Bradford White PE4403S Series User manual

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Manual 238-48494-00A
SERVICE
MANUAL
SUPPLEMENT
Troubleshooting Guide
and Instructions for Service
(To be performed ONLY by
qualified service providers)
Models Covered
by This Manual:
PE4403S*F(BN,SX)
PE440T*F(BN,SX)
PE4503*F(BN,SX)
PE2XR504T*F(BN,SX)
(*) Denotes Warranty Years
Gas Water Heaters
Programmable Efficiency
®

Page 2
Table of Contents
Section Page
Introduction ______________________________________________5
How to Use this Manual _____________________________________6
Tools Required for Service ___________________________________6
Specifications _____________________________________________7
Sequence of Operation______________________________________9
Power Up Sequence
Normal Heating Sequence
Abnormal Operation
Troubleshooting __________________________________________ 13
Burner Maintenance _______________________________________ 17
Burner Inspection
Burner Cleaning Procedure
Pilot Maintenance _________________________________________ 19
Pilot Inspection, Testing and Replacement
Thermal Well Testing ______________________________________ 21
Determine Water Temperature Inside Tank_____________________ 22
Component Disassembly ___________________________________ 24
Gas Control Removal ______________________________________ 25
Gas Control Assembly _____________________________________ 26
Flammable Vapor Sensor Testing_____________________________ 27
120 VAC Circuit Trace _____________________________________ 28
Relay Replacement________________________________________ 28
Common Terms __________________________________________ 30
Notes __________________________________________________ 30
Parts List _______________________________________________ 31
2

WARNING
If the information in these instructions is not followed exactly, a fire or explosion may
result causing property damage, personal injury, or death.
What to do if you smell gas:
xDo not try to light any appliance
xDo not touch any electrical switch; do not use any phone in your building
xImmediately call your gas supplier from a neighbor’s phone. Follow the gas supplier’s
instructions.
xIf 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.
FAILURE TO INSTALL AND MAINTAIN A NEW, LISTED 3/4” X 3/4” TEMPERATURE AND
PRESSURE RELIEF VALVE WILL RELEASE THE MANUFACTURER FROM ANY CLAIM THAT
MIGHT RESULT FROM EXCESSIVE TEMPERATURE AND PRESSURES.
CAUTION
Incorrect operation of this water heater may create a hazard to life and property and will
nullify the warranty.
If sweat fittings are to be used, DO NOT apply heat to the nipples on top of the water
heater. Sweat the tubing to the adapter before fitting the adapter to the water
connections. It is imperative that heat is not applied to the nipples containing a plastic
liner.
Turn off or disconnect the electrical power supply to the water heater before servicing.
Label all wires prior to disconnection when servicing controls. Wiring errors can cause
improper and dangerous operation. Verify proper operation after servicing.
DANGER
Do not store or use gasoline or other flammable, combustible, or corrosive vapors and
liquids in the vicinity of this or any other appliance.
NOTICE
Before proceeding, please inspect the water heater and its components for possible
damage. DO NOT install any water heater with damaged components. If damage is
evident, then please contact the supplier where the water heater was purchased or the
manufacturer listed on the rating plate for replacement parts.
Page 3
3

Page 4
WARNING
Water heaters are heat producing appliances. To avoid damage or injury, do not store
materials against the water heater or any of its components. Use proper care to avoid
unnecessary contact, especially by children, with the water heater and its components.
Under no circumstances must flammable materials, such as gasoline or paint thinner be
used or stored in the vicinity of this water heater or in any location in which the fumes
could reach the water heater.
Hydrogen gas can be produced in an operating water heater that has not had water drawn
from the tank for a long period of time (generally two weeks or more). Hydrogen gas is
extremely flammable. To prevent the possibility of injury under these conditions, we
recommend a hot water faucet to be open for several minutes at the kitchen sink before
you use any electrical appliance which is connected to the hot water system. If hydrogen is
present, there will be an unusual sound such as air escaping through the pipes as hot
water begins to flow. Do not smoke or have open flame near the faucet at the time it is
open.
DO NOT ATTEMPT TO LIGHT ANY GAS APPLIANCE IF YOU ARE NOT CERTAIN OF THE
FOLLOWING:
Liquefied petroleum gases/propane gas and natural gas have an odorant added by the gas
supplier that aids in the detection of the gas. Most people recognize this odor as a “sulfur”
or “rotten egg” smell. Other conditions, such as “odorant fade” can cause the odorant to
diminish in intensity, or ”fade,” and not be as readily detectable. If you have a diminished
sense of smell, or are in any way unsure of the presence of gas, immediately contact your
gas supplier from a neighbor's telephone. Gas detectors are available. Contact your gas
supplier, or plumbing professional for more information.
Do not operate the water heater or its accessories without the Accessory Module cover in
place. Do not operate the water heater or Setback Control without the Setback Control
Junction Box Assembly cover in place.
Do not operate the water heater, Accessory Module, and Setback Control with jumpered or
absent controls or safety devices.
Turn off or disconnect the electrical power supply to the water heater and its accessories
before servicing. Label all wires prior to disconnection when servicing controls. Wiring
errors can cause improper and dangerous operation. Verify proper operation after
servicing.
All electrical wiring must be installed and grounded in accordance with local codes, or in
the absence of local codes, the National Electrical Code, ANSI/NFPA 70 and/or CSA C22
Electrical Code.
4

