRESH AIR AND SEEK MEDICAL ATTENTION IF ILL
FEELINGS PERSIST . IN CASE OF EYE AND SKIN CONTACT,
IMMEDIATELY FLUSH WITH PLENTY OF WATER FOR 15
MINUTES AND SEEK MEDICAL ATTENTION IF IRRIT ATION
PERSISTS. KEEP OUT OF REACH OF CHILDREN.

NOTE: Inlet and outlet vent pipes from multiple power direct vent
water heaters must be separated from adjacent heater vent pipes
by a minimum of 10 1/2" (27 cm) with 4" vent or 12" (30.5 cm) with
6" vent.

CUTTING OPENING THROUGH AN OUTSIDE W ALL AND COLLAR
INSTALLATION

After reading the manual and you have determined the location of the
opening in the wall, (using the drawing below), cut one 4 1/2" (11 cm)
diameter (for 4" vent pipe) or 6 1/2" (16.5 cm) diameter (for 6" vent pipe)
hole for the inlet vent piping and one 6 1/2" (16.5 cm) diameter (for 4" vent
pipe) or 8 1/2" (21.6 cm) diameter (for 6" vent pipe) hole for the outlet vent
piping through an exterior wall.

NOTE: When determining location of the openings in the outside
wall allow for the 1/8" (3 mm) rise per 5' (1.5 m) that has taken
place in the horizontal run.

All primers, cleaners, and cements must meet all local codes and applicable
standards of the American Society For Testing Materials Standards.

Before using primers, cleaners, and cements, stir or shake, making sure
contents are liquid. Do not use if found to be lumpy or jellylike.

1. Cut pipe ends squarely removing all burrs and dirt.

2. Dry fit pipe and fittings to be connected for proper fit.

3. Clean pipe and fitting with a primer/cleaner.

4. Apply a thin coat of cement to fitting, avoiding puddling inside.

5. Apply a liberal coat of cement to pipe leaving no voids.

17

The 4" or 6" PVC Schedule 40 or CPVC Schedule 40 or 80 vent pipes can
be run from the water heater through the wall or from the wall to the
water heater, whichever is most convenient. The vent pipes must extend
a minimum of 1 1/2" (3.8 cm) through the exterior wall. Extending the vent
caps as far as possible from the surface of the exterior wall will help
minimize discoloration of the wall. Note that the inside flue mounting
adaptors must be slipped over the vent piping before locating the pipe
through the wall. Before securing the inside and outside collars to the
wall, use a silicone sealer between pipe and opening to insure a water
and air tight seal.

INSTA LLATION SHOWING USE OF PVC OR CPVC PIPE FOR INLET
VENT PIPING:

Inlet piping through any type wall.

CONNECTING VENT TO BLOWER - 4" VENT PIPING

1. If making an immediate horizontal run of vent off the blower, the 6"
(15 cm) to 4" galvanized steel reducer and a PVC Schedule 40
street elbow are required for the inlet pipe, and the 6" to 4" reducer
and two CPVC Schedule 40 or 80 street elbows are required for
the outlet vent. Place the elbows in the required direction on the
reducers, and using 3 sheet metal screws each, attach the reducers
to the blower inlet and outlet collars and then attach the elbows to
the reducers.

INSTALLATION SHOWING USE OF PVC OR CPVC PIPE FOR
OUTLET VENT PIPING:

Outlet vent piping showing 1" (2.5 cm) clearance through a wall of

combustible construction.

2. If there is to be a vertical run of vent from the blower, the 6" to 4"
galvanized steel reducer must be attached to the venting hood collar
and then the PVC inlet pipe can be attached to the reducer using 3
sheet metal screws for each connection. A 6" to 4" reducer must be
attached to the blower outlet collar. Next, an outlet CPVC Schedule 40
or 80 street elbow is attached to the reducer using 3 sheet metal
screws for each connection. The CPVC Schedule 40 or 80 outlet
piping (for the first 10' or 3.05 cm) is then cemented to the street
elbow.

18

CONNECTING VENT TO BLOWER - 6" VENT PIPING

VENTING THROUGH A ROOF

1. If making an immediate horizontal run of vent off the blower, a 7 1/
4" (18.4cm) min. long PVC Schedule 40 pipe section and an elbow
are required for the inlet pipe. A 4" min. long CPVC Schedule 40 pipe
section (supplied), one CPVC Schedule 40 or 80 regular elbow and
one CPVC Schedule 40 or 80 street elbow are required for the
outlet vent.

Items supplied in the carton:

1. One 4" inlet PVC Schedule 40 - 45° vent cap with screen.

2. One 4" outlet CPVC Schedule 80 - 45° vent cap with screen.

3. Two 6" to 4" galvanized steel reducers.

4. Two wire screens to fit one each 6" PVC or CPVC 45° vent caps (the 6"
PVC or CPVC vent caps must be supplied locally).

5. One 4" long CPVC Schedule 40 6" diameter pipe section.

6. Four 4" and four 6" wall collars.

All other PVC Schedule 40 or CPVC Schedule 40 or 80 piping and fittings
must be supplied locally.

2. If there is to be a vertical run of vent from the blower, the PVC Schedule
40 inlet pipe must be attached to the venting hood collar. A 4" min. long
CPVC Schedule 40 pipe section (supplied) must be attached to the
blower outlet collar using three sheet metal screws. A CPVC Schedule
40 or 80 elbow is then cemented on to the end of the 4" pipe section.
CPVC Schedule 40 or 80 pipe (for the first ten feet) is then cemented to
the upturned elbow.

1. The water heater requires its own (separate) venting system.

2. Only 4" or 6" CPVC Schedule 40 or 80 piping and fittings are acceptable
materials for the first ten feet of the outlet vent system.

19

3. 4" or 6" PVC Schedule 40 or CPVC Schedule 40 or 80 piping and
fittings are acceptable materials for the inlet vent system and for
the outlet vent system after the first ten feet. See vent length chart
below.

