What Nobody Tells You About Smart Wifi Thermostats

updated May 3, 2019
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Have you made the leap to a smart Wi-Fi thermostat yet? Once you experience the bliss of a pre-warmed house before you get out of bed in the morning, you can never go back. But did you know there is SO much more to the gadgets like Nest, EcoBee, and the rest?

I was maybe too early of an adopter, and bought a pretty standard issue Honeywell Wi-Fi thermostat with no bells or whistles. Hey, at the time, just changing the temperature from my phone was amazing enough. But, if like me, you haven’t looked at the options lately—or haven’t actually made the switch yet—you may be blown away by what they can do now. There are some caveats though, so read on for the good and the bad.

Here are the things nobody tells you about Wi-Fi thermostats.

They play well with others

If you’ve gone full-on smart home, no need to even pick up your phone to crank up the heat—just announce your request into the thin air. According to CNET, Nest, EcoBee, and Honeywell Lyric work with Alexa (in the case of Ecobee4, Alexa Voice Service is built in, meaning you can also listen to music and news from your thermostat). The Ecobee and Honeywell Lyric also works with Apple HomeKit and Google Assistant, while the Nest works with Google, too. Certain models can also be synched to other devices, like smart plugs, light bulbs, and even your door locks.


I’m always trying to manage the heat bill in our big, old drafty Victorian, so we manually (well, on the app) turn down the heat whenever we leave and then try to remember to turn it back up before we get home so we don’t walk into a bone-chilling house. Nest, Ecobee, and Sensi offer energy-saving modes when you go beyond a certain perimeter around your home. Leave the house in the winter and it will turn your heat down automatically. Better still, it goes back to your preferred temp when you come back within a certain radius. Amazing.

They have even more tricks up their sleeve

Yes, Wi-Fi thermostats learn your schedule and reduce energy usage while you’re away, but they can do more. They check the weather—and respond accordingly. Digital Trends reports that the Ecobee4, Nest, and Honeywell’s Lyric use weather forecasts and outdoor temps to work even smarter wizardry. They can regulate indoor humidity, tell a ventilator to bring in more cool air to kick the AC usage down, or puzzle out how much auxiliary heat to use.

No Wi-Fi? No problem (mostly)

If you suffer from the bane of modern existence—sketchy Wi-Fi—you may wonder what happens to that smart thermostat when the connection is out. Turns out, they’re so smart they know how to dumb down. How-to Geek explains that, when the internet connection is lost, they’ll just act as a normal thermostat—the kind you have to get up from the couch to operate. If you’re not at home, that just means you won’t be able to check in on the temp via the app; it will stay set to whatever it was last programmed to.

Except when it is a problem …

This reddit horror story illustrates what happens when a smart thermostat breaks. A user in northern Canada left town with his house in the dead of winter; the system failed, didn’t notify him, and he returned to frozen and burst pipes. Other users weighed in with their own fail stories. The major takeaway from the post and comments: If you’re relying on a smart thermostat and won’t be home, have a failsafe manual thermostat in place.

Don’t forget the special wiring

Consult with the manufacturer to make sure that your chosen thermostat is compatible with your particular heating and cooling system. If you are installing it yourself, and your system doesn’t have a common wire (c-wire), you’ll need to add one before you can hook up your new thermostats. Some brands include adapter kits to make this process easier. If you’re uncomfortable with rewiring your HVAC, hire a professional.

You might need to move

I’ve heard one minor quibble about Wi-Fi thermostats from friends who work from home. If your thermostat doesn’t think you’re in a room (say, if you’re plugging away at your desk for hours without moving), it might decide you’re gone and respond accordingly. A little bit more annoying perhaps, but also maybe just a little added incentive to get up from your desk once in a while.