Digital thermostat mounted on a concrete wall
Generic photo: Alexander Mass · Pexels License

Thermostat reads or holds the wrong temperature

Compare the thermostat reading with a reference thermometer at the same spot. If the reading is wrong, look at location, drafts and sensors; if the reading is right but the room never reaches setpoint, the equipment is undersized, starving for air or faulty.

Single source ~30 min easyBrands: All

Before you start

  • Low-voltage work only

Diagnostic steps

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OnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work.

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Thermostat reads or holds the wrong temperature · OnCall Tech