How do I change the date & time in my S40 Smart Thermostat?
FAQ , Thermostats , Troubleshooting Modified: March 19, 2026
Date and time typically come from Lennox if your thermostat is connected to WiFi. If your thermostat is not connected to WiFi, then you can set the date and time manually by going into your thermostat to Menu > Display settings > Date & time.
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