How does an air source heat pump work?
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 on the same principle as a fridge or freezer - moving heat from one place to another.
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The air source heat pump absorbs heat from the outside air into a liquid refrigerant at a low temperature.
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Using electricity, the pump compresses the liquid to increase its temperature. It then condenses back into a liquid to release its stored heat.
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In a wet system, this heat warms up water to be sent to your radiators or underfloor heating. The remainder can be stored in your hot water cylinder.
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You can use your stored hot water for showers, baths and taps.
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In a dry system, this heat is circulated as warm air through ducts and vents. Air-to-air heat pumps can circulate either hot or cold air.
Heat pumps use electricity to run, but they are more than 100% efficient. This means they produce more heat energy in kWh than they use in electricity. This makes it an energy efficient way to warm your home. By contrast, gas boilers consume more energy than they put out into your home. Modern condensing gas boilers are labelled between 92-94% efficient. Boilers installed before 2005, when new regulations came in, are significantly less efficient.
Air source heat pumps work even if the temperature is below freezing (zero degrees Celsius) because there is heat energy present in air at any temperature above absolute zero (-273 degrees Celsius).