The best way to pay for energy
28 Mar 2024
An air source heat pump is an alternative way to heat your home. It will enable you to generate your own renewable heat and potentially save you money on your energy bills in the long run.
They deliver heat at lower temperatures than gas and oil boilers, so you'll need to run them for longer periods to heat your home to a comfortable temperature.
A well-insulated home is essential – otherwise, the heat generated by the pump escapes more easily and you may find the temperature doesn't get up to a level you're used to.
A heat pump could save more on your heating bills, but this will depend on whether you're replacing an expensive system – such as electric storage heaters, oil, LPG (liquefied petroleum gas) or coal – along with how efficiently your heat pump is running, and whether or not you're on a heat pump tariff.
Here are some of the key advantages and disadvantages:
Note that many of these cons can be mitigated with correct setup, and are mainly just points to be aware of.
An air source heat pump takes heat from the outside air and boosts it to a higher temperature using a compressor. It then transfers the heat to the heating system in your home.
They work a bit like refrigerators in reverse.
The pump uses electricity to run, but it should use less electrical energy than the heat it produces. This makes it an energy efficient way to warm your home.
Air source heat pumps work even if the temperature is well below zero.
Ground source heat pumps also harness natural heat and increase the temperature to warm your home. Find out how ground source heat pumps work.
An air source heat pump is a low-carbon way of heating your home. They absorb latent heat from the outside air and use it to increase the temperature inside your home.
Air source heat pumps look similar to air-conditioning units. Their size depends on how much heat they'll need to generate for your home – the more heat, the bigger the heat pump.
There are two main types of air source heat pumps: air-to-water and air-to-air. They work in different ways and are compatible with different types of heating systems.
Air-to-water heat pumps take heat from the outside air and feed it into your wet central heating system.
They're most suitable for homes with larger radiators or water underfloor heating because the heat they produce is cooler than that from a conventional gas or oil boiler. To be most effective, they need a large surface area to release the heat.
It is more straightforward to incorporate larger radiators or underfloor heating for a heat pump while you're extending your home or in a new-build property. It can also cost less than retrofitting underfloor heating later on.
Air-to-air heat pumps take heat from the outside air and feed it into your home through fans. You need a warm-air circulation system to move the heat around your home.
These systems cannot produce hot water, so you'll need a separate immersion heater or other water-heating system.
In the summer, an air-to-air heat pump can operate in reverse. In other words, you can use it like an air-conditioning unit to provide cool air for your home.
If you're looking for an air conditioner, check our air conditioner reviews – just be aware that they can be energy-guzzlers and you should aim to pick one that uses energy efficiently.
Air source heat pumps are usually positioned outdoors at the side or back of a property. They need plenty of space around them for air to circulate.
You will either have:
You don't need a hot-water storage cylinder if you choose to install a heat pump for heating only (to heat your radiators/underfloor heating) and use a separate method for hot water (such as an electric shower, instant hot water taps or instantaneous hot-water unit)
Air source heat pumps are less disruptive to install than ground source heat pumps, as they do not require any digging in your garden.
Speak to your home insurance provider to check if your policy will cover the changes to your heating system.
If you're getting an air source heat pump, it's important to make sure that your home is well-insulated so that it can retain the heat. Underfloor heating or larger radiators are often installed alongside heat pumps to disperse the heat better.
Your installer should tell you how to use the controls for your heat pump to help you use it most effectively. You will probably need to heat your home for more hours but at a lower temperature.
When your system is completed, you should get a Commissioning Certificate from the installer. You should also get a Microgeneration Certification Scheme (MCS) installation certificate once the system has been registered (the installer must do this within 10 days). You'll need this to qualify for most funding schemes.
A typical heat pump should generate 2.5 to 4 units of heat for each unit of electricity it uses, in effect making heat pumps 250% to 400% efficient. The Coefficient of Performance can be even higher than this, though it can also be lower, especially in the depths of winter.
The Seasonal Coefficient of Performance (SCOP) tells you the average efficiency of your heat pump across the whole heating season. Your installer should calculate this and give you an estimate of SCOP before installing your heat pump. This gives you a realistic view of costs and efficiency that accounts for the accumulative warm, mild and cold days we face during the autumn and winter.
To get the best from your heat pump, you'll need to know how to use it most effectively. Often, you'll need to set your heating to come on for longer than with a traditional system. Your installer should show you how to control your heat pump system.
You should also have your heat pump serviced every two to three years. Check that any grills are free of leaves and debris on a regular basis, and follow any other maintenance checks advised by your installer.
An air source heat pump system can help to lower your carbon footprint as it uses a renewable, natural source of heat – air. How much CO2 you'll save depends on the fuel you are replacing. For example, the figure will be higher if you are replacing coal or an oil boiler, rather than natural gas.
A heat pump needs a power source – usually electricity – to power the heat pump, so there will still be some resulting CO2 emissions, but much less than from using a gas boiler.
Find out how to calculate your heat pump running costs to see what efficiency you need to save money versus running a typical gas boiler.
You'll need an MCS-certified installer who can apply for government grants on your behalf.
If possible, get multiple quotes for a heat pump installation because the costs may differ and recommendations may vary between assessors.
Energy companies offering heat pumps and installations include:
If you prefer to use a private installer, MCS hosts a database of MCS-certified contractors.
These installers agree to follow a code of conduct known as RECC (Renewable Energy Consumer Code). This means they should not use high-pressure selling techniques, misrepresent the benefits of a heat pump in your home or offer you better rates if you do marketing work for them.