An air source heat pump absorbs heat from the outside air and is an environmentally friendly alternative to a traditional boiler.
If you’re looking to install a renewable heating system in your home, you should consider getting an air source heat pump. Although relatively new in the UK market, an air source heat pump could be the ideal solution for generating your own heat, reducing your carbon footprint and saving money on your energy bills.
But what exactly is an air source heat pump, and how does it work? This article includes answers to these questions and will help you determine whether your property is suitable for an air source heat pump.
What is an air source heat pump?
An air source heat pump is a renewable heating source that takes warmth from the air outside and uses it to heat your home, even when it’s freezing outside. The energy an air source heat pump produces is renewable because it uses air heated by the sun and a bit of electricity to heat your home and water.
Air source heat pumps are widely known for being one of the most efficient heating solutions available to replace domestic gas boilers, which release carbon emissions into the environment and contribute significantly to climate change.
How does an air source heat pump work?
An air source heat pump looks much like an air-conditioning unit and has to be positioned outdoors, usually at the side or back of your home. The technology an air source heat pump uses is similar to that in your fridge or freezer, but it works a bit like these appliances in reverse. It also uses electricity to operate.
When sited outside a property, an air source heat pump pulls in air and passes it into a liquid refrigerant. The pump uses electricity to compress the liquid and increase its temperature, turning it from a liquid into a gas. This gas then passes through a compressor and heats up before being transferred into your home’s heating system. When the gas cools, the refrigerant turns back to a liquid and starts the cycle again.
Air source heat pumps require only a small amount of electricity to run and should use less electrical energy than the heat they produce, making them an energy-efficient way to heat your home. If you’re wondering how an air source heat pump performs in cold weather, it will continue to work even when the temperature is well below zero, as long as you purchase the correct size pump for your home and needs.
Are there different types of air source heat pumps available?
Yes. The two main types are air-to-water and air-to-air heat pumps. They both rely on electricity and are highly efficient heating solutions, but they work differently.
Air-to-water heat pumps
Most homeowners in the UK opt for an air-to-water heat pump because it can extract heat from the air outside and feed it into a wet central heating system. When an air-to-water heat pump is sized and installed correctly with a hot water cylinder, it can give you central heating and hot water when you need it.
Air-to-air heat pumps
Unlike an air-to-water heat pump, an air-to-air system pumps heat from the air outside and feeds it into a property through fans, meaning a warm air circulation system is required to move the heat around a home. Another difference between the two heat pumps is that an air-to-air heat pump can provide heating and cooling, depending on the season. However, it cannot produce hot water, so you need to find another way to heat water for taps and showers.
Is my property suitable for an air source heat pump?
Air source heat pumps are perfect for well-insulated, energy-efficient homes that keep heat in and warm up fast. They have a lower output than gas and oil boilers and cannot deliver heat as quickly, meaning you will likely need to heat your home for longer at a lower temperature.
Because they produce heat at a lower temperature than a traditional heating system, air source heat pumps sometimes require large radiators and underfloor heating to help the heat disperse better. So, if you want to switch from a gas boiler to an air source heat pump, you will probably have to purchase larger radiators for your home.
If you live in a property off the gas grid and currently use oil, LPG or electricity for heating, an air source heat pump is ideal as it will be one of the most efficient ways to heat your home.
It’s worth remembering that air source heat pumps do not take up much space because the unit sits outside your property, but this also means you will need enough room for it to be placed on the floor somewhere outside your home.
What are the pros and cons of an air source heat pump?
The advantages and disadvantages of an air source heat pump include:
Advantages
- Significantly lower carbon footprint than conventional heating solutions
- Highly efficient and can be used for heating and hot water
- Some air source heat pumps can provide cooling in the summer
- The average life expectancy of an air source heat pump is between 15 and 20 years
- Low maintenance
- Easier to install than a ground source heat pump
- You could save money on your heating bills
- You could receive a grant of £5,000 towards the installation through the government Boiler Upgrade Scheme
Disadvantages
- More expensive than a gas boiler, but government support is available from April 2022 to April 2025
- You need to have enough space outside your property for the external unit
- Your property needs to be well-insulated so that it can retain the heat
- You may need to make changes to your home, such as fitting larger radiators
- An air source heat pump requires some electricity to run unless you generate electricity from a renewable source, like solar panels
What government grants are available for air source heat pumps?
The typical cost of installing an air source heat pump is between £5,000 and £11,000, but you may have to fork out more, depending on your needs. However, the government is currently offering financial help for homeowners who switch to low-carbon heating systems, like air source heat pumps, as part of the Boiler Upgrade Scheme.
Administered by Ofgem, the Boiler Upgrade Scheme came into effect on the 1st of April 2022 and will run until April 2025. The UK government is now offering £5,000 grants to encourage property owners to replace their fossil fuel boilers and help households install air source heat pumps (and other low-carbon heating solutions) at a discounted price.
So, if you want to get rid of your gas boiler and install an air source heat pump at a fraction of the price, the Boiler Upgrade Scheme grant could help you do just that.