How to use smart thermostats

You can take charge of your household energy use and control heating remotely using the latest generation of smart thermostats. What is a smart thermostat, and is it worth installing one?

Smart thermostat on wall

In this guide:

  • Smart heating: what is a smart thermostat?

  • How do I control my home heating remotely?

  • How does smart heating work?

  • What are typical smart heating controls?

  • How much does smart heating cost?

  • Can I save money when I control my heating remotely? 

  • Why would I control my heating from my phone?

  • Which central heating thermostat is best?

Smart heating: what is a smart thermostat?

Smart thermostats are often confused with smart meters, but they’re different in many ways. For starters, you can install a smart thermostat yourself without the need for an engineer to call, and they have no impact on switching suppliers.

Smart thermostats are a tool to link your central heating system to the internet via your local network – unlike smart meters which use their own dedicated cellular network to send and receive data. This places the controls of your central heating at your fingertips whether you happen to be in a different room to your boiler or away from home.

Smart thermostats can be controlled by an accompanying device or app and come with a range of built-in features to help you monitor and control household energy use. All that’s needed is an internet connection.

How do I control my home heating remotely?

Although features vary, all smart thermostats include a programmer or scheduler designed to let you set up a timed heating plan. Instead of fiddling with a regular device, you can do this on your phone or computer. 

So, how do smart thermostats differ from a traditional thermostat? Although they perform the same basic function, smart thermostats come with added features. They learn your household habits and what temperatures you prefer, helping to intuitively heat your home in a way that prevents energy being unnecessarily wasted.

Will a smart thermostat work with my boiler?

In most cases, yes. Smart thermostats work with most standard gas and electric boilers. Generally, if you can control your boiler with a standard programmer or thermostat, a smart version will be compatible. However, they usually won’t work with heat pumps or storage heaters. 

How does smart heating work?

Smart thermostats comprise three main components: the first plugs into your boiler to communicate wirelessly with the second part, an in-home device similar to your smart meter’s home monitor. This device replicates the function of your old thermostat’s dial or digital control panel, but utilises a more user-friendly interface to simplify the process of setting up your heating system.

The third component is an optional app for your smartphone, laptop or tablet, which lets you place your home heating controls in your pocket for access from anywhere in the house or even when you’re away from home.

In addition to replicating the controls of your existing thermostat, smart thermostats employ machine learning to learn your heating habits to provide you with advice on smart energy usage. They can also warn you when they detect windows are open or use GPS to switch on the heating automatically when you’re travelling home.

What are typical smart heating controls?

While all smart thermostats provide the convenience of allowing you to control your heating from your device, there are additional smart heating controls that take things to the next level: 

  • Zoned heating

Most of today’s smart thermostats let you heat different parts of your home separately, with a multi-room or multi-zone design. For zoned heating, you’ll need to purchase additional smart thermostatic radiator valves to place in each room. Whether or not you need zoned heating will depend on the size of your home. For larger homes with multiple rooms, this offers a way to save energy because you can heat only those rooms in use at any given time. 

  • Geofencing

Another typical feature of smart thermostats is geofencing. This creates a virtual boundary to control your heating. It tracks when your mobile device enters or leaves the location in question. With smart thermostats, this is used to track when you’re leaving or returning home, so that heating can switch on and off automatically. 

  • Hot water controls

Many thermostats also offer smart heating controls to control your hot water – but you’ll almost certainly need a separate hot water tank.

  • Smart learning

Models like the Nest Learning Thermostat track your heating habits and make automatic adjustments over time based on your behaviour – for example, taking note of when you turn the temperature up and down to calculate which temperatures you prefer and when. The thermostat will then programme itself with this data – but you can always override it. 

  • Heating feedback

A useful feature for anyone interested in saving energy is the feedback offered. Like smart meters, these thermostats give you a report showing you how many hours you spend heating your home. They can even show you how to save energy, with data about which thermostat settings are most efficient. 

  • Holiday mode

You can set your thermostat before you go on holiday, so that the system switches on automatically to stop pipes freezing or detect open windows when you’re not there. 

How much does smart heating cost?

The cost will vary widely depending on the model you choose. Generally, they cost between £150 and £280, with installation costing anything between £50 and £100 if you need an engineer to install it for you. However, some models are simple enough to install yourself. 

Some energy suppliers will offer a smart thermostat for free as part of your tariff, so it’s worth comparing deals to see if you can get one included with your energy package. There are also monthly payment plans for some smart thermostats, like British Gas’s plan for Hive Heating where you only pay a few pounds per month.  

Can I save money when I control my heating remotely? 

Installing smart heating alone won’t automatically save you money. However, they’re designed to encourage you to learn about – and change – your habits. Monthly reports let you see when and where you’ve been using the most heating. Features like zoned heating can also save money in larger households, since you can restrict heating to where as well as when you need it most. 

These little changes add up over time. For example, the Energy Saving Trust states you can save £80 per year by turning your thermostat down by just one degree.

Why would I control my heating from my phone?

If your schedule varies from day to day and you come home at different times, smart heating controls on your mobile give you the option of delaying heating when outside your home. Those who are away frequently for work, holiday or social reasons will benefit most from this type of system. 

However, those with set routines may not find this so useful, since you can use a traditional thermostat to create a daily heating schedule. Similarly, if you work from home you can just get up and adjust the heating manually.

What should I look for in a smart thermostat?

To find the best smart thermostat for your needs, there are a few factors to consider. In addition to cost, you should look for the following features:

FeatureWhy choose it?
Multizone Control heating in different parts of your home on a per-room basis
Hot water control Take control of your hot water with an app
Temperature alerts Receive automatic alerts when your internal temperature gets too high or low
Open window alerts Receive an alert if a window is opened so you can switch off the heating to prevent energy wastage
Frost protection Protect your home from freezing pipes by automatically turning on the heating when the temperature drops to a certain level
Weather forecasts Sync your heating controls to the current forecast
Automatic learning system Smart thermostat learns your household habits over time to predict preferred temperatures

Which central heating thermostat is best?

That answer depends on your current central heating system, energy plan and supplier. That’s because some systems are owned or linked to specific energy suppliers. Here’s some of the big-names smart thermostat systems to look at:

British Gas Hive

Owned by British Gas, the Hive thermostat offers features like temperature notifications, weather forecasts, frost protection and geolocation. It also gives you historical information about temperatures both in and out of the home, allowing you to predict and learn from heating habits. British Gas customers can access special discounts on Hive products, including installation. 

Google Nest

The Google Nest is a smart thermostat that learns your habits and adjusts temperatures automatically according to your preferences. It includes all the features you’d expect, including holiday mode, multizone heating and geolocation. One feature that stands out is the green leaf symbol. This pops up if your thermostat is adjusted to an energy-efficient temperature, so you know just when you’re saving energy. Google Nests are supplied as part of selected tariffs from suppliers like Shell Energy and SSE.

tado° 

tado° provides the same features and access to information as its competitors with multizone heating, hot water control, open window detection and more. It also helps you save money on your bills by giving you estimated savings figures, so you can see the difference if you were heating your home with a traditional thermostat. Like Google Nest, it adapts to your lifestyle for smart heating in the home with very little input from you. You can purchase the device outright from tado° or E.ON, or choose a rental contract with an option to buy at the end of the fixed period if you wish.

These are only a few examples of what’s out there. You’ll also find options from companies like Honeywell, Heatmiser, EDF Energy and more. Be sure to compare features, costs, and reviews to find the best fit for your home.

Last updated: 27 November 2020