Bradford-White PDX50S60F-B, PDX250T6-F-BN, PDX265T6-F-BN, PDX75S70F-B, PDX65S65F-B User Manual

Bradford White

PDX Series

Powered Direct Vent Gas Water Heaters

Save this manual for future reference

Manual 46925A

(*) Denotes Warranty Years

SERVICE

MANUAL

Troubleshooting Guide

and Instructions for Service

(To be performed ONLY by qualified service providers)

For Bradford White

PDX Series Models:

PDX250T6*F(BN,CX)
PDX265T6*F(BN,CX)
PDX275T6*F(BN,CX)

PDX50S60F(B,C)*(N,X)
PDX65S65F(B,C)*(N,X)
PDX75S70F(B,C)*(N,X)

Bradford White

PDX Series

Powered Direct Vent Gas Water Heaters

Table of Contents

Page TTW 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 14 I

Pilot Testing, Cleaning and Replacement 16 II

Pressure Switch Testing and Replacement 17 III

Blower Testing and Replacement 21 IV

Blower Temperature Switch Testing and Replacement 23 V

Gas Control & Thermal well Testing & Replacement 25 VI

Flammable Vapor Sensor Testing & Replacement 29 VII

Safety Circuit Voltage Trace 30 VIII

115VAC Circuit Trace 31 IX

Dip Tube inspection and Replacement 32 X

Anode Inspection and Replacement 33 XI

Flue Baffle Inspection and Replacement 34 XII

Inner Door Removal, Inspection & Replacement 35 XIII

Glossary of Terms 38 - - -

Parts List 39 - - -

Page 2

2

WARNING: If the information in these

i

nstructions is not followed exactly, a fire or
explosion may result causing property damage,
p

ersonal injury, or death.

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.

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

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.

WARNING

Water heaters are heat producing appliances. To

avoid damage or injury, do not store materials

against the water heater or vent-air intake system.

Use proper care to avoid unnecessary contact

(especially by children) with the water heater and

vent-air intake components. 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:

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.

CAUTION

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.

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 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 the 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.

CAUTION

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.

Page 3

PDX Series

3

Page 4

Introduction

The new Bradford White PDX2 and PDX 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, significantly quieter
operation, additional vent lengths and certified FVIR technology.

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 Thermostat/Gas Control Valve with LED - was developed for ease
of troubleshooting by providing simple diagnostic codes to pinpoint an installation or
component performance issue.

New 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.

Rugged Wiring Connections - receptacle type connections promote error free wiring.

Increased Vent Lengths - increased venting performance is achieved while maintaining

Energy Factor & FHSR performance.

The PDX2 and PDX water heaters use a combustion system were 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 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 new gas valve 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 vent models.

How the Safety System Works

During normal operation, air for combustion is drawn into the water heater though the vent pipe from outside your
building. The air travels into the closed combustion chamber. The air then mixes with in a normal manner with
supplied gas and its efficiently combusted, producing very 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 vapors sensor will stop the water heater from operating if a significant amount of flammable vapors are
present.

PDX Series

4

Tools Required for Service

It is intended for this manual to be used by qualified service personal for the primary purpose of
troubleshooting and repair of the Bradford White TTW Series 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. 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 can not be made
using the methods described in this service manual.

Page 5

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: A digital 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 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 (common &
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, and flashlight, 5 gallon pail.

H

ow to Use This Manual

PDX Series

5

Specifications

Thermal well TCO Limit Residential 188°F (87°C), Commercial 199°F (93°C)

Residential Temperature
Set Point Range

60°F (16°C) to 160°F (71°C) (Approximate temperatures)

Blower Temperature
Switch

Normally closed, opens @ 165°F (74°C), auto reset @ 130°F (54°C).

Blower 115VAC, 60Hz, 3.1 amps.

Pressure switch

Exhaust-Normally open, closes on vacuum increase @ -1.30.

Intake-Normally closed, opens on vacuum increase @ -1.15.

Power supply Dedicated 115VAC, 60 Hz, 15A

A

pproved Gas Type

N

atural or Propane. Unit must match gas type supplied.

Venting System Power vent through the wall or vertical through the roof

Approved Vent Materials PVC, CPVC or ABS

G

as Supply Pipe

M

inimum 1/2" NPT (schedule 40 black iron pipe recommended)

Minimum Clearance
for Servicing

18" from top, 24" from front, 4" sides and rear.

Water Supply Pressure 150 PSI maximum allowable working pressure. Check local codes for supply pressure

Gas Pressure 5.0" 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
Set Point Range

80°F (27°C) to 180°F (82°C) (Approximate temperatures)

Page 6

PDX Series

6

S

pecifications

V

enting Specifications for:

48 Gallon
65 Gallon
75 Gallon

This water heater is approved for installation with the following PVC, CPVC or ABS
Schedule 40 venting material.

The maximum and minimum vent lengths listed on this label are for the exhaust portion of
the vent. The intake portion of the vent must be equal to or less than the length of 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

1 55 (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 0 60 (18.3) 7 (2.1)

Through the Roof 1 55 (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 1 95 (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)

Vent Tables

Page 7

PDX 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 75 gal.Maximum 48, 65 gal.

Maximum 75 gal.Maximum 48, 65 gal.

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-purge 2 Seconds

Trial for Ignition 90 Seconds

Flame Stabilization Period 3 Seconds

Inter-purge 15 Seconds

Flame Failure Response Time 1.5 Seconds (2 second. Maximum; 1 second minimum.)

Post-purge 15 Seconds

PS Fault Delay (failed open/close) Retry after 2 Minutes

Soft Lockout Retry after 5 Minutes

TCO Limit Lockout Indefinite (cycle power to restart)

Simulated Resistive Load Lockout Indefinite (cycle power to restart)

Hardware Error Lockout Indefinite (self clears if fault clears for at least 15 seconds)

Verify Resistive Delay Retry after 2 Minutes (repeats 5 times)

Specifications

Page 8

Wiring Diagram

PDX Series

8

Sequence of Operation

Thermostat calls for heat.

Prior to energizing blower, gas control checks safety circuit to insure the circuit is open. Normal switch positions
in the safety circuit are as follows:

a) Exhaust pressure switch normally open.
b) Blower temperature switch normally closed.

c) Inlet pressure switch normally closed.
If the safety circuit is closed, the control waits 4 seconds, gas control LED flashes 2 times with 3 second pause.
Gas control waits 2 minutes then, blower runs for 30 seconds. This cycle repeats until safety circuit opens.

Power up Sequence

1

Start Up.

Upon power up, the control runs a safe-start check with a typical start-up delay of 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
the “Flammable Vapor Sensor” for proper operating range. If the “Flammable Vapor Sensor” is within range the
control resumes normal operation with no perceptible delay. If the “Flammable Vapor Sensor” is out of range, the
control LED immediately flashes 7 times with 3 second pause.

