Emerson Common Wire Kit

Most Wi-Fi thermostats have enhanced features such as Wi-Fi radios and LED color screens that require the unit be powered at all times. Thermostats can get this constant power through a common wire (c-wire). If you do not have a c-wire at your thermostat, the Emerson Thermostat Common Wire Kit allows you to reconfigure your existing wires without needing to run a new wire throughout your home.