I Want a Smart Thermostat but Don't Have a C Wire - What Do I Do?

June 09, 2021

When you’re wanting approaches to decrease utility expenses, installing a smart thermostat is a wise decision. These devices learn your temperature preferences and routine and then create an energy-efficient schedule that matches. What’s even better is that you can regulate and keep an eye on your settings from nearly anywhere with your phone, whether you’re sitting in bed or away from home. (You might even be able to receive a free smart thermostat depending on rebate programs from your utility supplier in Central Point.)

Most of the time, adding a smart home thermostat with the help of Titan Heating & Air Conditioning is a straightforward task if you have a new home. But what if your home is older or doesn’t have the proper wiring? Can you still install a smart thermostat without C wire? We’ll help you figure out the process so you can choose the recommended thermostat and get energy savings for a long time.

What Is a C Wire and What Does It Do on a Thermostat?

The majority of programmable thermostats run on batteries. When you’re making the move to a smart thermostat, you’ll find that many require a C wire, or common wire, for power. If you don’t use this wire, your new thermostat might cause your heating and cooling system to have malfunctions.

You can determine if you have a C wire by doing the following:

  1. Turn off power to the thermostat at the breaker.
  2. Pull off the thermostat and look at the wiring.
  3. If there are five or six multicolored wires, you have what you need for a smart thermostat. You might be wondering what color is the C wire on a thermostat—and the answer to that is usually blue.
  4. If there are three or four thin multicolored wires, you’re nearly there. Make sure the C wire isn’t hidden in the wall. If you can’t find one, we may be able to install one for you or you may be able to run your new thermostat without one.
  5. If you have two thick wires, you may be able to use a smart thermostat with an adaptor specifically for high-voltage systems. Or you may be able to operate a battery-powered smart thermostat, like the Lux Geo Wi-Fi Thermostat, if your wiring is incompatible and you don’t want to put in new wiring.

Do Nest or ecobee Need a C Wire?

Two of the best-selling brands are the Nest smart thermostat and ecobee smart thermostat. If you have two to four wires, these thermostats might work for your home.

Nest says its thermostats are made to require minimal power and can often share it with your home comfort system. However, you may need to have a professional like Titan Heating & Air Conditioning add a C wire with the Nest Thermostat E or Nest Learning Thermostat if you’re having power problems or a battery that’s always drained.

ecobee works with 24-volt systems (ones with three to six thermostat wires) and has a C wire adaptor. So, you’re taken care of if you don’t have a thermostat C wire.

Trust Titan Heating & Air Conditioning for Your Smart Thermostat Installation Needs

At Titan Heating & Air Conditioning, we’re always seeking approaches to keep you more comfortable while keeping heating and cooling bills reasonable. If you want to learn more about switching to a smart thermostat without a C wire, reach us at 514-600-5499. We can help you choose the right model for your residence and even install new wiring if necessary.