Coleman Furnace Error Codes

There are the lists of possible Coleman furnace problems which may happen to different modifications of this item during its operation. The Coleman furnace error codes are presented as various types of flashes and LED signals. They are divided onto groups by color, and detailed description for each type of signals is provided.

For each of the codes there is a condition column with explanation the cause of the problem. For example, Coleman furnace error code 7 means there is no ignition and you need to check the flame and possible reasons why it is absent. Be careful with the repair works and call the specialists if you do not have necessary qualification.

Coleman GM8S060A12UH11 Furnace Error Codes

Flashes Color Condition
Off Red No Line Power to Control.
1 Flame present with gas off.
2 Pressure switch closed with inducer pressure below allowed tolerance.
3 Pressure switch open with inducer pressure above allowed tolerance.
4 High Limit Switch open. Fuse open, or Sensor temperature above allowed limit.
5 Auxiliary Limit String or Safety Relay open when it should be closed.
6 Modulated Gas Valve current failure.
7 Lockout due to no ignition. (Flame could not be sensed).
8 Lockout due to flame recycles. (Flame is lost after being sensed).
9 Incorrect line voltage polarity.
10 Gas valve circuit is shorted.
11 Main Blower Failure.
12 Identity Plug loose or missing.
Steady On Control Fault Detected; No 24 Volt Power
Slow Green Normal Operation – No call for heat.
Slow Amber Gas Oil – Call for Heat. (Control is in ignition process, flame has not been sensed.)
1 Call for Cooling.
2 Gas On – Call for Heat
3 Gas On – No Call for Heat
4 Suppressed firing rate due to Soft Limit.
5 Suppressed firing rate due to Low Combustion Air.
6 Heat Pump Heating Operation
7 Compressor ON – No Call for Cooling
Rapid Flame sense current is below 1.5 Microamps.
Rapid Green Control is in “Test Mode” with no call for heat.

Coleman GM8S130D20UH11 Furnace Error Codes

Color LED Description Solution
RED STEADY ON RED: The test button is depressed
GREEN RAPID GREEN FLASH: indicates that furnace in factory test mode
GREEN FLASH: indicates a low firing rate heating cycle is underway.
indicates a medium firing rate heating cycle is underway.
indicates a high firing rate heating cycle is underway

Coleman FC8T060A12UH11 Furnace Error Codes

Green LED Description
Steady OFF Internal control fault or no power
Steady ON Normal operation, no call for heat
Fast Flash Normal operation, call for heat present
1 flash Pressure switch does not close within 30 seconds of inducer energized.
Pre-Purge – The control energizes the induced draft motor and waits for the pressure switch to dose. If the pressure switch does not close within 30 seconds of the inducer energizing, the control will flash *1″ on the LED. The control will leave the inducer energized indefinitely as long as the call for heat remains and the pressure switch is open.
2 flashes Pressure switch Is closed before inducer is energized.
Call for Heat – The control checks to see if the pressure switch is open. If the pressure switch is closed, the control will flash m T on the LED and wait indefinitely for the pressure switch to open.
3 flashes Limit switch is open
Limit Operation – The limit switch is ignored unless a call for heat is present (W energized). If the limit switch is open and a call for heat is present, the control de-energizes the gas valve and runs the indoor blower motor on heat speed, and runs the induced draft motor. The control will flash “3″ on the LED until the limit switch closes. When the switch re-closes or the call for heat is lost, the control runs the induced draft motor through post-purge and runs the indoor blower through the selected fan off delay. The control will return to normal operation after the blower off delay is completed.
4 flashes In lockout from failed ignitions or flame losses
Ignition Retry – If flame is not established on the fifth tnal for ignition (initial try + 4 re-tnes). the control de-energizes the gas valve and goes into lockout. The control flashes a *4″ on the LED to indicate ignition failure lockout.
5 flashes Twin communications fault
A Twin Communications Fault will occur if the 24 VAC supply to the twins are not in phase with each other, or power is removed from one of the twins. While a Twin Fault exists, the control does not respond to thermostat commands and flashes “5” on the status LED. Open limit and undesired flame response are still operational. The control continually tries to establish communication and automatically resumes normal operation when communication is re-established. If a twin fault occurs during a heat cycle, both furnaces terminate the call for heat immediately. The only chance for blower mis-synchronization is if the blower off delays are set differently on the twins. If a twin fault occurs during high speed fan or continuous fan. both controls shut blowers off immediately.
6 flashes Limit Switch tripped 5 times during heat cycle
Limit Operation – If the limit switch has 5 trips per call for heat, the control will go into a hard lockout and the LED will flash 6. Lockout may be manually reset by removing power from the control for more than 1 second or removing the thermostat call for heat for more than 1 and less than 20 seconds
7 flashes 5 flames losses during one heat cycle.
Ignition Re-Cycle – The control will re-cycle up to 5 flame losses (4 re-cycles) within a single call for heat before going to lockout. The LED will flash 7 during this lockout.