Bradford White UPDX series User manual

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Manual 238-49399-00A
SERVICE
MANUAL
Troubleshooting Guide
and Instructions for Service
(To be performed ONLY by
qualified service providers)
Models Covered
by This Manual:
UPDX250T*FRN
UPDX265T*FRN
UPDX275T*FRN
UPDX50S50FR*N
UPDX65S55FR*N
UPDX75S55FR*N
(*) Denotes Warranty Years
Ultra Low NOx Power Direct Vent
Gas Water Heaters
UPDX Series

Bradford White
UPDX Series
Ultra Low NOx Power Direct Vent Gas Water
Heaters
Table of Contents
PageUPDX Service Procedure
Introduction 4 - - -
How to Use This Manual 5 - - -
Tool Required for Service 5 - - -
Specifications 6 - - -
Control Timings 8 - - -
Sequence of Operation 9 - - -
Troubleshooting 12 - - -
Burner Inspection, Cleaning and Replacement 16 I
Pilot Testing, Cleaning and Replacement 18 II
Pressure Switch Testing and Replacement 19 III
Blower Testing and Replacement 21 IV
Blower Temperature Switch Testing and Replacement 23 V
Gas Control & Thermal Well Testing & Replacement 25 VI
- Brass Well (WV4460) to Brass Well (WV4460)
(Models with serial number starting “J” or earlier)
Gas Control Replacement 29 VII
- Brass Well (WV4460) to Polymer Well (WV4462)
(Models with serial number starting “J” or earlier)
Gas Control Testing and Replacement 31 VIII
- Polymer Well (WV4462) to Polymer
Well (WV4462)
(Models with serial number starting “K” or later)
Flammable Vapor Sensor Testing & Replacement 32 IX
Safety Circuit Voltage Trace 33 X
115VAC Circuit Trace 34 XI
Dip Tube Inspection and Replacement 35 XII
Anode Inspection and Replacement 36 XIII
Flue Baffle Inspection and Replacement 39 XIV
Inner Door Removal, Inspection & Replacement 40 XV
Glossary of Terms 42 - - -
Parts List 43 - - -
Page 2
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
Do not try to light any appliance.
x Do not touch any electrical switch; do not use any
phone in your building.
x Immediately call your gas supplier from a neighbor's phone.
Follow the gas supplier's instructions.
x 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.
FOR YOUR SAFETY
Do not store or use gasoline or other flammable,
combustible, or corrosive vapors and liquids in the
vicinity of this or any other appliance.
CAUTION
Incorrect operation of this appliance may
create a hazard to life and property and
will nullify the warranty.
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.
IMPORTANT
Beforeproceeding, please inspectthe
water heater and its components for
possible damage. DO NOT install any
water heater with damaged components.
Ifdamage isevident then please contact
thesupplier wherethewater heater was
purchased or themanufacturer listed on
therating plate for replacement parts.
WARNING
Water heatersareheat producing appliances. To avoid
damage or injury, donot storematerials against the
water heater or vent-air intakesystem. Use proper care
to avoid unnecessary contact(especially by children) with
thewater heater and vent-air intakecomponents.
UNDER NO CIRCUMSTANCES MUST FLAMMABLE
MATERIALS, SUCH AS GASOLINE OR PAINT THINNER BE
USED OR STORED IN THE VICINITY OF THIS WATER
HEATER, VENT-AIR INTAKE SYSTEM OR IN ANY
LOCATION FROM WHICH FUMES COULD REACH THE
WATER HEATER OR VENT-AIR INTAKE SYSTEM.
WARNING
DO NOT ATTEMPT TO LIGHT ANY GAS APPLIANCE IF YOU
ARE NOT CERTAIN OF THE FOLLOWING:
x Liquefied petroleum gases/propane gas and natural gas
have an odorant added by the gas supplier that aids in
the detection of the gas.
x Most people recognize this odor as a “sulfur” or “rotten
egg” smell.
x Other conditions, such as “odorant fade” can cause the
odorant to diminish in intensity, or ”fade”, and not be
as readily detectable.
x 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.
CAUTION
Ifsweat fittings areto be used DO NOT apply heat to the
nipples on top of thewater heater. Sweat thetubing to
theadapter beforefitting theadapter to thewater
connections. Itisimperativethat heat isnot applied to
thenipples containing aplastic liner. WARNING
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.
WARNING
Hydrogen gas can be produced inan operating water
heater that has not had water drawnfrom thetank for a
long period of time(generally twoweeksor more).
Hydrogen gas isextremely flammable. To prevent the
possibility of injury under these conditions, we
recommend thehot water faucet to be open for several
minutes at thekitchen sink beforeyou use any electrical
appliancewhich isconnected to thehot water system. If
hydrogen ispresent, therewill be an unusual sound such
as air escaping through thepipes as hot water begins to
flow. Donot smokeor haveopen flamenear thefaucet
at thetimeitisopen.
CAUTION
Turnoff or disconnecttheelectrical power supply to the
water heater beforeservicing. Label all wires prior to
disconnection when servicing controls. Wiring errorscan
cause improper and dangerousoperation. Verify proper
operation after servicing.
Page 3
UPDX Series
3