4. It cannot be connected to existing vent piping or chimney .

5. It must terminate vertically to the outdoors.

6. The total vertical and horizontal run cannot exceed the

maximum length with number of 90° elbows as specified in
the table below. If more elbows are required, the venting
distance must be reduced 5' (1.5 m) for every 90° elbow:

MODEL MODEL

100-400 100-400

4" DIA. VENT 6" DIA. VENT

MAX. LENGTH MAX. LENGTH

45' (13.7 m) 1 10' (33.5 m) 1

40' (12 m) 105' (32 m) 2
35' (11 m) 100' (30.5 m) 3

30' (9 m) 95' (29 m) 4

25' (7.6 m) 90' (27.4 m) 5

20' (6 m) 85' (26 m) 6

15' (4.6 m) 80' (24.4 m) 7

10' (3 m) 75' (23 m) 8

*NOTE: Two 45° elbows are equivalent to one 90° elbow. One 90°
elbow equals 5' (1.5 m) equivalent vent length.

NUMBER

OF

90° DEG .

ELBOWS*

gas control valve could result in a fire or explosion from
leaking gas.

WARNING

If the main gas line shutoff serving all gas appliances is used,
also turn “OFF” the gas at each appliance. Leave all gas
appliances shut off until the water heater installation is
complete.

CORRECT GAS PIPE SIZE FOR

WA TER HEA TERS OPERA TING ON NA TURAL GAS

TOT AL INPUT DISTANCE T O METER, IN FEET

BTU/HR 30 60 90 120 150 180 210

300,000 1 1/4 1 1/4 1 1/4 1 1/2 1 1/2 1 1/2 1 1/2
400,000 1 1/4 1 1/2 1 1/2 1 1/2 2 2 2

A gas line of suf ficient size must be run to the water heater. Consult the
current edition of National Fuel Gas Code ANSI Z223.1, also referred to as
NFP A 54 and the gas comp any concerning pipe size.

There must be:
–A readily accessible manual shut off valve in the gas supply line serving

the water heater, and

–A drip leg (sediment trap) ahead of the gas control valve to help prevent

dirt and foreign materials from entering the gas control valve.

–A flexible gas connector or a ground joint union between the shutoff

valve and control valve to permit servicing of the unit.

Be sure to check all the gas piping for leaks before lighting the water
heater. Use a soapy water solution, not a match or open flame. Rinse of f
soapy solution and wipe dry.

7. Minimum vent length is 18 inches when 4" pipe is used and 45

feet when 6" pipe is used.

NOTE: See page 17 for instructions on cementing PVC or CPVC
pipe and fittings.

GAS PIPING

WARNING

Make sure the gas supplied is the same type listed on the
model rating plate. The inlet gas pressure must not exceed

10.5 in. water column (2.6kPa) for natural gas. The minimum

inlet gas pressure listed on the rating plate is for the purpose
of input adjustment.

WARNING

If the gas control valve is subjected to pressures exceeding
1/2 pound per square inch (3.5kPa), the damage to the

When installed at elevations above 2,000' (610 m), input ratings should be
reduced at the rate of 4 percent for each 1,000' (305 m) above sea level.

WARNING

The appliance and its gas connection must be leak tested before
placing the appliance in operation.

WARNING

The appliance and its individual shutoff valve must be
disconnected from the gas supply piping system during any
pressure testing of that system at test pressures in excess of
1/2 pound per square inch (3.5kPa).
The appliance must be isolated from the gas supply piping system
by closing its individual manual shutoff valve during any pressure
testing of the gas supply piping system at test pressures equal to
or less than 1/2 pound per square inch (3.5kPa).

WARNING

Contaminants in the gas lines may cause improper operation
of the gas control valve that may result in fire or explosion.

20

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 drip leg (sometimes called a sediment trap) must
be incorporated in the piping. The drip leg must be readily
accessible. Install in accordance with the “Gas Piping” section.
Refer to the current edition of the National Fuel Gas Code, ANSI
Z223.1, also referred to as NFP A 54.

SEDIMENT TRAP

A sediment trap shall be installed as close to the inlet of the
water heater as practical at the time or water heater
installation. The sediment trap shall be either a tee fitting
with a capped nipple in the bottom outlet or other device
recognized as an effective sediment trap. If a tee fitting is
used, it shall be installed in conformance with one of the
methods of installation shown.

GAS METER SIZE - CITY GASES ONL Y

Be sure that the gas meter has sufficient capacity to supply the
full rated gas input of the water heater as well as the
requirements of all other gas fired equipment supplied by the
meter. If the gas meter is too small, ask the gas company to
install a larger meter having adequate capacity.

GAS PIPING WITH ALL BLACK IRON PIPE TO GAS CONTROL

Connecting the gas piping to the gas control valve of the water
heater can be accomplished by either of the two methods shown.

GAS PIPING WITH FLEXIBLE CONNECTOR

OPERATING INSTRUCTIONS FOR MODEL 100-400 BEFORE
OPERATING THE WATER HEATER

1. Review the installation and instruction manual before turning on the
electric power and gas supply to the water heater, to safeguard
against a possible dangerous malfunction of the water heater.

2. The electrical supply to this water heater must NOT be turned on
before the tank is completely full of water, the gas supply is available,
and the venting system is completely installed.

3. Because there is normally a certain amount of air in a gas line when a new
water heater has been installed, it may be necessary to re-sequence the
water heater several times before it lights on the initial start-up.

4. Turn on electrical and gas supply to the water heater. Turn the toggle switch
on. Turn the gas cock knob completely on. Go to “Operational Sequence” and
follow the operation of the water heater to insure it is operating properly.

WARNING

AN ODORANT IS ADDED TO THE GAS USED

BY THIS WA TER HEA TER.

FOR YOUR SAFETY
IF YOU SMELL GAS:

1. Do not try to light any appliance.

2. Do not touch any electrical switch; do not use any phone in

your building.

3. Immediately call your gas supplier from a neighbor’s phone.

Follow the gas supplier’s instructions.

4. If you cannot reach your gas supplier, call the fire dep artment.

These models are equipped with an electrically operated venting system
and an intermittent ignition system. For the pilot to light and the burner to
come on, the water heater’s thermostat must call for heat. Then the
system will begin sequencing, each section proving itself before actual
pilot ignition takes place.

