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Lennox

Lennox S40 (22V24) Smart Thermostat, Touchscreen, WiFi, Communicating System Control, Programmable, High Efficiency, Geo-Fencing, Remote Access, Wi-Fi and Alexa Enabled, Easy Installation

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Availability: In Stock.
Fulfilled by Elm & Vine
Arrives Nov 18 – Nov 22
Order within 13 hours and 50 minutes
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Description

Product Overview Lennox S40 Smart Thermostat, Touchscreen, Communicating, WiFi, Programmable, 3 Heat/2 Cool The S40 Smart Thermostat recognizes and connects to all Lennox communicating products to automatically configure and control the heating/cooling system (based on user-specified settings) for the highest level of comfort, performance and efficiency. S40 Smart Thermostat also recognizes model and serial number information for Lennox digitally communicating products to simplify system setup. Learn more about the S40 Smart Thermostat below or visit the S40 resource hub for all your dealer needs. 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 and Wireless Extender Advanced digital controls in specific heating and cooling units and the PureAir S Air Purification System communicate information about various operating parameters to the thermostat to constantly maintain the most efficient operating conditions possible Additional conventional (non-communicating) indoor air quality comfort products (Healthy Climate Humidifiers, Humiditrol Enhanced Dehumidification Accessory, Healthy Climate HRV/ERV Heat/Energy Recovery Ventilators, Fresh Air Damper, Healthy Climate Germicidal Lights) can be added to the system for a complete total- comfort system Conventional HVAC systems (non-communicating) can be controlled by the S40 Smart Thermostat with the addition of the optional Equipment Interface Module (EIM) Optional Smart Zoning System (iHarmony, for specific HVAC systems) allows whole-home zoning (up to 4 zones) with complete control from the S40 Smart Thermostat and individual In-Zone Thermostats A simple easy-to-use touchscreen allows complete system configuration. Scheduled maintenance alerts, system warnings and troubleshooting are also displayed on thermostat screen Up to four separate schedules are available plus Schedule IQ One-Touch Away Mode - a quick and easy way to set the cooling and heating setpoints while away Smart Away - Schedule IQ uses geo-fencing technology to determine when the homeowner is within a predetermined distance from the home to operate the system when leaving, away and arriving Weather-On-Demand - live up-to-date weather data and seven-day forecasts Easy to read 7 in. high- definition color display (measured diagonally) New Lennox Smart Technician app allows for quick and easy install of S40 Smart Thermostat and the new smart accessories Installer setup screens allow quick and simple system configuration without a manual Installer can also run tests on complete system or individual components for easy maintenance and troubleshooting Service Dashboard features online real-time monitoring of installed smart digitally enabled systems Uses 4-wire standard thermostat wiring. We highly recommend using 18 - 22AWG shielded thermostat cable for communications terminals (I+ and I-) which will help eliminate any noise interference. Note: The Lennox S40 Smart Thermostat with Equipment Interface Module (22X18) will work with most 24VAC furnaces, air conditioners, air handlers and heat pumps (up to 3 stages of heat and 2 stages of cooling), EXCEPT IT WILL NOT WORK with any brand of communicating HVAC equipment other than LENNOX.

Brand: Lennox


Model Name: S40


Special Feature: Programmable


Color: Black


Brand: Lennox


Model Name: S40


Special Feature: Programmable


Color: Black


Temperature Control Type: Automatic


Connectivity Technology: Wi-Fi


Included Components: Smart Room Sensor, Smart Air Quality Monitor, Wireless Extender, Lennox Smart Technician app, Equipment Interface Module (EIM), In-Zone Thermostats


