In this video we teach you how to identify a common wire also known as a c wire and what it is for when installing a smart thermostat.
Common Wire Adapter: https://amzn.to/3ysXAAK

How To Identify A Thermostat Common Wire:
1. Turn off the power to your existing HVAC system
2. Remove the existing thermostat from the wall.
3. Inspect the existing wiring to see if you have a c wire also known as a common wire. If you have a common wire it will be connected in the C wire terminal of your existing thermostat.

It's important to note that even if you don't have an C wire currently wired to your existing thermostat you may still be able to wire up a smart thermostat that requires a C wire. There are several options.

1. Check for extra wires
Check your existing thermsotat wiring for extra wires. Sometimes there is an unused wire in the thermostat bundle that can be used as a C wire and wired up to the new thermostat and it will also need to be wired up to the existing HVAC system control board.

2. Run a new common wire
You can run a new C wire from your thermostat to your HVAC system.

3. Use your G wire as a C wire ( Common Wire)
You can use your G wire which is the independent fan control as a C wire. You just rewire the g Wire to the C terminal on both the thermostat and at the HVAC system control board and then you have a new common wire. The only downside to this method is that you no longer have independent fan control.

4. Install A Common Wire Adapter
You can install a common wire adapter like this: https://amzn.to/3ysXAAK