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

June 09, 2021

When you’re seeking methods to lower utility costs, upgrading to a smart thermostat is a smart decision. These devices pick up on the temperatures you like and routine and then make an energy-efficient schedule that fits. What’s even better is that you can regulate and monitor your settings from just about anywhere with your phone, whether you’re lying in bed or out and about. (You might even be able to get a free smart thermostat depending on rebate programs from your utility company in Heflin.)

In most instances, hooking up a smart home thermostat with the support of Bain Heating & Air Conditioning, Inc is a straightforward job if you have a new house. But what if your house is older or doesn’t have the proper wiring? Can you still have a smart thermostat without C wire? We’ll help you demystify the process so you can select the correct thermostat and get energy savings for many years.

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

The majority of programmable thermostats use 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 may cause your heating and cooling system to have malfunctions.

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

  1. Cut 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 needed for a smart thermostat. You might be thinking what color is the C wire on a thermostat—and the answer to that is often blue.
  4. If there are three or four thin multicolored wires, you’re almost there. Ensure the C wire isn’t tucked inside the wall. If you can’t find one, we may be able to put in one for you or you may be able to operate your new thermostat without one.
  5. If you have two thick wires, you may be able to install 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 won’t work and you don’t want to replace it.

Do Nest or ecobee Need a C Wire?

Two of the top brands are the Nest smart thermostat and ecobee smart thermostat. If you have two to four wires, these thermostats may be a match for your home.

Nest says its thermostats are created to run on not a lot of power and can frequently share it with your home comfort system. However, you may need to have a specialist like Bain Heating & Air Conditioning, Inc install a C wire with the Nest Thermostat E or Nest Learning Thermostat if you’re experiencing power problems or a battery that’s frequently drained.

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

Trust Bain Heating & Air Conditioning, Inc for Your Smart Thermostat Installation Needs

At Bain Heating & Air Conditioning, Inc, we’re always looking for ways to keep you cozier while keeping energy expenses low. If you want to know more about installing a smart thermostat without a C wire, contact us at 256-270-1196. We can help you pick the right model for your residence and even add new wiring if required.