Warranty & Support
Best Smart Thermostats
Which Is the Best Programmable Thermostat?
Since 2016, we've tested 14 programmable thermostats to determine which have the best features and are easy to use, and we recommend the Nest Learning Thermostat. It analyzes your habits over time and collects other environmental data so it can adapt to your schedule to keep you comfortable and save you money. Some of this thermostat’s best attributes are how easy it is to install and its compatibility with countless smart home products – it connects with more smart devices than any other thermostat on the market.
The ecobee4 has three key advantages over the Nest: It's slightly easier to use, has built-in voice control via Amazon Alexa and the warranty is three years instead of two. However, it still comes in second to Nest because the latter is easier to install and compatible with more smart home accessories.
The ecobee3 lite’s excellent touchscreen interface matches its mobile app, making it easy to learn how to use both devices. It's an Apple HomeKit-certified device, so it connects to iOS devices and the Apple Home app without special software.
In addition, the Emerson Sensi is the best value of the thermostats we tested, and it has stellar temperature control with seven-day scheduling and a humidity sensor. Finally, the Radio Thermostat CT-80 is a good option for most home automation systems because of its optional Z-Wave and ZigBee modules.
How We Chose Thermostats to Test
We set three guidelines as we chose programmable thermostats to test: First, they had to connect to a Wi-Fi network, and by extension, use a smartphone app. Second, they had to be available at retail stores and installable without professional help. Third, they had to connect to at least one other smart home product.
We borrowed some of the thermostats from their manufacturers and purchased others. The companies had no input on our testing practices, and we didn’t share our results or rankings with them prior to publication.
Our Programmable Thermostat Tests
Last year (2016), our testing went well overall, though there were some hiccups, including wiring that wasn't long enough to connect to some of the thermostats and had no C wire. This year (2017), we used a newer HVAC system and testing went smoothly because of the lessons we learned the time before.
We tested 10 thermostats last year, so for practical reasons, we didn't test each one for very long – only about an hour per thermostat to assess features and usability. This is in addition to the many untracked hours we spent researching thermostats since we first started reviewing them in 2012.
In our most recent round of testing, we only looked at three new models, so we kept each one installed for a day. To keep our results consistent, we used the same methodology this year as we did last year.
Ease of Installation
Installation comprised a large part of our testing because we wanted to see if this is a true DIY project. On average, it took about 30 minutes to install each thermostat from beginning to end. We found that thermostats with video tutorials, online compatibility checkers and built-in levels are the easiest to install.
DIY installation isn't difficult when you have a C wire and your pre-existing wiring is long enough to reach the terminals on your new thermostat.
Common Wire (C Wire)
A missing C wire adds a little time to the installation process, but it's vital for powering features like Wi-Fi and always-on displays as well as for extending battery life. The simplest solution is to choose a thermostat that doesn't need one like the Nest Learning Thermostat or the Emerson Sensi. However, some thermostats, such as those by ecobee, have an adaptor kit that adds a C wire to your system.
If your wiring's not long enough, you don't have to jury-rig it like the temporary setup in our first round of tests. In fact, we don't recommend it. Instead, you should replace the wiring with a longer strand, though it can be tough if you haven't fished wire through a wall before. It's best to pay an electrician to do it for you. While they’re at it, have them add a C wire, if you need one.
After we installed each thermostat, we downloaded its mobile app to see what features are available and how intuitive they are to use. In addition to our testing, we researched each thermostat to get a better picture of its long-term performance and overall customer satisfaction.
Each smartphone app can control basic functions such as setting temperatures and schedules. However, the most impressive apps have the same user interface as the thermostat itself – this is one of the best things about the ecobee4, ecobee3 lite and Carrier Cor because it makes using the features easy and intuitive.
Since many thermostats’ automatic features work largely on their own, we didn't extensively test them in the mobile apps, but we observed each thermostat's behavior while it was active to see how it worked.
We ultimately decide on our rankings based on our experiences during testing and the results each thermostat yielded, but we also did exhaustive research about consumer ratings at top online retailers and our competitors’ sites to track problems we might have otherwise missed. In total, we compared our results with 17 retailers and competitors to gauge each thermostat's potential.
One of the latest industry trends is thermostats with remote sensors you can place in different rooms around the house. These sensors track motion and temperature so your system can tailor its activity based on the room you're in, rather than an unoccupied hallway, which is where most homes have their thermostat.
For now, ecobee is the only company that makes remote sensors for its digital thermostats, which gives the ecobee4 and ecobee3 lite distinct advantages in larger homes. While many other manufacturers make thermostats that support remote sensors of some kind, this functionality is mainly available if you use a smart home hub and the sensors it's compatible with.
