7 ways you've been using your thermostat wrong (and it's been costing you money) — this is what heating experts say to do instead
Now is not the time to be wasting energy
When the temperature drops at this time of year, we all use our heating more in order to stay warm. An unhappy side effect of that is that our energy bills are the highest at this time of year too. But it turns out that you could be wasting money unnecessarily if you are using your thermostat wrong.
Knowing how to save energy at home is vital if you want to keep your gas and electricity bill as low as possible. But our heating systems can often feel like minefields, with people reluctant to mess with it for fear of causing it to fail at a time of year it's needed most.
However, according to heating experts, there are a whole host of simple errors that households make when it comes to room thermostats that are wasting energy and sending heating bills soaring. Fortunately, they are easily rectified.
How many do you think you're guilty of making?
1. Whacking your thermostat up to heat your home faster
When it comes to how a thermostat works, it's a common misconception that turning your thermostat up to a higher temperature will heat your home quicker, and it's one that heating experts advise against.
'Many people believe that turning the thermostat up higher will heat their home faster, but it doesn’t,’ explains Adam Knight, Lead Engineer at BOXT. ‘Your heating system works at the same speed no matter what temperature you select. Instead, set your desired temperature and let the thermostat do the work. It will only call for heat when needed, keeping your home comfortable without wasting energy.’
Instead, it's best to programme your heating to come on about 30 minutes before you are due to return home, so you aren't coming back to what feels like a fridge.
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If that's not feasible, then it could be worth having one of the best oil-filled radiators or electric heaters on hand to temporarily take the edge off in the room you are in while you wait for the central heating to warm up. These plug-in options will heat up quickly and are most cost-efficient when used in short bursts.
2. Never adjusting the temperature
If you never adjust the temperature on your thermostat, you're definitely wasting energy unnecessarily. Get into the habit of adjusting your thermostat before you go to bed to reduce your energy bills.
'Many homes stay at daytime temperatures even when everyone is asleep, which wastes energy because most people are comfortable at a lower setting overnight,' says Adam. 'Turning the thermostat down by a couple of degrees at night reduces costs without affecting comfort, saving money while you sleep.'
This will also ensure that you pay more attention to the temperature your thermostat is set at, and determine whether you could actually be as comfortable in your home if you knock it down a degree or two, which can save around £100 per year on your energy bills.
3. Not scheduling your heating
Another mistake you may have been making with your thermostat is having it set on a low temperature, but leaving your heating on constantly, instead of programming it to come on only when you need it.
'Scheduling your heating, so it is off when you are not at home can be a big energy cost saver,' explains Stephen Hankinson, heating expert at Electric Radiators Direct. 'If you like being comfortable as you get ready in the morning, you can program your heating to switch on just before you wake up and then off again by the time you leave. Remember the program may need adjusting when the clocks change.
'Similarly, if you’re going away for an evening or a few days, make sure to change your heating schedule to reflect this and ensure you’re not wasting money heating a space that doesn’t need it.'
If you are going away over Christmas, it's best not to turn your heating off completely, especially if it's going to be cold. Instead, have it come on a couple of times at a lower temperature to prevent pipes from freezing.
4. Putting your thermostat in the wrong place
In order for your thermostat to control your heating most efficiently, it needs to be positioned correctly. If a professional installed yours, then it's likely that it is (although never hurts to double check). However, if you installed yours, or moved it from it's original position (which is not recommended) on a DIY basis, you may have got it wrong.
'The most common mistake we see when it comes to thermostats is incorrect placement,' reveals James Clark, Technical Training Manager at Wiser. 'Your thermostat should always be placed in a position where it can accurately respond to the temperature of the room, so must be away from radiators or other appliances which give off heat. Similarly, you should always make sure your thermostat is not in direct sunlight or placed in a draughty area either, or it won’t take an accurate reading.'
5. Sticking with a dated thermostat
If you have a thermostat that sets a single temperature for your whole home, including rooms you don't use as often as others, then you're likely paying for energy you don't need.
'Relying on a single thermostat for the whole home often means you are overheating rooms that are barely used. Bedrooms, spare rooms and home offices do not all need to be at the same temperature at the same time. Zoning or smart controls can help target heat where it is actually needed and cut unnecessary waste.'
Upgrading to a smart thermostat, like the Google Nest Learning Thermostat, (£95.28, without installation, from Amazon, or Hive Thermostat (£119 from Hive Home), can give you better control (you can control your heating from your phone), and allow you to zone you home to heat where you need when you need. It's crucial that you select a smart thermostat that is compatible with your heating system so do check carefully before you buy.
6. Having the wrong kind of thermostat
If you do want to upgrade your room thermostat, then it's important you choose one that is compatible with your specific system. Some work with conventional boilers, while others only work with combi-boilers for example.
'Not all thermostats work with all systems, so you need to make sure the one you choose is compatible,' says heating expert Stephen. 'Some thermostats are manual, while others are smart and can be controlled with your phone, so it’s worth deciding which will suit you best. It’s also worth checking whether you need professional installation, especially if the wiring in your home is complicated, or if you’re upgrading from an older model.'
You should take into account your lifestyle too. 'If your routine is the same every day, a simple programmable thermostat will be enough,' adds Stephen. 'But if your schedule changes regularly, a smart thermostat might be better, as it can learn your habits, be controlled remotely, and help you save more energy.'
7. Having your boiler thermostat too high
Many households with a combi-boiler won't realise that they actually have two thermostats in their home — a room thermostat and a boiler thermostat.
And having this boiler thermostat on too high is another energy-wasting mistake people are making. 'If you’re one of the 17m households with a Combi boiler it’s worth reducing the boiler thermostat down to 55°C - 60°C, this will ensure the boiler condenses more and increases its efficiency,' advises Martyn Bridges, Director of External Affairs at Worcester Bosch. 'If you have a Regular or Conventional boiler and a hot water storage cylinder then this isn’t an option as you need the thermostat to be relatively high to adequately and safely heat the hot water storage cylinder to over 60°C.'
FAQs
What temperature should your thermostat be set at?
For healthy adults, setting your thermostat between 18 and 21°C should be enough to keep you warm while also ensuring your boiler is working most efficiently. If yours is set at 21°C, then it's worth trying it at 20°C to see if you notice the difference in comfort. That 1°C reduction could save you £100 on your annual energy bill so is worth doing.
For babies and small children, as well as the elderly and those with health concerns, the temperature may need to be higher.
For more ways to keep warm at home, while keeping your heating bills as low as possible, try these home upgrades to keep the winter chill away.

Sarah Handley is Ideal Home’s Renovation Editor. She joined the team full time in September 2024, following three years of looking after the site's home finance content. As well as all things renovation, Sarah also looks after our Home Energy content, which covers all aspects of heating and insulation as well as tips on how homeowners can reduce their energy usage. She has been a journalist since 2007 and has worked for a range of titles including Homebuilding & Renovating, Real Homes, GoodtoKnow, The Money Edit and more.
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