Air-to-water heat pump takes heat from the outdoor air and transfers it to the water which is then used for heating of a house or domestic hot water. Modern heat pump can take heat from air even at low ambient temperatures, so it can work almost all year-round.
S-THERM heat pump is designed for providing hot water for heating in the winter but it can also provide cold water for cooling in summer. If you use fan-coil units, this heat pump can be used for cooling and heating. There is no need for independent air-conditioning unit.