22
Abnormal flame-proving signal
This code typically points to
- Flame sensed while gas valve is de-energized
- Leaky/stuck-open gas valve
- Flame-rectification/control issue
Next checks to confirm
- Shut off external gas supply and observe whether code clears
- If code clears, suspect leaking gas valve
- If code persists with gas off, isolate flame-sensing/control circuit
Escalation
Persistent false flame with gas physically shut off moves suspicion toward board/flame circuit.
Reset behavior
Inducer runs until fault clears.
Safety Critical
Immediate concern