Air Source Heat Pump

Heat pumps are among the most efficient heating and hot water systems available today. Approximately 75% of the energy needed for heating comes from the environment. So for every 1kWh of electricity used to power the heat pump compressor, between 3 and 4 kWh of heating energy is produced.

How a Heat Pump Works

• A large quantity of low grade energy is absorbed from the environment and transferred to the refrigerant inside the heat pump (evaporator). This causes the temperature of the refrigerant to rise (even in sub zero temperatures) causing it to change from a liquid to a gaseous state.
• The refrigerant is then compressed, using an electrically driven compressor, reducing its volume but causing its temperature to rise significantly.
• A heat exchanger (condenser) then extracts the heat from the refrigerant to heat water for central heating, underfloor heating or domestic hot water.
• After giving up its heat energy the refrigerant turns back into a liquid and, after passing through an expansion valve, can once again absorb energy from the environment, allowing the cycle to being again.

Benefits:

• Even cold air is full of energy and air source heat pumps use the freely available heat in the ambient air to provide efficient heating and hot water at air temperatures as low as -25 degrees C. They also have the advantage over ground source, of lower installation costs because they do not require any groundworks.
• Can be utilised all year round between + 25 degrees C and -25 degrees C.
• Always available - an inexhaustible source of heat.
• Can be used for heating, domestic hot water and swimming pools.

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