Air source heat pumpscome in two different varieties. More frequently, air-to-water systems heat water that is subsequently distributed throughout the house via radiators or an underfloor heating system. They can also be used to warm water that is stored for use in the kitchen or bathroom. Since they cannot heat water, air-to-air systems often use fans to move heated air throughout the house.
How do they work?
The same technology that keeps your refrigerator cool is used by air source heat pump, but in the opposite direction. Between two heat exchangers, a liquid refrigerant with an extremely low boiling point is circulated in a loop. This refrigerant absorbs heat energy from the ambient air temperature outside and warms up to become a gas. The temperature of this gas is then raised by its subsequent compression back into a liquid. After passing via a heat exchanger, the heated refrigerant is transferred to a different body of water for use in the central heating system. The cycle then repeats as the liquid refrigerant passes through an expansion valve in the last stage, which lowers the pressure and temperature.
Can I use it in my property?Â
A well-insulated housing with high standards of airtightness is essential since heat pumps are most effective in homes that warm up quickly, retain the heat, and need little energy to maintain a temperature after it has been reached. Thus, you must ensure that your property is energy efficient before installing a heat pump if it isn’t already.
When there is little temperature differential between the pump unit and the heat distribution system, heat pumps function most effectively. Because they generate heat at a lower temperature than a traditional central heating system, bigger radiators are needed to distribute the heat over a larger area. As a result, some of your current radiators may need to be replaced.
Although huge, heat-pump-specific radiators can also be used, underfloor heating is optimal. Heat pumps require different controls than conventional central heating systems because they operate more effectively when temperature demands are gradual rather than abrupt.
Properties that are off the gas grid and rely on pricey fuels like electricity, oil, LPG, or coal for space heating are the ones where heat pumps make the most economic sense. Make sure your property is well insulated if you are connected to mains gas, which is less expensive per provided unit than electricity. This is because the heat pump will need to operate effectively to save you money.
A heat pump that operates effectively is likely to be the least carbon-intensive method of heating your home because the majority of the electricity produced in the UK now comes from low-carbon sources.
Furthermore, keep in mind that even though the heat pump doesn’t require much room, it needs to be installed outside where there is good airflow.
How to Choose a Heat Pump
Every domestic heat pump sold in the UK has an EnergyGuide label that compares its heating and cooling performance rating to that of other brands and models on the market.
The heating season performance factor (HSPF), which is a measurement over an average heating season of the total heat provided to the conditioned space, expressed in Btu, divided by the total electrical energy consumed by the heat pump system, expressed in watt-hours, indicates the heating efficiency for air-source electric heat pumps.
What will it cost me?
The price to install an air source heat pumpunit ranges from £6,500 to £15,000. This depends on the size of the building it will heat. Further work may be needed in addition to this to enhance the heat distribution system, such as installing larger radiators to assist with heat distribution. Note that good insulation and fabric installation are prerequisites for an efficient heat pump.
The cost of operation will differ based on the size and insulation level of your home, the type of distribution system you have, the desired room temperature, and the system’s CoP.
How much you save on your annual gasoline expense will depend on the type of fuel you are now using. Potential annual savings, based on a detached home with four bedrooms, are (according to data from the Energy Saving Trust):
The government’s Boiler Upgrade SchemeÂmay provide funding for the installation of air source heat pumps. This saves you £5,000 off the price and installation, subject to availability.
The Boiler Upgrade Scheme is also applicable to ground source heat pumps and biomass boilers in remote areas without access to the gas grid.
Air source heat pumpsrequire little maintenance but do require an annual service. They are dependable, run automatically, and will often last for 20 years or longer.