T
rapid flash
Moderate
Trane · HVAC Systems (AC, Furnaces & Heat Pumps)
Flame Detected Without Call for Heat
Quick Answer
Error code rapid flash on your Trane HVAC Systems (AC, Furnaces & Heat Pumps) means: Flame Detected Without Call for Heat. This is usually fixable — see the step-by-step guide below.
Likely Causes
  1. Leaking gas valve passing gas when the valve should be closed
  2. Short in flame sensor circuit falsely indicating flame presence
  3. Faulty control board flame detection circuitry
How to Fix It
1
Shut off the gas supply to the furnace immediately
2
Check for a gas smell near the burner area using a combustible gas leak detector
3
Disconnect the flame sensor wire and see if the code clears to isolate a wiring short
4
Inspect the gas valve for internal leakage
5
This is a safety-critical condition requiring a licensed HVAC technician for diagnosis and repair
Pro Tip
This fix requires some technical knowledge. If you're unsure about any step, consider contacting support or a qualified technician.
Parts You May Need
Gas valve assembly
Flame sensor
Control board
Related Error Codes
Video Guides
Loading video guides…
Search more on YouTube →