21

Before the water heater will operate:

1. The control system must be connected to a 110/120 power supply. This
control system has an overall rating of 12 amps or less. The water heater
must be securely and adequately grounded in accordance with the local
codes or, in the absence of local codes, with the current edition of the
National Electrical Code, ANSI/NFPA 70. The water heater must be
electrically “grounded” by the installer. The unit will not operate unless it is
properly grounded. This should be accomplished by using a grounded
conductor from the service panel to the ground lug located in the junction
box of the water heater

2. The ON/OFF toggle switch, located on the junction box must be in the “ON”
position for the electrical control system of the water heater to operate.

3. The gas knob, located on the gas control valve must be turned to the
“ON” position for gas to be able to flow.

4. The manual shut-off valve between the gas control valve and the burner
assembly must be in the “ON” position.

5. The manual hi-limits must be in the closed position, see “Venting Manual
Reset Switch” in the “For Your Information” section and “Compensating
Thermostat with Manual E.C.O.” in the “Temperature Regulation” section.

The ignition module will then complete a circuit simultaneously to
the spark ignitor, and to the gas pilot valve solenoid. The spark
ignitor will begin sparking and the gas pilot solenoid will open,
allowing gas to pass to the pilot. When a pilot flame has been
established, the flame sensor in the pilot burner assembly will
signal the ignition module, shutting off the spark ignitor. The ignition
module will now complete a circuit to the gas control valve solenoid,
which will open, and allow gas to pass to the burner. Once the
thermostat has been satisfied, the electrical circuits will open and
the burners and blower will shut off.

SAFETY SEQUENCE­NATURAL GAS MODELS ONLY

During a period when the thermostat is calling for heat and there was an
interruption of the pilot flame, the gas valve solenoid will close instantly shutting
off the supply of gas to the burner. The pilot valve solenoid will remain open
allowing gas to flow to the pilot. The ignition module will complete a circuit to the
spark ignitor, which will begin sparking, and the blower stays on.

1. If the pilot flame is reestablished the gas valve solenoid will open allowing
gas to the burner, and the water heater will resume operation.

2. If the pilot flame is not reestablished the gas valve solenoid will remain
closed. The blower will continue to run. The pilot valve solenoid will
remain open allowing gas to pass to the pilot. The spark ignitor will
continue sparking until the pilot flame is reestablished, or the water
heater is re-sequenced by turning the ON/OFF toggle switch “OFF”
and then “ON”.

ROBERTSHA W CONTROL SYSTEM - NATURAL GAS

OPERATIONAL SEQUENCE­NATURAL GAS MODELS ONLY

When the thermostat calls for heat, a circuit is completed to the blower. When the
blower has achieved sufficient venting, the air pressure switch will close. A 24
volt circuit will be completed through the venting manual reset switch and on to
the ignition module.

22

FOR FOR

FOR

FOR FOR

YY

OUR SAFETY READ BEFORE OPERAOUR SAFETY READ BEFORE OPERA

Y

OUR SAFETY READ BEFORE OPERA

YY

OUR SAFETY READ BEFORE OPERAOUR SAFETY READ BEFORE OPERA

WARNING

If you do not follow these instructions exactly, a fire or explosion may
result causing property damage, personal injury or loss of life.

TINGTING

TING

TINGTING

A. This appliance is equipped with an ignition device which automatically

lights the pilot. Do not try to light the pilot by hand.

B. BEFORE OPERATING smell all around the appliance area for gas. Be

sure to smell next to the floor because some gas is heavier than air
and will settle on the floor.
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.

OPERAOPERA

OPERA

OPERAOPERA

1. STOP! Read the safety information above on this label.

2. Turn off all electrical power to the water heater.

3. Remove thermostat access cover.

4. Set the thermostat to lowest setting.

5. This appliance is equipped with an ignition device which
automatically lights the pilot. Do not try to light the pilot by

hand.

6. Turn knob on gas control clockwise to “OFF” position.

TING INSTRTING INSTR

TING INSTR

TING INSTRTING INSTR

• If you cannot reach your gas supplier, call the fire

..department.

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

Never use tools. If the knob will not push in or turn by hand, don’t
try to repair it, call a qualified service technician. Force or
attempted repair may result in a fire or explosion.

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

Immediately contact a qualified service technician or contractor

to replace a flooded water heater. Do not attempt to repair the
unit! It must be replaced!

UCTIONSUCTIONS

UCTIONS

UCTIONSUCTIONS

7. Wait five (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 do not smell gas, go to the next step.

8. At arms length away, turn gas control knob counter-

clockwise to the full “ON” position. WARNING

Do not use gas control knob to regulate gas flow.

9. At arms length away, set the thermostat to desired setting.
The 120°F (67° C) setting which approximates 120°F (67° C) is
preferred starting point. If hotter water is desired, see
instruction manual and “warning” below.

10.Replace thermostat access cover.

11. Turn on all electric power to the appliance.

12. If the appliance will not operate, follow the instructions “To
Turn Off Gas To Appliance” and call your service technician
or gas supplier.

WARNING

Hotter water increases the risk of scald injury. Before changing temperature setting see instruction manual. For
operation at outlet water temperature not in excess of 180°F (82° C).

TT

O O

T

TT

1. Turn off all electric power to the appliance if service is to be
performed.

2. Remove thermostat access cover.

3. Set the thermostat to lowest setting.

TURN OFF GAS TURN OFF GAS

O

TURN OFF GAS

O O

TURN OFF GAS TURN OFF GAS

TT

O O

T

TT

4. Turn gas control knob clockwise to “OFF” position.

DO NOT FORCE.

5. Replace thermostat access cover.

23

APPLIANCEAPPLIANCE

O

APPLIANCE

O O

APPLIANCEAPPLIANCE

TEMPERATURE REGULA TION

DANGER

HOT WA TER CAN SCALD: W ATER HEATERS ARE INTENDED TO
PRODUCE HOT WA TER. W A TER HEA TED TO A TEMPERA TURE
THAT WILL SATISFY SP ACE HEA TING , CLOTHES W ASHING , DISH
WASHING, AND OTHER SANITIZING NEEDS CAN SCALD AND
PERMANENTL Y INJURE YOU UPON CONT ACT . SOME PEOPLE ARE
MORE LIKELY TO BE PERMANENTL Y INJURED BY HOT W A TER
THAN OTHERS. THESE INCLUDE THE ELDERL Y , CHILDREN, THE
INFIRM, OR PHYSICALL Y/MENTALL Y HANDICAPPED. IF ANYONE
USING HOT WATER IN YOUR HOME FITS INTO ONE OF THESE
GROUPS OR IF THERE IS A LOCAL CODE OR STATE LAW
REQUIRING A SPECIFIC HOT W A TER TEMPERA TURE A T THE TAP,
THEN YOU MUST T AKE SPECIAL PRECAUTIONS. NEVER ALLOW
SMALL CHILDREN TO USE A HOT WA TER T AP , OR TO DRAW THEIR
OWN BATH W A TER. NEVER LEA VE A CHILD OR HANDICAPPED
PERSON UNA TTENDED IN A BA THTUB OR SHOWER.

