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

June 09, 2021

When you’re looking for ways to lower heating and cooling costs, upgrading to a smart thermostat is a wise idea. These devices adjust to your favorite temperatures and routine and then make an energy-efficient schedule that fits. What’s even better is that you can regulate and watch your settings from nearly anywhere with your phone, whether you’re sitting in bed or out and about. (You might even be able to get a free smart thermostat depending on rebate programs from your utility provider in Temple/Belton.)

Most of the time, hooking up a smart home thermostat with the help of Bell Air Conditioning Inc is a simple job if you have a more modern home. 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 figure out the process so you can select the recommended thermostat and get energy savings for many years.

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

Many programmable thermostats use batteries. When you’re switching to a smart thermostat, you’ll learn that many require a C wire, or common wire, for power. If you don’t use this wire, your new thermostat may cause your heating and cooling system to malfunction.

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

  1. Switch 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 pondering 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. 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 run your new thermostat without one.
  5. If you have two thick wires, you may be able to install 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 isn’t right 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 match for your home.

Nest says its thermostats are designed to run on minimal power and can typically share it with your heating and cooling system. However, you may need to have a specialist like Bell Air Conditioning Inc add 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 connects 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 Bell Air Conditioning Inc for Your Smart Thermostat Installation Needs

At Bell Air Conditioning Inc, we’re always looking for methods to keep you cozier while keeping utility costs reasonable. If you have questions about upgrading to a smart thermostat without a C wire, give us a call at 254-307-9572. We can help you select the right model for your home and even install new wiring if required.