Furnace ignites but flame appears mostly yellow or orange and may produce soot.
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. Yellow, sooty flames can indicate dangerous carbon monoxide production.
- Do not operate: If you see yellow, lazy flames or soot around the burner area, shut the furnace down and ventilate the area.
- Check combustion air openings: Ensure furnace room vents or louvered doors are not blocked. For sealed combustion Carrier models, verify intake PVC is not obstructed.
Burner cleaning, gas pressure adjustment, and combustion analysis must be performed by a licensed HVAC technician with proper instruments.
Repair Difficulty
Required Part
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