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Lennox S40 Smart Thermostat
Thermostats
The ultimate controller for more precise comfort
Price Guide
$$$$
Warranty
10-Year Limited Warranty
Features
Ratings & Reviews
See what other customers are saying about
Lennox S40 Smart Thermostat
3/5
Great size and screen, but issues
October 27, 2026My wife and I both connected to S40 via the app. The app says 2 devices are connected. I have an iPhone, she has an Android. We followed all the instructions for changing permissions on her Android so “Away” mode activates when we both are gone. This weekend we went on a trip and the thermostat never activated to Away. Bummer Google Nest doesn’t work with it
Uertzjl
ATL
Age: 45 to 54
Gender: Male
Reason for Replacement: Planned
Features:
5/5
5/5
Price:
3/5
3/5
Warranty Satisfaction:
3/5
3/5
3/5
5/5
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