To adjust thermostat setting, remove outer cover of the thermostat. The
thermostat’s adjustment dial is labeled with a range of settings between
120°F (49° C) to 180°F (82° C).

SHOULD OVERHEATING OCCUR OR THE GAS SUPPLY FAIL TO
SHUT OFF, TURN “OFF” THE MANUAL GAS CONTROL VALVE TO
THE APPLIANCE.

START UP CONDITIONS

CONDENSATION

Whenever the water heater is filled with col d water, a certain amount of
condensation will form while the burner is on. A water heater may
appear to be leaking when in fact the water is condensation. This
usually happens:

a. When a new water heater is filled with cold water for the first time.

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 be set for the lowest temperature that satisfies your hot water
needs. This will also provide the most energy efficient operation of the
water heater.

SETTING THE WA TER HEATER TEMPERA TURE A T 120°F (49° C) WILL REDUCE
THE RISK OF SCALDS. Some states require settings at specific lower
temperatures.

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 (13°C). If you experience this type of use you should consider using
lower temperature settings to reduce scald hazards.

Valves for reducing the 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.”

Temperature Time to Produce 2nd & 3rd

Settings Degree Burns on Adult Skin

180°F (82°C) Nearly Instantaneous

170°F (77°C) Nearly Instantaneous

160°F (71°C) About 1/2 Second

150°F (65°C) About 1 - 1/2 Seconds

140°F (60°C) Less than 5 Seconds

130°F (54°C) About 30 Seconds

120°F (49°C) More than 5 Minutes

b. When gas burns and water vapor is produced in water heaters,

particularly high efficiency models where flue temperatures are
lower.

c. When you use large amounts of hot water in a short time and the refill

water is very cold.

Moisture from the products of combustion condense on the cooler tank
surfaces and form drops of water which may fall onto the burner or other
hot surfaces to produce a “sizzling” or “frying” noise.

Excessive condensation can cause pilot outage due to water running
down the flue tube onto the main burner and putting out the pilot.

Because of the suddenness and amount of water, condensation water
may be diagnosed as a “tank leak”. After the water in the tank warms up
(about 1-2 hours), the condition should disappear.

Do not assume the water heater is leaking until there has been enough time
for the water in the tank to warm up.

An undersized water heater will cause more condensation. The water
heater must be sized properly to meet the demands for hot water
including dishwashers, washing machines and shower heads.

Excessive condensation may be noticed during the winter and early spring
months when incoming water temperatures are at their lowest.

Good venting is essential for a gas fired water heater to operate
properly as well as to carry away products of combustion and water
vapor.

24

SMOKE/ODOR

“AIR” IN HOT WATER FAUCETS

It is not uncommon to experience a small amount of smoke and odor
during the initial start-up. This is due to burning off of oil from metal parts,
and will disappear in a short while.

THERMAL EXPANSION

Water supply systems may, because of such events as high line
pressure, frequent cutoffs, the effects of water hammer among others,
have installed devices such as pressure reducing valves, check valves,
back flow preventers, etc... to control these types of problems. When
these devices are not equipped with an internal by-pass, and no other
measures are taken, the devices cause the water system to be closed.
As water is heated, it expands (thermal expansion) and closed systems
do not allow for the expansion of heated water.

The water within the water heater tank expands as it is heated and
increases the pressure of the water system. If the relieving point of the
water heater’s temperature-pressure relief valve is reached, the valve will
relieve the excess pressure. The temperature-pressure relief valve
is not intended for the constant relief of thermal expansion. This is
an unacceptable condition and must be corrected.

Closed systems require installation of a thermal expansion tank.
Failure to do so voids the limited warranty for this water heater.

STRANGE SOUNDS

Possible noises due to expansion and contraction of some metal parts
during periods of heat-up and cool-down do not represent harmful or
dangerous conditions.

WARNING

HYDROGEN GAS: HYDROGEN GAS CAN BE PRODUCED IN A HOT
WATER SYSTEM THAT HAS NOT BEEN USED FOR A LONG
PERIOD OF TIME (GENERALLY TWO WEEKS OR MORE).
HYDROGEN GAS IS EXTREMELY FLAMMABLE AND EXPLOSIVE.
TO PREVENT THE POSSIBILITY OF INJURY UNDER THESE
CONDITIONS, WE RECOMMEND THE HOT WATER FAUCET BE
OPENED FOR SEVERAL MINUTES AT THE KITCHEN SINK
BEFORE ANY ELECTRICAL APPLIANCES WHICH ARE CONNECTED
TO THE HOT WATER SYSTEM ARE USED (SUCH AS A
DISHWASHER OR WASHING MACHINE). IF HYDROGEN GAS IS
PRESENT, THERE WILL PROBABLY BE AN UNUSUAL SOUND
SIMILAR TO AIR ESCAPING THROUGH THE PIPE AS THE HOT
WATER FAUCET IS OPENED. THERE MUST BE NO SMOKING OR
OPEN FLAME NEAR THE FAUCET AT THE TIME IT IS OPEN.

VENTING MANUAL RESET SWITCH

There is a venting manual reset switch located on top of the venting
hood. If the switch is activated, before resetting the switch, check for
flue blockage in the venting system. To reset, press the red button.

Condensation causes sizzling and popping with the burner area during
heating and cooling periods and should be considered normal. See
“Condensation” in this section.

