Thermostat gets warm and wall behind it is discolored or hot
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: Turn off HVAC power at the breaker before removing the thermostat. If the wall is very hot, stop and call a professional immediately.
- Inspect wiring: Remove the thermostat and check for loose or burnt R and C connections. Tighten or re-strip and reconnect as needed.
- Check wall cavity: If possible, inspect behind the wall for hot pipes or flue vents. The thermostat should not be installed on such walls.
- Relocate thermostat: If the wall is inherently warm, move the thermostat to a cooler interior wall.
If heating appears localized to the thermostat itself with normal wiring and wall temperature, the thermostat has an internal fault and should be replaced.
Repair Difficulty
Required Part
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