E250
Limit switch circuit open
This code typically points to
- Overfiring
- Heater blockage
- Low airflow
Next checks to confirm
- Check firing rate
- Check for blockage in heater
- Check proper airflow
Escalation
If limit does not close within 3 minutes, unit goes into 1-hour soft lockout
Reset behavior
Resumes normal operation after fault clears.
Safety Critical
Immediate concern