How to Fix / Troubleshooting

Critical safety: Delayed ignition can cause damage and is a fire hazard. Turn off gas and power before working on burners.

Inspect burners: Remove burner assembly and check for rust, debris, or misalignment. Clean with a soft brush and compressed air.
Check ignitor position: Ensure the hot surface ignitor is correctly positioned in front of the burner where gas first exits.
Reassemble carefully: Reinstall burners in the exact original order and orientation. Ensure they seat properly on the manifold.
Test ignition: Restore power and gas, then observe several ignition cycles. If booming persists, shut down and call a professional to check gas pressure and combustion.

Do not continue operating a furnace with delayed ignition.

Furnace makes loud booming or banging noise at burner ignition

Possible Causes