Normal Heating Sequence

1

2

Blower energizes.

3

Exhaust pressure switch proves blower/vent system operation.

a) If the pressure switch does not close within 30 seconds, the control LED Flashes 3 times with 3 second pause.

The blower runs for 30 seconds every 2 minutes trying to get the pressure switch or blower temperature switch

to close. This cycle repeats as long as there is a call for heat.

b) The normally closed inlet pressure switch allows the system to work as long as the inlet air is not blocked.

4

Blower pre-purge period (2 seconds)

5

Trial for pilot ignition (90 seconds).

a) The gas control lights the pilot by activating spark igniter and gas flow to pilot burner.
b) If flame is not sensed within 90 seconds, igniter and gas flow are deactivated, blower will post purge and

control LED flashes 6 times with 3 second pause.

6

Main burner Ignition

After pilot flame is sensed, gas control activates main valve for main burner ignition. The gas control will ignore
flame and pressure switch signals for 3 seconds allowing for main burner to stabilize.

Page 9

PDX Series

9

Steady state operation.

During Steady State Operation the Control Monitors:

T

hermostat temperature sensor- When set point temperature is satisfied, gas valve is shut down and

blower will post purge for 15 seconds. Control LED flashes a short flash once every 4 seconds (idle) status
c

ode.

Pressure switch / Blower temperature switch- If either switch opens, pilot valve and main valve is shut
down. The blower continues to runs for 30 seconds attempting to close the circuit. The control LED Flashes
3 times with 3 second pause.

Flame Sense- If flame is lost, pilot & main valve are shut down, blower runs for 15 seconds. Control attempts
to re-light pilot 4 times. If unsuccessful, Blower is shut down and control proceeds to 5 minute lockout. Control
re-attempts to light pilot starting at normal heating sequence #2.

Thermostat satisfies.

Burner off.

Blower post purge (15 seconds).

9

8

10

7

Sequence of Operation

Abnormal Operation

1. Simulated Resistive Device Fault:

a) If the Flammable Vapor Sensor resistance is greater than 70,000 Ohms - the gas control immediately turns

off all outputs. Control waits and monitors resistance for 30 seconds. If the resistance is greater than 70,000 ohms

after 30 seconds, the gas control proceeds to verify resistive delay for 2 minutes and flashes 7 times with a three
second pause. This process is repeated 5 times until the control either returns to normal operation or proceeds
to a lockout mode flashing 7 times with a 3 second pause.

b) If the Flammable Vapor Sensor resistance is below 3000 ohms - The gas control immediately turns off all

outputs and proceeds to flash 8 times then once with three second pause. The error self clears if the resistance
returns to normal range for at least 15 seconds.

Normal Heating Sequence (cont.)

2. Temperature Sensor Fault:

a) Temperature sensor detected open circuit - The gas control Immediately turns off all outputs and proceeds to

flash 8 times then three times with three second pause. The error self clears if the fault clears for at least 15
seconds.

b) Temperature 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 three times with three second pause. The error self clears if the fault
clears for at least 15 seconds.

c) Water temperature in excess of TCO (Temperature Cut Off) limit - The gas control immediately turns off pilot &

main valve and proceeds to flash 4 times with 3 second pause. Blower continues to run until gas control is reset.
Power needs to be cycled to remove gas control from TCO lockout.

Page 10

PDX Series

10

Sequence of Operation

Abnormal Operation (cont.)

3. Pressure Switch/Blower Temperature Fault:

a

) Pressure switch closed at start of call for heat - The control waits four seconds then, proceeds to flash

2 times with 3 second pause. The control waits 2 minutes and then turns on blower for 30 seconds. The blower
turns off after 30 seconds and the control waits for pressure switch to open. Any time the Pressure switch opens,
the blower turns on (or stays on) and the control proceeds to waiting for pressure switch to close.

b) Pressure switch or blower temperature switch failed open - The control runs the blower for 30 seconds

waiting for the pressure switch and/or blower temperature switch to close. If either switch does not close in 30
seconds, the blower turns off and the control flashes 3 times with 3 second pause. The control waits two
minutes before turning on the blower for another 30 seconds to see the circuit close. This cycle repeats as long as
there is a call for heat or until the circuit closes.

c) Pressure switch or blower temperature switch opens during burner operation - The control turns off the

pilot and main valve, runs blower for 15 seconds (inter-purge) waiting for pressure switch and/or blower
temperature switch to close. If either switch fails to close, the control proceeds as described in 3b above. If the
circuit closes again by the end of the inter-purge, the recycle counter is incremented, if the recycle count has
not reached its limit (4), another trial for ignition begins. If the recycle count has been reached, the control
turns off the blower and flashes 6 times then 2 times with 3 second pause. The control waits 5 minutes before
repeating ignition sequence.

d) Normally closed intake pressure switch opens at start of call for heat-the control runs the blower for 30

seconds waiting for the pressure switch to close. If the switch does not close in 30 seconds, the blower turns off
and the control flashes 3 times with a 3 second pause. The control waits two minutes before turning on the blower
for another 30 seconds to see the circuit close. This cycle repeats as long as there is a call for heat or until the
circuit closes.

4. Trial For Ignition Fault:

a) Pressure switch opens during trial - The control turns off igniter and pilot valve. The gas control proceeds

as described in 3b above. If the pressure switch closes within 30 seconds the gas control will continue with trial for
ignition starting at blower pre-purge.

b) Flame Not Sensed - The control energizes the spark igniter attempting to light the pilot and prove flame. If

flame is not sensed within 90 seconds, the igniter turns off, the pilot valve is closed and the gas control runs the
blower through post purge and flashes 6 times then once with 3 second pause. The control waits 5 minutes before
repeating the ignition sequence.

5. Flame Sensing Fault:

a) Flame lost during run - The control turns off pilot and main valves, runs blower for 15 seconds (inter purge).

The 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 control turns off the blower and flashes 6 times
then 3 times with 3 second pause. The control waits 5 minutes before repeating the ignition sequence.

b) Flame sensed out of sequence - the control only looks for pilot flame when the blower is running. If flame is

present when the pilot valve is not open, the 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 3 second pause. The control waits 5 minutes before repeating the ignition sequence.

Page 11

PDX Series

11

Short flash, once every
four seconds

“Heartbeat”, alternates
bright/dim

Thermostat calling
for heat (no fault).

Short flash once per
second

Weak pilot signal
on last call for
heat.

Two flash, three
second pause

Pressure switch
not working­closed position.

Three flash, three
second pause

Pressure switch
or blower temp.
switch not working

-open position.

Four flash, three
second pause

Excessive tank
temperature.
System must be
reset.

