How Do Air Source Heat Pumps Work?
Posted on March 13th, 2026
❄️☀️ How Do Air Source Heat Pumps Work?
A simple guide to one of the most efficient heating technologies in the UK
Air source heat pumps (ASHPs) are becoming one of the most popular ways for UK homeowners to heat their homes more efficiently. They’re clean, low‑carbon, and can significantly reduce heating bills — but how do they actually work? The answer is surprisingly straightforward.
🌬️ They Capture Heat From the Air
Even on a cold day, the outside air contains usable heat.
An air source heat pump draws in this air and uses a refrigerant to extract the heat energy from it. This process works even in temperatures as low as –15°C.
🔄 The Refrigerant Cycle Does the Hard Work
Here’s the clever part:
- Air is pulled over a heat exchanger
The refrigerant absorbs heat from the outside air. - The refrigerant is compressed
Compressing it raises its temperature — just like how a bicycle pump gets warm when you use it. - Heat is transferred into your home
The hot refrigerant passes through another heat exchanger, releasing heat into your radiators, underfloor heating, or hot water cylinder. - The refrigerant cools and the cycle repeats
It returns to the outdoor unit to collect more heat.
This loop is continuous, efficient, and fully automated.
⚡ Why They’re So Efficient
Air source heat pumps don’t create heat — they move it.
That’s why they can achieve efficiencies of 300–400%, meaning:
- For every 1 unit of electricity they use
- They can produce 3–4 units of heat
This is far more efficient than a gas boiler, which can only reach around 90%.
🏡 Perfect for Modern, Low‑Carbon Homes
Air source heat pumps work best with:
- Well‑insulated homes
- Larger radiators or underfloor heating
- Consistent, steady heating rather than short bursts
They’re ideal for homeowners looking to cut carbon emissions and future‑proof their property.
🌍 The Environmental Benefits
Switching to a heat pump can:
- Reduce your home’s carbon footprint
- Lower reliance on fossil fuels
- Support the UK’s net‑zero goals
- Improve indoor comfort with stable, even heating
Pairing a heat pump with Solar PV makes the system even greener and cheaper to run.
🔧 WYGS Ltd: Your Local Heat Pump Specialists
At WYGS Ltd, we design and install air source heat pump systems tailored to your home. Our accredited engineers ensure maximum efficiency, and we help you access available government grants to reduce upfront costs.
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