Abstract: The invention concerns a dual pump, comprising an electric motor (18) including a drive shaft, the shaft including, at each of its axial ends, a shaft output (21, 22), and two pump impellers, each shaft output driving a respective pump impeller, one first of the pump impellers (23) operating at low pressure and high flow rate, and the second of the pump impellers (30) operating at higher pressure and lower flow rate. The water pumped by the second pump impeller (30) is drawn proximate the outlet of the first pump impeller (23) and returns to the inlet of the second pump impeller. The drawing point is situated in a low pressure pump chamber, upstream of the low pressure outlet (16). The invention is applicable to swimming pool maintenance.

Abstract: The invention relates to a heat pump. It relates to a heat pump which, in a primary circuit, comprises a compressor (10), a condenser (12) forming a heat exchanger between the refrigerating fluid and the swimming pool water, an expander (14) and an evaporator (16) forming a heat exchanger between the external surroundings and the refrigerating fluid. The condenser (12) comprises two heat exchange circuits and the heat pump comprises a pressure sensor (18), a member for switching the circulation of the refrigerating fluid between states in which it is circulated in just one or in at least two of the heat exchange circuits, and a member for controlling the switching member according to the value of the signal from the sensor (18). Application to the heating of swimming pool water.