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

June 09, 2021

When you’re looking for approaches to reduce heating and cooling bills, upgrading to a smart thermostat is a smart decision. These devices adjust to your favorite temperatures and routine and then create an energy-efficient schedule that matches. What’s even better is that you can regulate and watch your settings from nearly 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 supplier in Booneville.)

In many instances, adding a smart home thermostat with the support of Booneville Heating & Cooling LLC is a simple job if you have a newer home. But what if your residence is older or doesn’t have the right wiring? Can you still add a smart thermostat without C wire? We’ll help you figure out the process so you can choose the ideal 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 need batteries. When you’re switching to a smart thermostat, you’ll discover 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 glitches.

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 look at the wiring.
  3. If there are five or six multicolored wires, you have what’s required for a smart thermostat. You might be pondering 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 close. Ensure the C wire isn’t hidden within 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 use a smart thermostat with an adaptor specifically for high-voltage systems. Or you may be able to use a battery-powered smart thermostat, like the Lux Geo Wi-Fi Thermostat, if your wiring won’t work and you don’t want to put in new wiring.

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 fit for your needs.

Nest says its thermostats are made to run on not a lot of power and can typically share it with your heating and cooling system. However, you may need to have a professional like Booneville Heating & Cooling LLC install 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 has a C wire adaptor. So, you’re good if you don’t have a thermostat C wire.

Depend on Booneville Heating & Cooling LLC for Your Smart Thermostat Installation Needs

At Booneville Heating & Cooling LLC, we’re always seeking methods to keep you cozier while keeping energy costs inexpensive. If you want to know more about upgrading to a smart thermostat without a C wire, reach us at 662-269-8716. We can help you choose the right model for your residence and even add new wiring if needed.