Page4
UPDX Series
Introduction
The new Bradford White UPDX2 water heaters are designed to provide reliable performance
with enhanced standard features.New design features include reliable sparkto pilot ignition
system, enhanced diagnostics, simplified servicing, significantly quieter operation, additional
vent lengths, certified FVIR technology and Ultra Low NOx emissions.
SparktoPilot Ignition System-Employing the sparkto pilot ignition system promotes
reliable and consistent pilot and main burner ignitions to provide hot water on demand.
Integrated Immersion Thermostat/GasControl Valvewith LED -Was developed for ease
of troubleshooting by providing simple diagnostic codes to pinpoint an installation or
component performance issue.
Powerful Blower -Will eliminate problems with difficult venting situations.
Quieter and Cooler Blower Operation -Blower noise is significantly reduced for both
interior and exterior environments.Cooler operation increases blower life by reducing bearing
wear and noise.
RuggedWiring Connections-Receptacle type connections promote error free wiring.
IncreasedV
ent Lengths-Increased venting performance is achieved while maintaining
Energy Factor & First Hour Supply performance.
The UPDX2 water heaters use a combustion system where flue gases are combined with
dilution air to reduce the flue gas temperature in the blower, combustion air and dilution air are
drawn from outside the building.The diluted flue gases are evacuated to the exterior through
low temperature vent materials.The gas control maintains water temperature, ignition
sequence and regulates gas flow.A safety circuit consisting of a pressure switch and blower
temperature switch verifies proper conditions exist for safe and reliable operation.If a situation
outside of normal operating parameters exists, the gas control diagnostic LED will flash a code
to identify an operational issue.
This service manual is designed to facilitate problem diagnosis and enhance service efficiency.
To further promote quicker service times the new gas control can be removed and replaced
without draining the water heater.A special tool is required and will be provided with each gas
valve kit shipped from our Service Parts department.
Please read the service manual completely before attempting service on this new series of
power direct vent models.
How the Safety System Works
During normal operation, air for combustion is drawn into the water heater through the intake
vent pipe from outside your building.The air travels into the closed combustion chamber.The
air then mixes in a normal manner with supplied gas and is efficiently combusted, producing
Ultra Low NOx emissions.
In the unlikely event trace amounts of flammable vapors are present in the area surrounding the
water heater, the sealed combustion system prevents the flammable vapors from reaching the
ignition source.In addition the flammable vapor sensor will stop the water heater from
operating if a significant amount of flammable vapors are present.
4

Tools Required for Service
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 UPDX Series water heaters. Understanding the
sequence of operation section of this manual will contribute greatly to troubleshooting the water
heater.
The Honeywell Gas Control will display error codes in the event of abnormal operation. Error
codes are listed in the troubleshooting chart beginning on page 12 of this service manual. The
troubleshooting chart will also indicate the probable cause for the error code and direct the service
professional to a service procedure to properly diagnose the abnormal operation.
In some difficult to diagnose conditions, it may be necessary to isolate the heater from the vent
system to determine the problem.
Contact the Bradford White technical support group immediately if diagnosis cannot be made
using the methods described in this service manual.
Page5
Manometer:Aliquid “U” tube type or adigital 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 damageor simply
not be effective to obtain certain voltageand 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. Anaccurate thermometer is
recommended.
Water Pressure Gauge: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 part number 239-45991-00.A specialized tool designed to remove
the gas control from gas control thermal well. Available from
your Bradford White parts supplier.
Various Hand Tools:Pipe wrench, channel locks, open end wrenchs (3/8",7/16",½"),
12" crescent wrench, Allen wrench set, screw drivers (slotted &
Phillips), ¼" 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
UPDX Series
5

Specifications
Thermal well ECO LimitResidential 188°F (87°C), Commercial 199°F (93°C)
Residential Temperature
SetPoint Range60°F (16°C) to 160°F (71°C) (Approximate temperatures)
Blower TemperatureSwitch Normally closed, opens @ 155°F (68°C), auto reset @ 128°F (54°C).
Blower115VAC, 60Hz,3.1 amps.
Pressureswitch
Standard Altitude-Normally open, closes at differentialpressure of -.80.
High Altitude-Normally open, closes at differentialpressure of -.73.
Power supply Dedicated 115VAC, 60 Hz, 15A
Approved Gas TypeNatural. Unitmust match gas typesupplied.
VentingSystemPower directvent through thewall or vertical through theroof
Approved Vent Materials PVC, CPVCor ABS
Gas Supply PipeMinimum 1/2"NPT(schedule 40black iron piperecommended)
Minimum Clearance
for Servicing18" from top, 24"from front, 4"sides and rear.
Water Supply Pressure150 PSI maximum allowable workingpressure. Check local codes for supply pressure
Gas Pressure6.0" W.C. min. for Nat gas, 11.0" W.C. min. for L.P. gas, 14.0" W.C. maximum (Nat. &L.P.)
Commercial Temperature
SetPoint Range80°F (27°C)to 180°F (82°C)(Approximate temperatures)
Page6
UPDX Series
6