Five flash, three
second pause

Undesired-false
pilot flame
present.

T

roubleshooting

LED Status

Stand-by mode,
Waiting for call for
heat (no fault).

Control

Status

Service

Procedure

Probable Cause

Temperature demand is satisfied

Normal operation.

Adjust thermostat to

temp level

Tank temperature below set point of thermostat.

Normal operation.

Adjust thermostat to

temp level

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 valve.

1. Page 14

2-4. Page 16

1. Pressure switch tubing kinked or blocked.

2. Blocked pressure tap on switch or blower.

3. Faulty pressure switch.

Page 17

1. Vent blockage or improper vent configuration.

2. Pressure switch tubing kinked or blocked.

3. Faulty pressure switch.

4. Blower not spinning up to speed.

5. Blower temp or exhaust temp too high

6. Faulty blower temperature switch.

7. Intake vent length exceeds exhaust vent length.

1. Check vent or vent tables.

2 & 3 Page 17

4. Page 21

5 & 6 Page 23

1. Thermal well sensor out of calibration.

2. Faulty gas control.

3. Plumbing leak

1. Page 25

2. Replace gas cont rol,
page 27

1. Pilot valve stuck in open position.

Replace gas control,
page 27

None, control LED not
on or flashing

No electrical
power

Control power switch in “OFF” position.
Supply voltage interrupted.

Turn power on

Page 12

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.

G

reen LED

Indicator

12

Six-four flash, three
second pause

Undesired-false
pilot flame
sensed.
System auto
resets.

Seven flash, three
second pause

Flammable Vapor
Sensor fault
detected

Eight-one flash, three
second pause

Flammable Vapor
Sensor out of
specification.

Thermal well
sensor damaged
or unplugged

Eight-three flash, three
second pause

Gas valve
electronics fault
detected

LED Status

Control

Status

Service

Procedure

Probable Cause

Pilot valve stuck in open position.

Replace gas control,
page 27

WARNING: EXPLOSION HAZARD

* Indicates gasoline vapors were detected at potentially

explosive levels.
* Verify no gasoline vapors are still present
* Reset the control by cycling power to the appliance or

by cycling the ON/OFF switch.
* Replace the Flammable Vapors Sensor element if a

gasoline spill event occurred.

Page 29

* Verify Flammable Vapor Sensor (FVS) resistance is

not below 25 K Ohms.
* Check wiring to FVS and insure it is not shorted.
* Replace control if everything above checks out OK.

Page 29

1. Damage to thermal well wire.

2. Thermal well sensor resistance out of range.

Page 25

1. Control needs to be reset.

2. Control is wet or physically damaged.

1. Interrupt power supply

2. Replace gas cont rol,
page 27

Eight-four flash, three
second pause

Gas valve fault
detected.

1. Control needs to be reset.

2. Control is wet or physically damaged.

1. Interrupt power supply

2. Replace gas cont rol,
page 27

T

roubleshooting

Six-three flash, three
second pause

Pilot flame
extinguished.
System auto
resets.

1. Unstable pilot.

2. Pilot tube blocked or restricted.

3. Oxidation build up on pilot electrode.

4. Wire damage to pilot assembly or bad
connection at gas valve.

5. Insufficient combustion air.

6. Gas pressure is out of specification.

1

. Page 14

2-4. Pag e 16

5. Refer to installation manual

Page 13

Six-two flash, three
second pause

Pressure switch
or blower temp
switch opened
during burner
operation.
System auto
resets.

1

. Check vent or vent tables.

2

& 3 Page 17

4

. Refer to venting section of

installation manual

5

. Page 21

6

& 7 Page 23

1. Vent blockage or improper vent configuration.

2. Pressure switch tubing kinked or blocked.

3. Faulty pressure switch.

4. Vent termination being affected by wind

5. Blower not spinning up to speed.

6. Blower temp or exhaust temp too high

7. Faulty blower temperature switch.

Six-one flash, three
second pause

Failed to light
pilot.
System auto
r

esets.

1. Unstable pilot.

2. Pilot tube blocked or restricted.

3. Oxidation build up on pilot electrode.

4

. Wire damage to pilot assembly or bad

connection at gas valve.

1. Page 14

2-4. Page 16

PDX Series

13

Step 1. With main burner in operation, remove outer jacket door remove inner door as described in this manual,

see inner door removal, inspection and replacement section (page 35).

Step 2. To adjust for proper burning, loosen the air shutter nut, rotate the air shutter to close the opening in the

burner, then slowly rotate the air shutter open until flame becomes as blue as possible with a minimum of
yellow tips. Tighten the air shutter nut.

Too much air will cause the flame to lift off the burner ports and create noisy burner operation.
Too little air will result in soot formation.

Step 3. Replace inner door as described in this manual, observe burner operation. Burner should operate as

adjusted in step 2. If not, repeat air shutter adjustment compensating for proper burner operation with inner
door closed.

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.

Pilot flame should be stable, some causes for an unstable pilot flame are:

a) Water heater vent is less than the allowable vent length.
b) Gas pressure is out of specification.
c) Pilot flame not fully engulfing spark/flame sensor.

Main burner should light smoothly from 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. Cast iron burner can
have the gas and air mixture properly proportioned by adjusting the air shutter on the mixer face of the main burner
(see cast iron burner adjustment below).

Main burner must be free from any debris accumulation that may effect burner operation (see burner cleaning
procedure on page 14).

Burner Inspection and Air Shutter Adjustment.

Cast Iron Burner Air Shutter Adjustment

WARNING

Inner door and burner components may be HOT when performing this operation. Take

necessary precaution to prevent personal injury.

Air Shutter Nut

PDX SERVICE PROCEDURE I

Burner Operation Inspection,

Adjustment, Cleaning and Replacement

Air Shutter

Page 14

PDX Series

14

Burner Cleaning

Step 1. Position gas control power switch to 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 inner door per service procedure XIII on page 35.

F

eedline nut

P

ilot tubing nut

Igniter/flame

sense wire

Step 4. Disconnect pilot tube (7/16 wrench) and

feedline (¾ wrench) from gas control.

Step 5. Disconnect igniter/flame sensor wire from gas control.

Step 6. Remove burner assembly from combustion chamber.

Step 7. Thoroughly inspect burner surface area and burner port area and

remove any loose debris.

Step 8. For cast iron burners, inspect for any debris build up inside

burner casting.

Burner

surface area

Burner

port area

Step 9. Unscrew burner from main burner

orifice. On cast iron burners, loosen
air shutter nut and unscrew feedline
from burner.

Step 10. Remove main burner orifice from

feedline (½" wrench on steel
burners, 3/8" wrench on cast iron)
inspect orifice, clean or replace if
necessary.

