Air Source Heat Pumps (ASHPs) are becoming an increasingly popular option for homeowners in the UK who are looking for a sustainable and cost-effective way to heat their homes.  Unlike traditional fossil fuel-based heating systems, ASHPs use heat from the air outside to heat the home or building, making them a great investment as a renewable energy source.  Another benefit of ASHPs is their high efficiency, measured by the Coefficient of Performance (COP), which is the ratio of heat output to energy input.  Modern ASHPs have a COP of 4, meaning that for every unit of electricity used, the system produces 4 units of heat, making them significantly more efficient than traditional heating systems which can have a COP as low as 0.8.  In addition to the environmental and efficiency benefits, ASHPs can also save homeowners money on their energy bills in the long run. While the initial installation costs can be high, the long-term savings on energy costs and less frequent maintenance make this more cost efficient than traditional heating systems. When considering investing in an Air Source Heat Pump, it is important to consult a professional to determine if the system is a good fit for your home or building. Factors to consider include:  Make sure that the installer is also properly qualified and that the system is installed to the highest standards.  There are three main types of Air Source Heat Pumps:  The monobloc system has all the components housed in one unit, usually installed outside of the home. Its benefits include: The split system has an outdoor unit that houses the compressor and heat exchanger, and an indoor unit that circulates the heat around the home. The outdoor unit is connected to the indoor unit through pipes and electrical cables.  Benefits of this system include:  Finally, the hybrid system combines a conventional boiler system with an air source heat pump. The benefits of this system include: by David Johnson, Technical and Category Manager at The Underfloor Heating Store Building, Design & Construction Magazine | The Choice of Industry Professionals