Thermostat shows significantly incorrect room temperature (e.g., always 3–5°C off) but no error code is displayed.

Safety first: Turn OFF power at the breaker if you need to remove the thermostat from the wall.

Steps to correct:

• Compare with a reference: Place a reliable thermometer at the same height and location as the thermostat and compare readings.
• Adjust calibration: In the Mysa app or on the thermostat, use the temperature offset/calibration setting to correct the reading.
• Improve placement: If the thermostat is near a heat source or draft, relocate it to a more representative location.

If large errors remain even after calibration and proper placement, the internal sensor may be defective. Replace the thermostat.