Air source heat pumps can be used for air cooling, however it is only air-to-air pumps that are capable of this and are usually only seen in commercial buildings, due to the complex nature of having to retrofit ducting to each room of your house. Air-to-water heat pumps are connected up to a wet heating circuit and because of this, cooling by sending cold water through radiators or underfloor heating just doesn’t work like it does with air-to-air systems.