Specifications
Venting Specifications for:
48 Gallon
65 Gallon
75 Gallon
This water heater is approved for installation withthe following PVC, CPVC or ABS
Schedule 40 venting material.
The maximum and minimum vent lengths listed in thistable are for theexhaust portion of
the vent. The intake portion of the vent must be equal to or less than the lengthof the
exhaust.
Through the Wall
Terminating # of
Elbows Maximum
Length ft (m)
Minimum
Length ft (m)
3" Diameter (7.6 cm) PVC Vent Connector Lengths
155 (16.8) 2 (.6)
Through the Wall 2 50 (15.2) 2(.6)
Through the Wall 3 45 (13.7)2(.6)
Through the Wall 4 40 (12.2) 2(.6)
Through the Wall
Terminating # of
Elbows Maximum
Length ft (m)
Minimum
Length ft (m)
4" Diameter (10.2 cm) PVC Vent Connector Lengths
1 95(29.0)10 (3.1)
Through the Wall 2 90(27.4)10(3.1)
Through the Wall 3 85 (25.9)10(3.1)
Through the Wall 4 80 (24.4)10(3.1)
Through the Roof 060 (18.3) 7 (2.1)
Through the Roof 155 (16.8)7 (2.1)
Through the Roof 2 50 (15.2) 7(2.1)
Through the Roof 3 45 (13.7)7(2.1)
Through the Roof 0 100 (30.5) 15(4.6)
Through the Roof 195(29.0) 15(4.6)
Through the Roof 2 90(27.4)15(4.6)
Through the Roof 3 85 (25.9)15(4.6)
Through the Wall 5 75 (22.9)12(3.6)
Through the Roof 4 80 (24.4)15(4.6)
Page 7
UPDX Series
Maximum
Length ft (m)
Minimum
Length ft (m)
45(13.7) 2(.6)
40(12.2)2(.6)
35 (10.7)2(.6)
30 (9.1)2(.6)
50 (15.2)7 (2.1)
45(13.7) 7 (2.1)
40(12.2)7(2.1)
35 (10.7) 7(2.1)
Maximum 75gal.Maximum 48,65gal.
Maximum 75gal.Maximum 48,65gal.
Maximum
Length ft (m)
Minimum
Length ft (m)
85(25.9)10 (3.1)
80 (24.4) 10(3.1)
75(22.9)10(3.1)
70 (21.3) 10(3.1)
90 (27.4) 15(4.6)
85(25.9)15(4.6)
80 (24.4) 15(4.6)
75(22.9)15(4.6)
65(19.8)12(3.6)
70 (21.3) 15(4.6)
7

Control Timings
Ignition State Timing
Pre-purge15Seconds
Trial for Ignition 90 Seconds
FlameStabilization Period3Seconds
Inter-purge15Seconds
FlameFailureResponse Time1.5Seconds(2second maximum; 1second minimum.)
Post-purge15Seconds
PS Fault Delay (failed open/close) Retry after 2Minutes
Soft LockoutRetry after 5Minutes
ECO LimitLockoutIndefinite (cycle power to restart)
Simulated ResistiveLoad LockoutIndefinite (cycle power to restart)
HardwareError LockoutIndefinite (self clearsiffault clearsfor at least 15seconds)
Verify ResistiveDelay Retry after 2Minutes (repeats 5times)
Control Timings
Page8
UPDX Series
8

Sequence of Operation
1. Thermostat Calls for Heat.
Prior to energizing the blower,the gas control checks the safetycircuittoinsure the circuitisopen. Normal switch
positionsin the safetycircuit are as follows:
a) Pressure switchnormallyopen.
b)Blower temperature switchnormallyclosed.
If the safetycircuitisclosed, the gas control waits 4 seconds,thenthe gas control LED flashes 2times followedby
a3second pause. The gas control waits 2minutes then, the blower runs for 30 seconds. Thiscycle repeats until
the safetycircuitopens.
Power Up Sequence
1. Start Up.
Uponpower up, the control runs a safe-start checkwithatypical start-up delayof 1-5 seconds.
2.Flammable Vapor Check.
To assure no outputs are energized if the “Flammable Vapor Sensor” is out of range,the control will test the
“Flammable Vapor Sensor” for proper operating range.If the “Flammable Vapor Sensor” is within range the
control resumes normal operationwith noperceptible delay.If the “Flammable Vapor Sensor” is out of range,the
control LED immediatelyflashes 7 times followedbya3second pause.
Normal Heating Sequence
2.Blower Energizes.
4. Differential Pressure SwitchProves Blower/VentSystem Operation.
a) If the pressure switchdoes not close within 30 seconds,the control LED Flashes 3 times followedbya3second
pause.
b) The blower runs for 30 seconds every2minutes trying to get the pressure switchorblower temperature
switchtoclose. Thiscycle repeats as long as there isacall for heat.
3. Blower Pre-purgePeriod(15 seconds).
5. Trial for Pilot Ignition(90 seconds).
a) The gas control lights the pilot by activating the spark igniter and gas flowto the pilot burner.
b) If flame isnot sensedwithin 90 seconds,the igniter and gas floware deactivated. The blower will post purgeand
the gas control LED flashes 6 times followedbya3second pause.
6.Main Burner Ignition
After pilot flame issensed, the gas control activates the main valve for main burner ignition. The gas control will
ignore flame and pressure switchsignals for 3 seconds allowing for the main burner to stabilize.
Page9
UPDX Series
9

