Troubleshooting Chart - Amana GUCA045AX30 Service Instructions Manual

Associated
Symptoms of Abnormal
LED Code
Operation
(See Note 2)
- No 115 V power to furnace, or no 24 V
- Furnace fails to operate. power to integrated control module.
and
None
- Integrated control module diagnostic - Blown fuse, or circuit breaker.
LED provides no signal.
- No signal from thermostat.
- Furnace fails to operate.
ON
and - Integrated control module has an
- Integrated control module diagnostic internal fault.
Continuous
LED is lit continuously.
On
- Furnace is not operating - Furnace lockout due to an excessive
1
and number of ignition "retries" (3 total
- Integrated control module diagnostic attempts), or "recycles" (5 total
LED is flashing one flash. 1 Flash recycles). See note 1.
- Furnace fails to operate.
- Pressure switch circuit is closed
and
2
even though induced draft blower
- Integrated control module diagnostic
is not operating.
LED is flashing two flashes.
2 Flashes
- Induced draft blower runs continuously
with no further furnace operation. - Pressure switch circuit does not
and close in response to induced draft
1 3
- Integrated control module diagnostic blower operation.
LED is flashing three flashes.
3 Flashes
- Circulator blower runs continuously
with no further furnace operation.
4
- Primary limit circuit is open.
and
(Primary or auxiliary limit).
- Integrated control module diagnostic
LED is flashing four flashes.
4 Flashes
- Circulator blower runs continuously
with no further furnace operation.
5
and - Rollout limit circuit is open.
- Integrated control module diagnostic
LED is flashing five flashes.
5 Flashes
- Furnace fails to operate.
6
and - Polarity of 115 V or 24 V AC power
- Integrated control module diagnostic is reversed.
LED is flashing six flashes.
6 Flashes
Notes:
1) Integrated control module will automatically attempt to reset from lock out after one hour.
2) LED flash code will cease if power to the control module is interrupted through the disconnect or door switch.
3) Integrated control module will automatically attempt to reset from lock out after 20 minutes.

TROUBLESHOOTING CHART

Fault Description(s) Possible Causes
- Manual disconnect switch OFF, door switch open,
or 24 V wires miswired, loose or misconnected wires.
- Blown fuse, or circuit breaker.
- Improper thermostat connection or setting.
- Integrated control module has an
internal fault.
- 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 misconnected
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
misconnected.
- Blocked flue and/or inlet air pipe, blocked drain
system, or weak induced draft blower.
- Incorrect pressure switch set point or
malfunctioning switch contacts.
- Loose or misconnected wiring.
- Insufficient conditioned air over the heat exchanger.
Cause may be blocked filters, restrictive
ductwork, improper circulator blower speed, or
failed circulator blower.
- Loose or misconnected wiring.
- Rollout limit(s) is(are) open due to flame rollout.
Cause may be misaligned burners, blocked flue
and/or air inlet pipe, or failed induced draft blower.
- Loose or misconnected wiring.
- Polarity of 115 V AC power to furnace or
integrated control module is reversed.
- Orange and gray wires to transformer are reversed.
- Poor unit ground.
Corrective Action
- Assure 115 V and 24 V power to furnace and integrated
control module.
- Check integrated control module fuse (3 A). Replace if necessary.
- Check for possible shorts in 115 V and 24 V circuits. Repair as necessary.
- Replace bad integrated control module with known
good control module.
- 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/oxidized.
- Check flue piping for blockage, proper length, elbows, and termination.
- Verify proper induced draft blower performance.
- Replace induced draft blower pressure switch if bad.
- Check for and correct shorted wiring.
- Check and correct pressure switch hose.
- Check flue and/or inlet air piping for blockage, proper length, elbows
and termination. Check drain system.
- Verify proper pressure switch set point and contact motion.
- Check and correct wiring.
- Check filters and ductwork for blockage. Clean filters or remove obstruction.
- Check for proper circulator blower speed and performance. Correct speed or
replace blower if necessary.
- Check and correct wiring.
- Check burners for proper alignment.
- Check flue and/or air inlet piping for blockage, proper length, elbows, and termination.
- Check induced draft blower for proper performance. Replace if necessary.
- Check and correct wiring.
- Review wiring diagram.
- Verify proper grounding.
- Check and correct wiring.
Sheet 1 of 2
Cautions and
Notes
- Turn power OFF prior to repair.
- Replace integrated control module fuse with 3 A automotive
style fuse.
- Turn power OFF prior to repair.
- Read precautions in "Electrostatic Discharge"
section of manual.
- Turn power OFF prior to repair.
- Ignitor is fragile, handle with care.
- Sand flame sensor with emery cloth
- See "Flue and Combustion Air Pipe" section for piping details.
- Turn power OFF prior to repair.
- Replace pressure switch with proper replacement part.
- Turn power OFF prior to repair.
- See "Flue and Combustion Air Pipe" section for piping details.
- Replace pressure switch with proper replacement part.
- Turn power OFF prior to repair.
- See Specification Sheet for allowable rise range and proper
circulator blower speed.
- Turn power OFF prior to repair.
- See "Flue and Combustion Air Pipe" section for piping details.
- Replace induced draft blower with proper replacement part.
- Turn power OFF prior to repair.