What is Sensor Temperature Difference Limit?
FAQ , Thermostats , Troubleshooting Modified: March 19, 2026
This setting determines the temperature differential limit between the smart room sensor and the S40 thermostat. Set default temperature difference is 7ºF. The system compares the smart room sensor and thermostat temperature difference. If the temperature difference between the smart room and thermostat temperatures is greater than 7ºF then the system determines there is a potential issue with smart room sensor temperature. The system will then raise a warning on the thermostat and will only use the thermostat temperature reading and ignore the smart room sensor reading until the issue is resolved.
You can change the sensor temperature difference limit setting to a range between 2 to 10ºF and can be incremented 1 degree at a time.
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