What is an air source heat pump?

What is an air source heat pump?

Air source heat pumps are a sustainable alternative to traditional fossil fuel heating systems and with their green credentials and high efficiency operation, they are playing a major role in helping the country achieve its net zero carbon emission targets.

Types of air source heat pumps
There are two types of air source heat pumps - air-to-air heat pumps and air-to-water heat pumps. Air-to-air heat pumps take heat from the outdoor air and transfer this heat into the air within a home via fan coil units located in each room. It is important to note that these types of heat pumps do not heat water. Meanwhile, air-to-water heat pumps can fulfil both the space heating and hot water requirements for a home.

Air-to-Water heat pumps
An air-to-water heat pump takes heat from air outside and transfers this into water. Grant heat pumps are 'air to water' systems and they capture heat energy from the air outside and transfer this into 'wet' heating systems such as radiators or underfloor heating. These heat pumps also heat water stored in a cylinder which then supplies hot water to the home as well. 

Monobloc Units and Split Units
A monobloc air source heat pump is supplied as a single outdoor unit, factory assembled with no onsite refrigerant filling required. Meanwhile, split system heat pumps are supplied as two separate parts (outdoor fan unit and indoor hydro unit) and must be connected onsite with suitable pipework and filled with refrigerant by a F-gas qualified installer.

How do air source heat pumps work?
In brief, air source heat pumps utilise the heat energy in the air and convert it into useable energy to heat homes. Grant’s Aerona³ heat pumps are monobloc units and they use a vapour compression cycle which is the same as that used to extract heat from a domestic fridge.

The heat pump draws air in and transfers it over an evaporator where R32 refrigerant is exposed to this air. The liquid refrigerant, which has a low boiling point, boils off to a gas and absorbs the latent heat energy within the air. The gas is then compressed which increases the heat content in the refrigerant before passing through a heat exchanger. Here, the gas condenses back to a liquid while transferring the heat to the water of the heating system. The liquid refrigerant is then re-circulated through the evaporator and the cycle is repeated.

The system water which has been heated up then exits the rear of the heat pump via flow and return pipework and is circulated throughout the rest of the central heating to provide space heating and hot water within the home.

To learn more about what living with a heat pump is like, please visit our YouTube channel. 

Can heat pumps be integrated with other renewables?
Yes, heat pumps can either be installed on their own (alongside a suitable hot water cylinder) or they can be installed alongside other renewable technologies such as a solar thermal system. By combining technologies, you can maximise your carbon savings while also reducing your energy bills. Read our blog to discover more about combining heating technologies.  

Please click here to read more about Grant's Air Source Heat Pump range.

What is an air source heat pump?
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