Lennox S40 Smart Thermostat
Thermostats
The ultimate controller for more precise comfort
10-Year Limited Warranty
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We have higher standards. Others think so, too.
Year after year, leading institutions choose to award Lennox for its innovative initiatives in product design which helps homeowners define what perfect air means to them. Below you’ll find a recognition this product has received.
Take your home comfort system to the next level
Complement your home comfort system with our suite of technologically advanced accessories to more precisely and efficiently maintain the temperature and air quality in your home.
Smart Room Sensor Smart Air Quality Monitor Wireless Extender
Balanced Temperature and Humidity
The Feels Like™ feature creates the temperature you want to feel, not just the temperature you set—much like the "Feels Like" temperature in a weather report. So when you set it to 72 F, it feels like 72.
Schedule IQ Technology
Uses homeowner inputs and Smart Away™ geo-fencing capabilities to learn your routine and create a schedule that maintains comfort when the home is occupied and help save energy when it's not.
Efficiency at your fingertips
One-touch Away Mode overrides your regular programming schedule with a single touch and sets back your heating and cooling set points to save energy.
Digitally intelligent for precision and efficiency
Digitally intelligent for precision and efficiency
This truly digital product is part of a fully communicating home comfort system. Sensors in the equipment allow the thermostat to diagnose issues and automatically make system adjustments to more precisely and efficiently maintain temperature, humidity and air quality.
Complete control at home or away
Remote control of your home environment is just one touch or voice command away with the Lennox S40 Smart Thermostat. Monitor temperatures and schedules from anywhere in the world using the Lennox Smart Thermostat app on your smartphone or tablet. Available on the App Store and Google Play.
The Lennox S40 Smart Thermostat effortlessly integrates with a range of smart home devices—from premium smart home systems like Control4 to popular virtual assistants like Amazon Alexa and Google Assistant.
Advanced diagnostics keep your system at peak performance
Advanced diagnostics keep your system at peak performance
Protect your investment and peace of mind with active monitoring of system operations through your Lennox S40 Smart Thermostat. This feature is free of charge and provides basic maintenance reminders, alerts you of potential issues, and can even allow you to remotely share diagnostics with your local Lennox dealer to troubleshoot and fix problems. This proactive care helps eliminate downtime and avoid unnecessary service visits and repair costs, ensuring nothing short of perfect air.
The Ultimate Side of Perfect Air
Not only is the Lennox S40 Smart Thermostat part of the Dave Lennox Signature® Collection, it’s part of the Ultimate Comfort System™. This combines the best of everything Lennox has to offer to create an unprecedented whole-home comfort system that seamlessly and intelligently works together to stay finely tuned to your home and deliver consistently clean, perfect air.
Take your home comfort system to the next level
Complement your system with our suite of technologically advanced accessories to more precisely and efficiently maintain the temperature and air quality in your home. The Lennox Smart Air Quality Monitor is the only monitor of its kind that can detect air pollutants and trigger air cleaning on demand. Add on Lennox Smart Room Sensors to more evenly balance temperatures across rooms, plus the Lennox Wireless Extender to nearly double the connection coverage area and ensure you get the most from your communicating equipment. Altogether, it’s the most advanced accessories package available that delivers next-level perfect air.
Ratings & Reviews
See what other customers are saying about
Lennox S40 Smart Thermostat
5/5
Great System - S40 Kmprovements Desired
September 26, 2023
I bought the Signature series hybrid system (heat pump, furnace, purifier, humidifier, S40) and so far it’s a great system. I do like the S40 and would like to suggest a few improvements. - my S40 indoor temp sensor was off by 1 1/2 C so needed adjustment out the box - time zone needs to be set even if getting time from internet (I’d add to instructions) - be better to have display also show % current use of heat pump, furnace, fan as this is very useful in my variable, hybrid system. Be great option. - proximity function needs improving but would be a nice feature if it worked - consider running fan only to cool if outside air cooler than inside (sun can heat up)
Yes, I recommend this product.
St Albert, Alberta Canada
Age: Over 65`
Gender: Male
5/5
3/5
5/5
4/5
Pretty fancy, except for...
September 15, 2023
Very easy to set up and use via the touch screen and menu structure. A couple of things would be nice refinements: 1) in setting the heating schedule how about a "repeat previous day" option? 2) seems to be no easy way to pair a second smart phone with the thermostat. If you live alone this isn't an issue but if your home has multiple occupants just know that only one phone can control the device remotely.
Yes, I recommend this product.
Brighton, UT
Age: 55 - 65
Gender: Male
Reason for Replacement: Planned
4/5
3/5
4/5
5/5
Great Smart Thermostat & Easy to Use
August 29, 2023
I previously had the S30 and upgraded to the S40. Navigation is a little different but easy enough to figure out. The app always pulls up my S40 so I can change the temperature as needed or just check in to see what the temperature in the house is. I love the weather screen saver. Very happy with the S40
Yes, I recommend this product.
Waterford, WI
Age: 55 - 65
Gender: Female
Reason for Replacement: Planned
5/5
4/5
5/5
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