OPERATIONAL CONDITIONS

SMELLY WATER

In each water heater there is installed at least one anode rod (see
parts section) for corrosion protection of the tank. Certain water
conditions will cause a reaction between this rod and the water. The
most common complaint associated with the anode rod is one of a
“rotten egg smell”. This odor is derived from hydrogen sulfide gas
dissolved in the water. The smell is the result of four factors which
must all be present for the odor to develop:

a. a concentration of sulfate in the supply water.

b. little or no dissolved oxygen in the water.

c. a sulfate reducing bacteria within the water heater. (This

harmless bacteria is non-toxic to humans.)

d. an excess of active hydrogen in the tank. This is caused by the

corrosion protective action of the anode.

Smelly water may be eliminated or reduced in some water heater
models by replacing the anode(s) with one of less active material,
and then chlorinating the water heater tank and all hot water lines.
Contact the local water heater supplier for further information
concerning an Anode Replacement Kit #9000029 and this
Chlorination Treatment.

HIGH TEMPERATURE SHUT OFF SYSTEM

This water heater is equipped with an automatic gas shut off
system. This system works when high water temperatures are
present.

E.C.O.

The E.C.O. will activate if the water temperature exceeds 200°F and will
not reset itself. If it is activated, contact a service agent to determine the

cause.

WARNING

Should overheating occur or the gas supply fail to shut off,
turn “off” the manual gas control valve to the appliance.

NOT ENOUGH OR NO HOT WATER

If smelly water persists after anode replacement and chlorination
treatment, then the water supply must be chlorinated or aerated to
eliminate the bacteria.

DO NOT REMOVE THE ANODE LEAVING THE TANK
UNPROTECTED. BY DOING SO, ALL WARRANTY ON THE WATER
HEATER TANK IS VOIDED.

1. Check the manual gas shut off valve to be sure it is open.

2. Check the pilot flame. It may have gone out. All models have an
opening behind the outer door for viewing the pilot.

3. If the pilot is not lit, follow the “Lighting” instructions in this manual or
located above the gas control valve on the water heater to relight the

25

pilot. If the water was extremely hot and is now cold, the high
limit safety temperature shut off may have put out the burner
and pilot. Refer to “High Temperature Shut Off System” in this
section.

4. The gas control knob must be turned to the “ON” position.

5. The temperature adjustment dial may be set too low. See the
“Temperature Regulation” section.

WARNING

IF AFTER INSPECTION OF THE VENT SYSTEM YOU FOUND
SOOTING OR DETERIORATION, SOMETHING IS WRONG. CALL
THE LOCAL GAS UTILITY TO CORRECT THE PROBLEM AND
CLEAN OR REPLACE THE FLUE AND VENTING BEFORE
RESUMING OPERATION OF THE WATER HEATER.

6. The gas company can check the gas input to see if it is correct. An
underfired water heater will not heat water as quickly.

7. Look for leaking or open hot water faucets. Make sure all are
closed.

8. The cold water inlet temperature may be colder during the
winter months. It will take longer to heat the water and seem like
less hot water.

9. If you cannot find what is wrong, call the local gas utility and/or
plumbing contractor.

WATER IS T OO HOT

1. The temperature adjustment dial may be set too high. See the
“Temperature Regulation” section.

NOTE: A period of time is necessary after an adjustment has
been made for the water temperature to reach the new
temperature setting.

2. If lower temperature settings will not lower the water temperature,
shut off the water heater and call the local gas utility.

VENTING SYSTEM INSPECTION

BURNER INSPECTION

WARNING

FLOOD DAMAGE TO A WATER HEATER MAY NOT BE READILY
VISIBLE OR IMMEDIATELY DETECTIBLE. HOWEVER, OVER A
PERIOD OF TIME A FLOODED WATER HEATER WILL CREATE
DANGEROUS CONDITIONS WHICH CAN CAUSE DEATH, SERIOUS
BODILY INJURY, OR PROPERTY DAMAGE. CONTACT A
QUALIFIED SERVICE TECHNICIAN OR CONTRACTOR TO
REPLACE A FLOODED WATER HEATER. DO NOT ATTEMPT TO
REPAIR THE UNIT! IT MUST BE REPLACED!

At least once a year a visual inspection should be made of the main
burner and pilot burner. The drawing is for your reference.

You should check for sooting which is not normal and will impair proper
combustion.

At least once a year a visual inspection should be made of the venting
system. You should look for:

1. Obstructions which could cause improper venting. The combustion

and ventilation air flow must not be obstructed.

2. Damage or deterioration which could cause improper venting or

leakage of combustion products.

WARNING

BE SURE THE VENT PIPING IS PROPERLY CONNECTED TO
PREVENT ESCAPE OF DANGEROUS FLUE GASSES WHICH
COULD CAUSE DEADLY ASPHYXIATION.

WARNING

OBSTRUCTIONS AND DETERIORATED VENT SYSTEMS MAY
PRESENT SERIOUS HEALTH RISK OR ASPHYXIATION.

WARNING

CHEMICAL VAPOR CORROSION OF THE FLUE AND VENT
SYSTEM MAY OCCUR IF AIR FOR COMBUSTION CONTAINS
CERTAIN CHEMICAL VAPORS. SPRAY CAN PROPELLANTS,
CLEANING SOLVENTS, REFRIGERATOR AND AIR CONDITIONER
REFRIGERANTS, SWIMMING POOL CHEMICALS, CALCIUM
AND SODIUM CHLORIDE, WAXES, BLEACH AND PROCESS
CHEMICALS ARE TYPICAL COMPOUNDS WHICH ARE
POTENTIALLY CORROSIVE.

WARNING

SOOT BUILD-UP INDICATES A PROBLEM THAT REQUIRES
CORRECTION BEFORE FURTHER USE. TURN “OFF” GAS TO
WATER HEATER AND LEAVE “OFF” UNTIL REPAIRS ARE MADE,
BECAUSE FAILURE TO CORRECT THE CAUSE OF THE SOOTING
CAN RESULT IN A FIRE CAUSING DEATH, SERIOUS BODILY
INJURY, OR PROPERTY DAMAGE.

BURNER CLEANING

In the event your burner needs cleaning, use the following
instructions:

If inspection of the burner shows that cleaning is required, turn the gas
control knob clockwise to the “OFF” position.

