Heat pumps

Heat pumps are a very efficient way of heating a property and in many cases can be a direct replacement for a traditional gas or oil boiler. By utilising the available energy in the ground or the air, a heat pump can use this to heat the house and/or the hot water. In addition to being cheaper to run than traditional boilers, they also emit much less carbon dioxide into the atmosphere.

It is very important that a heat pump system is designed and installed correctly as there needs to be a close relationship between the amount of energy required within the property, the size of the heat pump and the ability of the ground or air to provide sufficient low level energy. Unlike a traditional gas or oil boiler which can be oversized without major issue, a heat pump is most efficient and reliable when operated close to its maximum output.

There are a number of different types of heat pump:

  • Ground Source heat pumps use heat energy from the ground or a water source to produce hot water for heating and the cylinder
  • Air Source to Water heat pumps use heat energy from the ambient air to produce hot water for heating and the cylinder
  • Air Source to Air heat pumps use heat energy from the ambient air to heat the air in a property
  • Air Source Exhaust Air heat pumps use heat energy from within the home to produce hot water for heating and the cylinder
  • Air Source Absorption heat pumps use heat energy from the ambient air but the heat transfer process is gas driven rather than electric

There are different benefits to each of these types of heat pumps which we can discuss with you during the initial design stage. If you are looking to claim the government Renewable Heat Incentive payments then currently only the Ground Source and Air Source to water heat pumps qualify.

They all work on a similar principle:

  • Low level energy is captured from the air or the ground
  • This energy is transferred to a sealed circuit containing a refrigerant fluid that boils at a temperature similar to the captured energy which expands to a gas producing heat
  • The refrigerant gas is then further compressed which substantially increases the pressure and hence the temperature of the refrigerant (Boyle’s Law)
  • This high temperature energy is transferred to the heating/hot water system lowering the temperature of the refrigerant gas as it condenses
  • The expansion valve releases the pressure on the refrigerant lowering the temperature to below the air or ground temperature ready to be reheated
  • This process can continue indefinitely for as long as the heat pump needs to produce heat

There are also a number of different types of compressor used within a heat pump and the optimum type will depend on the heating requirement and schedule.