Step 11. Reassemble burner and reinstall into water heater. Restore gas supply

and check for gas leaks.

Step 12 To resume operation follow the instruction located on the lighting

instruction label or the lighting instruction located in the installation
and operating manual.

PDX SERVICE PROCEDURE I

Burner Operation Inspection,

Adjustment, Cleaning and Replacement

Page 15

L.P. Main burner
orifice. Left hand

thread

Main burner

orifice

PDX Series

15

PDX SERVICE PROCEDURE II

Pilot testing, Cleaning and Replacement

Pilot Inspection, Testing and Replacement

Step 1. Position gas control power switch to 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 inner door per service proceedure XIII on page 35.

Feedline nut

Pilot tubing nut

Igniter/flame

sense wire

Step 4. Disconnect pilot tube nut (7/16 wrench) and feedline nut

(¾ wrench) from gas control.

Step 5. Disconnect igniter/flame sense wire from gas control.

Step 6. Remove burner assembly from combustion chamber.

Step 7. Remove pilot assembly from feedline (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, check continuity

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" (.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 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.

Step 14. Reassemble pilot and install to feedline. Reinstall burner assembly to water heater. Restore gas supply

and check for gas leaks.

Step 15 To resume operation follow the instruction located on the lighting instruction label or the lighting

instruction located in the installation and operating manual.

Step 12. Visually inspect pilot tubing for kinks or cracks. If damage is

found replace pilot.

Ferrule

nut

Pilot

orifice

Pilot

hood

Igniter/flame

sense electrode

Igniter/flame

sense wire

Pilot

tubing

Page 16

PDX Series

16

PDX SERVICE PROCEDURE III

Pressure Switch Testing and

Replacement

Exhaust Pressure Switch
Testing

WARNING

120 volt potential exposure. Use caution

making voltage checks to avoid personal injury.

Step 1. Position power switch on gas control

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 1).

Step 3. Remove tubing and wires from inlet pressure switch.

Step 4. Carefully remove pressure switch from blower housing (see photo 2)

2

Use a multi-meter set to the

ohms setting. W ith 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 page 18)

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 & 4

complete,

disconnect wire leads from

pressure switch.

Y

N

Y

N

Switch contacts are OK.

See safety circuit trace

(page 30)

Is vent

system

blocked

N

See blower testing

(page 21)

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 page 7

Y

Reconfigure vent

system to be

compliant with

vent tables.

N

Y

Pressure switch

wire leads

Page 17

Check tubing and

pressure tap on

switch for blockage.

Is there blockage?

N

Y

PDX Series

1

E

xhaust

pressure switch

Inlet pressure

switch

17

Exhaust Pressure Switch
Replacement

WARNING

120 volt potential exposure. Use caution

to avoid personal injury.

Step 7. Reconnect wires from step 5 to new pressure switch.

Step 8. Reconnect tubing to new pressure switch.

Step 9. Carefully position pressure switch into blower housing.

Step 10. Reconnect wires and tubing to inlet pressure switch.

Step 11. Position gas control power switch to “ON” position and verify proper heater operation.

Step 12. Replace control access cover from step 2.

Step 1. Position gas control power switch

to “OFF” position.

Step 2. Remove the three screws (Phillips screw driver) from control access cover on blower assembly and

remove cover (see photo 3).

Step 3. Disconnect the tubing and wires from inlet pressure switch.

Pressure Switch

Slide pressure switch in direction
of arrow while tilting slightly away
from blower ho using.

Step 4. Carefully remove pressure

switch from blower
housing (see photo 4)

Step 5. Disconnect tubing from

pressure switch.
(see photo 5)

Step 6. Disconnect yellow wires

from pressure switch
(see photo 6)

PDX SERVICE PROCEDURE III

Pressure Switch Testing and

Replacement

Page 18

3

4

5 6

PDX Series

18

PDX SERVICE PROCEDURE III

Pressure Switch Testing and

Replacement

Inlet Pressure Switch
Testing

WARNING

120 volt potential exposure. Use caution

making voltage checks to avoid personal injury.

Step 1. Position power switch on gas control

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 7).

Step 3. Remove wires from inlet pressure switch.

Use a multi-meter set to the

ohms setting. W ith blower off,

check across pressure

switch terminals.

Are switch contacts closed?

Check tubing and pressure
tap on switch for blockage.

Is there blockage?

Replace switch

(see page 20)

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

remain closed with blower

running with the switch in

the vertical postition?

With steps 1,2 & 3

complete.

Y

N

Y

N

Switch contacts are OK.

See exhaust pressure

switch testing (page 17)

Is vent

system

blocked

N

See blower testing

(page 21)

Is blower OK?

Clear blockage

Y

N

Y

N

Correct blower

problem.

Is vent system length

within vent table

specifications

listed on page 7

Y

Reconfigure vent

system to be

compliant with

vent tables.

N

Y

Page 19

Check tubing and

pressure tap on

switch for blockage.

Is there blockage?

N

Y

PDX Series

7

Exhaust

pressure switch

Inlet pressure

switch

Inlet pr essure

switch wire
leads (found
inside cover)

19

Inlet Pressure Switch
Replacement

WARNING

120 volt potential exposure. Use caution

to avoid personal injury.

Step 7. Reconnect wires from step 5 to new pressure switch.

Step 8. Reconnect tubing to new pressure switch.

Step 9. Replace control access cover from step 2.

Step 10. Position gas control power switch to “ON” position and verify proper heater operation.

Step 1. Position gas control power switch

to “OFF” position.

Step 2. Remove the three screws (Phillips screw driver) from control access cover on blower assembly and

remove cover (see photo 8).

Step 3. Disconnect the tubing from the pressure switch (see photo 9).

Step 4. Remove inlet pressure

switch from blower access
cover. (see photo 10).

Step 5. Disconnect yellow wires

from pressure switch (see
photo 11).

Step 6. Attach new inlet pressure

switch to blower control
access cover.

PDX SERVICE PROCEDURE III

Pressure Switch Testing and

Replacement

Page 20

8 9

PDX Series

10

Remove screws

to remove inlet

pressure switch

11

20

PDX SERVICE PROCEDURE IV

Blower Testing and Replacement

WARNING

115 volt potential exposure. Use caution when

making voltage checks to avoid personal injury.

Blower Testing

Is there 115VAC
across terminals

shown in photo 17 ?

Incorrect supply

voltage polarity

Determine

power source

problem and

correct.

D

oes blower energize

Within 2 minutes?

Y

Disconnect cord set

shown in photo 9. Is

there 115VAC across

terminals shown in

photo 16

N

See pressure
switch testing
Page 17 & 19

Is there 115 VAC

at wall outlet?

Check power cord

for damage.

Y

N

D

isconnect

p

ressure switch

tubing from blower.

