Control indicates hard lockout, furnace will not attempt ignition until reset
Safety Warning
This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.
If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.
Possible Causes
How to Fix / Troubleshooting
Safety: Investigate the cause of lockout before repeatedly resetting. Repeated failed ignition can lead to raw gas accumulation.
Steps to check:
- Reset procedure: Turn off power to the furnace for at least 30 seconds, then restore. Some Trane models may also require thermostat reset.
- Review recent issues: If you have seen codes for ignition failure, flame loss, or gas valve faults, address those root causes (ignitor, flame sensor, gas supply) before further operation.
- Observe a cycle: After reset, watch a full ignition sequence. If it fails again, do not continue cycling power.
When to call a professional: A hard lockout that returns indicates a serious underlying fault. Have a Trane-qualified technician perform full diagnostics on ignition, gas train, and controls.
Repair Difficulty
Required Part
We may earn a commission from links on this page.