A heat pump system for a vehicle, which makes refrigerant bypass an external heat exchanger and turns off a fan mounted on the external heat exchanger when temperature of the outdoor air is lower than setting temperature and the vehicle enters into an idle state in a heat pump mode, thereby continuously operating the heat pump mode even in the below zero temperature so as to keep heating performance, reducing consumption of electrical power without needing to operate an electric heater, and preventing excessive noise of a fan when the vehicle enters into an idle state in the below zero temperature.

A thermal management system for a vehicle includes a base circuit in which a compressor, a condenser, an expansion valve, and an evaporator are provided in order and in which a refrigerant is circulated, a recirculation circuit branched from a discharge portion of the compressor in the base circuit and joined to an inlet portion of the compressor so that the refrigerant discharged from the compressor is recirculated to an inlet of the compressor, and an adjusting valve positioned at the discharge portion where the recirculation circuit is branched from the base circuit or positioned at the inlet portion where the recirculation circuit is joined to the base circuit, the adjusting valve configured to adjust a flow rate of the refrigerant that flows to the recirculation circuit.

A method for controlling a valve arrangement (12), e.g. in the form of a three way valve, in a vapour compression system (1) is disclosed, the vapour compression system (1) comprising an ejector (6). The valve arrangement (12) is arranged to supply refrigerant to a compressor unit (2) from the gaseous outlet (11) of a receiver (7) and/or from the outlet of an evaporator (9). The vapour compression system (1) may be operated in a first mode of operation (summer mode) or in a second mode of operation (winter mode). When operated in the second mode of operation, it is determined whether or not conditions for operating the vapour compression system (1) in the first mode of operation are prevailing. If this is the case, the valve arrangement (12) is actively switched to the first mode of operation by closing a first inlet (13) towards the evaporator (7) and fully opening a second inlet (14) towards the receiver (7).

A method for controlling a valve arrangement (12), e.g. in the form of a three way valve, in a vapour compression system (1) is disclosed, the vapour compression system (1) comprising an ejector (6). The valve arrangement (12) is arranged to supply refrigerant to a compressor unit (2) from the gaseous outlet (11) of a receiver (7) and/or from the outlet of an evaporator (9). The vapour compression system (1) may be operated in a first mode of operation (summer mode) or in a second mode of operation (winter mode). When operated in the second mode of operation, it is determined whether or not conditions for operating the vapour compression system (1) in the first mode of operation are prevailing. If this is the case, the valve arrangement (12) is actively switched to the first mode of operation by closing a first inlet (13) towards the evaporator (7) and fully opening a second inlet (14) towards the receiver (7).

Disclosed therein are a heat pump system for a vehicle and a method of controlling the heat pump system, which determines that frosting begins on an exterior heat exchanger and carries out a defrosting control if a difference value between outdoor temperature and refrigerant temperature of an outlet side of the exterior heat exchanger is above a frosting decision temperature in a heat pump mode, thereby increasing frost-prevention and defrosting effects and enhancing heating performance and stability of the system because the system recognizes the beginning of frosting on the exterior heat exchanger at a proper time so as to carry out the defrosting control.

The invention relates to a refrigerant circuit (10) of a vehicle air-conditioning system (12), in particular for electric vehicles, comprising a compressor unit (14) which includes a first compressor (16) and a second compressor (18) arranged downstream for compressing a refrigerant (20), a condenser (22) for heating air (24) which can be supplied to a vehicle interior, a first pressure reducing unit (26) arranged downstream of the condenser (22) for decompressing the refrigerant (20) from the condenser (22), a heat exchanger (28) through which refrigerant flows for heat exchange with vehicle ambient air (30), an evaporator (32) for cooling air (24) which can be supplied to a vehicle interior, and a second pressure reducing unit (34) arranged upstream of the evaporator (32) for decompressing the refrigerant (20) from the heat exchanger (28), the second compressor (18), the condenser (22) and the first pressure reducing unit (26) being bypassed in a cooling mode of the vehicle air-conditioning system (12), and the evaporator (32) and the second pressure reducing unit (34) being bypassed in a heating mode of the vehicle air-conditioning system (12). The invention furthermore relates to a method of air-conditioning a vehicle interior, in particular by means of the refrigerant circuit (10) described above.

A method of operating a cooling apparatus is described that allows flexible cooling lines connecting an inlet manifold to an outlet manifold to be safely added or removed during operation of the cooling apparatus without causing unstable two-phase flow. The method can include providing a cooling apparatus having an inlet manifold, an outlet manifold, and a bypass extending from the inlet manifold to the outlet manifold. Each manifold can include a plurality of connection ports, such as quick-connect couplers, to accommodate adding and removing cooling lines between the inlet manifold and the outlet manifold. The method can include providing a flow rate of single-phase liquid coolant to the inlet manifold and setting a pressure regulator in the bypass to provide a certain flow rate through the bypass. The flow rate through the bypass can be determined as a function of an average flow rate through each of the cooling lines.

A method of operating a cooling apparatus is described that allows flexible cooling lines connecting an inlet manifold to an outlet manifold to be safely added or removed during operation of the cooling apparatus without causing unstable two-phase flow. The method can include providing a cooling apparatus having an inlet manifold, an outlet manifold, and a bypass extending from the inlet manifold to the outlet manifold. Each manifold can include a plurality of connection ports, such as quick-connect couplers, to accommodate adding and removing cooling lines between the inlet manifold and the outlet manifold. The method can include providing a flow rate of single-phase liquid coolant to the inlet manifold and setting a pressure regulator in the bypass to provide a certain flow rate through the bypass. The flow rate through the bypass can be determined as a function of an average flow rate through each of the cooling lines.

In a refrigeration cycle system, switching is allowed between a parallel operation mode and a series operation mode. In the parallel operation mode, a refrigerant, upon leaving a load side heat exchanger, parallelly flows through a high-pressure side passage of each of a first internal heat exchanger and a second internal heat exchanger and then flows into an expansion valve. In the series operation mode, the refrigerant, upon leaving the load side heat exchanger, flows through the high-pressure side passage of the first internal heat exchanger, further flows through the high-pressure side passage of the second internal heat exchanger, and then flows through a high-pressure side bypass pipe into the expansion valve.

A laminated header includes: a plurality of plate-like members laminated with each other; one first opening; a plurality of second openings; and a distribution flow passage connecting the one first opening and each of the plurality of second openings to each other. The distribution flow passage includes: a first passage having a straight line shape; a first branching flow passage for the first passage to branch into a plurality of passages; a second passage that has a straight line shape and is connected to each of the plurality of passages branched in the first branching flow passage; a second branching flow passage for the second passage to branch into a plurality of passages; and a third passage that has a straight line shape and is connected to each of the plurality of passages branched in the second branching flow passage.