7. Steady State Operation.
Duringsteady state operation thegascontrol monitors:
Thermostat Temperature Sensor-When thesetpoint temperature issatisfied,thegascontrol is shutdown
and theblower will postpurgefor 15seconds.Thegascontrol LED flashesashort flash onceevery 4
seconds(idle) status code.
Pressure Switch /Blower Temperature Switch-Ifeither switch opensthe pilot valve and main valve are
shutdown. Theblower continuesto runfor 30 secondsattemptingto closethecircuit. Thecontrol LED
flashes3 times followed bya3second pause.
Flame Sense-Ifflameislost,the pilot & main valve are shutdown and theblower runsfor 15seconds.The
gascontrol attemptsto re-lightthe pilot 4 times.Ifunsuccessful,theblower is shutdown and thegascontrol
proceedstoa5minute lockout. Thegascontrol re-attemptsto lightthe pilot startingat normal heating
sequence#2.
8.Thermostat Satisfies.
9. Burner Off.
10. Blower Post-purge(15seconds).
Sequence ofOperation
Abnormal Operation
1.Flammable Vapor Sensor Fault:
a)If the FlammableVapor Sensor Resistance is Greater than 70,000 Ohms -thegascontrol immediately turns
off all outputs.Thegascontrol waitsand monitorsresistancefor 30 seconds.Iftheresistanceisgreater than
70,000 ohms after 30 seconds, thegascontrol proceedsto verifyresistive delay for 2minutesand flashes7 times
followed by a3second pause. Thisprocess isrepeated 5 timesuntil thegascontrol either returnsto normal
operation or proceedstoalockoutmode flashing7 times followed bya3second pause.
b) If the FlammableVapor Sensor Resistance is Below 3000 ohms -Thegascontrol immediately turnsoff all
outputsand proceedsto flash 8 times then 1 time followed bya3second pause. The error selfclearsifthe
resistance returnsto the normal rangefor at least15seconds.
Normal HeatingSequence(continued)
2.Temperature Sensor Fault:
a)Temperature Sensor Detected Open Circuit -Thegascontrol Immediately turnsoff all outputsand proceedsto
flash 8 timesthen3timesfollowed bya3second pause. The error selfclearsifthefault clearsfor at least15
seconds.
b) Temperature Sensors not Reading the Same Temperature Within ±5.5°F - Thegascontrol immediately turns
off all outputsand proceedsto flash 8 times then 3 times followed bya3second pause. The error selfclearsifthe
fault clearsfor at least15seconds.
c) Water Temperature in Excess ofECO(EnergyCut Out)limit -Thegascontrol immediately turnsoff the pilot
and main valve and proceedsto flash 4 times followed bya3second pause. Blower continuesto rununtil thegas
control isreset. Theset point knobshould beturned to theminimum temperature settingfor at least6seconds
and then turned clockwiseby45
o.
Page10
UPDX Series
10

