How do I prevent my kids from messing with the S40 Smart Thermostat?
FAQ , Thermostats , Troubleshooting Modified: March 19, 2026
The screen lock feature of the S40 thermostat is located under Menu > Display Settings > Screen. The options are: Unlocked (default), Partially Locked (where you can allow others to only adjust the set-points but nothing else) and Locked (where no changes can be made, and the thermostat is in display only mode). When the thermostat screen is locked, the lock icon appears on the home screen. To unlock it, press and hold the lock icon.
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