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We think the Google Nest is a powerful entry-level smart thermostat, which makes it our top pick overall.
Smart thermostats are more than circular dials that act as control panels for heating and air conditioning. They can also help you lower energy bills and reduce carbon emissions.
Smart thermostats connect to the Internet – usually via a Wi-Fi chip – or connect to a separate hub. It can feature remote control and app-based scheduling options, weather alerts, and even advanced algorithms that learn heating and cooling preferences and patterns. Many smart thermostats connect to voice assistants like Alexa and include geolocation options that use your mobile phone to determine when you’re nearby. Some even have screens that light up when you walk in close proximity so there’s no more tripping around in the dark to manually adjust the temperature setting.
Here are some of the best smart thermostats on the market, followed by tips on how to choose one for your home.
If you’re looking to enter the smart thermostat market on a budget but without skimping on features, Google’s original Nest is a great choice. If you live in a home without a common wire but still want to try a smart thermostat, Google’s Nest E will bring your home and HVAC system into the future.
What to look for in a Smart Thermostat
All smart thermostats share a similar goal: to save money on your energy bills. But they can do more than just control the temperature in your home. Here are some of the key features to consider when shopping for a smart thermostat that goes beyond price, dimensions, and Energy-Star certification.
Check the voltage on the HVAC system and make sure the smart thermostat option you are purchasing is compatible. Most smart thermostats come with 24, 110 or 240 volts.
Voice assistant compatibility
If you use Google Home, Amazon, Alexa, or Apple HomeKit, choosing a smart thermostat that integrates with these smart assistants might be a smart choice.
C-wire or without C . wire
A common wire (C-Wire) runs from a low voltage (24V) heating system to a heating system to provide continuous power for your smart thermostat. Many modern heating and cooling systems have C wires that ensure compatibility with your smart thermostat. But, if you don’t have an old HVAC system or you don’t have a low voltage system, look for a smart thermostat that doesn’t require a C wire to operate or has other ways of connection.
Remote adjustments and alerts
Many smart thermostats allow you to use a phone app, voice assistant, device, or schedule to set the temperature while you’re away from home. Some smart thermostats allow you to set alerts to inform you of temperature changes that might affect other parts of your home, such as freeze warnings that could cause pipes to burst.
When it comes to thermostat displays, size and color may be important so you can better use the features or override the settings. You may also want to add automatic sensors that control the brightness of the display when you’re within range of the thermostat’s display.
This feature coordinates with the smartphone app and allows you to set electronic boundaries that feel when you’re at home, not home, or when you’re near your home. Some may even allow you to set limits for heating or cooling individual rooms.
Frequently Asked Questions
How do smart thermostats help save energy?
Smart thermostats are designed to learn about your behaviors, collect data about your energy use, and have sensors that monitor when you’re at home or away. All of these features allow them to know when to automatically adjust heating and cooling levels to help reduce energy consumption.
Do smart thermostats require batteries?
Because batteries provide reliable and steady power, even when the power is out, many smart thermostat models use batteries. This can be anything from AA and AAA to lithium-ion options. When choosing a smart thermostat, look for one that uses a rechargeable battery or a battery with a mAh rating, so you won’t need to replace it often. Choosing a model that also connects to a C wire is a good option if the batteries are running out.
Do you need to hire an electrician to install a smart thermostat?
Many smart thermostat manufacturers claim that their products are easy to install without the help of an electrician. However, unless you’re familiar with electrical wiring, you may want to get help from a professional – especially if you don’t have a C wire.
Why trust Treehugger?
This article was written by Heidi Wachter, who has spent a decade researching and writing about ways to reduce her environmental impact.
To make our list of picks, I researched customer reviews, third parties, and smart tech experts to find the best smart thermostat options. I looked at the energy-saving features, design, and price point of each smart thermostat. Some smart thermostats have also been tested by Treehugger writers in their homes.