(

see pho to 13)

Connect

manometer to

p

ressure tap of

blower.

(see photo 13)

With blower running, and exhaust

adapter removed from top of

blower, is there a negative

pressure of -2.30" to -2.60" W.C.?

Step 1. Position gas control power switch

to “ON” position and adjust control to call for heat.

Step 2. Remove the three screws (Phillips Screw driver)

from control access cover on blower assembly and
remove cover (see photo 12).

Reconnect cord set

shown in photo 9, is

there 115VAC between

blue wire and green

ground wire

(see photo 18)

Replace blower

Does cord set

have e lectrical

continuity?

Disconnect vent

s

ystem from top of

b

lower and remo ve

exhaust vent

a

dapter.

(see photo 15)

Does blower energize after

2 minutes, run for 30

seconds and shut down?

N

Is there 115vac across

blue and green wires

(see photo 18)

Blower OK

Y

Repair or replace

power cord

Replace blower

Y

N

N

N

N

Y

Y

Y

Y

N

Pressure

switch tubing

Pressure tap

Remove exhaust

adapter

Shown with pressure

switch removed.

Green ground

wire

Blue w ire

Replace blower

Y

Determine voltage

problem and correct.

N

Page 21

1

2

13

14

16 17

18

15

Replace

gas control

Y

Replace
cord set

N

PDX Series

21

PDX SERVICE PROCEDURE IV

Blower Testing and Replacement

Step 1. Position gas control power switch to the “OFF” position.

Step 2. Unplug blower power cord from wall outlet.

Step 3. Disconnect vent system from exhaust adapter on top of

blower.

Step 4. Remove exhaust adapter from blower (blade screw driver)

and retain for use on new blower

Step 5. Unplug cord sets from blower.

Step 6. Remove vertical air intake bracket.

Step 7. Disconnect vertical air intake from blower.

Step 8. Remove the three blower mounting screws

(¼" nut driver).

Step 9. Remove blower with gasket from water heater.

Blower Mounting

Screws

Blower

C

ord Sets

Step 10. Clean any debris from jacket head of water heater.

Step 11. Set new blower with gasket in place using locating pins on

blower flange to line up with location holes in jacket head.
Be sure not to damage gasket.

Step 12. Secure blower in place using mounting screws from step 8.

Step 13. Slide vertical air intake tee onto blower.

Step 14. Re-install vertical air intake bracket.

Step 15. Re-install exhaust adapter from step 4.

Step 16. Reconnect vent system to exhaust adapter.

Step 17. Reconnect cord sets from step 5.

Step 18. Plug blower power cord into wall outlet.

Step 19. Position gas control power switch to the “ON” position.

Step 20. Verify proper blower operation.

Locating Pins

on blower flange

Pin location holes in

jacket head

R

emove exhaust

a

dapter and retain for
u

se on new blower.

Blower removal

Blower Installation

Page 22

PDX Series

Vertical air intake

bracket

Vertical air intake

22

PDX SERVICE PROCEDURE V

Blower Temperature Switch Testing

and Replacement

Blower Temperature Switch
Testing.

WARNING

120 volt potential exposure. Use caution

to avoid personal injury.

1

9

Disconnect wire leads to

switch. Using a multi-meter

set to the ohms setting, is

there continuity between

the switch terminals?

Switch OK

Cool switch to

below 130°F

N

Y

Switch Setting

O

pens on rise @ approximately 165°F

Auto resets on fall @ approximately 130°F

Step 1. Position power switch on gas control

to the “OFF” position.

Step 2. Remove tubing from inlet pressure tap.

Step 3. Remove the three screws (Phillips screw driver) from

control access cover on blower and remove cover (see
photo 19).

Step 4. Locate blower temperature switch (see photo 19)

Reconnect wire leads and

observe heater operation.

Do exhaust gas

temperatures r ise to or

above 165° F?

Replace switch

(see page 24)

Y

N

Do switch

contacts open?

Do switch

contacts open?

N

Y

Replace switch

(see page 23)

N

Y

Exhaust

temperature is

too hot.

Common causes for

high exhaust temperature

1. Vent length is below minimum allowable.

2. Vent diameter not to specification.

3. Restricted dilution air inlet.

4. Missing or deteriorated flue baffle.

5. Gas pressure is out of specification.

Blower temperature

switch location

20

Air mixing inlet

Page 23

PDX Series

23

PDX SERVICE PROCEDURE V

Blower Temperature Switch Testing

and Replacement

Blower Temperature Switch
Replacement.

WARNING

120 volt potential exposure. Use caution

to avoid personal injury.

Step 1. Position gas control power switch to the “OFF” position

and unplug heater from wall outlet.

Step 2. Remove tubing from inlet pressure tap.

Step 3. Remove the three screws (Phillips screw driver) from the

control access cover on blower and remove cover.
(see photo 20)

2

0

Step 4. Locate blower temperature switch (see photo 21)

Step 5. Disconnect red and yellow wire leads from switch.

Step 6. With an appropriate tool such as side cutters, snip the

retaining lug from the blower housing to allow removal of
temperature switch (see photo 22).

Step 7. Remove switch from blower housing.

Step 8. Install new switch. Be sure switch is properly seated in

mounting area.

Step 9. Reconnect red and yellows wires to new switch. Wires are

interchangeable with either terminal.

Step 10. Position gas control power switch to the “ON” position

and verify proper heater operation.

Step 11. Replace control access cover from step 2.

Blower temperature

switch location

21

Snip retaining lug

from blower housing

22

Page 24

PDX Series

24

PDX SERVICE PROCEDURE VI

Gas Control/Thermal Well Testing and

Replacement

PDX Series

Thermal Well Testing

Thermal well testing

Position gas control power switch to

the “OFF” position and disconnect

thermal well harness from gas

control.

N

Y

Using a multi-meter set to the ohms setting, insert one meter probe (see caution)
into center wire position of thermal well connector, insert the second probe (see
caution) into either of the outside wire positions (see photo 23).

Alternate the probe on the outside position to the opposite outside wire position
(see photo 24).

Replace thermal well

(see page 27)

Using a multi-meter set to the

Ohms setting, determine the

resistance of thermal well sensor

(see caution photos 23 & 24)

Disconnect thermal

well wire harness

19

20

Replace gas control

(see page 27)

Page 25

Gas Control Testing

See pages 27 & 28 for gas control
input & output testing.

Once the thermal well resistance values are known, the water

temperature must also be known to determine if the resistance

values are correct. See page 25 to obtain water temperature.

Are thermal well resistance values correct?

CAUTION

DO NOT use standard multimeter probes for this test.
Doing so will damage connector. Use special pin type
electronic probes or small diameter wire pins inserted
into connector.

