If you didn’t know better, you might think that an Ecobee smart thermostat is magical. Wherever you are in your home stays warm. You check out unused rooms and they are colder, to save money and energy. They heat up when you want them to and, apart from your initial programming, it all just works. But you might be curious, how do the Ecobee sensors actually work?

How the Ecobee Sensors Work

When your HVAC professional installed your Ecobee smart thermostat they didn’t just install one device. They installed a sensor for each zone in your home. Perhaps your living room and kitchen are one zone and the bedrooms are another, etc. As the smart thermostat has a separate sensor for each room, it can keep track of separate temperatures and heat and cool each space accordingly, so long as you have a heating system that allows this (like a ductless mini split system).

Even if you don’t have a ductless mini split system, the feedback from the Ecobee sensors can be beneficial. If you know the temperature in different spaces, you can open and close air vents to direct hot air to where it is needed most.

Unlike other thermostats, the Ecobee can use its multiple sensors to adjust for cold and hot spots in the house. So, if Ecobee detects that you’re near a cold spot, and it’s much colder than the rest of the house, it can turn on the furnace or your other heating system to heat that cold spot.

How Does the Sensor Know If I’m in the Room?

You may also notice that if you spend time in a room outside of your usual schedule, like you are home sick when you’d typically be at work, the Ecobee smart thermostat knows and it turns on the heat. This system is called “Smart Home” and “Follow Me.” The smart thermostat keeps the room comfortable for as long as you’re in it, but it doesn’t waste energy by heating this unused room once you’re gone. So, how does the sensor know if you’re in the room?

The Ecobee sensors collect the infrared heat that everyone’s body emits. It’s like night vision goggles, so the Ecobee knows if you’re sleeping in your bedroom or if you’re in the living room watching a movie with the lights off. In fact, the more time you spend near one sensor, the more important that sensor is to the Ecobee as it calculates the comfort of your home.

How to Ensure the Sensors Work Best

There are a few things you need to consider to ensure you’re getting the most out of the Ecobee sensors. First is where you install them on the wall or in a room. They should be 5 feet high and away from any obstructions that may block heat or add heat. So, don’t place them behind a dresser or near your stove. Also place them within 45 feet of anything you want them to measure—45 feet is their maximum range.

Then, you should consider how many sensors you need and where to put them. It’s best to discuss this with your HVAC professional, who can attune the system to your home and lifestyle.