As the autumn leaves start to fall and the winter chill sets in, lots of people rely on their heating to stay cosy at home. But what if you use an air source heat pump (ASHP) to heat your home or provide hot water?
With the government's ambitious target to install a further 600,000 a year by 20281, heat pumps are set to grow in popularity across the UK. Air source heat pumps work by extracting heat from the outdoor air, which means a lot of people will be thinking “does a heat pump work in winter?”. The short answer is yes, but there’s a few things you can do to ensure you maintain maximum efficiency across the winter months.
We’ve put together a guide on handy tips and tricks to look after and improve the efficiency of your heat pump in the cold weather.
How do air source heat pumps work in winter?
The average temperature in the UK is between 2-7°C in the winter months2, but heat pumps still work in temperatures as low as -20°C. So there’s no need to worry about your heat pump not working in the cold weather.
Understanding heat pump operation.
The theory behind ASHPs is actually quite simple once you break it down. Think of an ASHP like a fridge but in reverse, rather than keeping things cold on the inside an ASHP grabs the warmth from the air outside, converts it and then pumps all that glorious heat into your home. Even when it’s chilly, there’s enough heat in the air outside for it to work inside.
Learn about how heat pumps work.
The role of refrigerants.
Refrigerants are incredibly important, because without them your heat pump just wouldn’t be able to work!
In a nutshell, use ‘liquid to gas, and back’ as a saying to remember what a refrigerant does. Refrigerants start off as a liquid, but they have an extremely low boiling point. As the outdoor air comes into contact with the system, the heat in the air causes the refrigerant to evaporate and become a gas. The gas is then passed through your heat pump, where the heat is extracted. This turns it back into a liquid, ready to start the cycle again.
Due to refrigerants having such a low boiling point, even the winter air will still contain enough heat to boil them into a gas.
Preparing your heat pump for winter.
Although the temperature may drop, your trusty ASHP can certainly handle it. There’s actually more heat pumps in colder countries like Norway and Finland than anywhere else in Europe3, so the relatively mild UK climate is easy to manage.
Your heat pump will continue chugging along even when the temperature drops well below freezing. In the UK we’re lucky with the weather (not something you hear often) as it rarely drops below a teeth chattering -20ºC - but if it does your heat pump might need a little help to keep you warm.
If you live in an area where these extreme temperatures may be possible, consider investing in a backup heating system, like electric heaters or radiators, that you could use in an emergency.
It's also important to prepare, inspect, and clean your heat pump more regularly in the winter months. This is because there’s a higher risk of dirt and debris getting caught in your ASHP when it’s wet and windy.
Maintenance tips for winter.
Scheduling professional servicing.
Just like a boiler, heat pumps should be serviced annually to keep them running in tip-top condition. Try scheduling your service ahead of winter if possible, so any issues can be fixed before the cold sets in.
Common issues and troubleshooting.
The main problem ASHP owners face in winter is when ice begins to build up in the pump itself, which could potentially decrease efficiency. To combat this, make sure you regularly complete your checks and inspections. We recommend popping your heat pump on the third setting (de-icer setting) as soon as you notice the temperature changing to below 0°C.
However, if you don’t have this setting there’s no need to worry. Just contact your installer and they’ll give you further instructions on what to do.
Heat pump features to look out for:
De-icing setting. This means you won’t have to worry about your heat pump when the temperature drops, because it will look after itself.
Variable speed compressor. This is when your heat pump can adjust its speed to meet the heating demands of your home, so you’ll never be waiting around for the heat to kick in.
High Heating Seasonal Performance Factor (HSPF). This feature can provide more heat output for less energy input, which is both cost effective and environmentally friendly.
Compatibility with your smart thermostat if you have one.
Maximising efficiency of heat pumps in cold weather.
Since you've invested in a heat pump, you naturally want to ensure it operates efficiently and delivers optimal performance, regardless of the weather. So here’s just a few things you can do to maximise your heat pump's efficiency.
Improving insulation in your home.
To ensure you get the most out of your ASHP we recommend proper home insulation. Not only are you pumping the hot air in, you’ll be making sure it’s not flying right back out again! There are a range of grants and schemes you may be eligible for to help you manage the costs of insulating your home.
Learn more about insulating your home.
Using smart thermostats.
Another thing you can do is use a smart thermostat to control your heating. Using smart thermostats gives you the control to maintain the temperature of your home remotely which will help you save money and energy by ensuring the heating is only on when it needs to be. Some can even manage your heating automatically by connecting to your smartphone to detect when you leave or return home.
Upgrade your heating with an air source heat pump.
Embrace the warmth and comfort of a heat pump, knowing it will keep you cosy even when the temperature drops. Upgrading to a heat pump is up to 4 times more efficient than gas boilers.4 Experience the benefits of a heat pump for yourself.
Heat pumps in a nutshell.
Find out what a heat pump is, how they work and why they’re better for the environment than older heating systems.