York Gas Furnaces: TM9Y
Re: Diagnostic Codes / Fault Codes
These York gas furnaces have a control board inside the furnace blower compartment that will flash a diagnostic code that shows the operating status of the furnace.
| Diagnostic Codes: | ||
| Slow Green | Normal Operation - no call for heat | |
| Slow Amber | Normal Operation - with a call for HEATING | |
| 4 Amber | No power on "G" during a cooling cycle (power on "Y") |
|
| Flashing Amber | Low flame signal |
|
| Any Color - Steady On | Possible Faulty Control or Blown Fuse |
|
| 1 Red | Flame present with gas off |
|
| 2 Red | Pressure switch stuck closed |
|
| 3 Red | Pressure switch stuck open |
|
| 4 Red |
Limit switch open / open fuse Limit opened 5 times during a heating cycle (1-Hour Lockout) |
|
| 5 Red | Rollout switch open / open fuse (Hard Lockout) |
|
| 6 Red |
Pressure switch opened 4 times in one heating cycle (1-Hour Lockout) |
|
| 7 Red | 3 failed ignition attempts (1-Hour Lockout) |
|
| 8 Red | Flame was established but later lost - 5 times in one heating cycle (1-Hour Lockout) |
|
| 9 Red | Grounding or line polarity fault |
|
| 10 Red | Gas valve circuit shorted |
|
| 11 Red | Extended limit switch open |
|
| 12 Red | Igniter failure |
|
| 13 Red | 2nd Stage Pressure Switch Open with a call for W2 |
|
Fault Code Retrieval: With no thermostat call push and release the LAST ERROR button. The LED will flash up to 5 stored fault codes, beginning with the most recent. If there are no codes in memory, the LED will flash two green flashes.
Clear the Fault Codes: Push and hold the LAST ERROR button for at least five seconds. The LED will flash three green flashes when the memory has been cleared.