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Make any home an Ecobee Smart Thermostat home with the Power Extender Kit—an easy and cost-effective solution for homes without a C or common wire.

If you’re lacking a C wire and have at least four wires at your thermostat to work with, the Power Extender Kit (PEK), included with your smart thermostat, can be installed at your furnace control board. This allows you to create a C wire using the existing thermostat wiring by combining the functionality of the Y and G into one wire.