Furnace makes loud banging or booming noise at startup.
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: Delayed ignition can be dangerous. Turn off power and gas if bangs are loud or frequent, and do not continue to operate the furnace.
- Visual burner inspection: Remove the burner access panel and inspect burners for rust, debris, or misalignment. Do not attempt to modify orifices.
- Clean burners (if accessible): Carefully remove burners one at a time, brush off debris, and blow out ports with compressed air. Reinstall in the same order and orientation.
- Check for gas odor: If you smell gas before ignition, shut off gas and call a professional immediately.
Gas pressure and valve timing must be checked by a licensed technician. Do not attempt adjustments yourself.
Repair Difficulty
Required Part
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