Loose deposits on or around the burner can be removed by carefully
using the hose of a vacuum cleaner. If the burner needs to be removed

26

for cleaning, call the local gas utility to remove and clean the burner
and correct the problem that required the burner to be cleaned.

HOUSEKEEPING

Vacuum around base of water heater for dust, dirt, and lint on a
regular basis.

WARNING

TO INSURE SUFFICIENT VENTILATION AND COMBUSTION AIR
SUPPLY, PROPER CLEARANCES FROM THE WATER HEATER MUST
BE MAINTAINED. SEE “LOCATING THE NEW WATER HEATER”
SECTION. COMBUSTIBLE MATERIALS SUCH AS CLOTHING,
CLEANING MATERIALS, OR FLAMMABLE LIQUIDS, ETC. MUST
NOT BE PLACED AGAINST OR ADJACENT TO THE WATER HEATER
WHICH CAN CAUSE A FIRE.

TEMPERATURE-PRESSURE RELIEF VALVE OPERATION

WARNING

IF THE TEMPERATURE-PRESSURE RELIEF VALVE ON THE APPLIANCE
WEEPS OR DISCHARGES PERIODICALLY, THIS MAY BE DUE TO
THERMAL EXPANSION. YOUR WATER HEATER MAY HAVE A CHECK
VALVE INSTALLED IN THE WATER LINE OR A WATER METER WITH A
CHECK VALVE. CONSULT THE WATER SUPPLIER AND/OR PLUMBING
CONTRACTOR FOR FURTHER INFORMATION. DO NOT PLUG THE
TEMPERATURE-PRESSURE RELIEF VALVE.

DRAINING

THE WATER HEATER SHOULD BE DRAINED IF BEING SHUT DOWN
DURING FREEZING TEMPERATURES. ALSO PERIODIC DRAINING AND
CLEANING OF SEDIMENT FROM THE TANK MAY BE NECESSARY.

1. TURN THE GAS CONTROL KNOB TO THE “OFF” POSITION.

2. CLOSE THE COLD WATER INLET VALVE TO THE WATER HEATER.

The temperature-pressure relief valve must be manually operated at
least once a year.

WARNING

WHEN CHECKING THE TEMPERATURE-PRESSURE RELIEF VALVE
OPERATION, MAKE SURE THAT (1) NO ONE IS IN FRONT OF OR
AROUND THE OUTLET OF THE TEMPERATURE-PRESSURE RELIEF
VALVE DISCHARGE LINE, AND (2) THAT THE WATER MANUALLY
DISCHARGED WILL NOT CAUSE ANY PROPERTY DAMAGE
BECAUSE THE WATER MAY BE EXTREMELY HOT. IF AFTER
MANUALLY OPERATING THE VALVE, IT FAILS TO COMPLETELY
RESET AND CONTINUES TO RELEASE WATER, IMMEDIATELY
CLOSE THE COLD WATER INLET TO THE WATER HEATER,
FOLLOW THE DRAINING INSTRUCTIONS, AND REPLACE THE
TEMPERATURE-PRESSURE RELIEF VALVE WITH A NEW ONE.

3. OPEN A NEARBY HOT WATER FAUCET AND LEAVE OPEN TO
ALLOW FOR DRAINING.

4. CONNECT A HOSE TO THE DRAIN VALVE AND TERMINATE TO AN
ADEQUATE DRAIN.

5. OPEN THE WATER HEATER DRAIN VALVE TO ALLOW FOR TANK
DRAINING.

NOTE: IF THE WATER HEATER IS GOING TO BE SHUT DOWN AND
DRAINED FOR AN EXTENDED PERIOD, THE DRAIN VALVE
SHOULD BE LEFT OPEN WITH HOSE CONNECTED ALLOWING
WATER TO TERMINATE TO AN ADEQUATE DRAIN.

6. CLOSE THE DRAIN VALVE.

7. FOLLOW INSTRUCTIONS IN THE “FILLING THE WATER HEATER” SECTION.

8. FOLLOW THE LIGHTING INSTRUCTIONS IN THE “LIGHTING” SECTION
TO RESTART THE WATER HEATER.

SERVICE

If a condition persists or you are uncertain about the operation of the
water heater, let a qualified person check it out. Call the local utility
and/or plumbing contractor.

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INSTALLATION DIAGRAMS

ONE TEMPERA TURE - ONE HEA TER VERTICAL STORAGE T ANK FORCED CIRCULA TION

WITH OR WITHOUT BUILDING RECIRCULA TION

CAUTION: IF BUILDING COLD

WATER SUPPLY HAS A BACK­FLOW PREVENTER, CHECK
VAL VE OR WA TER METER WITH
CHECK VALVE PROVISIONS
FOR THERMAL EXPANSION OF
WATER IN THE HOT WATER
SYSTEM MUST BE PROVIDED

NOTE: CONNECT RETURN
LINE FROM HOT WATER
CIRCULA TING LOOP (IF USED)
TO COLD WATER INLET LINE.

* PIPE TO OPEN DRAIN

INSTALL IN ACCORDANCE WITH
LOCAL CODES

ONE TEMPERA TURE - ONE HEA TER HORIZONT AL STORAGE T ANK

FORCED CIRCULATION WITH OR WITHOUT BUILDING RECIRCULA TION

DANGER

TEMPERATURE SETTING SHOULD NOT EXCEED
SAFE TEMPERATURE AT FIXTURES. SEE WATER
TEMPERATURE CONTROL WARNING ON PAGE 24.
IF HIGHER PREHEAT TEMPERATURES ARE
NECESSARY TO OBTAIN ADEQUATE BOOSTER
OUTPUT, ADD AN ANTI-SCALD VALVE FOR HOT
WA TER SUPPLIED T O FIXTURES.

*PIPE TO OPEN DRAIN

INSTALL IN ACCORDANCE
WITH LOCAL CODES

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TWO TEMPERA TURE - ONE HEATER HIGH TEMPERA TURE

WITH OR WITHOUT BUILDING RECIRCULA TION

DANGER

TEMPERATURE SETTING SHOULD NOT EXCEED SAFE
TEMPERATURE AT FIXTURES. SEE WATER
TEMPERATURE CONTROL WARNING ON PAGE 24. IF
HIGHER PREHEAT TEMPERATURES ARE NECESSARY
TO OBTAIN ADEQUATE BOOSTER OUTPUT, ADD AN
ANTI-SCALD VALVE FOR HOT WATER SUPPLIED TO
FIXTURES.

