Air source heat pumps are a low carbon heating system that use the ambient air to heat up your home. They used for both hot water and heating. 

Air source heat pumps use the same kind of technology that keeps a fridge or freezer cool, but in reverse. Heat from the outside air is gathered and absorbed into a loop with refrigerant fluid. After the heat is extracted from the air it passes through a compressor. The compressor does as it sounds; it compresses, which results in a higher temperature.

Air source heat pumps use the same kind of technology that keeps a fridge or freezer cool, but in reverse.

1. Air is drawn into the air source heat pump from outside.
2. The air source heat pump absorbs the heat from the air and transfers the heat via a refrigerant to the water system in the home that provides heating and hot water. After the heat is extracted from the air it passes through a compressor. The compressor does as it sounds; it compresses, resulting in a higher temperature. This process uses electricity.
3. The heated water is circulated around the heating circuit and indirectly passed through the hot water cylinder as it would with a traditional boiler system. 
4. Hot water is stored in the hot water cylinder to be available for baths, showers and taps throughout the home.
5. The heated water is distributed through the home's heating system, such as radiators or underfloor heating and is then circulated back through the pump to be reheated.

Designs can vary, but air source heat pumps tend to comprise of a unit outside of the home and a hot water cylinder inside. The size of an air source heat pump unit will vary between manufacturers, but our designers ensure that the positioning of any system is carefully considered to ensure it will not impede on outdoor space or take away from the aesthetic of your Cala home.

As they work at a lower temperature than gas boilers, radiators will be marginally larger to ensure homes are heated thoroughly. Cala homes are expertly designed to take this into account and ensure that radiators tie seamlessly into your home.

Air source heat pumps generate far fewer carbon emissions and have an efficient conversion rate of energy to heat. They can be 200% - 400% efficient, which means that for every 1kW of electricity that is used, between 2 - 4kW of heat energy is produced. In contrast, a traditional gas boiler is typically around 85% efficient.

An air source heat pump can reduce the lifetime operational carbon emissions of a medium-sized home by around 90%. This equates to roughly 250,000 miles driven in an average car, or about 10 times around the earth.

What’s more, as the electricity grid is decarbonised further with renewable energy measures, heating and hot water production within the home will become even more sustainable.

Air source heat pumps use electricity, so they are naturally open to price fluctuations set by the market. However, when combined with a well-insulated home to retain heat and factoring in the lifespan, efficiency and low carbon impact of the system, there can be overall cost benefits when compared to a standard gas boiler.

Further, there are variable electricity tariffs on the market that can be better suited to heat pump users. These tariffs offer lower electricity prices during times of low electricity demand; this can make running your heat pump cheaper than a standard electricity tariff.

Externally, the actual heat pump unit generates very little noise. Air source heat pumps that are running correctly and maintained, emit around 40 decibels, similar to that of a fridge. 

You will also find less noise from pipes and radiators associated with traditional gas boilers, due to the way the heat pump system runs.

Even when temperatures reach 0°C and below there is still ambient heat available in the air to be used, with most models working fine down to -25°C. The heat pump will have to work harder, but even in winter it should still work twice as efficiently as a gas boiler. Air source heat pumps also include a heating boost if needed when the weather is particularly cold.

In some of the coldest countries on Earth - Norway, Sweden and Finland - about 40% of households have heat pumps.

Whilst it is not possible to run an air source heat pump directly off of solar/PV panels, it is possible to run the heat pump from battery power stored from solar/PV electricity generated.