Smart Thermostat Buyer's Guide

What Makes Smart Thermostats So Smart?

Smart thermostats are loaded with features that make it easy to save energy and money. They eliminate confusing programming, adapt to your preferred heating and cooling schedule, can be controlled from anywhere using a smart phone, and so much more...

System Compatibility (what do need to know?)

Low voltage heating/cooling systems are the most common, requiring 24-volt power. All of the Wi-Fi thermostats offer here are compatible with low-voltage systems.

Direct line voltage systems use 110 VAC to 240 VAC power. This would include electric resistant baseboard heating systems or radiant heating. The thermostats offered here are not suitable for use with direct line voltage heating.

Millivolt systems are often natural gas wall or floor heaters that do not use any electricity. Only one of the thermostats is millivolt compatible.

Some thermostats need 24-volt power to be provided through a common-wire ("C-wire"). In some cases, a "C" wire is required, and in other cases it is only recommended. If a wire is attached to the "C" terminal behind the thermostat, you have a C-wire already installed. If a C-wire is not present, one can be installed, but professional installation is recommended.

Conventional one stage heating and cooling systems are either "on" or "off". All these Wi-Fi thermostats will work well with these systems.

Conventional two-stage systems have both low and high speeds. To tell if you have a 2-stage system, if the wiring behind your thermostat is attached to "y1" and "y2" terminals, you have a one-stage system. If the wiring is attached to "w1" and "w2" terminals, you have a multi-stage system. Most Wi-Fi enabled thermostats are compatible with two-stage systems.

Compatibility with heat pump systems that have auxiliary heat will vary by model.

Whole House Systems

Sometimes dehumidifiers, humidifiers, and energy or heat recovery ventilation systems that must also be controlled by the thermostat. The ability of thermostats to control these other systems will vary by brand and model. Often professional installation is recommended in these situations.

If unsure about compatibility, online compatibility checkers are available on many of the product pages, or consult with a qualified HVAC professional.

Smart Thermostat Features

Many of our smart thermostats share the following features. You can learn more about the specifics of each thermostat in the chart below or on the associated product page.

Learning Ability: Thermostats with learning ability will automatically adjust settings based on your personal preferences and schedule, resulting in increased savings over time.
Occupancy Sensing: Thermostats with occupancy sensing technology go into an energy-saving mode when no one is present, so you never have to worry about turning the thermostat down when you leave. Occupancy sensors may be integrated or separate, depending on the model.
Geofencing: Geofencing uses your connected smartphone to determine your location and make thermostat adjustments accordingly. When you are away, energy-saving mode is enabled. When you return, your thermostat turns back up.
Smart Sensors: Remote temperature sensors allow the thermostat to determine the temperature in the rooms where the sensors are placed, not just where the thermostat is located. This helps customize comfort in every room. Smart sensors are sold separately, but are included with some models.
App Alerts: When connected to a thermostat's app, you can get helpful reminders and alerts sent to your phone. Get reminded when it's time to replace your furnace filters or get notified when extreme temperatures are sensed, indicating your furnace may be malfunctioning.
Energy Reports: Energy usage reports show you how much energy you've used and teach you how to use less.
ENERGY STAR Certified: ENERGY STAR thermostats have been independently certified to deliver energy savings. These are the smartest of the Wi-Fi thermostats available and include top-of-the-line features to help you manage your energy use.

How Do Smart Thermostats Help Save?

Smart thermostats can help you lower your energy needs, which saves you money and decreases your environmental impact.

Use this table to compare smart thermostat models and features.

	Google Nest Learning	Google Nest Thermostat	ecobee3 lite	ecobee SmartThermostat
MSRP	$249	$129.99	$169	$249
C-Wire Required?
Wi-Fi Enabled	Y	Y	Y	Y
Geofencing	Y	Y	Y	Y
Learns User Habits	Y	Y	Y	Y
Built-in Voice Control				Y
Works w/ Sensors	Y		Y	Y
Sensors Included				Y
Auto-Away	Y	Y	Y	Y
Adjustable Schedule	Y	Y	Y	Y
Maintenance Alerts	Y	Y	Y	Y
Mobile App	Y	Y	Y	Y
Warranty	2 Years	1 Year	3 Years	3 Years
ENERGY STAR Cert.	Y	Y	Y	Y