Air source heat pumps absorb heat from the outside air for use in a household. It converts the energy created by the outside air into heat, giving a comfortable temperature inside the home and reducing heating costs by an average of 50% compared to traditional heating systems. Air source heat pumps are an alternative low cost solution for space heating and hot water.
Exhaust air heat pumps provides hygienic air inside the home. It also recycles heat energy that it captures from lighting, people and domestic appliances. The system covers the majority of the heating requirements in a very economical manner; therefore the existing heating system only needs to cover the peak periods.
It can be used to heat water for radiators, under floor heating systems or to warm the air in your house.
How it works
The air source heat pumps work in a similar but reverse way to a refrigerator in the way that it extracts heat from the outside air for use. It can extract heat from the air even when the outside temperature is as low as minus 15oC.
The air-source heat pump consists of an evaporator coil which absorbs heat from the outside air. It also contains a liquid called refrigerant which has a low boiling point. As the refrigerant reaches the evaporator coil it evaporates. From this the vapour is compressed by a compressor which results in a high increase in temperature. This is then fed to the boiler so that the refrigerants energy is passed onto the boiler water, to be heated. The evaporated refrigerant can also be used to heat the air.
There are two different types of air source heat pumps:
- An air-to-water system which uses the heat to warm water. The water can be used to pre-heat water in a storage tank or circulate through under floor heating or radiators. Heat pumps heat water to a lower temperature than a standard boiler system would, so they are more suitable for under floor heating systems than radiator systems.
- An air-to-air system produces warm air which is circulated by fans to heat your home.
Some systems are also designed to work in reverse as well, cooling the interior of a house in hot weather.
Benefits
- Reduces carbon dioxide emissions dramatically.
- Air is free so after initial costs bills would be greatly reduced.
- Minimal maintenance, storage and operating costs.
- Eliminates fuel bills as ground source heat pumps run on electricity, so there"s no need to pay for gas, oil or solid fuels to heat your house.
Installation and where it can be used
The air source heat pumps can be installed anywhere, particularly where it is not possible to drill a borehole or lay surface absorbers for a ground source heat pump. The systems generally complement the more traditional heating systems, and typically deliver about 80% of the space heating and hot water requirements for a house, while the traditional system delivers the rest on the coldest days.
The pumps should be installed outside the house but as close as possible to the building to prevent heat loss.