Page 5
The Bradford White DEFENDER Safety System®
The Bradford White DEFENDER Safety System was designed to resist the ignition of
flammable vapors that can occur outside of the water heater. Use and installation are nearly
identical to previous versions of atmospherically fired and vented water heaters. A number of
exclusive design features are incorporated in the system that will require additional knowledge
on the part of the qualified service provider. The following information will instruct service
professionals on the function, proper diagnosis, and repair of water heaters employing the
Bradford White DEFENDER Safety System.
Introduction
The new Bradford White Programmable Efficiency water heaters are designed to provide
reliable performance with enhanced standard features. New design features include reliable
spark-to-pilot ignition system, enhanced diagnostics, simplified servicing, and the Bradford
White Defender Safety System.
Spark-to-Pilot Ignition System - employing the spark-to-pilot ignition system promotes
reliable and consistent pilot and main burner ignitions to provide hot water on demand.
Integrated Immersion Thermal Well/Gas Control with LED -was developed for ease of
troubleshooting by providing simple diagnostic codes to pinpoint an installation or component
performance issue.
Rugged Wiring Connections - receptacle type connections promote error free wiring.
The gas control maintains water temperature, ignition sequence, and regulates gas flow. If a
situation outside of normal operating parameters exists, the gas control diagnostic LED will
flash a code to positively identify an operational issue.
This service manual is designed to facilitate problem diagnosis and enhance service efficiency.
To further promote quicker service times, the gas control can be removed and replaced without
draining the water heater. A special tool is required and will be provided with each gas control
kit shipped from your Bradford White wholesale distributor.
Please read the service manual completely before attempting service on this new series of
models.
How the DEFENDER Safety System Works
During normal operation, air for combustion is drawn into the water heater through the
openings in the jacket. This air travels down and around the combustion chamber and enters
through holes in the very bottom of the corrosion resistant combustion chamber. The air then
travels up through the flame arrestor louvers, where the velocity of the air is increased and its
direction altered. The air then mixes in a normal manner with supplied gas and is efficiently
combusted, producing very low NOxemissions.
In the unlikely event trace amounts of flammable vapors are present in the air flowing into the
combustion chamber, the vapors are harmlessly ignited by the burner. If flammable vapors are
in sufficient quantity to prevent normal combustion, the flammable vapor sensor recognizes
this and shuts down the pilot and main burner. Should the flammable vapors continue to burn,
the flame arrestor prevents the flames from traveling backwards and igniting vapors outside of
the combustion chamber. In addition, the resettable thermal switch will open and shut down
the pilot and main burner.
Introduction
5

