Abstract: Heat pump assembly for seasonal balancing of temperatures in buildings, includes a heat pump (1) having a cold side and a warm side, respectively. The heat exchangers (2, 3) are connected to the cold and the warm side, respectively, in that one of the heat exchangers (3) is connected to a heating/cooling element (4), in that the other heat exchanger (2) is connected to a heat/cold buffer (6), in that the heat pump (1) is of the type liquid-liquid, and in that a valve assembly (7) is arranged in the heat pump (1) to optionally connect the warm or cold side of the heat pump (1) to the heating/cooling element (4), whereby the heating/cooling element (4) optionally may heat or cool.