Abstract: A heat pump includes a compressor for compressing a refrigerant, a first heat exchanger, a main expansion mechanism and a second heat exchanger arranged in a refrigeration path, the compressor having a suction port, a compression port and an injection port; a gas injection valve connected on a first side to the refrigeration path between the first heat exchanger and the main expansion mechanism and on a second side to the injection port of the compressor; a liquid injection valve connected on a first side to the refrigeration path between the first heat exchanger and the main expansion mechanism and on a second side between the second heat exchanger and the suction port of the compressor; and a controller, the controller being configured to operate the gas injection valve to inject at least partly gaseous refrigerant into the compressor through the injection port of the compressor, and to operate the liquid injection valve to inject substantially liquid refrigerant into the compressor through the suction port

Abstract: A heat source unit for a heat pump having a refrigerant circuit, the heat source unit having: an outer casing including a bottom plate; and a compressor assembly accommodated in the outer casing, the compressor assembly including a compressor of the refrigerant circuit of the heat pump including a compressor housing, a support plate supporting the compressor, the support plate being mounted via dampers to the bottom plate, and a compressor casing enclosing the compressor and the compressor housing. A damping mechanism is arranged between the compressor and the support plate, and the compressor casing is fixed to the support plate out of contact with the compressor housing.

Abstract: An outdoor unit for a heat pump includes a refrigerant circuit, the outdoor unit including a compressor, a discharge pipe of the refrigerant circuit connected to a discharge side of the compressor, a bottom plate, the bottom plate having a base and an outer flange protruding upward from an outer edge of the base, a heat source heat exchanger supported on the bottom plate, a liquid refrigerant pipe of the refrigerant circuit connected to the heat source heat exchanger, and a defrosting bypass pipe connected at one end to the discharge pipe and at the opposite end to the liquid refrigerant pipe, the defrosting bypass pipe being arranged between an inner side of the flange and an outer side of the heat source heat exchanger.