Installation

Does my Sensi thermostat need a common wire, or "c-wire"?

The need for a common wire, or “c-wire,” depends on which Sensi thermostat model you have and your system type.

The Sensi Wi-Fi Programmable Thermostat works on most combined heating and cooling systems without a c-wire.

The Sensi Smart Thermostat also works on most combined heating and cooling systems without a c-wire, however, will require a c-wire for Apple HomeKit functionality.

The Sensi Touch Smart Thermostat always requires a c-wire.

Reference the master compatibility chart in this article to review c-wire needs.