Page 6
How to Use this Manual
This manual serves as a supplement to the Defender Atmospheric service manual, p/n
238-44943-00. Please refer to the Defender Atmospheric service manual for all features on
this water heater that are consistent with a Defender (standard) Atmospheric water heater.
It is intended for this manual to be used by qualified service personnel for the primary purpose
of troubleshooting and repair of the Bradford White Programmable Efficiency water heaters.
Understanding the sequence of operation section of this manual will contribute greatly to
troubleshooting the water heater.
The Honeywell WV4460E Electronic Gas Control will display error codes in the event of
abnormal operation. Diagnostic codes are listed in the troubleshooting chart beginning on page
13 of this service manual. The troubleshooting chart will also indicate the probable cause for
the diagnostic code and direct the service professional to a service procedure to properly
diagnose the abnormal operation.
Contact the Bradford White technical support group immediately if diagnosis cannot be made
using the methods described in this service manual.
Tools Required for Service
Manometer: A liquid “U” tube type or a digital (magna-helic) type can be used. This device is
used to measure gas and/or air pressure and vacuum.
Multi-Meter: Adigital type is strongly recommended. This device is used to measure electrical
values. The meter you select must have the capability to measure volts AC, volts DC, amps,
micro-amps and ohms.
Electronic Probes: In some cases, standard multi-meter probes will damage or simply not be
effective to obtain certain voltage and ohm reading. It will be necessary to have special
electronic “pin” type multi-meter probes. These probes are available at most electronic
wholesale outlets.
Thermometer: Used to measure water temperature. An accurate thermometer is
recommended.
Water Pressure Gage: Used to measure water supply pressure. Also used to determine tank
pressure by adapting to the drain valve of the heater.
Gas Control Service Tool: BWC p/n 239-45991-00. A specialized tool designed to remove
the gas control from the thermal well. Available from your Bradford White parts supplier and is
supplied with replacement gas controls.
Various Hand Tools: Pipe wrench, channel locks, open end wrenches (3/8", 7/16", 1/2"), 12"
crescent wrench, Allen wrench set, screw drivers (common & Phillips), 1/4" nut driver, pliers
(common & needle nose), socket set, side cutters, wire cutters, wire strippers, wire crimpers,
torpedo level, small shop vac, step ladder, flashlight, and 5 gallon pail.
How to Use this Manual
6

Page 7
Specifications
Power Supply Dedicated 120VAC, 60 Hz, 15A
Gas Supply Pipe
Minimum 1/2” NPT (Schedule 40 black iron pipe
recommended)
Approved Gas Type Natural or Propane; unit must match gas type supplied
Gas Pressure 5” w.c. minimum for Natural Gas; 11” w.c. for Propane; 14”
w.c. maximum for Natural Gas / Propane
Approved Vent Materials Single or Double Wall Metal Vent Pipe
Minimum Clearance for
Servicing
18” from top; 24” from front; 4” from sides and rear
Water Supply Pressure 150 psi maximum allowable working pressure; check local
codes for supply pressure
ECO Limit 188°F (87°C)
Temperature Setpoint Range 60°F (16°C) to 160°F (71°C); approximate temperatures
Specifications
7

Page 8
Ignition State Timing
Energize Relay and Verify (Closed Circuit) 15 seconds
Trial for Ignition 90 seconds
Flame Stabilization Period 3 seconds
Re-energize Relay and Verify 15 seconds
Flame Failure Response Time 1.5 seconds (2 second maximum; 1 second
minimum)
De-energize Relay and Verify (Open Circuit) 15 seconds
Relay Fault (failed open/close) Retry after 2 minutes
Soft Lockout Retry after 5 minutes
ECO Limit Lockout Indefinite (See page 11 to reset)
Verify Resistive Delay Retry after 2 minutes (repeats 5 times)
Simulated Resistive Load Lockout Indefinite (cycle power to reset)
Hardware Error Lockout Indefinite (self clears if fault clears for at least 15
seconds)
Specifications
Wiring Diagram
Control Timings
HOT
LOW
HOT
VERY
A
C
B
Honeywell
W
PILOT
SETBACK CONTROL
GAS VALVE
R
BL
W
BK
GY
POWER CORD
G
BK W
BK
W
BK
BK
BK
G
G
W
W
BKW
BL
Y
R
MODULE
ACCESSORY
BK
W
R
BK
W
SETBACK CONTROL
JUNCTION BOX
FLAMMABLE
VAPOR SENSOR
WATER
TEMPERATURE
SENSOR
BK
BK BK
TRANSFORMER
AC AC
PLUG-IN
RE-SETTABLE
THERMAL SWITCH
W
R
BK
BK
W
8

