Review: Lennox icomfort WiFi Thermostat–Sonos For Air Conditioners

“It’s Sonos for air conditioners.” That’s the first thing my wife said when she saw the new Lennox XC21 air conditioner installed in our home in Miami, Florida, after replacing a 10-year old Carrier unit. Not since I installed Sonos in our home in 2006 has a new technology received a 10 out of 10 wife acceptance factor.

Yes, my wife knows the air conditioner is listed as an Energy Star most efficient 2012. And, that it will save us money.  Never before has our 1926 (leaky) house reached 43%-48% indoor humidity, making it more comfortable than ever. Yet, it’s the thermostat. The 7″ color display. The remote access. The one-touch away mode.

icomfort WiFi Thermostat-Home Screen
The Lennox icomfort home screen connected to WiFi, which enables remote access and weather forecasts provided by

We use the thermostat everyday, whether at home or on-the-go, using the Lennox icomfort iPhone app (free). The Lennox XC21 air conditioner system was installed on June 18, 2012 by Engineered Air in Pompano Beach, FL. Through Ken Kiefer at Engineered Air, I was able to purchase an icomfort WiFi thermostat a couple of weeks before it became generally available. I’m glad I did. Thanks, Ken!

Intelligent Thermostats: The Apple Impact

Clearly, thermostats are becoming more intelligent, primarily by connecting them to the web and enabling direct communications with air handlers and outdoor condenser units. Web-enabling thermostats provides an easy way to monitor and adjust temperature settings, set/cancel away settings, program daily temperature programs and view past usage. And, creating apps for mobile devices (iPhone, Android, iPad) allows anywhere access. Direct communications between the thermostat and the air handler and condenser units simplifies diagnostics for technicians, whether I provide error codes to a technician when calling in for service or the error codes are transmitted proactively to my dealer.

Set-up and Configuration

icomfort WiFi Thermostat-WiFi Settings
WiFi settings screen connected to my home network and registered with the Lennox web site. I love the auto firmware upgrade. Not all thermostats auto-update.

Set-up and configuration was a snap. I enabled WiFi on the thermostat, which allowed the thermostat to see my wireless network. I entered the WiFi password on the thermostat and was connected to my wireless router (Apple Airport Extreme 4th Generation). No futzing with firewall settings. It just worked. Like Apple products do.

Then, the thermostat directed me to create an account on Account set-up was simple consisting of 3 steps: My Profile, My System, and My Dealer.

icomfort WiFi Thermostat-Web Setup
The “My System” step during set-up on I’m not sure why they asked for home details, but I entered them anyway.

Set-up was smooth, except my preferred dealer (Engineered Air, LLC) did not appear based on my zip code, even when selecting a 100 mile radius (my dealer is 33 miles away). I typed in my dealer’s zip code (33064) and then their name appeared on the list. Bam. I had my dealer associated with my account.

Things I like:

  • The 7″ screen is gorgeous
  • One-touch for “away” or “cancel away” settings
  • Firmware auto-update (I looked at a Trane system and the Trane Comfort Link II thermostat, which requires downloading firmware updates to a computer and transferring them via SD card to the Trane thermostat)
  • Free remote access (At time of this blog post, the Trane Comfort Link II required a Nexia Home Intelligence account – $8.99 monthly/$99 yearly)

Suggested Improvements:

  • Show outdoor humidity
  • Clicking on the weather icon should show the day’s hourly weather forecast
  • Usage monitoring bar chart (day/week/month). I would also like to plug in my electricity rate to see how much my air conditioner costs to run

iComfort iPhone App

For the first 2 weeks, I couldn’t stop opening the Lennox iComfort iPhone app (1.0.2). I would constantly check the house temperature throughout the day. It was a feeling of power to know that I could control the temperature anywhere I had a cellphone connection. This is great when traveling in case you can’t remember if you turned down the air conditioner before leaving or not.

The iComfort iPhone App is elegantly simple and consists of 3 screens.

icomfort WiFi Thermostat-iPhone App
The 3 main screens of the iComfort iPhone app. I generally leave the app on the temperature (middle) screen, leaving the app running in the background.

Things I Like:

  • It’s simple
  • One-touch for “away” or “cancel away” settings. This is the feature that I use the most.
  • Multiple homes and thermostats can be managed from the iPhone app

Suggested Improvements:

  • Timestamp of last temperature update – I find myself going to the “My Homes” screen and selecting my home to force an update of the temperature screen. Otherwise, you cannot tell if the on-screen temperature is cached or is current.
  • Show outdoor temperature & humidity
  • Geo-Fencing – Once I pass a geo-fence of .5 miles away from my home (user-configurable), I would like the thermostat to automatically set itself for “away”. When I pass within .5 miles of my home, the “away” setting is automatically cancelled.

iComfort iPad App

The iComfort iPad app (1.0.7) was first released in late July 2012. The app largely seems to be a copy of the wall-mounted thermostat, albeit with less functionality. The weather icon is not clickable as it is on the wall-mounted thermostat. Overall, the iPad app feels like a minimum viable product. But it works. It has the basic functionality of the wall-mounted thermostat, but I can see a lot of potential, especially for energy usage monitoring.

icomfort WiFi Thermostat-Home Screen-Cooling
Lennox iComfort iPad app main screen. The weather icon is not clickable, but there are lots of other weather apps for the iPad.

iComfort Web App

The iComfort web app is straight-forward, offering the same ability to change temperature settings, set/cancel “away” mode, and see the weather forecast. It is the easiest way to get system information. For those cases when I don’t have my mobile with me, it’s nice to be able to login to the web app, but I find that I rarely access it. The mobile apps are far more convenient. While fully functional, the web app doesn’t have the same quality of graphical design compared to the thermostat or mobile apps. The fonts are garish and everything has sharp corners.

icomfort WiFi Thermostat-Web Thermostat
Lennox iComfort web app home screen. Definitely less design polish than the thermostat or the iphone/ipad app. Viewed in Google Chrome.


After having used the Lennox iComfort WiFi thermostat for about 45 days, I will never go back to a programmable or conventional thermostat. Not only does my wife love it, I do too. In fact, the functionality of the thermostat has now made it into my top purchase criteria for new air conditioner systems:

  1. System rated as Energy Star most-efficient central air conditioner
  2. Intelligent thermostat functionality
    1. Is remote access free?
    2. Ease of firmware updates
    3. Usage monitoring
  3. Quality of dealer install

Give the Lennox iComfort WiFi thermostat a try, either through a local dealer or buy online (about $350)