Troubleshooting - Amana GMSS9 Series Service Instructions Manual

TROUBLESHOOTING

Symptoms of Abnormal
Operation
• Furnace fails to
operate.
• Integrated control
module diagnostic LED
provides no signal.
• LED is 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.
2
LED Flash code will cease if power to the control module is interrupted through the disconnect or door switch.
Associated
Associated Fault
Fault
Description(s)
LED Code 2
Description(s)
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 to an exces-
1
sive number of
ignition "retries" (3
1 FLASH
1
total) .
• Pressure switch
circuit is closed.
2
• Induced draft
blower is not
2 FLASHES
operating.
• Pressure switch
circuit not closed.
3
• Induced draft
blower is
3 FLASHES
operating.
Possible Causes
Possible Causes
• Manual disconnect
• Assure 115 and 24 volt
switch OFF, door
switch open, or 24 volt
wires improperly
• Check integrated control
connected or loose.
• Blown fuse or circuit
breaker.
• Check for possible shorts
• Integrated control
module has an internal
fault.
• Replace bad integrated
• Normal Operation • None
• 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.
• Inspect pressure
• Pressure switch hose
blocked, pinched or
connected improperly.
• Inspect flue and/or
• Blocked flue and/or inlet
air pipe, blocked drain
system, or weak induced
draft blower.
• Incorrect pressure switch
setpoint or malfunctioning
switch contacts.
• Correct pressure
• Loose or improperly
connected wiring.
• Tighten or correct
Corrective Action Cautions and
• Turn power OFF
prior to repair.
power to furnace integrated
control module.
• Replace inte-
grated control
module fuse with
module fuse (3A). Replace
if necessary. 3A automotive
fuse.
• Read precautions
in 115 and 24 volt circuits.
in "Electrostatic
Repair as necessary.
Discharge"
section of manual.
control module.
• Normal Operation
• Locate and correct gas
• Turn power
interruption.
OFF prior to
repair.
• Check front cover
pressure switch
• Igniter is
operation (hose, wiring,
fragile, handle
contact operation).
with care.
Correct if necessary.
• Clean flame
• Replace or realign
sensor.
igniter.
• See "Vent/
• Check flame sense
Flue Pipe"
signal. Clean sensor if
section for
coated and/or oxidized.
piping details.
• Check flue piping for
blockage, proper length,
elbows, and termination.
• Verify proper induced
draft blower perfor-
mance.
• Turn power OFF
• Replace induced
prior to repair.
draft blower
• Replace pressure
pressure switch.
switch with
• Repair short.
proper replace-
ment part.
• Turn power
switch hose. Repair,
OFF prior to
if necessary,
repair.
• Replace
inlet air piping for
pressure
blockage, proper
switch with
length, elbows, and
proper
termination. Check
replacement
drain system. Correct
part.
as necessary.
switch setpoint or
contact motion.
wiring connection.
Notes
43