S40 showing to be 3 or 4 degrees off from what the temperature is in the home based on a different thermometer in the home.
FAQ , Thermostats , Troubleshooting Modified: March 19, 2026
The discrepancy in temperature readings could be due to a few reasons. the s40 smart thermostat's sensor might need calibration. the thermostat allows for calibration of the sensor if the indoor temperature displayed on the controller differs from the actual indoor temperature. this can be done through the room temperature sensor calibration button in the service menu. another reason could be the location of the thermostat. if it's placed near a heat source, in direct sunlight, or in a drafty area, it might not accurately reflect the overall temperature of the home. lastly, it's also possible that the other thermometer you're comparing it to is not accurate. it's recommended to compare the thermostat's reading with a few different thermometers to ensure accuracy.
For more information or a visual representation of steps please reference our user guide here
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