The HPWSBE water heater consists of a stainless steel hot water cylinder and an integrated air-to-water heat pump. Domestic hot water is produced by the air-to-water heat pump from the ambient air (provided the ambient air meets the required criteria), possibly using 160 mm or 190 mm diameter air ducts.

As an option, an additional external heat source (e.g. a boiler or solar thermal panels) can be connected to the hot water cylinder's heat exchanger. The HPWSBE water heater is equipped with the PV Ready function, which heats the contents of the boiler to a higher temperature as soon as the photovoltaic panel inverter triggers a contact.