If Control has gone into TCO lockout due to

excessive tank temperature (four flash, 3 second
pause) reset control by rotating knob of temperature
control to the minimum setting for at least 6 seconds

before returning to desired temperature setting.

Observe heater operation. If control

continues to lockout due to

excessive tank temperature,

proceed to thermal well testing to

determine cause.

25

°F012345678 9
40 26109 25400 24712 24045 23399 22771 22163 21573 21000 20445
50 19906 19383 18876 18383 17905 17440 16990 16553 16128 15715
60 15314 14925 14548 14180 13823 13477 13140 12812 12494 12185
70 11884 11592 11308 11032 10763 10502 10248 1000 9760 9526
80 9299 9078 8862 8653 8449 8250 8057 7869 7685 7507
90 7333 7165 7000 6839 6683 6531 6383 6238 6098 5961

100 5827 5697 5570 5446 5326 5208 5094 4982 4873 4767
110 4663 4562 4464 4368 4274 4183 4094 4006 3922 3839
120 3758 3679 3602 3527 3453 3382 3312 3244 3177 3112
130 3048 2986 2925 2866 2808 2752 2697 2643 2590 2538
140 2488 2439 2391 2344 2298 2253 2209 2166 2124 2083
150 2043 2004 1966 1928 1891 1856 1820 1786 1753 1720
160 1688 1656 1625 1595 1566 1537 1509 1481 1454 1427
170 1402 1376 1351 1327 1303 1280 1257 1235 1213 1191
180 1170 1150 1129 1110 1090 1071 1953 1035 1017 999
190 982 965 949 933 917 901 886 871 857 842
200 828 814 801 788 775 762 749 737 725 713

In Degrees F

Sensor Resistance at Various Temperatures

Example: If temperature of water is 84°F, then the resistance through the sensor would be

8449 (see shaded area). NOTE: Sensor resistance increases as the temperature
falls.

WARNING

Stored water may be HOT when performing the following steps in this procedure.

Take necessary precaution to prevent personal injury.

PDX SERVICE PROCEDURE VI

Gas Control/Thermal Well Testing and

Replacement

Determine Water Temperature Inside Tank

Step 1. Position gas control power switch to “OFF” position.

Step 2. Draw approximately 4 gallons of water from drain valve into a container and discard. Draw an

additional gallon and immediately measure water temperature using an accurate thermometer. It may
be necessary to open a hot water faucet to allow heater to drain.

Step 3. Using the chart below, determine correct resistance value for the water temperature from step 2.

Note: It is important to understand once the resistance for the thermal well is determined from page 25, water flow
through the heater should not occur. Prior to performing the steps below, turn off the cold water supply to the
water heater. This will prevent cold water flow into the tank affecting the resistance value of thermal well.

Page 26

PDX Series

26

PDX SERVICE PROCEDURE VI

Gas Control & Thermal Well Testing

and Replacement

Gas Control & Thermal Well Removal From Water Heater

Step 1. Position gas valve power switch to the “OFF”

position and Unplug Heater from power supply.

Step 2. Drain heater to a point below the gas

control level.

Step 3. Turn off gas supply to water heater and

disconnect gas piping from gas control.

Step 4. Disconnect wire harnesses and burner assembly

from gas control.

Step 5. Remove gas control & thermal well by rotating flats of Thermal Well counter clockwise (1-5/16"wrench).

Gas Control

Thermal
Well

Page 27

Gas Control Removal From Thermal Well

Step 1. Position gas control power switch to the “OFF” position and unplug water heater from power supply.

Step 2. Turn off gas supply to water heater and disconnect gas piping from gas control.

Step 3. Disconnect wire harnesses & burner assembly from gas control.

Step 4. Using gas control service tool (239-45991-00) available from your BWC parts supplier, Insert tool into

back of gas control (see photos below)

Follow the steps below allows removal gas control from thermal well without
removing thermal well from tank.

Step 5. Pivot tool towards heater as far as possible (see photo below). Lift straight up on gas control. The

control should move about 1/8". Hold control in position and remove tool. Lift straight up on control to
remove completely from Thermal Well.

Service tool shown

inserted in to back

of control

Insert tool from
back of control

View from back of

control for clarity

With service tool inserted, pivot tool back towards water

heater as far as possible. Lift straight up on control,

control will move 1/8". Remove tool and continue to lift

straight up on control to remove from Thermal Well.

PDX Series

27

Gas Control Assembly to Thermal Well

Step 6. Reconnect wire harnesses to gas control

per the illustration.

Step 7. Reconnect gas piping to gas control.

Restore gas supply and check for gas
leaks.

Step 8. To resume operation, follow the

instruction located on the lighting
instruction label or the lighting instruction
located in the installation and operation
manual.

5 pin

blower harness connection

3 pin
thermal well connection

Ground Wire

connection

Igniter/sensor

connection

Thermal well
flange slots

Gas control Tabs

PDX SERVICE PROCEDURE VI

Gas Control & Thermal Well Testing

and Replacement

Page 28

24

2

5

Step 1. Install threaded end of thermal well into tank. Be sure

thermal well flange is positioned as shown in photo 24
for proper control alignment.

Step 2. Route wire leads back into relief opening.

(see photo 24)

Step 3. Align slots located on thermal well flange with tabs

located on back of gas control (see photo 24 & 25)

Step 4. Carefully push control back onto thermal well flange

as far as possible towards water heater. Slide control
down to lock into position.

Step 5. Install burner and connect pilot tubing and feedline nut

to gas control.

Route wires
through relief
opening

PDX Series

Flammable Vapor
Sensor

28

PDX SERVICE PROCEDURE VII

Flammable Vapors Sensor Testing

Page 29

PDX Series

Flammable Vapor
Sensor

Step 1. Position power switch on gas control to the

“OFF” position.

Step 2. Disconnect flammable vapor sensor from

gas control.

Step 3. Using a multi-meter set to the ohms setting

check resistance of flammable vapor sensor.
(see caution below)
Resistance must be within 3,000 ohms and
48,000 ohms. If outside of this range replace
flammable vapor sensor.

Flammable Vapor Device Testing

Flammable Vapor
Sensor

Electronic
“pin type”
Meter Probes

Multi-meter set to
ohms setting

CAUTION

DO NOT use standard multimeter probes for this test.

Doing so will damage connector. Use special electronic

“pin type” probes or small diameter wire pins inserted

into connector.

29

PDX SERVICE PROCEDURE VIII

Safety Circuit Voltage Trace

Safety Circuit Voltage
Trace

WARNING

120 volt potential exposure. Use caution

making voltage checks to avoid personal injury.

Position gas control switch to the “ON”

position and adjust thermost at dial to call

f

or heat, Is there 10 to 13 VAC between

red wire leading to blower temperature

switch and green ground wire?

