An Air Source Heat Pump (ASHP) captures heat from the air circulating outside your property and boosts the temperature to provide heat and hot water. It is a very effective, low carbon way of heating your home and can be combined with a number of renewable and energy efficient technologies to deliver a truly sustainable home or commercial premises.

An ASHP can be installed in new and existing properties and the Government’s Renewable Heat Incentive provides cash payments for all eligible installations, which makes the investment even more attractive.

In warmer months ASHPs can operate as air conditioning units, meaning that you benefit from your heating system all year round, whatever the weather!

How air source works

An Air Source Heat Pump uses the same technology as your kitchen fridge to move heat from one place to another.

An ASHP uses the temperature of the air circulating outside to warm a liquid refrigerant.

The heat pump turns the refrigerant into a gas, compresses it and then condenses back into a liquid again which generates heat energy and the cycle starts again.

How air source works

What makes heat pumps sustainable?

The temperature of the air outside is determined by the sun and local weather conditions and is therefore a renewable source of heat.

Using this renewable energy to help heat your home is more sustainable than fossil fuel alternatives.

Heat pumps are electric, but by using heat from the air they use less electricity to produce heat than traditional electric heating systems.

Combining your ASHP with your own solar energy increases their sustainability and further reduces carbon emissions.

What makes heat pumps sustainable?

Are air source heat pumps efficient?

The efficiency and performance of an ASHP is measured using Coefficient of Performance (COP) and this varies by model and brand.

A number of factors including the insulation levels that your property has, your existing heating system and whether you are using under floor heating versus radiators will determine the overall performance of your ASHP.

Government incentive schemes to encourage investment in low carbon technology can currently cover the cost of installation and ongoing maintenance costs are lower than with traditional heating systems.

Geo Green Power have extensive experience and will ensure you understand the options available.

Are air source heat pumps efficient?

Learn more about how ASHPs work

If you choose Air to Air your ASHP will provide hot air to heat your property and you will need an alternative system to provide hot water.

If you choose Air to Water then your ASHP will provide hot water to heat your property and provide hot water for use within your home.

It’s important to consider your requirements and any unique aspects of your property and location to create the best solution.

When designed and configured correctly your ASHP does not require a back-up heating option.

Heat pumps are designed to maintain properties at a consistent temperature. This is when they run at their optimum efficiency and are most effective.

ASHPs can be combined with over-sized radiators or underfloor heating. Underfloor heating is often more efficient, but great results can be achieved with other forms of heating.

We will ensure that we recommend the right option for you and your property

ASHPs work all year round and in temperatures down to -15 degrees.

They are more efficient when the outside temperatures are higher, however in the UK the difference between seasons is very minimal.

All air that is above the temperature of absolute zero has heat energy!

In recent years ASHP technology has improved considerably. The cost of ownership has come down and the units have become quieter and more efficient.

Request a call to discuss your project

Isaac has been with Geo Green Power for 3 years, building our HVAC team and overseeing all of our heating projects. Request a call with Isaac to discuss your project.

What is the installation process?



ASHPs are fitted to the outside of your property and are about 1m wide, 1m high and around 30cm deep.

No ground works are required.


Depending on your existing system, your ASHP may easily link to your water tank and heating with limited additional works. You may need to replace your radiators for larger units.

A domestic installation in a single property is usually completed and commissioned within 5 working days.

Learn more about installation

ASHPs have very few moving parts and require less ongoing maintenance than traditional heating systems. We recommend an annual service to ensure that your system is running at its optimum efficiently.

You do not require planning permission for an ASHP.

Your ASHP is positioned outside your property and is best in a sheltered location which has good air flow. Most properties can easily accommodate an ASHP in a location that is both effective and convenient.

ASHPs work best when they are combined with other energy saving technology such as insulation and double glazing. Running your heat pump to maintain your property at a consistent temperature is also advisable.

Changing from Oil Fired Heating to Air Source

Changing from Oil Fired Heating to Air Source

When Paul took on a 1970s property he wanted to move away from oil fired heating. He carefully compared the cost of replacing the old oil boiler with an up to date condensing oil boiler or an Air Source Heat Pump system and found that the heat pump option was the right choice for him.

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Costs & Expected Returns

What is the installation cost for air source?

Our ASHP installations start from around £12,000

How much do ASHPs cost to run?

It’s very difficult to estimate the running costs of your installation as it will depend on the size of the space you want to heat, the temperature you are running the system at and a number of other factors such as insulation and whether you are using underfloor heating or radiators.

We will be happy to provide an estimate of your running costs if you would like to discuss your project.

What will my return on investment be?

The return on investment that you receive will be determined by the type of fuel you are looking to replace and the cost of running your system. Higher returns can be achieved when switching from oil or LPG heating systems.

The current Renewable Heat Incentive provides payments that, in a number of cases, can cover the cost of the installation.

Heat pumps require less maintenance and repair than most traditional heating systems, which also makes them an attractive investment.

Get in touch to discuss your ASHP project

James - Geo Green

James oversees all of our air source heat pump installations. Get in touch today to organise a no-obligation consultation about your next project.

What our customers say

What our customers say

ASHPs in Commercial & Domestic Buildings

ASHPs in commercial buildings

ASHPs can easily be installed in commercial premises to provide heating and air conditioning and are particularly efficient when running to provide a consistent temperature for offices and workspaces.

ASPHs in domestic houses

ASHPs provide a low carbon, energy efficient way of heating homes. The systems are low maintenance and combining them with other energy efficient technology helps to ensure that they perform at their best.

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ASHPs in New Builds vs Existing Properties

ASHPs installation in new builds

The construction of a new property is the perfect opportunity to consider and implement energy efficient, sustainable technology to ensure that the finished result is as cost effective and environmentally friendly as possible.

The UK Government is due to bring in the Future Homes Standard in 2025 which will prohibit any new build property from having a fossil fuel heating system.

Incorporating low carbon, renewable heating into new build projects will ensure that you remain ahead of legislation.

ASHPs installation in existing and historic buildings

ASHPs can be retrofitted into existing properties to replace oil, LPG and mains gas heating systems. The return on investment will vary depending on the existing heating system and other factors such as the property’s energy ratings.

Often an initial phone-based survey will provide all the information we need to be able to outline whether an ASHP is the right option for you. We can also discuss other low carbon options.

Air Source vs Alternative Heating Solutions

Comparing ASHPs to existing gas and oil systems

An ASHP provides an energy efficient, low carbon option when compared to gas, oil or LPG heating systems. It delivers a significant reduction in CO2 emissions and has lower ongoing maintenance costs.

The costs of installation may be higher than traditional fossil fuel systems, but this is offset considerably by the RHI payments you will receive.

Running costs are usually comparable to mains gas systems, and significantly cheaper than oil or LPG.

Air source heat pump or ground source

An ASHP installation is often cheaper and less intrusive than a GSHP installation and is ideal for smaller properties and those with limited outside space.

If you have a large property to heat, and enough outside space a GSHP will outperform an ASHP. A GSHP system can collect more renewable heat from the earth and therefore requires less electricity to produce the same heat output.

Air source heat pump or solar panels

When considering an ASHP or solar panels, the best choice for you will depend on your heating requirements, budget and energy usage and we will be happy to discuss your options with you.

It may be most cost effective for you to consider a scheme that incorporates both. Using solar power to run your heat pump could deliver the greatest cost efficiency and deliver the most sustainable scheme.

Find out more about renewable energy…