Sequence of Operation
AbnormalOperation (cont.)
3.Pressure Switch/Blower Temperature Fault:
a) PressureSwitchClosedat StartofCall forHeat - Thegascontrolwaits4secondsthen, proceedsto flash
2 timesfollowed by a 3 second pause.Thegascontrolwaits2 minutesand then turnson theblower for 30
seconds. Theblower turnsoff after 30secondsand thegascontrolwaitsfor the pressure switchto open.Any time
the pressure switchopens,theblower turnson (or stayson) and the controlproceedsto waiting for the pressure
switchto close.
b) PressureSwitchorBlowerTemperatureSwitchFailedOpen - Thegascontrolrunstheblower for 30seconds
waiting for the pressure switchand/or blower temperature switchto close.If either switchdoesnot closein30
seconds,theblower turnsoff and the controlflashes3 timesfollowed by a 3 second pause.Thegascontrolwaits
2 minutesbefore turning on theblower for another 30secondsto see the circuit close.Thiscycle repeatsaslong
asthere isacall for heat or untilthe circuit closes.
c) PressureSwitchorBlowerTemperatureSwitchOpensDuringBurnerOperation - Thegascontrolturnsoff
thepilot and main valve, runstheblower for 15seconds(inter-purge) waiting for the pressure switchand/or blower
temperature switchto close.If either switchfails to close, thegascontrolproceedsasdescribed in 3b above.Ifthe
circuit closesagain by the end of the inter-purge, the recyclecounter isincremented, if the recyclecount has
not reached itslimit (4), another trialfor ignition begins. Ifthe recyclecount hasbeen reached, the control
turnsoff theblower and flashes6 times then 2 times followed by a 3 second pause.Thegascontrolwaits5
minutesbefore repeating ignition sequence.
4. TrialFor Ignition Fault:
a) PressureSwitchOpensDuringTrial - Thegascontrolturnsoff the igniter and pilot valve.Thegascontrol
proceedsasdescribed in 3b above.Ifthe pressure switchcloseswithin 30seconds,thegascontrolwill continue
withtrialfor ignition starting at blower pre-purge.
b) Flame Not Sensed-Thegascontrolenergizesthesparkigniter attempting to lightthepilot and prove flame.If
flame isnot sensed within 90seconds,the igniter turnsoff, thepilot valve isclosed and thegascontrolrunsthe
blower throughpostpurge and flashes6 times then once followed by a 3 second pause.The controlwaits5
minutesbefore repeating the ignition sequence.
5. Flame Sensing Fault:
a) FlameLostDuringRun - Thegascontrolturnsoff thepilot and main valvesand runstheblower for 15seconds
(inter-purge).Thegascontrolincrementsthe recyclecount, if the recyclecount hasnot reached itslimit (4),
another trialfor ignition begins. Ifthe recyclecount hasbeen reached, thegascontrolturnsoff theblower and
flashes6 times then 3 times followed by a 3 second pause.The controlwaits5minutesbefore repeating the
ignition sequence.
b) Flame SensedOut of Sequence - thegascontrolonlylooks for pilot flame when theblower isrunning.Ifaflame
ispresent when thepilot valve isnot open the controlproceedsto wait for flame loss and flashes5 times followed
by a 3 second pause.Thiscontinuesuntilflame islost, once theflame signalislost, thegascontrolflashes6
times then 4 times followed by a 3 second pause.Thegascontrolwaits5minutesbefore repeating the ignition
sequence.
Page11
UPDX Series
11

Shortflash, onceevery
four seconds
“Heartbeat”, alternates
bright/dim
Thermostat calling
for heat (no fault).
Shortflash onceper
second
Weak pilot signal
on last call for heat.
Twoflash, three second
pause
Pressureswitch not
working-closed
position.
Three flash, three second
pause
Pressureswitch or
blower temp.
switch not working
-open position.
Four flash, three second
pause
Excessive tank
temperature.
System mustbe
reset.
Fiveflash, three second
pause
Undesired-false
pilot flamepresent.
Troubleshooting
LEDStatus
Stand-by mode,
Waitingfor call for
heat (no fault).
Control Status Service
Procedure
Probable Cause
Temperaturedemand issatisfied
Normal operation.
Adjust thermostat to
desired temp. level.
Tank temperaturebelow setpoint of thermostat.
Normaloperation.
Adjustthermostat to
desiredtemp.level.
1.Unstablepilot.
2.Pilot tube blockedor restricted.
3. Oxidation builduponpilot electrode.
4. Wire damagetopilot assemblyor bad
connection at gasvalve.
1-4. Page 18
1.Pressure switchtubingkinkedor blocked.
2.Blockedpressure tap on switchor blower.
3. Faultypressure switch.
1-3. Page 19
1.Vent blockageorimproper vent configuration.
2.Pressure switchtubingkinkedor blocked.
3. Faultypressure switch.
4. Blower not spinninguptospeed.
5. Blower temp or exhaust temp too high
6. Faultyblower temperature switch.
7. Intakevent lengthexceeds exhaustvent length.
8. Frozen intakeorexhaustvent terminal.
1. Check vent or vent tables
2 & 3. Page 19
4. Page 21
5 & 6. Page 23
8. Page 41
1.Thermalwell sensor outofcalibration.
2.Faultygascontrol.
3. Plumbingleak
1. Page 25
2. Replace gas control,
page 27&29
1.Pilot valvestuckin open position.1. Replace gas control,
page 27&29
None, control LED not on
or flashing
Noelectrical
power
Control power switch in“OFF”position.
Supply voltageinterrupted. Turnpower on.
Page12
Observe green LED indicator on gas control.
Error flash codes are displayed with athree
second pause before repeating. Check and
repair the system as noted in the
troubleshooting table below.
Green LED
Indicator
UPDX Series
(For models with serial numbers starting with K or later see chart on page 15.)
12

