31
TROUBLESHOOTING CHART
PCBBF145 CONTROL BOARD
Symptoms of
Abnormal Operation
Associated
LED Code
2
Fault Description(s)
Possible Causes
Corrective Action
Cautions
and Notes
• Circulating blowers not
operating
simultaneously.
No blower operation.
9 FLASHES
• Twinning Fault
• Furnace twin terminals not
connected together by field
wiring.
• Isolating relay not used or
improperly installed.
• Install field wiring connecting twin
terminals, check continuity of
wiring.
• Verify each furnace fan motor is
operable without twinning
connection.
• Wire per twinning diagram in this
installation manual.
• Verify line voltage
supply is turned off
before proceeding
with corrections.
• Furnace not operating.
• Integrated control
module diagnostic
LED
is flashing
TEN
(10)
flashes.
10 FLASHES
• Open Fuse / No 24V
power to integrated
control module
• High voltage surge blows off
the fuse.
• Replace the Fuse.
• Verify line voltage
supply is turned off
before proceeding
with corrections.
• Furnace not operating.
• Integrated control
module diagnostic
LED
is flashing
ELEVEN
(11) flashes.
11 FLASHES
• Igniter Open
• Improperly connected igniter.
• Bad igniter.
• Poor unit ground.
• Poor burner ground.
• Check and correct wiring from
integrated control module to
igniter.
• Replace bad igniter.
• Check & correct unit ground wire.
• Replace bad integrated control
module.
• Turn power OFF
prior
to repair.
• Replace igniter
w/proper
replacement part.
• Read precautions in
“Electrostatic
Discharge"
• Furnace not operating.
• Integrated control
module diagnostic
LED
is flashing
TWELVE
(12) flashes.
12 FLASHES
• Inducer Relay Fault
• Improper Grounding
• Improperly connected
inducer.
• Bad inducer.
• Poor unit ground.
• Faulty integrated control
module.
• Check and correct wiring from
integrated control module to
inducer.
• Check for Blockage in inducer &
in
Vent / replace Inducer.
• Check & correct unit ground wire.
• Replace bad integrated control
module.
• Turn power OFF
prior to repair.
• Replace inducer
w/proper
replacement
part.
• Read precautions in
“Electrostatic
Discharge"
section of manual.
• Furnace fails to
operate.
• Integrated control
module diagnostic
LED
is flashing
continuously.
CONTINOUS
RAPID FLASH
• Polarity of 115 or 24
volt power is reversed
• Polarity of 115 volt AC power
to
furnace or integrated control
module is reversed.
• Orange and gray wires to
transformer are reversed.
• Poor unit ground.
• Review wiring diagram to correct
polarity.
• Reverse orange and gray wires
going to transformer.
• Verify proper ground. Correct if
necessary.
• Turn power OFF
prior to repair.
9
10
11
12
C
1
Integrated control module will automatically attempt to reset from lockout after one hour.
2
LED Flash code will cease if power to the control module is interrupted through the disconnect or door switch.