Price: $869.99 - $739.00
(as of Jan 10, 2025 03:37:13 UTC - Details)

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.
Reviewer: Neil
Rating: 5.0 out of 5 stars
Title: 5 minute replacement!
Review: I was quoted almost $1200 for a replacement to my Lenox thermostat, but this bad boy is better than the original, takes 5 mins to install and is way easier to control via the app! If you need a replacement and this one is compatible, buy it!

Reviewer: TR
Rating: 5.0 out of 5 stars
Title: Supports my Lennox variable speed system and saved me money
Review: Bought this with all the mixed reviews. Installed it myself since it is a wire for wire replacement ( many videos/instructions on the internet ) at the thermostat for my old iComfort which lost its screen and was only useable with the limited app. This is not an Ecobee or Nest but has plenty of functionality if you care to learn how to program it.While I wanted to get an Ecobee it was not a smart choice for a Lennox variable speed system since a lot of the Lennox function are not supported. Getting this from a dealer with a warranty would have cost me over double what it did to buy it on Amazon and put it in plus they would have wasted my time upselling service contracts, extended warrantied and all the other BS the authoorized dealers push on consumers.It took me 30 minutes to replace the old iComfort and the S40 has been working like a charm. If it breaks in the next few years, I'll buy a new one and still be financially better off. Is this the perfect thermostat ? Is is the smartest one out there ? Is it value for money spent when an Ecobee or Nest is $200+/- ? No, but if you have a variable speed Lennox with all the whistles and bells this is a smart choice as it will help keep your energy costs in check over the long run and thus pay for itself.The seller shipped it quickly, brand new ( not a return) and it arrived intact and ready to unbox and install.

Reviewer: M. Acker
Rating: 4.0 out of 5 stars
Title: Yes, this is the replacement to the older screens and it's easy to install.
Review: 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.

Reviewer: C M J
Rating: 1.0 out of 5 stars
Title: BEWARE: NO WARRANTY ON THIS THERMOSTAT, PER LENNOX. 20% RESTOCKING FEE IF RETURNED TO SELLER.
Review: PER LENNOX:- This Limited Warranty does not apply to, nor is anywarranty offered by Lennox for, any Equipment orcomponents that have been stolen or have beenordered over the internet, by telephone or otherelectronic means, unless the dealer or licensed HVACinstaller selling the Equipment or components over theinternet, by telephone or other electronic means, isalso the installing contractor.

Reviewer: TMRealtor
Rating: 5.0 out of 5 stars
Title: 10f thermostat replacement
Review: This product worked very well. Set up was not difficult. Seems to even work better than the original unit before that one quit functioning properly. Also the discounted price was expensive but better than I could find anywhere else.

Reviewer: Stephen F.
Rating: 3.0 out of 5 stars
Title: A tormented review
Review: First off, let me start by saying that I will never buy a Lennox system. ever. The house we currently live in came with one that was newer so it was never really a concern to look for a new HVAC system or thermostat. Lennox uses propriatary technology in their systems which basically means you have no choice but to use their thermostats. Normally I wouldn't mind this, but the problem is that they price gouge their theromstats to an unthinkable level. Where you can get a nest thermostat, or really any other thermostat for a very reasonable amount, you're paying 3x as much just to have "Lennox" thermostat. Does their thermostat do anything the others don't? No. Does it to do them better? No, but again, you have virtually no choice in the matter.Now... having said that, my star review is based on the insanely inflated prices of the thermostat and not it's functionality. The thermostat itself actually works well. It's got a lot of built in functionality and the access to the app is nice as well. It can sync up with Google and Amazon devices which is also nice.So would I buy this thermostat again if I have a Lennox system? yes. Do i like it, No. Take my review for what it is, and that's a glowing review on a piece of technology, and a disgust for the company itself.Cheers

Reviewer: Mae Hawkins
Rating: 5.0 out of 5 stars
Title: It works!
Review: Our Thermostat went out this is a replacement. Definitely an upgrade! Took a short time to configure but not too difficult.

Reviewer: Ron Weaver
Rating: 2.0 out of 5 stars
Title: overpriced junk beware of lennox
Review: at least it was cheaper here .