Furnace is very old and heat exchanger shows signs of rust, cracks, or soot buildup.
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
Danger: A cracked heat exchanger can leak carbon monoxide. If you suspect a crack, shut off the furnace and do not operate it until inspected.
Steps:
- Visual inspection: With power off, inspect visible portions of the heat exchanger for rust flakes, holes, or cracks.
- Check for soot: Soot around burners or in the furnace cabinet can indicate improper combustion.
- Use CO detectors: Ensure working carbon monoxide detectors are installed near sleeping areas.
When to call a technician: Heat exchanger evaluation and replacement are strictly professional tasks. Replacement of the furnace is often recommended.
Repair Difficulty
Required Part
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