Trane Gas Furnaces: TUH1/TDH1
Re: Furnace Lockout Codes / Diagnostic Codes
| INTEGRATED FURNACE CONTROL - ERROR CODES | |
| Flashing Slow | Normal - No call for heat |
| Flashing Fast | Normal - Call for heat |
| On | Replace Control |
| Off | Check Power |
| 2 Flashes | Lockout due to re-tries or recycles |
| 3 Flashes | Pressure switch fault (open or closed) |
| 4 Flashes | Open limit circuit |
| 5 Flashes | Flame sensed with no call for heat |
| 6 Flashes | Reversed polarity, low voltage or poor ground |
| 7 Flashes | Gas valve circuit error |
| 8 Flashes | Low flame signal |
| 9 Flashes | Check Ignitor, Possible grounding problem |