Six-four flash, three
second pause
Undesired-false
pilot flame
sensed.
System auto
resets.
Seven flash, three second
pause
FlammableVapor
Sensor fault
detected
Eight-one flash, three
second pause
FlammableVapor
Sensor outof
specification.
Thermalwell
sensor damaged
or unplugged
Eight-three flash, three
second pause Gasvalve
electronicsfault
detected
LED Status Control Status Service
Procedure
Probable Cause
Pilot valvestuckin open position.Replace gas control,
page 27or 29
WARNING:EXPLOSIONHAZARD
*Indicatesgasoline vaporswere detectedat potentially
explosivelevels.
*Verify no gasoline vaporsare still present
*Reset the controlbycyclingpower to the appliance or
bycyclingtheON/OFF switch.
*Replace theFlammableVapor Sensor element if a
gasoline spill event occurred.
Page 32
*Verify FlammableVapor Sensor (FVS)resistance is
not below25KOhms.
*Checkwiringto FVSandconfirm itis not shorted.
*Replace controlif everythingabovechecksoutOK.
Page 32
1.Damagetothermalwell wire.
2.Thermalwell sensor resistance outofrange.Page 25
1.Controlneeds to be reset.
2.Controlis wet or physicallydamaged.
1. Interrupt power supply
2. Replace gas control,
page 27or 29
Eight-four flash, three
second pause
Gasvalvefault
detected.
1.Controlneeds to be reset.
2.Controlis wet or physicallydamaged.
1. Interrupt power supply
2. Replace gas control,
page 27or 29
Troubleshooting
Six-three flash, three
second pause
Pilot flame
extinguished.
System auto
resets.
1.Unstablepilot.
2.Pilot tube blockedor restricted.
3. Oxidation builduponpilot electrode.
4. Wire damagetopilot assemblyor bad
connection at gasvalve.
5. Insufficient combustion air.
6. Gaspressure is outo
fspecification.
1-4. Page 18
5. Refer to installation manual
Page13
Six-twoflash, three
second pause
Pressure switch
or blower temp
switchopened
duringburner
operation.
System auto
resets.
1. Check vent or vent tables.
2 & 3. Page 19
4. Refer to venting section of
installation manual
5. Page 21
6&7. Page 23
8. Refer to installation
manual.
1.Vent blockageorimproper vent configuration.
2.Pressure switchtubingkinkedor blocked.
3. Faultypressure switch.
4. Vent termination beingaffectedbywind
5. Blower not spinninguptospeed.
6. Blower temp.or exhaust temp.too high
7. Faultyblower temperature switch.
8. Insufficient combustion air.
Six-one flash, three
second pause
Failed to lightpilot.
System auto resets.
1.Unstablepilot.
2.Pilot tube blockedor restricted.
3. Oxidation builduponpilot electrode.
4. Wire damagetopilot assemblyor bad
connection at gasvalve.
1-4. Page 18
UPDX Series
13

Shortflash, onceevery
four seconds
“Heartbeat”, alternates
bright/dim
Thermostat calling
for heat (no fault).
Shortflash onceper
second
Weak pilot signal
on last call for heat.
Twoflash, three second
pause
Pressureswitch not
working-closed
position.
Three flash, three second
pause
Pressureswitch or
blower temp.
switch not working
-open position.
Four flash, three second
pause
Excessive tank
temperature.
System mustbe
reset.
Fiveflash, three second
pause
Undesired-false
pilot flamepresent.
LED Status
Stand-by mode,
Waitingfor call for
heat (no fault).
Control Status Service
Procedure
Probable Cause
Temperaturedemand issatisfied
Normal operation.
Adjust thermostat to
desired temp. level.
Tank temperaturebelow setpoint of thermostat.
Normaloperation.
Adjustthermostat to
desiredtemp.level.
1.Unstablepilot.
2.Pilot tube blockedor restricted.
3. Oxidation builduponpilot electrode.
4. Wire damagetopilot assemblyor bad
connection at gasvalve.
1-4. Page 18
1.Pressure switchtubingkinkedor blocked.
2.Blockedpressure tap on switchor blower.
3. Faultypressure switch.
1-3.Page 19
1.Vent blockageorimproper vent configuration.
2.Pressure switchtubingkinkedor blocked.
3. Faultypressure switch.
4. Blower not spinninguptospeed.
5. Blower temp or exhaust temp too high
6. Faultyblower temperature switch.
7. Intakevent lengthexceeds exhaustvent length.
8. Frozen intakeorexhaustvent terminal.
1. Check vent or vent tables.
2&3.Page 19
4. Page 21
5&6.Page 23
8. Page 41
1.Thermalwell sensor outofcalibration.
2.Faultygascontrol.
3. Plumbingleak
1-2.Replacegas control,
page 31
1.Pilot valvestuckin open position.1. Replacegas control,
page 31
None, control LED not on
or flashing
Noelectrical
power
Control power switch in“OFF”position.
Supply voltageinterrupted. Turnpower on.
Observe green LED indicator on Electronic gas
control. Error flash codes are displayed with a
three second pause before repeating. Check
and repair the system as noted in the
troubleshooting table below.
Green LED
Indicator
TroubleshootingUPDX Series
Page14
(The following chart is for models with serial numbers starting with K or later.)
14