Page 9
Note: The Sequence of Operation section is in addition to the Defender Atmospheric
Service Manual, p/n 238-44943-00.
Power Up Sequence
1. Start-up: Upon power up, the gas control runs a safe start check with a typical
delay of 5 seconds.
2. Flammable Vapor Verification: The gas control verifies that the Flammable Vapor
Sensor is in the proper operating range prior to energizing any components. If the
sensor is within the proper range, the gas control resumes normal operation. If the
Flammable Vapor Sensor is out of range, the gas control LED immediately flashes
7times with a 3 second pause.
Normal Heating Sequence
1. Thermostat Calls for Heat: Prior to energizing the relay, the gas control verifies
the safety circuit to see if it is in the correct state. If the safety circuit is closed, the
gas control LED flashes 2 times with a 3 second pause. The gas control waits 2
minutes. Then, the control cuts power to the relay. This cycle repeats until the
safety circuit opens.
2. Relay Energized
3. Safety Circuit Check: If the safety circuit does not close within 30 seconds, the
gas control LED flashes 3 times with a 3 second pause. The relay is powered for a
maximum of 30 seconds every 2 minutes trying to close the safety circuit. This
cycle repeats as long as there is a call for heat.
4. Hold Period (15 seconds)
5. Trial for Pilot Ignition (90 seconds): The gas control lights the pilot by activating
the spark igniter and gas flow to the pilot burner. If flame is not sensed within 90
seconds, the spark igniter and gas flow are deactivated. The relay will remain
powered, and the gas control LED flashes 6 times with a 3 second pause.
6. Main Burner Ignition: After pilot flame is sensed, the gas control activates the
main valve for main burner ignition. The gas control will ignore flame signals for 3
seconds to allow for the main burner to stabilize.
Sequence of Operation
9

Page 10
Normal Heating Sequence (cont’d)
7. Steady State Operation: During steady state operation, the gas control monitors:
Thermostat Temperature Sensor: When the setpoint temperature is satisfied, the
gas control is shutdown, and power is removed from the relay. The gas control
LED flashes a short flash once every 4 seconds (Idle status code).
Relay Status: If the relay is altered during a call for heat, the pilot and main valves
are shutdown. The relay is powered attempting to close the safety circuit. The gas
control LED flashes 3 times with a 3 second pause.
Flame Sensor: If flame is lost, the pilot and main valves are shutdown. The relay is
powered. The gas control attempts to re-light the pilot 4 times. If unsuccessful,
power is removed from the relay, and the gas control proceeds to a 5 minute
lockout. The gas control re-attempts to light the pilot starting at Normal Heating
Sequence #2.
8. Thermostat Satisfies: Gas control LED flashes once every 4 seconds.
9. Burner Off
10.Relay De-energized (15 seconds)
Abnormal Operation
1. Flammable Vapor Sensor Fault:
A) If the resistance is greater than 70,000 ohms: The gas control immediately turns
off all outputs. The gas control waits and monitors resistance for 30 seconds. If the
resistance is greater than 65,000 ohms after 30 seconds, the gas control proceeds
to verify resistive delay for 2 minutes and flashes 7 times then 1 time with a three
second pause. This process is repeated 5 times until the control either returns to
normal operation or proceeds to flammable vapor lockout.
B) If the resistance is below 3000 ohms: The gas control immediately turns off all
outputs and proceeds to flash 8 times then 1 time with a three second pause. The
error self clears if the resistance returns to normal range for at least 15 seconds.
Sequence of Operation
10

Page 11
Abnormal Operation (cont’d)
2. Temperature Sensor Fault:
A) Temperature Sensor Open Circuit: The gas control immediately turns off all
outputs and proceeds to flash 8 times then 3 times with a three second pause. The
error self clears if the fault clears for at least 15 seconds.
B) Thermal well sensors not reading the same temperature within ±5.5°F: The gas
control immediately turns off all outputs and proceeds to flash 8 times then 3 times
with three second pause. The error self clears if the fault clears for at least 15
seconds.
C) Water Temperature in excess of ECO (Energy Cut Off) Limit: The gas control
immediately turns off the pilot and main valves. The gas control LED proceeds to
flash 4 times with a 3 second pause.
To reset the gas control, rotate the setpoint knob to the minimum setting for at least
6seconds before returning to desired temperature setting.
3. Safety Circuit Fault:
A) Safety Circuit Failed to Close: The gas control proceeds to flash 3 times with a 3
second pause. The gas control waits 5 minutes, and then tries to energize the
relay again.
B) Safety Circuit Failed to Open: The gas control proceeds to flash 2 times with a 3
second pause. The gas control waits 5 minutes, and then tries to de-energize
the relay.
4. Trial for Ignition Fault:
A) Relay Fault During Trial: The gas control stops the trial for ignition. The gas
control proceeds to flash 3 times with a 3 second pause. The gas control waits
5minutes, and then tries to energize the relay again.
B) Flame Not Sensed: The gas control energizes the spark igniter attempting to
light the pilot and prove flame. If flame is not sensed within 90 seconds, the
spark igniter turns off, the pilot valve is closed. The gas control LED flashes 6
times then 1 time with 3 second pause. The control waits 5 minutes before
repeating the ignition sequence.
Sequence of Operation
11

