Goodman Mfg GKS9 Furnace User Manual


 
34
1
Integrated control module will automatically attempt to reset from lockout after one hour.
Troubleshooting Chart
Furnace lockout due
to an excessive
number of ignition
“retries” (3 total)
1
.
Locate and correct
gas interruption.
Check front cover
pressure switch
operation (hose, wiring,
contact operation).
Correct if necessary.
Replace or realign
igniter.
Check flame sense
signal. Sand sensor if
coated and/or oxidized.
Check flue piping for
blockage, proper
length, elbows, and
termination.
Verify proper induced
draft blower perfor-
mance.
Turn power
OFF prior to
repair.
Igniter is
fragile, handle
with care.
Sand flame
sensor with
emery cloth.
See “Vent/Flue
Pipe” section
for piping
details.
Furnace fails to operate.
Integrated control module
diagnostic LED is
flashing ONE (1) flash.
1
1 FLASH
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 (im-
proper gas pressure or
restriction in flue and/or
combustion air piping), front
cover pressure switch
opening, or improper
induced draft blower
performance.
Pressure switch
circuit is closed.
Induced draft
blower is not
operating.
Replace induced draft
blower pressure
switch.
Repair short.
Turn power OFF
prior to repair.
Replace pressure
switch with proper
replacement part.
Furnace fails to operate.
Integrated control module
diagnostic LED is
flashing TWO (2)
flashes.
2
2 FLASHES
Induced draft blower
pressure switch contacts
sticking.
Shorts in pressure switch
circuit.
Inspect pressure
switch hose. Repair, if
necessary,
Inspect flue and/or inlet
air piping for blockage,
proper length, elbows,
and termination. Check
drain system. Correct
as necessary.
Correct pressure
switch setpoint or
contact motion.
Tighten or correct
wiring connection.
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.
Pressure switch
circuit not closed.
Induced draft blower
is operating.
Induced draft blower
runs continuously with
no further furnace
operation.
Integrated control module
diagnostic LED is
flashing THREE (3)
flashes.
3
3 FLASHES
Turn power
OFF prior to
repair.
Replace
pressure
switch with
proper
replacement
part.
Fault Description(s) Possible Causes
Associated
LED Code
2
• Normal Operation • Normal Operation None
• Normal Operation
ON
CONTINUOUS
ON
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.
Manual disconnect switch
OFF, door switch open, or
24 volt wires improperly
connected or loose.
Blown fuse or circuit
breaker.
Integrated control module
has an internal fault.
Assure 115 and 24 volt
power to furnace
integrated control
module.
Check integrated control
module fuse (3A).
Replace if necessary.
Check for possible shorts
in 115 and 24 volt circuits.
Repair as necessary.
Replace bad integrated
control module.
Turn power OFF
prior to repair.
Replace
integrated
control module
fuse with 3A
automotive fuse.
Read precautions
in “Electrostatic
Discharge” section
of manual.
Furnace fails to operate.
Integrated control module
diagnostic LED provides
no signal.
NONE
Fault Description(s) Possible Causes Corrective Action
Cautions and Notes
Symptoms of Abnormal
Operation
Associated
LED Code
2
2
LED Flash code will cease if power to the control module is interrupted through the disconnect or door switch.
• LED is Steady On.