woman adjusting her smart thermostat

Can You Replace Your Thermostat with Any Thermostat?

The home of the future is here today with so many smart technologies and a variety of new tools that make our lives easier and more convenient. One of these new technologies is the smart thermostat. You might be itching to have one of these installed in your home, but it is important to check that your HVAC system is compatible with the smart thermostat you purchase.

Heartland Heating, Air, and Plumbing share some tips on how you can tell if your thermostat is compatible with your HVAC system and how to choose which thermostat is best for your Murphysboro, IL home.

3 Types of Thermostat Systems

In order to figure out if you can replace your thermostat with any thermostat, first, you need to find the wires that connect your heating and cooling system to your thermostat to find out which kind of thermostat you currently use.

To do this, you will need to take the faceplate of your thermostat off and remove your thermostat from the wall. You’ll want to turn the air conditioner or furnace off at the breaker first to be safe. In order to do this, you’ll be looking at the electrical wires that connect to your thermostat. If you are uncomfortable with doing this, call Heartland to have an experienced technician take care of this for you.


Low voltage thermostats are the most common. They typically run on 24 volts of electricity, although some use as low as 6 volts and as high as 30 volts. Usually, you’ll see two or three thermostat wires, but there may be more wires if you have a heat pump. These wires are similar to those you would find in a doorbell or a phone jack, fairly thin wires designated with different colors.


Line-voltage thermostats are directly powered by a standard 120-volt or 240-volt circuit. These thermostats are primarily used for electric resistance heating systems like electric baseboards or in-wall heaters. The wires attached to the thermostat to the wall will be 2-4 thick 12 gauge or 14 gauge wires like those connected to a wall outlet or a light switch.


Millivolt systems are not very common and are usually only used for direct or top vent wall furnaces. These systems require even less voltage than a low voltage system, operating only at 750 millivolts, or .75 volts.

How Do I Choose a Smart Thermostat?

You most likely have a low voltage thermostat in your home since they are the most common. Most smart thermostat systems are low voltage systems themselves. It’s a good idea to read reviews, ask people you know with smart thermostat systems, and compare prices and efficiency ratings of thermostats before making a choice. It’s also smart to check the company’s return policies in case you purchase a thermostat that does not work to control your HVAC system.

The Google Nest, Ecobee, and Honeywell smart thermostats are some of the most popular brands on the market today. Each of these companies offers an interactive tool that walks you through the steps of determining what kind of thermostat you currently use to recommend the best model that is compatible with your home’s heating and cooling system.

Heartland Can Help With Thermostat Compatibility and Installation

Besides wanting the latest technology in your home, why else do you want a new thermostat? Thermostats can often cause home comfort issues. Sometimes, your thermostat may be too close to an appliance that gives off heat, or on an exterior wall where it can feel a draft, or gets lots of direct sunlight. All of these factors can skew the thermostat’s temperature reading of your home and make your home uncomfortable. This can be remedied by moving your thermostat and installing a new one as well.

Thermostats can also break and can be fixed by one of our technicians. It’s also smart to swap out your thermostat every time you get a new HVAC appliance installed. For all your home comfort issue needs, you can count on Heartland for expert installation, repair, and maintenance.

Schedule Thermostat Installation with Heartland Today

If you’re ready to upgrade your home’s heating and cooling systems, talk to Heartland for expert service. Our team of experienced technicians can install your new thermostat for you to make sure it will properly control your HVAC system. Schedule an appointment with Heartland today.