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Smart Thermostat Compatibility: Radiators, Boilers, Heat Pumps

Smart thermostats save energy, reduce costs, and are incredibly easy to install and use. With efficient, intuitive, and optimal temperature regulation throughout the year, you no longer have to go through the tedious process of manually adjusting your HVAC system every when the seasons change. 

Smart thermostats are designed to be compatible with most low voltage (24 V) HVAC system types, including radiators, boilers, and heat pumps. Some systems may require a C wire or other advanced configurations. It’s quick and easy to scope your system requirements before you purchase a thermostat.

Let’s dig a little deeper into smart thermostat compatibility with heating and cooling systems. First, we can take a quick look into how smart thermostats work. Then, we’ll cover the adjustments required to make an HVAC system compatible. We will also look at how smart thermostats work with different types of HVAC systems and, finally, how to select the best smart thermostat for your home. 

How Does a Smart Thermostat Work?

Smart Thermostat with a person warming up the room temperature with a soft shadow

A thermostat regulates the temperature of an enclosed area. It’s connected to a larger system of switches, valves, relays, burners, heaters, cooling units, outlets, and more. With the use of the thermostat, one can easily increase or decrease the temperature generated by the system.

A smart thermostat makes this process more efficient and sophisticated. 

Unlike a regular thermostat, your smart thermostat does not require commands from you to regulate the temperature of your home. Instead, it’s connected to the internet and has access to regular weather updates. It’s also connected to your smartphone, allowing for remote access. 

Moreover, smart thermostats are designed to be intuitive and to adapt to the recurring heating and cooling patterns of your household so that it can adjust the heating process accordingly. This may involve keeping the heating off to save energy when you’re away and getting the home comfortably heated once again before you return. 

How to Check the General Compatibility of Your Smart Thermostat

There are a few simple checks and adjustments you may need to do to make sure that your smart thermostat functions seamlessly with your existing system. A smart thermostat needs a continuous power supply in order to function well, so a C wire is often a requirement.

Your home should should have a functioning HVAC system that your smart thermostat can work with. 

Here are a few checks you can do to determine how compatible the heating system in your home is for a smart thermostat:

  • Turn off the main switch of your home or the breaker for your HVAC system. Safety first!
  • Remove the faceplate of the existing thermostat in your home to check the wiring. (Remember to take pictures of your existing wiring to make sure you can put it back properly.)
  • Check the “C terminal” of your thermostat to see if a cable is attached there. 
  • If there is no cable connected, remove the thermostat and gently pull it away from the wall to see if there is a C wire that is unused coiled behind. 

Note: A C wire, or a common wire, helps deliver power from the HVAC system to the smart thermostat if the other wires are not capable of providing enough power. 

If there is no C wire, a professional installer should be able to rewire it to be compatible with your new smart thermostat. The need for a C wire varies depending on the heating system you have and also the kind of smart thermostat you’re using.

You can check if your new smart thermostat can work without a C wire in the manual or on the manufacturer’s website. 

Smart Thermostat Compatibility With Radiators

Radiators in your HVAC system use the basic convection principle to heat your home through its valves. When a radiator is filled with hot water, it effectively heats up the surrounding air, which then circulates around an enclosed space distributing heat. 

Many smart thermostats including the Google Nest Thermostat (on Amazon) work well with your existing radiator valves. Before you buy the device, make sure you check its specifications to see the compatibility with radiator valves.

When you install the smart thermostat, you can adjust your radiator values to a setting that you prefer. Then, you can use the smart thermostat to regulate them as you wish so you will not have to adjust the valves often. 

Smart Thermostat Compatibility With Boilers 

The boiler is a core part of your HVAC system. It is basically a container of liquid, often water, that uses a source of energy to heat the liquid and distribute the heat throughout the house using radiator valves.

There are several types of boilers depending on their function and the source of energy they use to produce heat. For example, there are OpenTherm boilers, Condensing boilers, Biomass boilers, and Combi boilers.

Smart thermostats are designed to work well with many different kinds of boiler systems. Depending on the smart thermostat you have, you are able to control the temperature of the water used to heat your home.

Modern boiler systems allow smart thermostats to communicate when and how to increase or decrease the temperature of the boiling liquid.

For example, an OpenTherm boiler may use less gas to reach a lower temperature of the water as instructed by a smart thermostat. This precise control in the boiler means that the energy is used more efficiently than with a regular thermostat.  

Smart Thermostat Compatibility With Heat Pumps

A heat pump provides both heating and cooling to an enclosed space. A heat pump functions similarly to an air conditioner, using cold or heated air from outside to provide the required temperature to the inside of a home.

They are often more energy-efficient since they transfer heat as opposed to using a source of energy to create it. 

A majority of smart thermostats work well with heat pumps, and together they make highly efficient and eco-friendly heating and cooling systems. You can connect your smart thermostat to the heat pump system in your home to control the temperature remotely and easily.

With room sensors, you can even set up specific heating instructions for different rooms. 

The installation process of a smart thermostat to a heat pump system can be trickier than that of a regular HVAC system. Most of them require a C wire, and most smart thermostats come with a power extender kit for the houses that do not have C wires connected to their existing thermostats. 

How Do I Pick the Right Smart Thermostat for My Home?

Smart Thermostat with a person saving energy with a smart device on a white background

The first step to selecting the right smart thermostat for your home is to study the existing heating and cooling system in your home. This will help you buy the most compatible smart thermostat.

Some important questions include: What kind of a furnace or boiler do I have? Does it have a heat pump? Does it have a hybrid heating system? What is the source of energy it uses? What kind of air ducts or radiators does it have?

Then, go through your smart thermostat options to find one that is compatible with the system that you have. Almost all the popular smart thermostat brands including Google Nest, Honeywell, and ecobee (on Amazon) have compatibility checkers that you can go through. 

For optimal functioning of your smart thermostat, you need to have a strong WiFi connection and a smart device such as a smartphone or a tablet for remote control capabilities. Most smart thermostats are simple enough that you can install them yourself.

If they need more advanced configuration and wiring, get the help of a professional. 

Once you have installed the device and set it up on your smart device, don’t be afraid to try out and use all the cool features they offer, and to customize its function for you and your home!