15
Symptoms of Abnormal
Operation
Associated
LED Code
(See Notes 1 & 2)
Probable Cause(s)
Corrective Action
- Furnace fails to operate.
and
- Integrated control module diagnostic
LED provides no signal.
None
- No electrical power to furnace.
- Confirm that the external electrical disconnect switch is in the "ON" position.
If "OFF", switch to the "ON" position.
- Check for tripped or blown circuit breaker or fuse. Replace if necessary.
- Furnace fails to operate.
and
- Integrated control module diagnostic
LED is lit continuously.
Continuous
On
- Integrated control module has an
internal fault.
- Have servicer inspect furnace and replace faulty integrated control module if
necessary.
- Furnace is not operating
and
- Integrated control module diagnostic
LED is flashing one flash.
1 Flash
(See Note 3)
- No gas supply to furnace.
- Condensate drain blocked.
- Confirm that the external manual gas shut-off valve is in the "Open" position.
If "Closed", follow the start up procedure outlined in this manual when
moving the gas shut-off valve to the "Open" position.
- Check drain system for blockage
- Furnace fails to operate.
and
- Integrated control module diagnostic
LED is flashing two flashes.
2 Flashes
- Possible pressure switch malfunction.
- Have servicer inspect furnace and make necessary corrections.
- Induced draft blower runs continuously
with no further furnace operation.
and
- Integrated control module diagnostic
LED is flashing three flashes.
3 Flashes
- Blocked flue and/or inlet air pipe.
- Blocked drain system.
- Check flue and/or inlet air piping for blockage, especially at the outdoor
termination(s).
- Check drain system for blockage. Clear if possible
- Circulator blower runs continuously
with no further furnace operation.
and
- Integrated control module diagnostic
LED is flashing four flashes.
4 Flashes
- Dirty filters or blocked return grilles.
- Check filters. Repace or clean if necessary.
- Check for furniture, curtains, etc. blocking return grilles. Correct if
necessary.
- Furnace fails to operate.
and
- Integrated control module diagnostic
LED is flashing six flashes.
6 Flashes
- Polarity of electrical power to furnace
or control module has been reversed.
- Poor unit ground.
- Have servicer inspect furnace and make necessary corrections.
- Normal furnace operation.
but
- Integrated control module diagnostic
LED is flashing seven flashes.
7 Flashes
- Flame sensor is coated/oxidized.
- Flame sensor is incorrectly positioned
in burner flame
- Have servicer inspect furnace and make necessary corrections.
- Furnace is not operating.
and
- Integrated control module diagnostic
LED is flashing eight flashes.
8 Flashes
- Possible igniter or integrated control
module problem.
- Have servicer inspect furnace and make necessary corrections.
- Furnace operating on low stage with
temperature of conditioned air lower than
typical.
and
- Integrated control module diagnostic
LED is flashing nine flashes.
9 Flashes
- Blocked flue and/or inlet pipe.
- Check flue and/or air inlet piping for blockage, especially at the outdoor
termination(s).
- Induced draft and circulator blower run
continuously with no further
furnace operation.
and
- Integrated control module diagnostic
LED is flashing continuously.
Continuous
Flashing
- Malfunction in flame sense circuit.
- Have servicer inspect furnace and make necessary corrections.
2) LED flash code will cease if power to the control module is interrupted through the disconnect or furnace door switch.
1) LED flash code may be viewed through sight glass in blower compartment door.
3) Integrated control module will automatically attempt to reset from "lock out" (1 Flash) after one hour.
1
1
3
4
ON
C
6
7
8
9
2
Troubleshooting / Before You Request a Service Call
