ecobee or Nest? How to Choose a Smart Thermostat in Canada

A smart thermostat lets you set a heating schedule and change the temperature from your phone. Natural Resources Canada says space heating and cooling represents almost two thirds of your home energy use, so the thermostat is a good place to start. Here are four top-selling models, and the one check to make before you buy: whether it fits your heating system.

Which smart thermostat works with your heating system?

This is the check that matters most. The ecobee descriptions say their thermostats work with most 24 VAC equipment, and the Essential lists gas, oil, electric, dual fuel, forced air, heat pump and boiler systems. The Essential description says a home without a C-wire can use the Power Extender Kit, sold separately. The Premium includes one.

Electric baseboard heaters are different. The Mysa description says its thermostat is for 120V or 240V line voltage heaters and will not work on 24V furnaces or central heat pumps. The ecobee and Mysa descriptions both point you to the maker’s compatibility checker, so use it before you order. The Mysa description also says to turn the power off at the breaker, and to hire an electrician where code requires it or if you are not comfortable with high-voltage wiring.

How does a smart thermostat save energy?

Natural Resources Canada says ENERGY STAR certified smart thermostats learn your temperature preferences and set a schedule that moves to energy-saving temperatures when you are asleep or away. It says their savings are based on field data from over one thousand homes over an entire year.

The saving comes from the lower temperature. In Keeping the Heat In, Natural Resources Canada says a drop of 1°C over an eight-hour period can save about 2 percent on your heating energy consumption, and that turning the temperature down is worthwhile if you will be away for more than three or four hours. On its smart thermostat page, it says a good guide is to program 17°C when you are sleeping or not at home, and 20°C when you are awake and at home. Keeping the Heat In adds that it is best not to go below 17°C, because of the risk of moisture build-up in the exterior walls.

What should you look for in a smart thermostat?

• Your heating system. Furnace, boiler or heat pump on 24 volts: an ecobee or a Nest. Electric baseboard: the Mysa. Use the maker’s compatibility checker before you order.
• An ENERGY STAR mark. Natural Resources Canada says ENERGY STAR certified thermostats have been independently certified, based on actual field data, to deliver energy savings. The ecobee Essential and Premium descriptions say ENERGY STAR certified. For other models, Natural Resources Canada points to the ENERGY STAR Product Finder.
• Wiring. The Essential description says homes without a C-wire can use the Power Extender Kit, sold separately. The Premium description lists it as included.
• Smart home and voice control. The Essential description lists Apple HomeKit, Google Assistant and Alexa. The Premium has Siri or Alexa built in. The Nest description says you can control it from the Google Home app or by asking Google.
• A room sensor. The Premium comes with a SmartSensor. The Essential description says a SmartSensor 2 pack is sold separately.
• Warranty. The Premium description lists a 3-year warranty, and the Mysa description lists 5 years on units sold by Mysa.
• Rebates. Natural Resources Canada says utilities or efficiency programs in your area may offer rebates on ENERGY STAR certified smart thermostats. Ask yours before you buy.

Common questions

Is a smart thermostat different from a programmable one? Natural Resources Canada says a basic programmable thermostat provides a clock timer and at least two setback and reset periods a day. It says ENERGY STAR certified smart thermostats go further: they learn your temperature preferences, give you home energy use data to track, and let you control heating and cooling from your phone.

How much will I save? Natural Resources Canada’s smart thermostat pages give no savings percentage for a single home. Its general figure is about 2 percent for a 1°C drop held over eight hours. Your result depends on your home, your heating system and your settings.

Can I install one myself? The Essential description says easy DIY install, and the Nest description says it is designed so you can install it yourself, usually in 30 minutes or less. The Mysa description is more cautious: turn the power off at the breaker, and hire an electrician where code requires it or if you are not comfortable with high-voltage wiring.

Does a smart thermostat work with a heat pump? The ecobee Essential description lists heat pump (2H/1C) systems among those it works with. The Mysa description says its thermostat will not work on central heat pumps. Thinking about the heat pump itself? See our ductless mini-split heat pump guide.

Before you buy

• Find out what heats your home: furnace, boiler, heat pump or electric baseboard.
• Run the maker’s compatibility checker, and check whether you have a C-wire.
• Look for an ENERGY STAR mark, and ask your utility about rebates.
• Decide whether you want a room sensor.
• Cold house? See our draft-proofing guide and our space heater guide.

Sources: Natural Resources Canada, Smart thermostats (ENERGY STAR certified products); Natural Resources Canada, Smart thermostats infographic; Natural Resources Canada, Keeping the Heat In, Chapter 9: Operating your house. Product details come from the Amazon descriptions of the four thermostats, so check the current description before you order.