Page 12
Abnormal Operation (cont’d)
5. Flame Sensing Fault:
A) Flame Lost During Run: The gas control turns off pilot and main valves. The gas
control increments the recycle count, if the recycle count has not reached its limit
(4), another trial for ignition begins. If the recycle count has been reached, the gas
control LED flashes 6 times then 3 times with a 3 second pause. The gas control
waits 5 minutes before repeating the ignition sequence.
B) Flame Sensed Out of Sequence: The gas control only looks for pilot flame when
the relay is energized. If flame is present when the pilot valve is not open, the gas
control proceeds to wait for flame loss and flashes 5 times with 3 second pause.
This continues until flame is lost. Once the flame signal is lost, the control flashes 6
times then 4 times with a 3 second pause. The control waits 5 minutes before
repeating the ignition sequence.
Sequence of Operation
12

Page 13
Note: The Troubleshooting section replaces pages 4-6 in the Defender Atmospheric
service manual, p/n 238-44943-00.
LED Status Control Status Probable Cause Service Procedure
None (LED
not on or
flashin
g)
Ele ctrica l po w er not
present
Control power switch in "OFF"
position.
Su
pp
l
y
volta
g
e interru
p
ted.
Turn Power On
One short
flash every
four seconds
Stand-by mode,
Thermostat is
satisfied
(
no faults
)
Temperature demand is satisfied
(no call for heat) Normal operation
Alternates
bright and
dim
(
heartbeat
)
Thermostat calling
for heat (no fault)
Tank temperature below
setpoint of thermostat Normal operation
Short flash
once every
second
Weak pilot signal
on last call for heat
1. Unstable pilot
2. Pilot tube blocked or restricted
3. Oxidation build-up on pilot
electrode
4. W ire damage to pilot
assembly or bad connection at
gas control
1. See Burner Inspection on
page 17
2-4. See Pilot Inspection,
Testing and Replacement on
page 19
Two flashes,
three second
pause
Rela y not w o rking Fa ulty re lay
1. Verify cord sets are fully
plugged in
2. See Relay Replacement on
p
a
g
e 28
Three
flashes,
three second
pause
Rela y not w o rking Fa ulty re lay
1. Verify cord sets are fully
plugged in
2. See Relay Replacement on
page 28
Four flashes,
three second
pause
Excessive tank
temperature,
system must be
reset
1. Thermal w ell se nsor out of
calibration
2. Faulty gas control
1. Test Gas Control & Thermal
Well
2. Replace gas control if
necessar
y
Five flashes,
three second
pause
False pilot flame
present Pilot valve stuck in open position Replace gas control
Six flashes,
one flash,
three second
pause (Soft
Lockout)
Failed to light pilot,
system resets after
(5) minutes
1. Unstable pilot
2. Pilot tube block or restricted
3. Oxidation build-up on pilot
electrode
4. W ire damage to pilot
assembly or bad connection at
g
as valve
1. See Burner Inspection on
page 17
2-4. See Pilot Inspection,
Testing and Replacement on
page 19
Observe the green LED on the water heater gas
control. Diagnostic codes are displayed with a 3
second pause before repeating. Once the diagnostic
code is known, check and repair the water heater, as
recommended in the table below.
Troubleshooting
Green LED
13

