Furnace ignites but produces yellow, lazy flames or soot around the burner area.
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
Critical Safety: Yellow flames and soot indicate carbon monoxide risk. Turn off furnace and call a professional immediately.
Steps (visual only):
- Turn off gas and power.
- Inspect burners: Look for heavy rust or debris. Do not attempt major adjustments yourself.
Combustion issues must be corrected by a licensed HVAC technician using proper instruments. Do not operate the furnace until it is inspected.
Repair Difficulty
Required Part
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