Furnace LED flashes code 34; ignitor may not glow or glows weakly, no burner ignition.
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 first: Turn off power and gas before servicing the ignitor.
- Visual inspection: Remove the burner compartment door and locate the hot surface ignitor near the burners. Inspect for cracks, chips, or white chalky buildup.
- Check connector: Ensure the ignitor's plug is firmly connected to the harness and not burned or loose.
- Do not touch element: Oils from skin can shorten ignitor life. Handle only by the ceramic base.
- Replace ignitor: If damaged, replace with the exact Day & Night-approved ignitor model for your furnace. Mount it in the same position and gap relative to the burner.
After replacement, restore power and gas, then call for heat to verify proper ignition. If code 34 persists, the control board's ignitor circuit or line voltage supply may be faulty.
Repair Difficulty
Required Part
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