5 red flashes
Rollout / limit-circuit-open hard safety condition
This code typically points to
- Manual-reset rollout switch open
- Combustion air problem
- Inducer problem
- Burner problem
- Heat exchanger issue
Next checks to confirm
- Inspect rollout switch physically
- Verify combustion air and venting
- Inspect burners, heat exchanger, inducer BEFORE resetting
Escalation
Repeated rollout or non-resettable rollout is a hard combustion safety problem.
Reset behavior
Hard lockout; power must be cycled after fault is corrected.
Safety Critical
Immediate concern