Many are looking for alternative home heating options in a climate of increasing fuel bills. As a result, air source heat pumps are growing in popularity. Here we explain everything you need to know about air source heat pumps, including buying or selling a property with this heating method.
What is an air source heat pump?
Typically, a home’s heating system either burns fuel to create heat or converts electricity into heat. An air source heat pump doesn’t do this. Instead, it resembles a reverse air conditioning unit or fridge. They take heat energy that is already outside the building and brings it into your home.
Air from outside blows over several tubes filled with refrigerant, heating it and converting it from a liquid into a gas. Then, the gas moves through a compressor, increasing the pressure, which adds more heat. Next, the hot gas passes through a heat exchanger, surrounded by water (air-to-water air source heat pump) or air (air-to-air air source heat pump). Most systems in the UK are air-to-water. The heated water or air then travels around your home, providing heating and, if air-to-water, hot water. As the refrigerant cools, it condenses, ready for the cycle to begin again.
As such, air source heat pumps are more efficient; the heat they produce is greater than the energy they use. Therefore, they are more fuel and cost-efficient, making them better for your wallet and the environment (subject to the insulation qualities of a specific property.)
Is an air source heat pump a good idea for your home?
There are some factors to consider with air source heat pumps.
Air source heat pumps must work harder when there’s a greater difference between outside and inside temperatures. This means that they are more effective with underfloor heating rather than radiators. Underfloor heating allows less direct heat to create the same ambient warmth. Using radiators with an air source heat pump will probably need larger ones than boiler-fed radiators.
Additionally, air source heat pumps are best for gradual and ongoing heating. It takes a mental shift. If you’re feeling the chill, you can’t just whack up the heat, as it’s a slower process. The output is less than you’d get from a boiler. You need to take a more consistent approach to maintain ambient heat.
You can use an air source heat pump to heat hot water, but you won’t achieve the same hot temperatures as a standard boiler. For example, if your household enjoys regular baths, you may need a larger hot water tank.
Air source heat pumps are excellent for efficiently heating most homes. They emit zero carbon (because they don’t burn fuel), and you can take advantage of different grants and schemes to make installing them cheaper. Unlike ground source heat pumps, there’s no disruption to your garden through installation or maintenance. Air source heat pumps are lower-maintenance overall. You may even be able to reverse the system for cooling in summer.
However, if you choose air source heat pumps, you will need enough room outside for the unit and inside for a good-sized water storage tank. Additionally, installing any new heating system is costly, so consider savings over years rather than months. However, they can be worth considering if you are completing a new build, considering underfloor heating, replacing LPG or oil heating, or adding an extension. It’s always worth improving your home insulation to get the best return on how you heat your home. High quality insulation is essential with heat pumps in order to maintain a consistent ambient temperature otherwise the hot air will escape into the outside making the units work harder and cost more to run.
