Heat-pump installation which is configured for simultaneous heating and cooling, having a heat source and having a heat sink and also having - a first heat pump, which is in the form of a liquid-liquid heat pump and is connected on a source side to the heat source and on a sink side to the heat sink, wherein - the heat source comprises a cooling circuit having a cooling feed, a cooling return, a cooling buffer store for cold water, and, in the connected state, a cooling consumer, - the heat sink comprises a heating circuit having a heating feed, a heating return, a heating buffer store for heating water, and a heating consumer, wherein the heating circuit has, as an alternative or in addition to the heating buffer store and the heating consumer, a hot-water store, - wherein, via the first heat pump, a heat displacement between the cooling circuit and the heating circuit is realized during operation such that there is simultaneously provided a cooling power on the side of the cooling circuit and a heating power on the side of the heating circuit, - there is arranged an auxiliary unit which is connected, in particular hydraulically, to the cooling circuit and to the heating circuit, wherein the auxiliary unit is configured both for providing additional heat for the heating circuit and for providing additional cold for the cooling circuit, - having a control unit for controlling the operation of the heat-pump installation, wherein the auxiliary unit is a second heat pump which is in the form of an air-liquid heat pump and which is reversibly operable, so that it can feed heat into the heating circuit in a heating mode and can feed cold into the cooling circuit in a cooling mode. - a first heat pump, which is in the form of a liquid-liquid heat pump and is connected on a source side to the heat source and on a sink side to the heat sink, wherein - the heat source comprises a cooling circuit having a cooling feed, a cooling return, a cooling buffer store for cold water, and, in the connected state, a cooling consumer, - the heat sink comprises a heating circuit having a heating feed, a heating return, a heating buffer store for heating water, and a heating consumer, wherein the heating circuit has, as an alternative or in addition to the heating buffer store and the heating consumer, a hot-water store, - wherein, via the first heat pump, a heat displacement between the cooling circuit and the heating circuit is realized during operation such that there is simultaneously provided a cooling power on the side of the cooling circuit and a heating power on the side of the heating circuit, - there is arranged an auxiliary unit which is connected, in particular hydraulically, to the cooling circuit and to the heating circuit, wherein the auxiliary unit is configured both for providing additional heat for the heating circuit and for providing additional cold for the cooling circuit, - having a control unit for controlling the operation of the heat-pump installation, wherein the auxiliary unit is a second heat pump which is in the form of an air-liquid heat pump and which is reversibly operable, so that it can feed heat into the heating circuit in a heating mode and can feed cold into the cooling circuit in a cooling mode.