Goodman Mfg GKS9 Furnace User Manual


 
35
Circulator blower runs
continuously. No furnace
operation.
Integrated control
module diagnostic LED
is flashing FOUR (4)
flashes.
Primary or auxiliary
limit circuit is open.
Check primary/auxiliary
limit. Replace if
necessary.
Check filters and
ductwork for blockage.
Clean filters or remove
obstruction.
Check circulator blower
speed and perfor-
mance. Correct speed
or replace blower if
necessary.
Tighten or correct
wiring connection.
Turn power OFF
prior to repair.
Replace primary/
auxiliary limit with
proper replacement
part.
Replace blower
with correct
replacement part.
4
4 FLASHES
Faulty primary or auxiliary
limit switch.
Insufficient conditioned air
over the heat exchanger.
Blocked filters, restrictive
ductwork, improper
circulator blower speed, or
failed circulator blower.
Loose or improperly
connected wiring.
Fault Description(s) Possible Causes Corrective Action Cautions and Notes
Symptoms of Abnormal
Operation
Associated
LED Code
2
Normal furnace
operation.
Integrated control
module diagnostic LED
is flashing SEVEN (7)
flashes.
Flame sense
microamp signal is
low.
Sand flame sensor if
coated/oxidized.
Inspect for proper
sensor alignment.
Check inlet air piping
for blockage, proper
length, elbows, and
termination.
Compare current gas
pressure to rating plate
info. Adjust as
needed.
Turn power OFF
prior to repair.
Sand flame sensor
with emery clot.
See “Vent/Flue
Pipe” section for
piping details.
See rating plate for
proper gas
pressure.
7
7 FLASHES
Flame sensor is coated/
oxidized.
Flame sensor incorrectly
positioned in burner flame.
Lazy burner flame due to
improper gas pressure or
combustion air.
Induced draft blower and
circulation blower runs
continuously. No furnace
operation.
Integrated control
module diagnostic LED
is flashing FIVE (5)
flashes.
Flame sensed with
no call for heat.
Correct short at flame
sensor or in flame
sensor wiring.
Turn power OFF
prior to repair.
5
5 FLASHES
Short to ground in flame
sense circuit.
Circulator blower runs
continuously. No furnace
operation.
Integrated control
module diagnostic LED
is flashing SIX (6)
flashes.
Rollout limit circuit is
open.
Check burners for
proper alignment.
Check flue and air inlet
piping for blockage,
proper length, elbows,
and termination.
Correct as necessary.
Check rollout limit.
Replace if necessary.
Check induced draft
blower for proper
performance. Re-
place, if necessary.
Tighten or correct
wiring connection.
Turn power OFF
prior to repair.
See “Vent/Flue
Pipe” section for
piping details.
Replace rollout
limit with correct
replacement part.
• Replace induced
draft blower with
correct replace-
ment part.
6
6 FLASHES
Flame rollout.
Misaligned burners, blocked
flue and/or air inlet pipe, or
failed induced draft blower.
Loose or improperly
connected wiring.
Faulty rollout limit.
Furnace fails to operate.
Integrated control
module diagnostic LED
is flashing continuously.
Polarity of 115 or 24
volt power is
reversed.
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.
C
CONTINUOUS/
RAPID FLASH
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.
Troubleshooting Chart
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.