Thermostat Center

Reviews and General Information on Programmable Thermostats

The C-Wire Issue

When you read through the reviews I have on my website, you will notice that lots of manufacturers state their thermostats need a common wire in order to work properly. However, just because you don’t have the blue wire mentioned above, that doesn’t mean you can’t use various models.

My research has taken me on quite a journey in this respect, and so far I have come across three options that will help you overcome the common wire issue so many people suffer.

Unused C Wire Terminal

So you’ve decided to install your new thermostat and discover that you have an unused wire but you do need a C wire connection. In this really short video you will learn how to connect an unused wire so it can be used as your C wire, which in a lot of cases has solved the problem of a thermostat not working.

Substituting a G Wire for a C Wire

As you will notice from the information above, your ‘G’ wire connects to the fan (as industry standard) and is green in color. Before you take a look at the next video which explains how you can easily substitute the G wire for the C wire, please be aware this works best if you have a gas, propane or forced air conventional heating and cooling system.

Using this method will also remove the ability to control you fan, however it will still run when your system does.

Adding a Transformer

Yet another way to solve the whole C wire issue is to install an external transformer. This may have some of you running for the hills! However, by watching the following 5 minute video, you will learn how simple it is to wire an external device into your system which will allow you to use a thermostat that needs a C Wire.

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