A126_F
Flame not sensed with gas valve on - UL (safety supervision)
This code typically points to
- UL-supervised flame-absence abnormality during valve-on condition
Next checks to confirm
- Verify valve command and flame-sense state
- Detailed tree not printed in accessible snippet
Escalation
Safety-related abnormal flame supervision
Reset behavior
Clears when supervised condition is corrected; may require power/heat-call reset depending sequence.
Safety Critical
Immediate concern