CAUTION: IF BUILDING COLD WATER SUPPLY HAS A
BACK-FLOW PREVENTER, CHECK VALVE OR WATER
METER WITH CHECK VAL VE PROVISIONS FOR THERMAL
EXPANSION OF WATER IN THE HOT WATER SYSTEM
MUST BE PROVIDED.

PIPE RELIEF VALVE TO OPEN DRAIN.

*

NOTE: IF TEMPERED WATER IS
RECIRCULA TED, RETURN LINE SHOULD BE
CONNECTED AT POINT “A”.

INSTALL IN ACCORDANCE WITH LOCAL
CODES.

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TWO TEMPERATURE - TWO HEA TERS HIGH TEMPERA TURE

WITH OR WITHOUT BUILDING RECIRCULA TION

TWO TEMPERA TURE - THREE HEATERS (TWO PRE-HEATERS/ONE BOOSTER HEATER)

WITH OR WITHOUT BUILDING RECIRCULATION

MUST BE IDENTICAL HEA TERS

FOR MULTIPLE HEATER INSTALLATION SEE MANIFOLD KIT
SPECIFICATIONS, P AGE 33.

CAUTION: IF BUILDING COLD WATER SUPPLY HAS A BACK-FLOW
PREVENTER, CHECK VALVE OR WATER METER WITH CHECK VALVE
PROVISIONS FOR THERMAL EXP ANSION OF W A TER IN THE HOT WA TER
SYSTEM MUST BE PROVIDED.

DANGER

TEMPERA TURE SETTING SHOULD NOT EXCEED SAFE TEMPERA TURE AT
FIXTURES. SEE WA TER TEMPERA TURE CONTROL WARNING ON P AGE 24.
IF HIGHER PREHEAT TEMPERATURES ARE NECESSARY TO OBTAIN
ADEQUATE BOOSTER OUTPUT, ADD AN ANTI-SCALD VALVE FOR HOT
WA TER SUPPLIED TO FIXTURES.

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TWO TEMPERA TURE - TWO HEATERS (ONE PRE-HEA TER/ONE BOOSTER HEA TER)

WITH OR WITHOUT BUILDING RECIRCULA TION

DANGER

TEMPERA TURE SETTING SHOULD NOT EXCEED SAFE TEMPERA TURE A T
FIXTURES. SEE WA TER TEMPERA TURE CONTROL WARNING ON P AGE 24.
IF HIGHER PREHEAT TEMPERATURES ARE NECESSARY TO OBTAIN
ADEQUATE BOOSTER OUTPUT, ADD AN ANTI-SCALD V AL VE FOR HOT
WA TER SUPPLIED TO FIXTURES

* PIPE RELIEF VAL VE TO OPEN DRAIN
** 140°F (60°C)TO 150°F (66°C) SHOULD BE MAXIMUM WATER

TEMPERATURE MAINT AINED IN THE PRE-HEA TERS.
120°F (49°C) SHOULD BE THE MINIMUM TEMPERA TURE OF WA TER

IN THE PRE- HEATERS.
CONNECT CIRCULA TING LINE FROM FIXTURES, IF USED, TO COLD

WA TER SUPPLY LINE OF PRE-HEA TER.
CONNECT CIRCULA TING LINE OF 180°F (82°C) OR BOOSTED WA TER,

IF USED, TO INLET W ATER LINE TO BOOSTER.
INSTALL IN ACCORDANCE WITH LOCAL CODES.

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TWO TEMPERA TURE - ONE HEATER HIGH TEMPERA TURE

WITH RECIRCULATION OF SANITIZING LOOP

DANGER

TEMPERA TURE SETTING SHOULD NOT EXCEED SAFE TEMPERA TURE AT
FIXTURES. SEE WA TER TEMPERA TURE CONTROL WARNING ON P AGE 24.
IF HIGHER PREHEAT TEMPERATURES ARE NECESSARY TO OBTAIN
ADEQUATE BOOSTER OUTPUT, ADD AN ANTI-SCALD V ALVE FOR HOT
WA TER SUPPLIED TO FIXTURES.

CAUTION: IF BUILDING COLD WATER SUPPLY HAS A BACK-FLOW
PREVENTER, CHECK VALVE OR WATER METER WITH CHECK VALVE
PROVISIONS FOR THERMAL EXP ANSION OF WA TER IN THE HOT WATER
SYSTEM MUST BE PROVIDED.

*PIPE RELIEF VAL VE TO OPEN DRAIN

INSTALL IN ACCORDANCE WITH LOCAL CODES

NOTE 1: TOGGLE SWITCH CONTROLS 180°F (82°C) WA TER CIRCULATION.
INST ALL ON OR CLOSE TO DISHW ASHER. TOGGLE SWITCH MUST BE
CLOSED (ON) DURING THE RINSE OPERA TION AND OPEN (OFF) WHEN
DISHWASHER IS NOT OPERA TING OR WHEN ON LONG ST ANDBY .

NOTE 2: INSTALL LINE TEMPERATURE CONTROL IN AN UNINSULA TED
TEE BEYOND THE DISHWASHER TAKEOFF IN THE SANITIZING LOOP.
CONTROL SHOULD BE SET A T 185°F (85°C).

NOTE 3: ADJUST PLUG COCK SO THE SANITIZING LOOP FLOW RATE
DOES NOT CAUSE UNNECESSARY TURBULENCE IN THE T ANK.

NOTE 4: IF TEMPERED WA TER IS RECIRCULATED, RETURN LINE SHOULD
BE CONNECTED A T POINT A.

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MANIFOLD KITS

Precision cut type “L” all copper A.O. Smith manifold kits assure water flow balance of all units. Without this balance, the full water
heating and storage potential of the system cannot be achieved. Plus, the units with the higher water flow may have a shortened life.
Unions shown in piping diagrams are not included in the manifold kits.

Dimensions shown are for minimum space occupied by the water heaters assemblies.
Space for the venting system and unit servicing must be added.

