C
22
Moderate
Carrier · Central Air Conditioners & Furnaces
Abnormal Flame Proving Signal
Quick Answer
Error code 22 on your Carrier Central Air Conditioners & Furnaces means: Abnormal Flame Proving Signal. This is usually fixable — see the step-by-step guide below.
Likely Causes
  1. Flame sensor detecting flame when gas valve should be closed
  2. Leaking gas valve allowing gas to pass when de-energized
  3. Short circuit in flame sensor wiring
  4. Gas valve relay on control board stuck closed
How to Fix It
1
Turn off gas supply immediately as this code indicates a potential gas leak
2
Inspect gas valve for signs of leaking (use a combustible gas detector)
3
Check flame sensor wiring for shorts to ground or to other circuits
4
Test gas valve by disconnecting power leads and checking if gas still flows
5
This is a safety-critical fault. A licensed HVAC technician must diagnose and repair this issue
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
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