13
Flame lost / flame failure after establishment
This code typically points to
- Flame loss after establishment
- Weak flame sense
- Gas-delivery instability
Next checks to confirm
- Accessible snippet does not expose a separate 13 chart on this exact manual page
- Use flame-sense, gas pressure, grounding, and carryover checks if 13 is the underlying fault alternating with 10
Escalation
Five flame losses in one heat call contribute to one-hour soft lockout
Reset behavior
Clears with normal flame stability or via soft-lockout reset if wrapped by 10.
Urgent
Fix now