What to Expect From the Best Thermostats
Before we continue, we should point out there's a small difference between programmable thermostats and their smart peers. Programmable thermostats rely on a schedule you set, with or without a smartphone app. On the other hand, smart thermostats collect data about your home to make it easier to set schedules, or even eliminate the need for you to program a schedule altogether. Here's what you can expect from the best thermostats:
Lower Utility Bills
Instead of setting a single, stable temperature as you do on a traditional thermostat, you can use a programmable thermostat to set a schedule of what your home’s temperature should be at different times of each day. This saves money in both the short and long term by only heating or cooling when it's necessary. All programmable thermostats have schedules, but smart ones make the process of setting them easier in the following ways:
A smart thermostat builds on your schedule by adapting when your plans change. Some, like the Nest Learning Thermostat, auto-schedule by tracking your habits over time to learn your routines; eventually, they may pick up on your schedule and preferences so well that you don’t need to adjust them at all. Other smart thermostats don't try to predict your schedule and instead respond to your activities.
Smart thermostats with auto-scheduling create a foundation for their programming by observing your habits and local weather patterns or by asking you simple questions. This works best when a thermostat has at least one of the following:
Usage reports let you know how much energy you use and give feedback on how you can save even more. The best smart thermostats keep a complete record of your energy use starting the moment you activate them. Beyond reports, some thermostats have icons, like the Nest Leaf, to let you know you're improving.
Motion sensors allow the thermostat to react to events outside of your regular schedule such as if you come home from work early one day. This is an advantage if you don't interact with your thermostat very often. Unlike schedules and geofencing, however, motion sensors can't make your home comfortable before you arrive home.
Geofencing creates a zone around your house and tracks your smartphone's location to activate home or away modes. While it is a useful feature, geofencing isn't as reliable as a schedule or motion sensors. As location services improve on smartphones, this feature will become more useful.
Smart Home Integration
Some Wi-Fi thermostat manufacturers include home automation functionality so their products can link to popular smart home devices. For example, a smart lock can activate your thermostat’s away mode when you lock the door, a security camera can record a video clip when someone adjusts the temperature, and a fitness tracker can adjust the heat while you sleep. If you have a smart home system, make sure the thermostat you want works with it before you make your purchase.
Using a smartphone app, you can control your system remotely, view usage data and set schedules. All are useful in case you forget to set an energy-friendly temperature until well after you've left the house.
Find out if your utility company offers rebates before you buy a new thermostat, as some offer incentives for you to install a programmable one, which can help pay for the upgrade. Your utility company wants you to conserve as much energy as possible, since it allows it to put what you save to use elsewhere.
A Long Service Life
While new smart thermostat models come out every year, you don't need to replace them often. You can expect most units to last 10 to 20 years under normal conditions. We suggest you only replace your smart thermostat when it breaks, when you upgrade HVAC equipment or if the mobile app stops working when a company goes out of business.
Decoding Common Thermostat Features
This is how many degrees above or below the set temperature your home needs to reach before the thermostat activates your HVAC system. Models with narrow temperature swings of less than a half a degree keep your home the most comfortable but run your HVAC system more often, which can wear down equipment and increase your energy bill. A wider swing is more efficient because it allows the temperature to vary more before activating your home’s heater or air conditioner.
Multistage Heating & Cooling
The thermostat can activate heating and cooling incrementally instead of just turning the system on or off. If one stage isn't powerful enough to adequately cool or heat your home, a stronger stage activates to reach the desired temperature. By only using higher blower speeds when necessary, the system saves energy.
Knowing the weather conditions near your home can help you save energy. For example, you can use this information on especially hot days to set the A/C warmer than normal or turn down the heat on mild winter days. Some thermostats, like the Nest Learning Thermostat, gather this data and use it in tandem with auto-scheduling.
The thermostat can run your air conditioner's fan to circulate the air in your home, which helps eliminate uncomfortable hot and cold spots. Some thermostats can also run the fan briefly after the compressor turns off, which uses leftover cold air in your system that would normally go to waste.
These reminders tell you when to perform basic maintenance like replacing air filters. Some thermostats can also send you an alert when there's a problem with your HVAC equipment.
The best programmable thermostats come with warranties of two or three years. However, some manufacturers provide a longer warranty if you have a professional do the installation. For example, the Carrier Cor has a five-year warranty if it’s professionally installed but only a three-year warranty if you install it yourself.
The best wireless thermostats come with complete customer service, including support reps who can be reached over social media, email, phone and live chat. Because social media support requests are so public, they add a layer of accountability that private communications, such as phone calls, emails and chats, often don't. For example, Twitter is one of the most effective ways to get help with your thermostat because responses are quick and often direct you to the most effective solution.