York Gas Furnaces: TM9T
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 | |
Rapid Amber | Low flame signal |
|
4 Amber | No Call for G. |
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Rapid Red | Twinning error; incorrect phasing |
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1 Red | Flame present with gas off |
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2 Red | Pressure switch stuck closed |
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3 Red | Pressure switch stuck open |
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4 Red | Limit switch open / open fuse |
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5 Red | Rollout switch open / open fuse |
|
6 Red |
4 open pressure switch faults in one heating cycle |
|
7 Red | 3 failed ignition attempts |
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8 Red | Flame was established but later lost - 5 times in one heating cycle |
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9 Red | Grounding or line polarity fault |
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10 Red | Gas valve circuit shorted |
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11 Red | Extended limit switch open |
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12 Red | Igniter failure |
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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.