Soot or black staining is visible around the flue terminal or on the heater casing.
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 gas and power. Sooting indicates dangerous combustion conditions and potential carbon monoxide production.
- Do not continue operation: Leave the heater off until inspected.
- Check for obvious obstructions: Ensure the flue terminal is not blocked by debris, covers, or structures.
A licensed gas technician must clean the burners and heat exchanger, verify gas pressure, and correct any flue or air supply issues.
Repair Difficulty
Required Part
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