Installation Guide

29
T ROUBLESHOOTING C HART
PCBBF145 CONTROL BOARDS
2
LED Flash code will cease if power to the control module is interrupted through the disconnect or door switch.
Associated
LED Code
2
•Induced draft blower runs
continuously. No furnace
operation.
•Integrated control module
diagnostic LED is flashing
continuously.
C
CONTINUOUS
•Polarity of 115
or 24 volt
power is
reversed.
•Polarity of 115 volt AC
power to furnace or
integrated control module
is reversed.
•Red and blue wires to
transformer are reversed.
•Poor unit ground.
•Review wiring diagram to
correct polarity.
•Verify proper ground.
Correct if necessary.
•Reverse red and blue wires
connected to transformer.
•Turn power OFF
prior to repair.
• Normal operation.
•LED is steady on
STEADY
•Furnace not operating.
•Integrated control
module diagnostic LED is
flashing EIGHT (8) flashes.
8 FLASHES
•Problem with
igniter circuit.
•Improperly connected
igniter.
•Bad igniter.
•Poor unit ground.
•Poor burner ground.
•Faulty integrated control
module.
•Check and correct wiring
from integrated control
module to igniter.
• Compare igniter
resistance to spec.
Replace if necessary.
• Check and correct unit
ground wiring.
•Replace bad integrated
control module.
•Turn power OFF
prior to repair.
•Replace igniter
with proper
replacement part.
•Read precautions
in “Electrostatic
Discharge” section
of manual.
Cautions
& Notes
Corrective Action
Possible Causes
Fault
Description(s)
Symptoms of
Abnormal Operation
FLASHING
Associated
LED Code
2