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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
4/5
Other reviews are too harsh
May 16, 2024This was installed recently with my new high efficiency Lennox furnace and AC. So far it works mostly as advertised and I am not upset with it. The screen is a bit dark with a small font, so I recommend the manual setting for brightness. The proximity sensor does not work, but just touch it and it comes to life. The display is appealing. Setting it up was easy; programming to the desired set points is straight forward, and it has a lot of options to help get the temp/humidity just the way you like it. I think it is off by 2 degrees (display temp is higher than actual, but that is not a game changer for me). I downloaded the APP so I can control it and check the temp/humidity from my phone (a feature I never thought I needed, but now I really like it). Overall, I'd say if your Lennox dealer recommends it for controlling your system, do not be concerned and go for it.
Yes, I recommend this product.
Lambertville, NJ
Age: 55 - 65
Gender: Female
Reason for Replacement: Planned
4/5
3/5
5/5
4/5
Disappointed with S40 Thermostat Proximity Sensor
April 08, 2024I just had a new Lennox HVAC system installed with the S40 Thermostat. From the initial installation, the proximity sensor feature didn't work, and installers couldn't figure it out. Decided to do some research after they left, and found that just about everyone has problems with it. Twice the thermostat rebooted after installers left, and had to go through initial set-up again. For what I paid, I would expect a much better product that works as described.
Pittsburgh PA
Age: 55 - 65
Gender: Male
Reason for Replacement: Planned
3/5
2/5
3/5
3/5
Directions for use would be handy
March 11, 2024It would be handy to have directions for use provided at point of sale and installation. It also would be nice if the directions explained how to set and edit notifications. The available user guide is not user friendly in this regartd.
Yes, I recommend this product.
Maryland
Age: Over 65`
Reason for Replacement: Emergency
3/5
2/5
3/5
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