GCSS96 Installation Manual

40
T ROUBLESHOOTING C HART
2
LED Flash code will cease if power to the control module is interrupted through the disconnect or door switch.
•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 performance.
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 pirmary 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.
• Inspect for proper sensor
alignment.
• Compare current gas
pressure to rating plate
info. Adjust as needed.
• Turn power OFF prior to
repair.
• Clean flame sensor with steel
wool.
• 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.
• Furnace fails to operate.
• Integrated control module
diagnostic LED is flashing
SIX (6) flashes.
• No furnace operation.
• Rollout limit open.
•Integrated control
module fuse is
blown.
• 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.
Replace, if necessary.
•Tighten or correct wiring
connection.
• Turn power OFF prior to
repair.
• See “Vent/Flue Pipe” section
for piping details.
•Replace induced draft blower
with correct replacement
part.
•Replace integrated control
module fuse with 3A
automotive fuse.
• Read precautions in
“Electrostatic Discharge”
section of manual.
• Replace rollout limit with
correct replacement 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.
• Short in 24 volt AC control
circuits or safety circuits.
• 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.
• 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.
C
CONTINUOUS/
RAPID FLASH
7
8 FLASHES
8
• Furnace not operating.
• Integrated control module
diagnostic LED is flashing
EIGHT (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.
•Replace bad igniter.
•Check & correct unit
ground wire.
•Replace bad integrated
control module.
• Turn power OFF prior to
repair.
• Replace igniter w/proper
replacment part.
• Read precautions in
“Electrostatic Discharge”
section of manual.
• LED is steady on.
STEADY ON • Normal operation.
• Circulating blowers not
operating simultaneously.
No blower operation.
C
9
9 FLASHES
•Twinning Fault
• Furnace twin terminals not
connected together by field
wiring.
• Isolating relay not used or
improperly installed
• Install field wiring
connecting twin terminals,
check continuity of wiring.
• Verify each furnace fan
motor is operable without
twinning connection.
•Wire per twinning diagram
in this installation manual
• Verify line voltage supply is
turned off before proceeding
with corrections.