Page 14
LED Status Control Status Probable Cause Service Procedure
Six flashes,
two flashes,
three second
pause (Soft
Lockout)
Relay not w orking
properly during
burner operation,
system auto resets
after (5) minutes
Faulty relay See Relay Replacement on
page 28
Six flashes,
three
flashes,
three second
pause (Soft
Lockout)
Pilot fla me
extinguished,
system auto resets
after (5) minutes
1. Unstable pilot
2. Pilot tube block or restricted
3. Oxidation build-up on pilot
electrode
4. Wire damage to pilot
assembly or bad connection at
gas control
5. Insufficient combustion air
6. Insufficient
g
as
p
ressure
1. See Burner Inspection
on page 17
2-4. See Pilot Inspection,
Testing and Replacement
on page 19
5. Refer to Installation &
Operation Manual
Six flashes,
four flashes,
three second
pause
Undesired false
pilot flame sensed,
system auto resets
Pilot valve stuck in open position Replace gas control
Seven
flashes,
three second
pause
Flammable vapor
sensor or
resettable thermal
switch fault
detected, see
warning label
1. Flammable vapor present
2. Flammable vapor sensor
exposed to excessive moisture
3. Flammable vapor sensor
exposed to extreme ambient
temperature
4. Resettable thermal switch
o
p
en
See Flammable Vapor
Sensor Testing on page 27
Eight
flashes, one
flash, three
second
pause
Flammable vapor
sensor out of
specification,
possible short
1. Flammable vapor sensor out
of specification; verify Flammable
Vapor Sensor (FVS) resistance is
not below 25 k.
2. Possible short in flammable
vapor sensor or resettable
thermal s w itch w irin
g
See Flammable Vapor
Sensor Testing on page 27
Eight
flashes,
three
flashes,
three second
pause
Thermal well sensor
damaged or
unplugged or gas
control electronics
fault detected
1. Damage to thermal well wires
2. Thermal well sensor
resistance out of range
3. Replace thermal well
4. Verify control is not wet or
physica lly damaged
5. Rese t control on/off s w itch
6. Replace gas control if 8-3 error
persists
See Thermal Well Testing
on page 21
Eight
flashes, four
flashes,
three second
pause
Gas control fault
detected
1. Verify control is not wet or
physica lly damaged
2. Rese t control on/off s w itch
3. Replace gas control if 8-4 error
persists
1. Replace gas control if
wet or physically damaged
2. Cycle power
3. Replace gas control
Troubleshooting
14

Page 15
Troubleshooting
Gas Valve / Control Model
Diagnostic
Code # Description Accessory Module
WV4460E
(intermittent pilot
gas control)
Conn Setback Control not connected to gas valve / control or
improperly wired together. x x
2 Relay remains energized x
4 Weak pilot signal detected. x
6 Pilot signal detected out of sequence. x
18 Internal gas valve fault detected. x
20 Failed to light pilot. x
23 Pilot signal detected out of sequence (before it
should). x
24 Pilot signal detected out of sequence (after it should). x
29 Relay failed to energize x
31 Upper tank sensor out of specification.
32 Lower tank sensor out of specification. x
63 Ignition successful, but flame lost during run cycle.
Soft lockout. x
64 Internal gas valve fault detected. x
85 Soft Lockout due to maximum number of recycles
exceeded, last recycle was from pressure switch open x
87 A manual reset is required due to Rollout Limit x
89 Equipment missing or improperly wired together. x
93 Internal gas valve fault detected. x
95 Flammable vapor sensor fault detected, see warning
label. x
96 Flammable vapor sensor out of specification, possible
short. x
143 Water heater tank leak detected. x
145 Leak sensor improperly installed or leak sensor
resistor missing. x
The table, below, details the diagnostic codes that can be seen on the Setback
Control. Reference the Setback Control manual, p/n 238-47808-00, for more
details on this control.
15

Page 16
Troubleshooting
LED Status Accessory Module
Status Probable Cause
Green LED on continuously. Power on (no fault). n/a
Red One flash and three
second pause.
Leak alarm fault.
Inlet Shut-off valve
open.
Water heater tank leak.
Red Two flashes and three
second pause.
Leak alarm fault.
Inlet Shut-off valve
closed.
Water heater tank leak.
Amber Four flashes and three
second pause.
Leak sensor
malfunction.
1. Leak Sensor resistor
removed.
2. Leak Sensor improperly
connected to Accessory
Module.
Amber Five flashes and three
second pause.
Gas control
missing / not
connected.
1. Wrong gas control wire
harness was used.
2. Accessory Module was
not connected to gas
valve.
Red LED strobe (quick
flashes). Hardware error. Internal electronics failure, replace Accessory Module.
The table, below, details the diagnostic codes that can be seen on the Accessory
Module. Reference the Accessory Module manual, p/n 238-47878-00, for more
details on this control.
16

