The heat pumps in the WPL E series are suitable for both new build and renovations. The intermediate vapour injection means a high flow temperature and exemplary heating output are achieved even at low outside temperatures. Even at -20 °C, the WPL still reaches flow temperatures of +60 °C. This ensures efficient heating and DHW operation throughout the year. The lower the required flow temperature, the higher the efficiency of the heat pump. The distance between the fins of the evaporator, the heating of the condensate pan via the refrigerant circuit, and the control of the refrigerant circuit reversal enable optimum defrosting and therefore efficient operation.