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SEDIMENT REMOVAL

Waterborne impurities consist of the particles of soil and sand which
settle out and form a layer of sediment on the bottom of the tank.

For convenience, sediment removal and lime scale removal should be
performed at the same time.

LIME SCALE REMOVAL

To dissolve and remove the more stubborn mineral deposits, A.O. Smith
UN-LIME® Professional Delimer should be used.

A.O. Smith UN-LIME® Professional Delimer is an easy to handle
patented food grade acid formulated specifically for lime scale
removal from all types of water using equipment. Available in 1 gallon
(3.8L) (part no. 4763) and 5 gallon (19L) (part no. 4813) sizes.
Hydrochloric base acids are not recommended for use on glass­lined tanks.

The amount of calcium carbonate (lime) released from water is in direct
proportion to water temperature and usage. The higher the water
temperature or water usage, the more lime deposits are dropped out of
the water. This is the lime scale which forms in pipes, heaters and on
cooking utensils.

Lime accumulation not only reduces the life of the equipment but also
reduces efficiency of the heater and increases fuel consumption.

The usage of water softening equipment greatly reduces the hardness
of the water. However, this equipment does not always remove all of the
hardness (lime). For this reason it is recommended that a regular
schedule for deliming be maintained.

The depth of lime buildup should be measured periodically. Heaters will
have about 3" (7.6 cm) of lime buildup when the level of lime has reached
the bottom of the cleanout opening or about 1" (2.5 cm) of lime buildup if
it has reached the drain valve opening. A schedule for deliming should be
set up, based on the amount of time it would take for a 1" (2.5 cm) buildup
of lime.

Example 1:

Initial inspection shows 1/2" (1.3 cm) of lime accumulation.
Therefore, the heater can be delimed once a year.

Example 2:

Initial inspection shows 2" (5 cm) of lime accumulation. Therefore,
the heater can be delimed every 3 months.

Sediment and lime scale removal may be accomplished through the
cleanout opening furnished on the heater, see Figure 25. The heater must
be drained, see DRAINING, before removing cleanout cover on tank.

A.O. Smith Form No. 4800, entitled "Why, When and How", describes
tank cleaning methods and materials. UN-LIME and the booklet may be
obtained through your A.O. Smith dealer or distributor.

The cleanout opening is shown in Figure 25. To clean heater through
cleanout opening, proceed as follows:

1. Turn off water inlet valve, the heater electrical disconnect switch
and open drain valve.

2. Remove outer cover plate from lower side of heater jacket.

3. Remove cover from cleanout opening.

4. Remove lime, scale or sediment using care not to damage the glass­lining.

5. Inspect cleanout plate gasket: If new gasket is required, replace with
A.O. Smith part no. 99038.

6. Install cleanout plate. Be sure to draw plate up tight by tightening
screws securely.

7. Close drain valve, open water inlet line and turn on the power burner
electrical disconnect switch.

8. Check for water leakage.

9. Replace outer jacket cover plate.

ANODE INSPECTION AND REPLACEMENT

This water heater is equipped with multiple sacrificial anodes. Anodes
protect the glass-lined tank from corrosion by sacrificing themselves
through electrolysis. When the anode material is consumed, there is no
more protection and corrosion of the tank accelerates.

Inspection of the anode every 6 to 12 months allows you to identify a
spent anode and replace it. Replace the anode when its diameter is 3/8"
(1 cm) of an inch, or annually which ever is first. Aggressive, very hot
and softened water causes rapid consumption of the anode requiring
frequent inspections. Anodes are available from your distributor or A.O.
Smith.

FIGURE 25

REPLACEMENT PARTS

Replacement parts may be ordered through A.O. Smith dealers,
authorized servicers or distributors. Refer to the Yellow Pages for
where to call or contact A.O. Smith Water Heater Parts Fulfillment, 125
Southeast Parkway, Franklin, TN, 1-800- 527-1953. When ordering parts
be sure to state the quantity, part number as it appears on the product.
Refer to the parts list for more information.

34

Model BPD 400 Limited Warranty

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

1. THE T ANK
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 first 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 efficient 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 efficient 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, certified
by A.G.A./CGA and approved by the American Society of Mechanical Engineers, must have been installed.
a. This warranty shall apply only when the heater is used:

(1 ) at temperatures not exceeding the maximum setting of its thermostat;
(2 ) at water pressure not exceeding the working pressure shown on the water heater;
(3) when operated free from the damaging effects of uncontrolled water hammer;
(4 ) when filled with potable water, free to circulate at all times;
(5 ) in a noncorrosive and non-contaminated atmosphere;
(6) in its original installation location;
(7) with factory approved anode(s) installed;
(8 ) in the United States, its territories or possessions.
(9 ) Fired at the factory rated input;

(10) Owned by the original purchaser;

(11) Sized in accordance with proper sizing techniques for commercial water heaters;

(12) Bearing a rating plate which has not been altered, defaced or removed except as required by the warrantor;

b. Any accident to the water heater, any misuse, abuse (including freezing) or alteration of it, any operation of it in a modified form, any use

of insulation blankets, or any attempt to repair tank leaks will void this warranty.

c. This warranty is void if a device acting as a backflow prevention device (check valves etc.) is installed in the cold water supply the heater

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.

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

returning the claimed defective heater or part to such distributor.

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

5. LIMITATIONS ON IMPLIED WARRANTIES

Implied warranties, including the warranty of merchantability imposed on the sale of this heater under state or provincial law are limited to one
(1) year duration for the heater or any of its parts. Some states and 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:

a. The warrantor will only honor replacement with identical or similar water heater or parts thereof which are manufactured or distributed by

the warrantor.

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

exclusions may not apply to you.

b. This warranty gives you specific 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.

U.S. Customers
A. O. Smith Water Products Company
500 Tennessee Waltz Parkway
Ashland City, TN 37015
Telephone: [phone]

Model No._____________________________Serial No.___________________________________________Date Installed________________
Dealer’s

Name______________________________________________________________________________________________________________

35

A.O. SMITH WATER PRODUCTS CO.

500 Tennessee Waltz Parkway, Ashland City, TN 37015

PHONE: [phone] • FAX: [phone]

www.hotwater.com / email: [e-mail]

36