Smart thermostats do more than just automate a fixed heating and cooling program. These smart smart devices for apps allow you to adjust the thermostat on your smartphone, whether you're on the couch, grocery store or on vacation - wherever your smartphone is connected to a cellular network or Wi-Fi. Many of these devices also work with Alexa, Google Assistant and Siri now giving you yet another way to adjust your thermostat settings with remote access.

Some smart thermostat systems also use smart features such as a motion sensor to determine if you are at home or away and automatically change the temperature - both heating and cooling - for you. Other systems rely on geofencing. : Once you get a certain distance from your home, they automatically switch to distance mode and then back to home mode upon return. Then there are functions such as remote sensors, a power extension kit, thermostats that work with existing infrastructures (ie, compatible with Apple HomeKit) and, of course, thermostats that measure energy consumption so that your home can make me more comfortable. energy efficient.

Even better, these options offer much more than a programmable thermostat - you want a learning thermostat that will improve your temperature control just as much as you like it.

To accompany these modern features, many connected heating and cooling systems have innovative designs. This a rounded shape on a responsive touch screen, the thermostats look much more than they did.

Let's explore the model of options available by model. We will highlight what makes each model stand out from the others and, finally, choose a general winner of the best smart thermostat in the package. Here is a list of recently tested smart thermostats:

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The new Ecobee thermostat is part of the Alexa speaker

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Chris Monroe / CNET

Honeywell Lyric T5 costs $ 150, which makes it our choice for the best smart thermostat choice for those on a budget. I know this is not accurate accessible. But it's a solid price for a Wi-Fi thermostat. Many models, including the Nest Learning thermostat and Ecobee4, cost $ 249. This makes the T5 a great "budget" option that works with Amazon Alexa, Google Assistant and Siri (via AppleKomeKit).

Read our review of the Honeywell Lyric T5 Wi-Fi thermostat.

Chris Monroe / CNET

Honeywell Home T9 is a $ 200 smart thermostat from Resideo. T9 works with Alexa and Google Assistant and offers reliable performance and a robust application. Also, the device is equipped with humidity, proximity and temperature sensors, making it the smartest accessory for sensors. The Nest sensor only offers ambient temperature reading, while the Ecobee sensor only has temperature and proximity sensing capabilities.

Read our review of the Resideo Honeywell Home T9 smart thermostat.

Chris Monroe / CNET

Ecobee SmartThermostat comes with built-in Amazon Alexa. Ask the speaker for temperature, current weather forecast, tell a joke - and adjust the air conditioning of your smart thermostat, all without the need for a separate Alexa speaker. This programmable Wi-Fi thermostat also offers mobile app integration with Google Assistant and Siri, so if you have a Google Assistant or HomePod compatible smart speaker, you can control it with Google Assistant and Siri controls.

Read Ecobee SmartThermostat with Voice Control review.

Chris Monroe / CNET

Setting up the Ecobee mobile application is simple and easy to install and navigate. It sounds simple enough, but so many applications make it difficult to find the specific setting or function you are looking for. Not so with the Ecobee smartphone app. And this is important, as the mobile application is one of the main ways to interact with the Wi-Fi thermostat when you are not directly in front of it (apart from using a voice command).

Read Ecobee SmartThermostat with Voice Control review.

Testing a thermostat

Let's talk about testing. Smart thermostats begin with installation. Installations can vary greatly from thermostat to thermostat and between HVAC systems, but there are some basic steps required to install these devices. As always, consult a professional installer if you have questions about the setup process. Here are the general steps:

• Turn off the power at the thermostat at the switch
• Remove the old thermostat
• Install the thermostat base plate with the screws included
• Attach the wires to the wire terminals
• Attach to the front plate
• Turn the power on at the switch

Was installing the thermostat particularly difficult to install? If so, why? Some models require a C wire, for example, which can complicate installation if you do not have one. Not sure what a C wire is? Start here.

From there, I switch to the application. Each smart thermostat has one. I download the application and create an account if I do not already have one. Then I set up the thermostat by following the steps in the application. This usually means connecting to your local Wi-Fi network, giving the thermostat a "Hallway" or "Bedroom" type name, and then you can start using the thermostat.

How well does the app work? Is it easy to navigate to the thermostat settings you need? Is it easy to create a program or activate geofencing? This determines the use score of the thermostat, along with how easy it is to manually control the thermostat hardware.

I'm also testing smart home integration, especially voice systems that can be accessed through voice assistants like Alexa, Google Assistant or Siri. Most connected thermostats have compatibility with at least one voice assistant and some, such as Ecobee3 Lite and Ecobee SmartThermostat, works with all three. Do voice commands flow naturally, as they would in a real conversation? Did the thermostat actually regulate the temperature - heating and cooling - according to your orders?

All of these things determine the overall score of a smart thermostat and how likely I am to recommend it.

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