Blower must be running during this

voltage check.
(see photo 28)

Red wire leading to

blower temp. switch

Green ground wire

28

Yellow wire

leading from

pressure switch

Y

Is there 10 to 13 VAC betwee n yellow

wire leading from pressure switch and

green ground wire?

(see photo 28)

Do you hear or can you

see the igniter sparking?

Y

Y

Is LED on gas valve flashing

t

he “heartbeat” code

(alternating bright/dim)

N

Safety circuit

voltage is OK.

N

o voltage from gas control,
call for technical support.

Y

NOTE: This procedure assumes a cool tank.

Verify 120VAC to gas
control (see page 30)

Is there continuity

through blower

temperature switch?

(see page 21)

Y

Check for loose or

broken wire

connection at switch

terminals

N

N

Determine cause of blower

temperature switch

activation and correct.

Check igniter/sensor

(see page 16)

is igniter/sensor OK?

If burner does not light,

observe LED flash code

on gas valve and refer to

troubleshooting section

on page 12

N

N

Page 30

2

7

Step 2. Remove three screws (Phillips Screw driver) from control

access cover on blower and remove cover (see photo 26).

Faulty cord set or

gas control.

Y

Correct igniter/

sensor problem.

PDX Series

30

PDX SERVICE PROCEDURE IX

120 VAC Trace

WARNING

120 volt potential exposure. Use caution

making voltage checks to avoid personal injury.

Disconnect cord set as

shown in photo 29

L

ED status

N

one, Control LED not

on or flashing.

Step 1. Verify 120VAC and proper polarity at wall outlet.

Step 2. With unit plugged in and control power switch in the “ON” position verify LED status.

L

ED status

S

hort flash, once every

four seconds.

L

ED status

“

Heartbeat”, alternates

bright/dim.

L

ED status

V

arious flashing error

codes.

Waiting for

call for heat.

Thermostat calling

for heat

Verify error code as

listed on page 12

Using a volt meter set

to volts AC, is there

120VAC across

terminals shown in

photo 30 ?

N

Y

29

3

0

Reconnect cord set

shown in photo 29.

Repair damage

Check for damage to

AC supply power cord.

Y

N

Replace Blower

33

Check for 120VAC between black & white wires.

-NOTE-

Electronic meter probes required. Use care not to

damage connector during this check.

Wire sheath pulled back to

identify wire colors

32

Wire harness

Disconnect wire harness

from gas control

(see photo 32).

Locate black & white wires at

connector, It may be necessary to pull

back wire sheath to identify wire colors.

(see photo 33)

Y

N

Replace gas

control.

Is there 120VAC

across black & white

wires as shown in

photo 33?

Call for technical

support.

Is there 120VAC

across terminals

shown in photo 31 ?

N

Y

Incorrect supply

voltage polarity

3

1

Page 31

120 VAC Circuit Trace

PDX Series

31

PDX SERVICE PROCEDURE X

Dip Tube

Inspection and replacement

Step 1. Position on/off switch of gas control valve to “OFF” position and unplug water heater from wall outlet.

Step 2. Turn off cold water supply to water heater. Connect hose to drain valve of water heater and route to an

open drain. Open a nearby hot water faucet to vent heater for draining. Open drain valve of water
heater and allow heater to drain to a point below the inlet connection nipple.

Step 3. Disconnect inlet nipple from plumbing system.

Step 4 With an appropriate tool such as a pipe wrench, remove inlet nipple/dip tube from the water heater.

Use caution not to damage pipe threads.

Step 5. Visually inspect inlet nipple/dip tube. Inlet nipple/dip tube should be free of cracks and any blockage.

Hydro-jet slots should be open and free of any blockage.

Any damage such as cracks, restriction due to deformation or unintentional holes are not field
repairable and the inlet nipple/dip tube must be replaced.

Step 6. Upon completion of inspection or subsequent replacement, reinstall inlet nipple/dip tube into water

heater. Connect nipple to plumbing system, resume water supply and refill with water.

Step 7. To resume operation follow the instructions located on the lighting instruction label or the lighting

instructions located in the installation and operation manual.

Dip Tube Inspection and Replacement

WARNING

Water Heater components and stored water may be HOT when performing the following

steps in this procedure. Take necessary precaution to prevent personal injury.

Page 32

PDX Series

32

PDX SERVICE PROCEDURE XI

Anode

Inspection and replacement

Step 1. Position on/off switch of gas control valve to the “OFF” position and unplug water heater from wall

outlet.

Step 2. Turn off cold water supply to water heater. Connect hose to drain valve of water heater and route to an

open drain. Open a nearby hot water faucet to vent water heater for draining. Open drain valve of
water heater and allow water heater to drain to a point below the outlet connection nipple.

Step 3. Disconnect outlet nipple from plumbing system.

Step 4 With an appropriate tool such as a pipe wrench, remove outlet nipple/anode from the water heater. Use

caution not to damage pipe threads.

Step 5. Visually inspect outlet nipple/anode. Outlet nipple/anode should show signs of depletion, this is

normal. If depletion is ½ of the original anode diameter (approximately ¾” diameter), replacement is
recommended. If any of the steel core of the anode is exposed, replacement is recommended.

Step 6. Upon completion of inspection or subsequent replacement, reinstall outlet nipple/anode into water

heater. Connect nipple to plumbing system, resume water supply and refill with water.

Step 7. To resume operation, follow the instructions located on the lighting instruction label or the lighting

instructions located in the installation and operation manual.

Anode Inspection and Replacement

WARNING

Water Heater components and stored water may be HOT when performing the following

steps in this procedure. Take necessary precaution to prevent personal injury.

Page 33

PDX Series

33

PDX SERVICE PROCEDURE XII

Flue Baffle

Inspection and replacement

Step 1. Position gas control power switch to the “OFF” position and

unplug blower from wall outlet.

Step 2. Disconnect vent system from exhaust adapter on top of blower.

Step 3. Disconnect intake air piping.

Step 4. Unplug cord sets from blower. (see photo 34).

Step 5. Remove the three blower mounting screws

(¼" nut driver) (see photo 34).

Step 6. Remove blower with gasket from water heater.

Step 7. Remove flue baffle from Heater (see photo 36).

Step 8. Inspect baffle for deterioration, missing restrictors.

Clean any scale or debris build up. Replace with new baffle as
necessary.

Step 9. Reinstall baffle into flue tube. Be sure baffle

hanger tabs are inserted into notch location at the
top of the flue tube (see photos 36 & 37).

Step 10. Check Burner to insure no scale has accumulated during this

operation. See burner cleaning procedure on page 15.

Step 11. Reinstall blower on water heater. Connect vent

system and cords set to blower. Plug water heater
into wall outlet.

Step 12. To resume operation follow the lighting instruction

located on the lighting instruction label or the lighting instruction
located in the installation and operation
manual.