Power Source: Electric Power Source


Voltage: 22 Volts


Shape: Rectangular


Display Type: touchscreen


Finish Type: Glossy


Screen Size: 7 Inches


Control Type: Touch


Control Method: App, Voice


Connectivity Protocol: Wi-Fi


Mounting Type: Wall Mount


Style: Modern


Backlight: Yes


Manufacturer: Lennox


Package Dimensions: 11.5 x 10.16 x 2.91 inches


Item Weight: 1.68 pounds


Item model number: 22V24


Date First Available: June 29, 2023


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Nov 18 – Nov 22

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Similar Products

Top Amazon Reviews

    • if you have to replace your Lennox thermostat, this one works
If you are like so many others who invested in a new Lennox HVAC with an iComfort thermostat that stopped responding once the warranty is out, you will need to upgrade to the current version of thermostat. I had purchased a Nest only to find out that Lennox has a proprietary system that only works (well) with their own very expensive proprietary thermostat. I had a service person come out to replace the dead unit only to be told it would be over $2K for him to replace it. However, he was able to tell me which thermostat I needed to buy and gave me basic instructions if I chose to install it myself. Shopping on Amazon, there are several vendors selling this thermostat and I chose this one with a price at almost half of all the rest. I watched a couple of videos on how to install and chose to save money and do it myself. I took pictures of the wiring and followed the instructions. The only hiccups I had were getting the thermostat to connect to the mobile app and wondering what to enter for a dealer code/phone number. There are a lot of features on this thermostat. You can set auto high and low temps depending on the time of day. The mobile app will keep trying to reset the high temp to 78 or 84 and going back and forth to the screen, I was finally able to convince it that I really did want my daytime temp to be 72 and night time temp to be 68. This house is never empty and there is no thermostat on the second floor. It gets very warm working up there. You can set the device to show the actual temp inside and outside as well as the "feels like" temp. You can set the default screen to a photo if you like. Overall, it appears to be working after less than an hour of set up. I would drop stars for the price since this is way over priced compared to other thermostats and I really dislike that Lennox produced such a poor quality thermostat that had to be replaced with their newer version at an exorbitant price. ... show more
Reviewed in the United States on April 3, 2025 by M. Schaefer
    • Review of swapping in the latest S40 for defective Legacy Icomfort Wifi "communicating" thermostats
I was replacing a previous Icomfort Wifi "communicating" thermostat (circa 2016) which had glitchy wifi and eventually the screen died. I Iost both local and remote control capability. The S40 turned out to be the latest compatible model that would drop into the existing t-stat wiring without having to touch any wiring over at the furnace. non-lennox smart thermostats (such as Nest, honeywell, etc), will not work as a replacement without also re-wiring over on the furnace. I wanted to avoid touching the wiring on the furnace. a quote thru an authorized lennox installer was north of $1700 (parts and labor) for me. purchasing the thermostat off Amazon was considerably cheaper and the installation was straightforward. there are some videos online which are good references. The setup I have is a lennox Elite EL296 (gas) furnace with a single stage Lennox Elite A/C and lennox healthy climate bypass humidifier. Of these three pieces, only the EL296 furnace is smart (2-stage heating, variable speed fan). the A/C is single stage and is an "on" or "off" control....the bypass humidifer was also "on" or "off". according to the S40 box, it has labelling that states it is compatible with the Signature, Elite, and Merit series furnaces. you don't have to touch the wiring on the furnace side, but if you were to open the furnace front cover and remove 2 screws to open the service door, you would see the thermostat wiring connected to terminals R, I+, I-, C. the A/C and the bypass humidifier are simple 2-wire connections into other ports on the furnace ...no communication happens with the A/C or humidifier in my setup.....the thermostat will communicate to the furnace to turn these items on or off. installation notes: -very important to turn off all power to the furnace before re-wiring the new thermostat. you don't want any surges to damage your new and expensive thermostat. Use the emergency electrical shutoff switch....if that is not accessible, turn off the power at the circuit breaker -the system uses 4 wires. in my case, I have 5 wires and the previous installer had tied 2 wires together into the "C" port. the same 2 wires were connected to the "C" port at the furnace side. note the color of each wire and where it goes....(R, I+, I-, C).....you'll connect to the same terminals on the new thermostat. -after re-wiring, mounting the backplate to the wall, and securing the thermostat to the backplate....turn on the power. thermostat should boot up with a Lennox logo. -follow the directions on the front panel. you can choose to setup using a "lennox technician app" or use the touchscreen on the S40. I opted for the front panel. -after accepting all terms and conditions/privacy/etc.....follow the prompts. when asked to enter dealer ID or phone numer, just skip that screen. Thermostat will auto-detect equipment. in my case, it detected the main furnace model/serial #, plus a single stage A/C and humidifier. NOTE: on this screen, press the A/C setting which will bring up a window which can allow you to adjust the A/C capacity. in my case, I googled the model # of my A/C and it stated it was 2.5ton...another bit of googling converted the tonnage to 30kBTU...so I set the capacity at 30kBTU. this is probably the most sophisticated setting to deal with (IMO) -you will finally get to a screen to run thru tests. go ahead and select all and conduct the tests to check that the fan runs, the heat runs (stage 1 and stage 2 in my case), A/C runs, and humidifier runs. -after testing, you can exit that menu. system should be idle (off).....then go into settings on the S40 to turn on your preferred schedule (summer, winter, spring/fall, custom, Smart). you can then edit the temperatures and timings to your preferences. -lastly, it pays to install the lennox home app and then pair the app and thermostat so that you can have full remote control. it will also allow control via Alexa....and you can enable options such as Geofencing, so the system will setback temperatures based on your GPS data...by default geofencing is turned off. -I took my time, so installation (mounting to wall, re-wiring, and software setup) was probably 30-40min -the S40 uses the new Lennox Home app.....this is different than the legacy Icomfort Wifi App for the older thermostat. ... show more
Reviewed in the United States on September 1, 2025 by VSA
    • Works fine with factory rep install, that way we get the warranty, which is 10 years
Review Image by D. E. D. E.
Review Image by D. E. D. E.
We had our air-conditioning company install this, so that we have the warranty, which is 10 years on it through the company. They charged $530 for the install which is outrageous but still much less than if we bought both the thermostat and the install through the company as that would’ve been over $1800 plus installation. We dislike that the two stage system we have is a proprietary system that requires this thermostat in order to operate correctly. We cannot just put in any thermostat. Buyer beware on the two stage systems!!! we do, however, like this thermostat even though it’s pricey! The original model was really poor because you had to have Wi-Fi to get the time in order to use the programming settings. This one, the time is built in on the chip and you don’t have to have the Wi-Fi to make the programs work. I’m not really keen on the Wi-Fi but we do have it hooked up and all is working well. We just installed it today because it took a while to get the rep out for that. Additional comment: we are needing to set all our temperatures higher on our AC than our previous thermostat. Seems this senses temperatures differently. I do not see an offset available on the program to use a referee ‘real’ temperature. FYI ... show more
Reviewed in the United States on June 25, 2025 by D. E. D. E.

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