SAVE MONEY: Homeowners save up to 23% annually on heating or cooling costs, plus ecobee pays for itself in under 2 years (compared to a hold of 72 degrees).ROOM SENSORS: Place them in the rooms that matter the most and have the temperature balanced throughout your whole home. Measuring both occupancy and temperature, sensors signal your ecobee Smart Thermostat to automatically switch to the right mode for comfort when you're home or for savings when you're not. One Room Sensor included, 2-pack sold separatelyEASILY INSTALL YOURSELF: It only takes about 30 minutes, thanks to an easy to follow installation guide and an in-app step-by-step walkthrough. Everything you need comes in the box, including a Power Extender Kit for homes with no common wire (C-wire). Compatibility- Gas, oil, electric, dual fuel, Conventional (2H/2C), Heat Pump (4H/2C), Humidifier, Dehumidifier, Ventilator, HRV or ERVCONTROL FROM ANYWHERE: Easily adjust your thermostat from wherever you are using your iOS (iPhone, iPad, Apple Watch) or Android device. The ecobee mobile app is available in the App Store or on Google Play.BUILT-IN ALEXA: Control your thermostat using your voice with built-in Alexa. Ask to play music, hear the news, set a timer, adjust the temperature, and so much more. Wifi connectivity is ieee 802.11 b/g/n at 2.4 GHz. Tip-make sure your HVAC panel is fully closed. Some systems will not turn on if the cover panel has not been closed properly.Voltage Type:Line Voltage