C-wire Help Made Simple.

Do I Need a C‑wire?

If you're wondering what a C-wire is or how to look for one, you’ve come to the right place. Our step-by-step videos will guide you through the process and answer all your questions.

Basic c-wire introduction

Learn about the basics of common wire installation by watching this video. You will also be guided on how-to and when-to connect C-wires to thermostats. It also shows three different scenarios to choose which methods works best for you.

Finding and Using an Unused Wire as a C-wire

Sensi Thermostats require a common wire to complete installation. This video will guide you in checking if you have a common wire, or an unused common wire from your previous thermostat that you can use to install your Sensi Thermostat.

Using the G-wire as a C-wire

If you can not find an unused wire or common wire, you can also use for fan wire or G-wire as a common wire. This video serve as a second option in common wire installation.

Installing Common Wire Maker Kit

If there is not an extra unused wire running from the thermostat to the furnace, and using the G-wire as a common wire is not an option, in most cases, installing a Common Wire Maker Kit is the best solution.

In the Box

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