B

lower Mounting

S

crews

B

lower

Cord Sets

3

4

Disconnect vent

s

ystem from exhaust

a

dapter.

Remove blower to gain access to
flue baffle

Flue Baffle

Flue tube

notch

Baffle shown

installed in flue

tube notch.

Page 34

36

37 38

PDX Series

35

Remove support

bracket

34

PDX Series

Step 4. Right side Inner Door Removal.

a) Remove wire tie from feedline.
b) Remove (2) 1/4" hex drive screws from right side inner door.
c) Remove (2) 1/4" hex drive screws from flange section of inner door.
d) Remove right side inner door and set aside. Be careful not to damage gasket material on inner door.

¼" Hex Drive Screws shown on
Right Side Inner Door.

Inner Door Removal Procedure.

Step 1. Slide switch of the Electronic Gas Control to the “OFF” position and unplug from wall.

Step 2. Remove outer jacket burner access door.

Step 3. Disconnect wire connections from Electronic Gas Control.

Step 4. Fully inspect inner door gaskets for the following:

>Tears >Other imperfection that will inhibit proper seal
>Missing Material >Gasket adhesion to inner door
>Cracks >Material left on combustion chamber (around opening)
>Dirt or debris

If the gasket is not effected by any of the above, gasket replacement is not required. If replacement is required,
proceed to Inner Door Gasket Replacement Procedure.

Inner Door Gasket Replacement Procedure.

WARNING

If the information in these instructions is not

followed exactly, a fire or explosion may result causing

property damage, personal injury or death.

Step 5. After inspection of inner door as noted in step 4, completely remove gasket and adhesive residue from right

and left side inner doors as needed.

Step 6. Use RTV sealant (recommended bead size is 1/8") to secure the inner door gasket to the inner door sections

(right & left). Refer to illustration below for proper application. Note the overlap configuration in the flange
area of the inner door. Set the flange section first, this will help to achieve the proper over lap position.

¼" Hex Drive Screws at

Flange section of Inner Door

PDX SERVICE PROCEDURE XIII

Inner Door/Gasket Removal, Inspection

Replacement and Reinstallation

Page 35

35

PDX Series

Installation of Inner Door With Gasket.

WARNING

Stripped fastener connections may allow

for seal breach of inner door. A seal

breach may result in a fire or explosion

causing property damage, personal

injury or death. Do not over tighten

screws in steps 8, 10 and 11.

If a fastener connection is stripped,

contact the manufacturer listed on the

water heater rating plate.

Step 7. Clean any residual gasket residue or other debris

from combustion chamber surface before installing
the inner door/gasket assembly.

Step 8. Place the left side inner door into position first.

Firmly position the radiused channel of the inner
door around the feedline. Using the 1/4” hex drive
screws from step 3d, secure left side inner door in
place. DO NOT OVER TIGHTEN SCREWS.

Step 9 Position thermocouple, pilot tube and Piezo wire

against left side inner door flange gasket. DO

NOT ROUTE THROUGH RADIUSED
CHANNEL WITH FEEDLINE.

Radiused Channel

for Feedline

PDX SERVICE PROCEDURE XIII

Inner Door/Gasket Removal, Inspection

Replacement and Reinstallation

Igniter wire and pilot tube

shown in proper position.

Page 36

36

PDX Series

Step 10. Firmly place right side inner door flange against the left side inner door flange and secure with two ¼” drive

screws from step 3c. DO NOT OVER TIGHTEN SCREWS.

Step 11. Align right side inner door to combustion chamber and verify the fastener holes of the combustion

chamber are aligned with the right side inner door slotted opening. Verify seal integrity around combustion
opening. Secure right side inner door using 1/4” hex drive screws from step 3b. DO NOT OVER TIGHTEN
SCREWS. Verify both left and right sides of the inner door are properly positioned and sealed against the
combustion chamber

Step 12. Replace outer jacket burner access door.

Step 13. To resume operation follow the instructions located on the lighting instruction label or the lighting instructions

located in the installation and operation manual.

PDX SERVICE PROCEDURE XIII

Inner Door/Gasket Removal, Inspection

Replacement and Reinstallation

Verify threaded hole

alignment with slotted

openings in inner door.

Page 37

Installation of inner door with gasket (continued from page 36).

37

NOTES

Page 38

Glossary of Terms

BTU British Thermal Units
GPM Gallons per Minute
Hz Hertz
KW/h Killo-watts per hour
LED Light Emitting Diode
NPT National Pipe Thread
Ohms Ohms of resistance
PSI Pounds per Square Inch
RPM Revolutions per Minute
TCO Temperature Cut Off
VAC Volts Alternating Current
W.C. Inches of Water Column
°C Degrees Centigrade
°F Degrees Fahrenheit

PDX Series

38

Parts List

1. Blower Assembly

2. Blower Temp. Switch

3. Exhaust Pressure Switch

4. Inlet Pressure Switch

5. Blower Gasket

6. Tee and Vent Pipe Assy.

7. Vent Adapter with Term.

8. Intake Terminal

9. Vent Terminal Elbow

10. Exhaust Adapter

11. Condensate Hose Kit

12. Flue Reducer

13. Heat Trap Insert (outlet)

14. Heat Trap Insert (inlet)

15. Hot Water Outlet Anode

16. Cold Water Inlet Diptube

17. Flue Baffle

18. Blower Harness

19. T&P Relief Valve

20. ¾ NPT PLUg

21. Direct Vent Boot
Escutcheon

22. Air Intake Boot

23. Air Intake Boot Gasket

24. Outer Door

25. Right Side Inner Door

26. Left Side Inner Door

27. Screw-#10-12 x ¾ HWH

28. Screw-#8-18 x ¾ HWH

29. Brass Drain Valve

30. Flammable Vapor Sensor

31. Sensor Harness

32. Flammable Vapor Sensor
Clip

33. Thermal Well

34. Gas Control Kit

35. Gas Control Service tool

36. Gas Control

37. Gas Burner Assy (Nat.)

38. Gas BN burner (Nat.)

39. Main Burner Orifice (Nat.)

40. Gas Pilot Assembly (Nat.)

Page 39

PDX Series

41. Gas Pilot Orifice (Nat.)

42. Gas Feedline (Nat.)

43. Gas Burner Assy (L.P.)

44. Cast Iron Burner (L.P.)

45. Gas Pilot Assy (L.P.)

46. Gas Pilot Orifice (L.P.)

47. Air Shutter (L.P.)

48. LP Gas Feedline (L.P.)

49. Air Shutter Nut (L.P.)

50. Main Burner Orifice (L.P.)

51. Inner Door Gasket

52. Heat Trap Insert kit

53. Mixing Valve

39

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