Troubleshooting Chart - Goodman GMV95 Installation Instructions Manual

Symptoms of Abnormal
Operation
• Furnace fails to operate.
• Integrated control
module diagnostic LED
provides no signal.
• Normal Steady On
• Furnace fails to operate.
• Integrated control
module diagnostic LED
is flashing ONE (1) flash.
• Furnace fails to operate.
• Integrated control
module diagnostic LED
is flashing TWO (2)
flashes.
• Induced draft blower runs
continuously with no
further furnace operation.
• Integrated control
module diagnostic LED
is flashing THREE (3)
flashes.
1
Integrated control module will automatically attempt to reset from lockout after one hour.

TROUBLESHOOTING CHART

Associated
Fault Description(s)
LED Code 2
NONE • No 115 volt power to
furnace, or no 24 volt
power to integrated
control module.
• Blown fuse or circuit
breaker.
• Integrated control
module has an
internal fault.
• Normal Operation
ON
CONTINUOUS
ON
• Furnace lockout due
1 to an excessive
number of ignition
1
"retries" (3 total)
1 FLASH
and "recycles
infinite".
• Pressure switch
2 circuit is closed.
• Induced draft
blower is not
2 FLASHES
operating.
• Pressure switch
circuit not closed.
3
• Induced draft blower
is operating.
3 FLASHES
Possible Causes
• Assure 115 and 24 volt
• Manual disconnect switch
OFF, door switch open, or
24 volt wires improperly
connected or loose.
• Check integrated control
• Blown fuse or circuit
breaker.
• Check for possible shorts
• Integrated control module
has an internal fault.
• Replace bad integrated
• Normal operation.
• Failure to establish flame.
Cause may be no gas to
burners, front cover
pressure switch stuck
open, bad igniter or igniter
alignment, improper
orifices, or coated/oxidized
or improperly connected
flame sensor.
• Loss of flame after
establishment. Cause may
be interrupted gas supply,
lazy burner flames
(improper gas pressure or
restriction in flue and/or
combustion air piping),
front cover pressure
switch opening, or
improper induced draft
blower performance.
• Induced draft blower
pressure switch contacts
sticking.
• Shorts in pressure switch
circuit.
• Pressure switch hose
blocked, pinched or
connected improperly.
• Blocked flue and/or inlet air
pipe, blocked drain system,
or weak induced draft
blower.
• Incorrect pressure switch
setpoint or malfunctioning
switch contacts.
• Loose or improperly
connected wiring.
37
Corrective Action
Cautions and Notes
• Turn power OFF
power to furnace
prior to repair.
integrated control
• Replace integrated
module.
control module
fuse with 3A
module fuse (3A).
automotive fuse.
Replace if necessary.
• Read precautions
in "Electrostatic
in 115 and 24 volt circuits.
Discharge" section
Repair as necessary.
of manual.
control module.
• None. • Normal operation.
• Turn power
• Locate and correct gas
OFF prior to
interruption.
repair.
• Check front cover
pressure switch
operation (hose, wiring,
contact operation).
Correct if necessary.
• Replace or realign
• Igniter is
igniter.
fragile, handle
• Check flame sense
with care.
signal. Sand sensor if
• Sand flame
coated and/or oxidized.
sensor with
• Check flue piping for
emery cloth.
blockage, proper
• See "Vent/Flue
length, elbows, and
Pipe" section
termination.
for piping
• Verify proper induced
details.
draft blower perfor-
mance.
• Replace induced draft • Turn power OFF
blower pressure prior to repair.
switch.
• Replace pressure
switch with proper
replacement part.
• Repair short.
• Inspect pressure • Turn power
switch hose. Repair, if OFF prior to
necessary, repair.
• Inspect flue and/or inlet • Replace
air piping for blockage, pressure
proper length, elbows, switch with
and termination. Check proper
drain system. Correct replacement
as necessary. part.
• Correct pressure
switch setpoint or
contact motion.
• Tighten or correct
wiring connection.