Page16
Six-four flash, three
second pause
Undesired-false
pilot flame
sensed.
System auto
resets.
Sevenflash, three second
pause
FlammableVapor
Sensor fault
detected
Eight-oneflash, three
second pause
FlammableVapor
Sensor outof
specification.
Eight-three flash, three
second pause
Gasvalve
electronicsfault
detected
LED Status Control Status Service
Procedure
Probable Cause
Pilot valvestuckin open position.Replace gas control,
page 31
WARNING:EXPLOSIONHAZARD
*Indicatesgasoline vaporswere detectedat potentially
explosivelevels.
*Verify no gasoline vaporsare still present
*Reset the controlbycyclingpower to the appliance or
bycyclingtheON/OFF switch.
*Replace theFlammableVapor Sensor element if a
gasoline spill event occurred.
Page 32
*Verify FlammableVapor Sensor (FVS)resistance is
not below25KOhms.
*Checkwiringto FVSandconfirm itis not shorted.
*Replace controlif everythingabovechecksoutOK.
Page 32
1.Controlneeds to be reset.
2.Controlis wet or physicallydamaged.
1. Interrupt power supply
2. Replace gas control,
page 31
Eight-four flash, three
second pause
Gasvalvefault
detected.
1.Controlneeds to be reset.
2.Controlis wet or physicallydamaged.
1. Interrupt power supply
2. Replace gas control,
page 31
Six-three flash, three
second pause
Pilot flame
extinguished.
System auto
resets.
1.Unstablepilot.
2.Pilot tube blockedor restricted.
3. Oxidation builduponpilot electrode.
4. Wire damagetopilot assemblyor bad
connection at gasvalve.
5. Insufficient combustion air.
6. Gaspressure is outo
fspecification.
1-4. Page 18
5. Refer to installation manual
Six-twoflash, three
second pause
Pressure switch
or blower temp
switchopened
duringburner
operation.
System auto
resets.
1. Check vent or vent tables.
2&3. Page 19
4. Refer to venting section of
installation manual
5. Page 21
6&7. Page 23
8. Refer to installation
manual.
1.Vent blockageorimproper vent configuration.
2.Pressure switchtubingkinkedor blocked.
3. Faultypressure switch.
4. Vent termination beingaffectedbywind
5. Blower not spinninguptospeed.
6. Blower temp.or exhaust temp.too high
7. Faultyblower temperature switch.
8. Insufficient combustion air.
Six-oneflash, three
second pause
Failed to lightpilot.
System auto resets.
1.Unstablepilot.
2.Pilot tube blockedor restricted.
3. Oxidation builduponpilot electrode.
4. Wire damagetopilot assemblyor bad
connection at gasvalve.
1-4. Page 18
Troubleshooting
UPDX Series
Eight-twoflash, three
second pause
Temperature
sensor damaged
or unplugged
1.DamagetoTemperature Sensor.
2.Thermalwell sensor resistance outofrange.
1&2. Replace gas control,
page 31
Page15
15

UPDX SERVICEPROCEDUREI
Burner Operation Inspection, Cleaning and
Replacement
Page16
UPDXSeries
At periodic intervals (not more than 6 months), a visual inspection should be made of the main burner for proper
operation and to insure no debris is accumulating.
Main burner should light smoothly from pilot and burn with a blue flame with a minimum of yellow tips.After 5 minutes
of operation the burner screen will become radiant and the flame will soften and turn orange.If the burner screen does not
become radiant after 5 minutes of operation, it must be cleaned (see burner cleaning procedure below).
Main burner must be free from any debris accumulation that may affect burner operation (see burner cleaning procedure
below).
Main Burner Inspection,Cleaning and Replacement
DANGER
Under no circumstances shall flammable materials be used or stored in thevicinityofthewater heater.With
the inner door removed the Bradford White Defender SafetySystem will be deactivated.Ifflammable vapors
are present,afire or explosion mayresult causing propertydamage,personal injuryor death.
WARNING
Innerdoorandburnercomponents maybe HOT when performingthis operation. Take
necessaryprecaution to prevent personal injury.
Burner Cleaning
Step 1.Remove burner and inner door assembly per UPDX SERVICEPROCEDUREXV, steps 1 through 9.
Step 2.Thoroughly inspect burner screen and burner venturi and remove any loose debris accumulation.Inspect
burner screen for any openings larger than the normal screen openings.
Step 3.Use compressed air and/or a vacuum to remove any scale or other debris accumulation from the burner screen
and venturi.
Burner Venturi
Burner Screen
16

UPDX SERVICEPROCEDUREI
Burner Operation Inspection, Cleaning and
Replacement
Page17
UPDXSeries
Step 10.Reassemble burner and reinstall into water heater.Restore gas supply and checkfor gas leaks.
Step 11.To resume operation follow the instruction located on the lighting instruction label or the lighting
instruction located in the installation and operating manual.
Step 4.Disconnect (unscrew) feedline from the main burner door.
Step 5.Remove main burner orifice from feed line (3/8"wrench).Inspect and
clean if necessary
Step 6.Remove pilot assembly, refer to UPDX SERVICEPROCEDUREII
for cleaning and inspection.
Step 7.Reassemble burner.
Step 8.Reinstall burner and inner door per UPDX SERVICEPROCEDUREXV,
steps 10 through 22.
Step 9.To resume operation, follow the instructions located on the lighting instruction label or the lighting
instructions located in the installation and operation manual.
Feedline
Main Burner Orifice
Main Burner
Door
Burner Cleaning (Continued)
17

