Trane XR80 furnace provides a LED on its integrated furnace control for quick diagnostic. Here is its diagnostic code:
LED Flash
Error
Flashing Slow
Normal No Call for Heat
Flashing Fast
Normal Call for Heat
Continuous On
Replace Control
Continuous Off
Check Power
2 Flashes
External Lockout (Retries or Recycles Exceeded)
3 Flashes
Pressure Switch Error
4 Flashes
Open High Limit Device
5 Flashes
Flame Sensed when NO flame should be present
6 Flashes
115 [...]
