Goodman MH8 Installation Instructions Manual page 39

T
ROUBLESHOOTING
Symptoms of
Abnormal Operation
• Furnace not operating.
• Integrated control module
diagnostic LED is
flashing EIGHT (8)
flashes.
• Induced draft blower runs
continuously. No furnace
operation.
• Integrated control module
diagnostic LED is flashing
continuously.
• LED is steady on
2 LED Flash code will cease if power to the control module is interrupted through the disconnect or door switch.
C
HART
Fault
Associated
Associated
Description(s)
LED Code 2
LED Code 2
• Problem with
igniter circuit.
8 FLASHES
• Polarity of 115
or 24 volt
C
power is
reversed.
CONTINUOUS
FLASHING
• Normal operation.
STEADY
Possible Causes
• Improperly connected
igniter.
• Bad igniter.
• Poor unit ground.
• Poor burner ground.
• Faulty integrated control
module.
• 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.
39
Corrective Action
• Check and correct wiring
from integrated control
module to igniter.
• Replace bad igniter.
• Check and correct unit
ground wiring.
• Replace bad integrated
control module.
• Review wiring diagram to
correct polarity.
• Verify proper ground.
Correct if necessary.
• Reverse red and blue
wires connected to
transformer.
Cautions
& Notes
• Turn power OFF
prior to repair.
• Replace igniter
with proper
replacement part.
• Read precautions
in "Electrostatic
Discharge"
section of manual.
• Turn power OFF
prior to repair.