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

June 09, 2021

When you’re wanting approaches to lower utility costs, upgrading to a smart thermostat is a wise decision. These devices adjust to your temperature preferences and routine and then create an energy-efficient schedule to match. What’s even better is that you can regulate and monitor 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 provider in McMurray.)

In many instances, hooking up a smart home thermostat with the assistance of Kowalski Heating, Cooling & Plumbing is a simple job if you have a new residence. But what if your home is older or doesn’t have the correct wiring? Can you still add a smart thermostat without C wire? We’ll help you navigate the process so you can pick the recommended thermostat and get energy savings for many years.

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

Most programmable thermostats run on 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 use this wire, your new thermostat might cause your heating and cooling system to have glitches.

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

  1. Turn off power to the thermostat at the breaker.
  2. Remove 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 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 nearly there. Check the C wire isn’t rolled up 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 run a smart thermostat with an adaptor designed 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 install 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 work for your needs.

Nest says its thermostats are created to require minimal power and can often share it with your heating and cooling system. However, you may need to have a specialist like Kowalski Heating, Cooling & Plumbing 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 always drained.

ecobee works 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.

Depend on Kowalski Heating, Cooling & Plumbing for Your Smart Thermostat Installation Needs

At Kowalski Heating, Cooling & Plumbing, we’re always on the lookout for methods to keep you comfier while keeping energy bills low. If you have questions about switching to a smart thermostat without a C wire, reach us at 724-370-0141. We can help you pick the right model for your house and even add new wiring if necessary.