Home » Air to Water Heat Pump

Air to Water Heat Pump

An air to water heat pump is a straight forward install when compared with ground source heat pump. The air to water heat pump system takes heat present in the outside air which is then transferred to your wet central heating system through a heat exchanger. Like any other conventional heating system the insulation value of the property is most important when it comes to the heat pumps performance and efficiency levels.

An air to water heat pump delivers low temperature heat over a longer period of time when compared to oil or gas heating systems, which a much higher operating temperature but are a lot less efficient. This low temperature operation makes an air to water heat pump an excellent choice for underfloor heating system. Alternatively larger radiators can be used if underfloor heating is not in place. Aluminium radiators are also available and are a superb pairing with air to water heat pumps. They have a low water content and a quicker heat up time making them an excellent choice heat emitter.

An air to water heat pump system can be either Monobloc or split with split being the most popular choice for new builds

Monobloc Heat Pump

The Monobloc consists of a single unit in which the compressor, condenser and heat exchanger is housed. It is sited outside of the property and the only plumbing connections required are the primary flow and return piping from the wet central heating system. Because the Monobloc is a single unit no refrigerant handling will be required. Dependent on the air to water heat pump installed glycol may be required due to the possibility of freezing conditions. The Monobloc heat pump unit is ideally suited for retrofit installation where the current heat source is either gas or oil.

Split System Heat Pump

A Split system is when the compressor is placed outside with the heat exchanger unit placed inside the dwelling. Refrigerant piping from the outdoor unit to the indoor unit will be required. These refrigerant gas lines will be site built and refrigerant handling is required. The split system is ideally suited to new builds or major renovations although they can be installed in retrofits the additional works required may not be a cost effective option in comparison to the Monobloc system.

The Panasonic Aquarea Air Source Heat Pump Explained



Benefits of an Air to Water Heat Pump

  • Cheaper and easier to install than a ground source heat pump system
  • Can Provide for both space heating and hot water requirements
  • Lower carbon emissions than conventional systems
  • Little maintenance is required
  • No Fuel Delivery’s needed
  • Improves BER rating
  • Ideal solution for retrofit installation
  • Lower fuel bills


Location of air to water heat pump

Do you have a suitable location for the air to water heat pump to be situated, it can be either placed on the ground surrounding the property or mounted to a suitable wall or roof. If you choose to wall or roof mount your air to water heat pump it must be kept minimum of 500mm from the edge of the wall or roof to comply with planning conditions. Noise level must also be considered when choosing a suitable location for your air to water heat pump. Although relatively quiet in operation consideration must be applied to noise levels at the party boundary. These Levels must not exceed 43db as per planning regulations. When in operation the air to water heat pump will expel relatively cool air this needs to be taken into consideration also.

Property Insulation Value/Heat Pump Performance

Is your property insulated to a high degree? Air to water heat pumps work best when producing a low level of heat energy to your central heating system. For optimum heat pump performance the maximum design temperature of the heating system should be no more than 45°C. This temperature is a lot less than a traditional boiler system and therefore it is essential that your property is well insulated for an air to water heat pump to be truly effective.

panasonic heat pump installed outside