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 reduce energy costs, upgrading to a smart thermostat is a wise decision. These devices pick up on the temperatures you like and routine and then develop an energy-efficient schedule that matches. What’s even better is that you can regulate and keep an eye on your settings from almost anywhere with your phone, whether you’re relaxing in bed or away from home. (You might even be eligible for a free smart thermostat depending on rebate programs from your utility supplier in Sacramento.)

Most of the time, adding a smart home thermostat with the assistance of American HVAC Inc is an uncomplicated task if you have a more modern house. But what if your home is older or doesn’t have the proper wiring? Can you still add a smart thermostat without C wire? We’ll help you navigate the process so you can choose the ideal thermostat and enjoy energy savings for many years.

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

The majority of programmable thermostats run on batteries. When you’re switching to a smart thermostat, you’ll discover that many require 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 ascertain if you have a C wire by doing the following:

  1. Turn off 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 required for a smart thermostat. You might be wondering 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 nearly there. Check the C wire isn’t rolled up 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 use 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 install a battery-powered smart thermostat, like the Lux Geo Wi-Fi Thermostat, if your wiring is incompatible and you don’t want to install new wiring.

Do Nest or ecobee Need a C Wire?

Two of the most popular brands are the Nest smart thermostat and ecobee smart thermostat. If you have two to four wires, these thermostats might be a fit for your needs.

Nest says its thermostats are made to need minimal power and can typically share it with your HVAC system. However, you may need to have a specialist like American HVAC Inc put in a C wire with the Nest Thermostat E or Nest Learning Thermostat if you’re having power problems or a battery that’s always drained.

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

Depend on American HVAC Inc for Your Smart Thermostat Installation Needs

At American HVAC Inc, we’re always on the lookout for approaches to keep you more comfortable while keeping utility expenses low. If you want to learn more about switching to a smart thermostat without a C wire, reach us at 916-243-6714. We can help you choose the right model for your residence and even put in new wiring if required.