When you’re looking for approaches to lower heating and cooling costs, getting a smart thermostat is a wise decision. These devices adjust to your favorite temperatures and routine and then create an energy-efficient schedule to match. What’s even better is that you can change and keep an eye on your settings from nearly anywhere with your phone, whether you’re sitting in bed or on the go. (You might even be able to receive a free smart thermostat depending on rebate programs from your utility company in The Bay Area.)

In many instances, adding a smart home thermostat with the help of Contra Costa Heating & AC is a simple job if you have a more modern house. But what if your house is older or doesn’t have the correct wiring? Can you still add a smart thermostat without C wire? We’ll help you figure out the process so you can pick the recommended thermostat and receive energy savings for a long time.

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

Many programmable thermostats use batteries. When you’re making the move 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 may cause your heating and cooling system to have glitches.

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

  1. Cut 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’s needed for a smart thermostat. You might be wondering 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 hidden inside the wall. If you can’t find one, we may be able to install 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 install 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 your needs.

Nest says its thermostats are designed to run on very little power and can frequently share it with your heating and cooling system. However, you may need to have a specialist like Contra Costa Heating & AC add 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 connects 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 Contra Costa Heating & AC for Your Smart Thermostat Installation Needs

At Contra Costa Heating & AC, we’re always seeking methods to keep you more comfortable while keeping energy costs reasonable. If you want to know more about installing a smart thermostat without a C wire, reach us at 510-343-9841. We can help you pick the right model for your home and even install new wiring if needed.