UPDX SERVICEPROCEDUREII
Pilot Inspection, Cleaning and Replacement
Step 1.Position gas control power switchto the “OFF”
position and unplug heater from wall outlet.
Step 2.Turn off gas supply to water heater.
Step 3.Remove outer jacket door and remove main burner
per service procedure XV, steps 1 through 9
on page 38.
Step 7.Remove pilot assembly from main burner (¼" nut driver).
Step 8.Visually inspect igniter/flame sense wire for damage.Replace
pilot if damage is found.
Step 9.With a multi-meter set to the ohms setting, checkcontinuity
through igniter/flame sense wire.Replace pilot if no continuity.
Step 10.Visually inspect igniter/flame sense electrode for deterioration.
Replace pilot as necessary.Electrode should not be in contact
with pilot hood, If so, carefully adjust electrode to a gap
distance of 3/32"(0.09") from pilot hood.
Step 11.Visually inspect igniter/flame sense electrode for oxidation
build up.Carefully clean any oxidation using very fine emery
cloth.
Step 14.Reassemble pilot and install to feedline.Reinstall burner
assembly to water heater.Restore gas supply and checkfor gas
leaks.
Step 15 To resume operation follow the instructions located on the
lighting instructions label or the lighting instructions located in the
installation and operation manual.
Step 12.Visually inspect pilot tubing for kinks or cracks.If damage is
found replace pilot.
Step 13.Inspect pilot tubing and pilot orifice for blockage:
a) Remove ferrule nut from bottom of pilot assembly (7/16"
wrench).
b) Remove pilot tube and pilot orifice.
c) Inspect pilot tubing and pilot orifice for blockage.Clean
or replace as necessary.Ferrule
nut
Pilot
orifice
Pilot
hood
Igniter/flame sense
electrode
Igniter/flame sense
wire
Pilot
tubing
Page18
UPDXSeries
Pilot assembly Inspection,Cleaning and Replacement Gas Control shown in the
“OFF” Position
¼” Hex Drive Pilot
Screw
Ferrule Nut
18

UPDX SERVICEPROCEDUREIII
Pressure Switch Testing and
Replacement
Pressure Switch Testing WARNING
115volt potential exposure. Use caution
makingvoltage checkstoavoidpersonal injury.
Step 1.Position gas control power switch
to the “OFF”position.
Step 2.Remove the three screws (Phillips screw driver) from control access cover on blower assembly and
remove cover (see photos 1 and 2).
Step 3.Carefully remove pressure switch from blower housing (see photo 3).
2
Use amulti-meter set to the
ohms setting.With blower off,
check across pressure
switch terminals.
Are switch contacts open
(no electrical continuity)?
Check tubing and pressure tap
on switch for blockage.
Is there blockage?
Replace switch
(see page20).
Position gas valve power
switch to the “ON” position
and adjust thermostat
to call for heat,
this will start the blower.
Check with multi-meter, do
pressure switch contacts close
with blower running with the
switch in the vertical
postition?
With steps 1,2 &3 complete,
disconnect wire leads from
pressure switch.
Y
N
Y
N
Switch contacts are OK.
See safety circuit trace
(page33).
Is vent
system
Blocked?
NSee blower testing
(page21)
Is blower OK?
Clear blockage.
Y
N
Y
N
Correct blower
problem.
Pressure Switch
Slide pressure switch in direction of
arrow while tilting slightly away
from blower housing.
Is vent system length
within vent table
specifications
listed on page7.
Y
Reconfigure vent
system to be
compliant with
vent tables.
N
Y
Pressure Switch
Wire Leads
Page19
Check tubing and
pressure tap on
switch for blockage.
Is there blockage?
N
Y
UPDXSeries
1
3
Control Access
Cover Screws
4
Gas Control shown in the
“OFF” Position
Control Access
Cover
19

Pressure Switch Replacement WARNING
115volt potential exposure. Use caution
to avoidpersonal injury.
Step 6.Reconnect wires from step 5 to new pressure switch.
Step 7.Reconnect tubing to new pressure switch.
Step 8.Carefully position pressure switch into blower housing.
Step 9.Position gas control power switchto “ON”position and verify proper heater operation.
Step 10.Replace control access cover from step 2.
Step 1.Position gas control power switch
to the “OFF”position.
Step 2.Remove the three screws
(Phillips screw driver) from
control access cover on blower
assembly and remove cover
(see photo 5 and 6).
Pressure Switch
Slide pressure switch in direction of
arrow while tilting slightly away
from blower housing.
Step 3.Carefully remove pressure
switch from blower
housing (see photo 7).
Step 4.Disconnect tubing from
pressure switch
(see photo 8).
Step 5.Disconnect yellow wires
from pressure switch
(see photo 9).
UPDX SERVICEPROCEDUREIII
Pressure Switch Testing and
Replacement
Page20
67
8
9
UPDXSeries
Gas Control shown in the
“OFF” Position
5
Control Access
Cover Screws
Control Access
Cover
Tubing
Yellow Wires
20