Furnace makes a loud banging or booming noise at startup when burners ignite.
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: Turn off gas and power. Delayed ignition can damage the heat exchanger and is a combustion hazard.
Steps (inspection only):
- Visually inspect burners: Look for rust, debris, or misalignment of burners and crossover ports.
- Do not attempt gas adjustments: Gas pressure and valve timing must be checked with proper instruments.
Contact a qualified HVAC technician to remove and clean burners, verify gas pressure, and inspect the heat exchanger for damage.
Repair Difficulty
Required Part
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