5 flashes
Flame sensed when no flame should be present
This code typically points to
- Slow-closing or leaking gas valve
- Leftover flame at end of heat cycle
- Flame-sense circuit short or noise
Next checks to confirm
- Verify no actual flame is present
- Confirm gas valve is truly de-energized
- Inspect flame-sense path and ground
Escalation
Confirmed gas leakage or valve not closing is a serious safety issue.
Reset behavior
Stored in memory; auto-erased after 14 days.
Safety Critical
Immediate concern