Page 17
Note: The Burner Maintenance section replaces pages 31-33 in the Defender
Atmospheric service manual, p/n 238-44943-00.
Burner Inspection
At periodic intervals (every 6 months), a visual inspection should be made of the pilot
and main burner for proper operation and to assure no debris is accumulating. The
pilot flame should be stable. Some causes for an unstable pilot flame are:
a) Gas pressure is out of specification.
b) Pilot flame not fully engulfing spark/flame sensor.
The main burner should light smoothly from the pilot and burn with a blue flame with a
minimum of yellow tips.
Steel burner models self adjust air to gas ratio mixture and do not have an adjustable
air shutter. The main burner must be free from any debris accumulation that may
effect burner operation (See Burner Cleaning Procedure on page 17).
Burner Cleaning Procedure
Step 1. Move the gas control power switch to the “OFF”
position.
Step 2. Unplug the water heater and Accessory Module from the
wall outlet.
Step 3. Turn off the gas supply to the water heater.
Step 4. Remove the outer door.
Burner Maintenance
Gas control power
switch
Water heater power cord and
Accessory Module transformer
Outer door
17

Page 18
Burner Cleaning Procedure (cont’d)
Step 5. Remove the (4) 1/4” hex drive screws holding the
right side inner door in place.
Step 6. Disconnect the pilot tube
using a 7/16” wrench and the main burner
feedline with a 3/4” wrench from the gas
control.
Step 7. Disconnect the spark igniter/flame sensor wire from
gas control.
Step 8. Remove the burner assembly from the combustion
chamber.
Step 9. Thoroughly inspect the burner surface area and
burner port area and remove any loose debris.
Step 10. Unscrew the burner from the main burner orifice.
Step 11. Remove the main burner orifice from the main
feedline using a 1/2” wrench. Inspect the orifice and clean or
replace, if necessary.
Burner Maintenance
(4) 1/4” hex drive
screws Right side
inner door
Pilot and main
feedlines
Spark igniter/flame
sensor wire
Gas control
Burner assembly
Burner surface area
and burner ports
1/2” wrench
Main burner
orifice
Main feedline
18

Page 19
Burner Cleaning Procedure (cont’d)
Step 12. Re-assemble the burner assembly and re-install into the water heater.
Restore gas supply and check for gas leaks.
Step 13. To resume operation, follow the instructions located on the water heater
lighting instruction label. Or, use the lighting instructions located in the water heater
Installation and Operation manual.
Pilot Inspection, Testing, and Replacement
Note: The Pilot Maintenance section replaces page 13 in the Defender Atmospheric
service manual, p/n 238-44943-00.
Step 1. Move the gas control power switch to the “OFF”
position
Step 2. Unplug the water heater and Accessory Module from the
wall outlet.
Step 3. Turn off the gas supply to the water heater.
Step 4. Remove the outer door.
Step 5. Remove the (4) 1/4” hex drive screws holding the
right side inner door in place.
Burner Maintenance
Gas control power
switch
Outer door
(4) 1/4” hex drive
screws Right side
inner door
Water heater power cord and
Accessory Module transformer
19

Page 20
Pilot Inspection, Testing, and Replacement (cont’d)
Step 6. Disconnect the pilot tube
using a 7/16” wrench and the main burner
feedline with a 3/4” wrench from the gas
control.
Step 7. Disconnect the spark igniter/flame sensor wire from
gas control.
Step 8. Remove the burner assembly from the combustion
chamber.
Step 9. Remove the pilot assembly from the main feedline
using a 1/4" nut driver.
Step 10. Visually inspect the spark igniter/flame sense wire for damage. Replace
the pilot assembly, if damage is found.
Step 11. With a multi-meter set to the ohms setting, check
continuity through the spark igniter/flame sense wire. Replace
the pilot, if there is no continuity.
Pilot Maintenance
Pilot and main
feedlines
Spark igniter/flame
sensor wire
Gas control
Burner assembly
Pilot assembly
1/4” nut driver
Multi-meter
20