Bradford White U-4-XRTW65T6FRN User Manual

SUPPLEMENT TO INSTRUCTION MANUAL

P/N 238-45637-00 and 238-48933-00

(Replaces pg. 32 (238-45637-00) or pg. 28 (238-48933-00) in

instruction manual.)

Wiring Diagram

Honeywell

VERY

HO

C

B

A

HO

LOW

Figure 10 or Figure 6

238-48214-00B REV 11/09

Burner Flame Check

(Replaces pg. 36 (238-45637-00) or pg. 32 (238-48933-00) in

instruction manual.)

These models are equipped with self adjusting air mixture and do not have an
adjustable air shutter (See Figure 12). At periodic intervals a visual check of
the main burner and pilot flames should be made to determine if they are
burning properly. The main burner flame should light smoothly from the pilot.

Figure 12 or Figure 8

2

(Replaces pg. 42 (238-45637-00) or pg. 38 (238-48933-00) in

instruction manual.)

Troubleshooting continued-

LED Status Control Status Proba b le Cause

Six flashes-three
flashes, three second
pause (Soft lockout)

Six flashes-four
flashes, three second
pause

Seven flashes, three
second pause

Eight flashes-one flash,
three second pause

Eight flashes-three
flashes, three second
pause

Eight flashes-four
flashes, three second
pause

Pilot flame
extinguished.
System re s et s afte r 5
minutes.

Undesired-false pilot
flame sensed.
System auto resets.

Flammable vapor
sensor fault detected,
see warning label

Flammable vapor
sensor out of
specification. Possible
short.

T'stat well & sensor
damaged or unplugged

or
Gas valve electronics
fault detected

Gas valve fault
detected.

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.

Pilot valve stuck in open position.

1. Flammable vapor present

2. Flammable vapor sensor exposed to excessive
moisture

3. Flammable vapor sensor exposed to extreme
ambient temp

4. Resettable thermal switch open.

1. Flammable vapor sensor out of specification

2. Possible short in flammable vapor sensor or
resettable thermal switch wiring.

1. Damage to thermowell wire.

2. Thermowell sensor resistance out of range.

3. Replace thermowell.

4. Verify control is not wet or physically damaged

5. Reset control on/off switch.

6. Replace electronic module if 8-3 error persists

1. Verify control is not wet or physically damaged

2. Reset control on/off switch.

3. Replace gas control if 8-4 error persists

Fault Probable Cause

Resettable thermal switch tripped
(open)

Control Sequence of Operation

1. Burner failure.

2. Flammable vapor present.

Start up Sequence

Upon powering up, the control checks for the presence of the vapor sensor, if
the resistance is in the expected range the control will begin normal operation
after 5 to 8 seconds.
Normal Heating Sequence

1. The thermostat senses a need for heat.

2. The control checks the pressure switch condition.

3