I Want a Smart Thermostat but Don't Have a C Wire - What Are My Options?

June 09, 2021

When you’re seeking ways to decrease heating and cooling expenses, upgrading to a smart thermostat is a wise idea. These devices pick up on the temperatures you like and routine and then make an energy-efficient schedule to match. What’s even better is that you can regulate and keep an eye on your settings from almost anywhere with your phone, whether you’re lying in bed or on the go. (You might even be eligible for a free smart thermostat depending on rebate programs from your utility company in Grand Prairie.)

In most instances, installing a smart home thermostat with the help of Bon Air Service Company is an uncomplicated job if you have a more modern house. 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 navigate the process so you can select the right thermostat and receive energy savings for many years.

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

Many programmable thermostats run on batteries. When you’re switching to a smart thermostat, you’ll find that many have to have a C wire, or common wire, for power. If you don’t have this wire, your new thermostat could cause your heating and cooling system to have malfunctions.

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

  1. Switch off power to the thermostat at the breaker.
  2. Take off the thermostat and check the wiring.
  3. If there are five or six multicolored wires, you have what’s required for a smart thermostat. You might be thinking what color is the C wire on a thermostat—and the answer to that is typically blue.
  4. If there are three or four thin multicolored wires, you’re almost there. Make sure the C wire isn’t tucked in the wall. If you can’t find one, we may be able to install one for you or you may be able to use your new thermostat without one.
  5. If you have two thick wires, you may be able to install a smart thermostat with an adaptor just 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 won’t work and you don’t want to replace it.

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 could be an option for you.

Nest says its thermostats are made to run on minimal power and can frequently share it with your heating and cooling system. However, you may need to have a pro like Bon Air Service Company put in a C wire with the Nest Thermostat E or Nest Learning Thermostat if you’re running into power problems or a battery that’s frequently drained.

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

Trust Bon Air Service Company for Your Smart Thermostat Installation Needs

At Bon Air Service Company, we’re always looking for ways to keep you cozier while keeping energy costs inexpensive. If you want to learn more about switching to a smart thermostat without a C wire, reach us at 972-332-1028. We can help you select the right model for your residence and even add new wiring if necessary.