If you’re considering switching to a more energy-efficient heating system, you’ve probably come across air source heat pumps. But how exactly do they work? Are they worth the investment? And can you get financial help for installation?
In this guide, we’ll break down everything you need to know about air source heat pumps, including how they work, their benefits, and the support available through initiatives like the Boiler Upgrade Scheme.
Air source heat pumps (ASHPs) are an energy-efficient alternative to traditional heating systems, providing warmth and hot water by extracting heat from the outside air—even in cold temperatures. They work much like a refrigerator but in reverse, transferring heat rather than generating it from fossil fuels.
There are two main types of air source heat pumps:
Air-to-water heat pumps – These transfer heat into your central heating system, warming your radiators, underfloor heating, or hot water supply.
Air-to-air heat pumps – These blow warm air directly into your home but don’t provide hot water.
Both options are efficient, but most UK homeowners opt for air-to-water systems as they integrate with existing heating infrastructure.
The process can be broken down into four key stages:
Heat Absorption – The heat pump draws in air from outside and passes it over a refrigerant fluid. The fluid absorbs heat from the air, causing it to evaporate into a gas.
Compression – The gas is compressed, raising its temperature significantly.
Heat Transfer – The high-temperature gas transfers heat to your home’s heating system (radiators, underfloor heating, or hot water supply).
Recycling the Refrigerant – The gas cools, turning back into a liquid, and the cycle starts again.
This constant process ensures a steady supply of heat, even in winter.
Switching to an air source heat pump offers multiple advantages, both financially and environmentally:
Lower Energy Bills – ASHPs are up to 400% efficient, meaning for every unit of electricity they use, they generate up to four units of heat. Compared to gas or oil boilers, this can significantly reduce running costs.
Reduced Carbon Footprint – Since they use renewable heat from the air, they produce far fewer carbon emissions than fossil fuel boilers.
Government Grants and Incentives – Homeowners may qualify for funding under the Boiler Upgrade Scheme, making installation more affordable.
Year-Round Use – Many ASHPs can also provide cooling in summer, making them a versatile solution.
Minimal Maintenance – With proper servicing, ASHPs can last 20 years or more, requiring little upkeep.
While air source heat pumps are an excellent heating solution, their efficiency depends on a few factors:
Insulation – Well-insulated homes retain heat better, maximising efficiency. If your home has poor insulation, you may need to improve it first.
Radiator and Heating System Compatibility – ASHPs work best with low-temperature heating systems, such as underfloor heating or large, modern radiators.
Outdoor Space – The external unit needs adequate space for airflow—usually around 1m² on an external wall or the ground.
If you’re unsure whether your home is suitable, it’s best to speak with professional air source heat pump installers for an assessment.
Another option to consider is exhaust air heat pumps (EAHPs). Unlike traditional ASHPs, these extract heat from indoor air that would otherwise be lost through ventilation. They are particularly effective in well-insulated homes and offer an all-in-one solution for heating, hot water, and ventilation.
If space is limited or you’re looking for a self-contained system, an EAHP might be a better fit.
If you’re looking to switch to a more energy-efficient heating system, the Boiler Upgrade Scheme (BUS) can help make air-source heat pumps more affordable. This government-backed initiative offers £7,500 towards the cost and installation of an air source or ground source heat pump, significantly reducing upfront costs. To qualify, your property must be in England or Wales, have a valid Energy Performance Certificate (EPC), and fully replace an existing fossil fuel or electric heating system. Unlike other grants, there are no restrictions based on location, making it widely accessible. While the Warm Homes Grant will be available from 2025, it applies only to a very limited number of households. For more details on eligibility and how to apply for the Boiler Upgrade Scheme, contact our team—we’re happy to guide you through the process.
Choosing the right air source heat pump installers is just as important as choosing the system itself. A poorly installed system can reduce efficiency and increase energy bills.
At Alternative Heating Solutions, we’re HeatGeek-trained, MCS-accredited, and experienced in installing ASHPs for homeowners across Essex and beyond. We provide:
Air source heat pumps are a game-changing alternative to traditional heating, offering low running costs, reduced carbon emissions, and government-backed financial support.
If you’re ready to future-proof your home and take advantage of funding like the Boiler Upgrade Scheme, contact Alternative Heating Solutions today. Our expert team can help you find the best heating solution to keep your home warm, efficient, and cost-effective for years to come.
