The ultimate guide to smart thermostats

What is a smart thermostat?

Have you ever touched down on holiday only to remember that you hadn’t turned the heating off? Never fear - there’s an app for that. Smart thermostats allow you to take control of your home’s heating systems at a distance. They also offer a bevy of cost-saving features to cut your energy bills. 

Smart thermostats offer a simple way to control your home’s temperature remotely, either via a smartphone, tablet or desktop computer. They put your heating system online, allowing you to change the temperature or turn the heating off and on using an app. Be sure not to confuse the smart thermostat with a smart meter, which sends digital meter readings to your energy supplier. 

So how does it differ from a standard thermostat? Although they offer the same functions – programming a heating schedule or adjusting room temperature – smart heating offers various additional high-tech features, some of which learn your habits over time to provide you with a personalised service. Smart Wi-Fi thermostats work with most standard boilers, as well as communal heating systems. If you’re unsure, check the manufacturer’s website to find out which boilers are compatible. 

There are three basic components to any smart thermostat. The first plugs into your boiler, allowing the thermostat to communicate with the heating system. The second is the in-home device and control panel, while the third is the smartphone app. 

Reasons to install a smart thermostat

There are many benefits to smart thermostats. If you have any unexpected change of plans and know you won’t be home until later than usual, you can adjust the heating to warm up the home in time for your new arrival. You can heat the home during cold snaps to avoid burst or frozen pipes, even when you’re away on holiday. In the case of designs that learn your habits over time, you can receive tailored heating programming that’s specific to your individual movements within the home. 

Although smart heating won’t save you money directly, these systems do offer savings in the long run by making the home more efficient. Like smart meters, smart thermostats put you in control of your usage, so you can adjust your own behaviour to save money. However, for those who have very defined habits, a standard programmable thermostat may be enough. 

Common features of smart thermostats

To find the best smart thermostat, it’s helpful to compare the different features. Not all models are created alike. Here’s a rundown of the different capabilities you might expect from models currently on the market.

Remote temperature control

The main feature common to the best smart thermostats is the ability to control your heating using your smart device of choice. You can do this whether you’re lounging about at home or enjoying a holiday abroad. 

Multi-zone control

Some models allow you to heat different areas of the home independently of one another. This is helpful if you have a spare room that only gets used when guests are in town, or you need to keep the baby’s room a bit warmer than the rest of the house. When you’re unable to physically adjust the radiator valves for whatever reason, multi-zone control comes in quite handy. These do require the additional cost of smart thermostatic radiator valves. 


Another feature to keep an eye out for is geofencing. This is a technology that virtually tracks when a user enters or leaves the property. It’s a simple way of creating a boundary around your home, so that the system can switch the heating on when you arrive and shut it down when you’ve departed.

Hot water control

Some smart thermostats will control the hot water along with the heating. These usually only work for properties with a separate hot water tank, and some will require an extra device to work. 

Preventing frozen pipes

Frozen pipes in the winter can be a major headache, but you can prevent this by putting your thermostat into a special holiday or safety mode. With this type of setting, the thermostat automatically switches the heating back on if it detects the temperature dropping below a safe number. Some also detect draughts from open windows and can send you an alert. 

Regular usage feedback

Are you looking for ways to get a handle on your energy use? Look for a model that offers regular feedback about your habits. This shows you just how many hours of the month have been spent heating the home. You can compare this to your usage history so you can see what’s changed. Models like the Nest smart thermostat offer energy-efficient settings to help you adjust your habits. 

Communication with other smart devices

If you’re already connected to smart home products like Google Home or Amazon Echo, you can add your new smart thermostat into the mix. Once they’re connected, you can speak to Alexa or Google to control heating with voice commands. 

Types of smart thermostat

There are loads of smart thermostats on the market today, ranging from big names like Google and British Gas to smaller upstarts. Here’s a rundown of some of the top types of thermostats to choose from. 

British Gas Hive

Hive Active Heating allows you to manage your home’s temperature remotely, whether you’re at home or away. You can download the corresponding app or use a central dashboard to manage your heating options. This puts the user in control, which is appealing for those who aren’t quite ready to hand over all their data just yet. You can design your own heating schedules and adjust temperatures whenever you wish. The heating automatically shuts off using Hive if the pipes are in danger of freezing. It also gives you historic information of temperatures both in and out of the home.

Google Nest

Acquired by Google in 2014 for £2 billion, the Nest smart thermostat monitors your habits, particularly during the week, and adjusts your heating accordingly. The home’s temperature adapts to your behaviour with this Learning Thermostat, with the end goal being that you’ll never have to fiddle with the heating at all – it does the job for you. Nest also offers a motion sensor, turning heating off automatically when the home is vacant. 

Honeywell Evohome

Evohome is a Honeywell smart thermostat that works by splitting your home into different smart zones. You’ll be able to control the heating in each zone, so that you don’t waste energy in rooms you’re not using. Honeywell claims that this device helps the average home save up to 40% on annual heating costs by eliminating wasted energy.

As you can see, the cost of smart thermostats will vary depending on the type and brand. All the big six suppliers offer their own preferred design, and in some cases, it’s included as part of your energy tariff. It’s well worth comparing the options to find out if you could save on your energy bills by choosing a plan with a free smart thermostat installation included. 

Ben GallizziEnergy Expert - Nov 1st 2019