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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.
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Arrives Jun 4 – Jun 6
Order within 1 hour and 44 minutes
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Features

  • To provide worry-free 10 year warranty against manufacturing defects or defects. To maintain warranty validity, it is necessary to hire a certified HVAC loader for proper installation. Failure to use a professional HVAC loader may render the warranty void. If the thermostat is not professionally installed, the item cannot be returned or returned. How to register for warranty, instruction included in the box.
  • It has a 7 inch high resolution color screen for easy readability. User-friendly touchscreen for easy system configuration and maintenance alerts. Using geographical fencing technology, multiple programs offer One-Touch Away Mode and Smart Away feature.
  • Compatible with 4-wire standard thermostat cables, use protected thermostat cable to prevent noise interference. Works with most 24VAC ovens, air conditioners, air conditioning processors and heat pump (up to 3-stage heat and 2 cooling stages) outside of the communication of HVAC equipment outside LENNOX.
  • Compatible with traditional HVAC systems with optional Equipment Interface Module (EIM) for control. The Smart Zoom System (iHarmony) allows the entire home improvement with full control from the S40 Smart Thermostat.
  • On-Demand Weather provides live weather data and seven day forecasts. Quickly set up and configure with the Lennox Smart app. Installer setup displays allow quick system configuration without manuals.
  • Test on the entire system or individual components for maintenance and troubleshooting. Service Panel allows real-time monitoring of installed smart systems.
  • Improve temperature and air quality control with advanced accessories such as Smart Room Sensor, Smart Air Quality Monitor and Wireless Expander. Taking insights from digital controls and through the PureAi S Air Purification System to maintain efficient working conditions.

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


Additional Features: Programmable


Specific Uses For Product: Air Conditioner, Heat Pump


Temperature Control Type: Automatic


Connectivity Technology: Wi-Fi


Power Source: Electric Power Source


Voltage: 22 Volts


Display Type: touchscreen


Screen Size: 7 Inches


Control Type: Touch


Control Method: App, Voice


Connectivity Protocol: Wi-Fi


Mounting Type: Wall Mount


Backlight: Yes


Smart Home Compatibility: Smart Home Compatible


Brand Name: Lennox


Model Name: S40


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


Model Number: 22V24


Manufacturer Part Number: 22V24


Unit Count: 1.0 Count


Color: Black


Shape: Rectangular


Product Style: Modern


Material Type: Glass, Plastic


Finish Types: Glossy


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Jun 4 – Jun 6

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews

    • Saved over $1000
Thermostat works great! The HVAC company wanted to charge $1700 dollars. I bought it for $640. Installed and programmed it in about 30 minutes. It comes with good instructions. I did read some reviews and instructions on Amazon. I also watched a lot of YouTube videos, probably too many. *The 10 year warranty that comes with the thermostat is only valid if installed by a licensed contractor. My company wanted $145 dollars to install this unit for me. Which is not too much but I just took a gamble and installed myself. I highly recommend buying. ... show more
Reviewed in the United States on April 8, 2026 by js 432
    • Easy replacement of Lennox iComfort WIFI 10F81 to this model
Replaced Lennox iComfort WIFI 10F81 - was 10 + yrs old & screen went blank. Have to replace back plate. Wires were different color than instructions so replaced to match according to existing wiring "R 1+ 1- C" as directed by our "on call HVAC guy" - did not have to have him out. It automatically hooked itself up & then I ran through 'set up'. Fired right up! Great price - paid extra to get next day - arrived! ... show more
Reviewed in the United States on April 3, 2026 by Hunaangel
    • 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
    • Yes, this is the replacement to the older screens and it's easy to install.
Yep, I had the older Lennox touchscreen unit...sorry, I forget the old model number...that experienced the dreaded dead screen. Like many other users, I was dismayed to see the replacement model recommended for professional install, raising the cost beyond kind words. Well, install is pretty easy. With the right instructions, it took me five minutes with a small screwdriver. No biggie. This thermostat works to control my lennox HVAC. The screen has some nasty lag, so it's actually easier to use the app on the phone sometimes. There are some flashy features, like the ability to use your own photos for the background and smooth app integration. I can even set it to give me a monthly summary of system usage, which is not important, but it's kinda fun. It has easy to check weather forecasts built in (as though we walk to the thermostat to check the forecast). It's also got highly programmable settings for single/multi zone and times of day that's all easy to customize. Most importantly, if you're looking for the current replacement to the touchscreen Lennox thermostats from 5-10 years ago, this was the right unit for me. Installing it was easy for me, no technician required, since it uses the same wires as my old thermostat required. Other brand smart-thermostats seem to require other wiring. So, even though the unit is pricey, it was the right way to fix my system myself, and avoid costlier technicians doing what I can with a single screwdriver. In summary, it works, it's easy to install for Lennox HVAC systems, and it has a few features. If you're checking out this model because it's the current replacement for your older Lennox thermostat, yes choose this and install it yourself. ... show more
Reviewed in the United States on August 20, 2024 by M. Acker

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