The HVAC system in your home is one of the most significant sources of energy usage. But it can also be a huge source of energy waste if you don’t optimize how you heat and cool your home. The best Alexa thermostats do this for you, learning your heating and cooling preferences and helping you save on energy bills by reducing HVAC use when you’re not at home.
Most modern homes can support a smart thermostat, and installation takes less than 30 minutes in most cases. Some higher-end thermostats use machine learning to look at how you use your thermostat over time, eventually setting themselves up without you needing to do so manually.
We consider smart thermostats a luxury in the smart home and suggest you first build out your smart home with video doorbells, a smart speaker, or smart cameras. But an Alexa thermostat is a great buy if you plan to get serious about connecting your home.
Worried that your energy provider can control your smart thermostat? Read this blog on the subject to learn more.
Frequently Asked Questions
We’ve answered some common questions we hear from readers below on buying and using a smart thermostat. Have a question, contact us and ask!
What is a smart thermostat?
A smart thermostat is an internet-connected device that allows users to control and monitor their home’s heating and cooling system through an app or voice control. Smart thermostats will enable the user to schedule the home’s desired temperature for various times of the day. The thermostat uses geofencing and other smart home devices to detect when you’re home and when you’re not, saving energy.
What makes a smart thermostat “smart”?
A thermostat is “smart” because you can control it through a mobile device or voice using Alexa or Google Assistant. Most smart thermostats learn your heating and cooling preferences over time, making it unnecessary to adjust the thermostat manually. If the user wants to set their temperature, they can do so via the app.
Will my HVAC system work with a smart thermostat?
Smart thermostats require “low voltage” systems (24V) to operate. At a minimum, you’ll need a “C” wire to provide continuous power to the thermostat. The best thing to do is to visit the website of the thermostat you’re thinking of buying and look for a wire reference guide. Remove your current thermostat, and compare the wires to the guide. As a general rule, if you already have a digital thermostat, you’ll likely have the necessary wires; if you have the old rotary-style thermostat, you will likely not. Most radiator-based systems are millivolt systems and are not compatible with smart thermostats.
What is geofencing?
Geofencing allows users to set up their smart thermostat to adjust the home’s temperature when nearby. For example, you could set the thermostat to start cooling the house in the summer when it detects you’re returning home. Some thermostats have this feature built-in, while others require a separate app to be downloaded onto your smartphone.
How much can I save on energy costs by using a smart thermostat?
The Department of Energy estimates that users can save up to 30% on their energy bills using a smart thermostat. The user can program the thermostat to save energy by turning it off when the home is not in use.
What are some drawbacks to using a smart thermostat?
Some users have complained about the cost of installing a smart thermostat. Others have said that the learning curve for some of these devices can be a pain point.
Best Alexa Thermostats
There are quite a few options out there for a smart thermostat. Here are our favorites right now.
Honeywell is a name well-known in thermostats: their gold-colored circular thermostats are a common sight in older homes. While Resideo manufactures the Honeywell Home line, these smart thermostats are as reliable as the old ones, and the T9 is one of the most popular models.
Like the more expensive thermostats, the T9 can detect when you’re home and away. Combined with optional temperature sensors, it can heat and cool your house as efficiently as more expensive models. Everything you need is in the box, and installation isn’t complicated.
Voice Assistants like Amazon Alexa and Siri are becoming ubiquitous, so we’re not surprised that there’s a smart thermostat with both built-in, like the Ecobee SmartThermostat with Voice Control. Alexa is available without additional hardware, while Siri requires a HomePod on your network to work. You can add sensors to detect when a window is open to shut off the HVAC unit automatically, and the included temperature sensor allows you to monitor the temperature in other rooms.
If you’d like to extend voice control into the room where your thermostat is located, this is one way to kill two birds with one stone in your smart home setup.
Think of the ecobee3 lite smart thermostat as the entry-level model in the ecobee line. It doesn’t include the built-in voice assistant capabilities, making it a bit cheaper. We recommend stocking up on the optional accessories, which allow you to use all the features of your ecobee smart thermostat.
Honeywell Home has teamed up with Amazon to introduce the Amazon Smart Thermostat. Alexa handles all the programming for you, and obviously, you control your thermostat using your Alexa speaker. This is a brand new device, so we don’t have much information. However, early reviews are positive, and at just $60, it’s the least expensive smart thermostat on our list.
Mysa is a lesser-known and newer smart thermostat on the market, however, we’re big fans of their minimalist design, which perfectly suits the modern home. The minimalism doesn’t extend to the capability of the Mysa Smart Thermostat, with advanced features including Apple HomeKit, Google Assistant, and Amazon Alexa support, and the ability to schedule the operation of your HVAC system. There are versions available for electric in-floor and baseboard heating.
Other Good WiFi Thermostats
You might call the Google Nest Learning Thermostat the grandaddy of smart thermostats. The design has remained the same through three generations, but the thermostat has improved. While you can program the Nest Learning Thermostat just like any other smart thermostat, it’s better to use your thermostat as you usually would.
Over time, the thermostat learns your heating preferences and adjusts the temperature accordingly. We recommend picking up the optional temperature sensors, allowing your thermostat to work more efficiently. It even knows when you’re at home and when you’re not, shutting off your HVAC system to save money.
Google Nest Thermostat is essentially an updated version of the Nest Thermostat E, which was intended to be a cheaper alternative to the pricey Nest Learning Thermostat. While you can still program heating and cooling schedules, and the Nest Thermostat has the same geofencing capabilities as the Learning Thermostat, you lose the learning capabilities. That might not be that big of a deal for some of us.
Any of our recommendations above for the best smart thermostats are solid, but we recommend the Nest Learning Thermostat as it’s the best overall value, in our opinion. While it’s one of the more expensive smart thermostats out there, it’s also one of the best regarding the “smart” side. They should, too: the Nest Learning Thermostat is one of the original smart thermostats.
Over time, the Nest Learning Thermostat becomes very good at anticipating your heating and cooling needs. After the initial training period, owners tell us that they rarely touch the thermostat. If you don’t need the advanced learning capabilities, choose the Nest Thermostat instead, which helps you save money on your utility bills.
We’ve also heard many great things about the Ecobee Smart Thermostat, especially the version with Alexa built-in.
As we said, competition is fierce between the best smart thermostats on the market, so we’d recommend any of the above smart thermostats if you’re looking. Every device in our recommendations is a solid performer.
Choosing the Best Wifi Thermostat
Smart thermostats are compatible with most HVAC systems except for baseboard heating and older “millivolt” systems. While there are options for baseboard heating smart thermostats, We found no truly smart thermostats for millivolt systems. This is because (as the name suggests) insufficient power is delivered to the thermostat to power the necessary functionality, like Wi-Fi and the display.
If you have the correct HVAC system, a smart thermostat will be invaluable and pay for itself quickly in the energy savings you’ll generate. Some utility companies offer mail-in rebates, usually $50-100, to purchase a smart thermostat — which helps offset their initial high cost even quicker.
The best WiFi thermostats also support your HVAC system’s automatic home/away operation. This is done through integrated sensors on the thermostat itself (all above except the ecobee has this) and/or optional accessory sensors that can be placed throughout your home.
Those accessory sensors will also report to the main thermostat on conditions in other rooms, which will help heat and cool your home more effectively. Most also can talk with other smart thermostats in the home, which are found in large properties and commercial settings where separate thermostats might be desired for more precise control.