Furnace occasionally smells of exhaust or flue gases inside the home.
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: Flue gas spillage can expose occupants to carbon monoxide. If CO alarms sound or you suspect exhaust in the home, shut off the furnace, ventilate, and call emergency services.
Steps:
- Visual flue check: Inspect the vent pipe from the furnace to the termination for disconnections, corrosion, or blockages.
- Room pressure: Ensure exhaust fans or other appliances are not creating strong negative pressure in the furnace room.
- Professional inspection: A technician should perform a combustion analysis and heat exchanger inspection.
Do not: Do not operate the furnace until the cause is identified and corrected.
Repair Difficulty
Required Part
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