A heat pump system in a vehicle connected with a refrigerant line through which refrigerant flows for controlling cooling/heating of a cabin of the vehicle, including a compressor for compressing refrigerant, an outdoor heat exchanger for condensing high temperature and high pressure refrigerant compressed at the compressor, and an expansion valve for expanding the refrigerant compressed thus, comprising:
- an indoor heat exchanger arranged between the compressor and the expansion valve, connected to one another with the refrigerant line;
- and
- a first valve connected to the compressor, the outdoor heat exchanger and the indoor heat exchanger with the refrigerant line for changing a direction of a refrigerant flow to the compressor, the outdoor heat exchanger and the indoor heat exchanger according to cooling, heating, and dehumidifying modes of the vehicle to control the refrigerant flow along the refrigerant line,
- wherein the indoor heat exchanger includes:
- a first header tank connected to the expansion valve with the refrigerant line;
- a second header tank connected to the first valve and a second valve in parallel;
- and
- a heat exchanger portion provided between the first header tank and the second header tank, and having an inside partitioned by a partition wall, provided in a length direction thereof, to form first, and second flow passages,
- wherein the first valve connected to the second flow passage is a 4-way valve,
- wherein the refrigerant line connected between the first valve and the first flow passage has the second valve provided to the refrigerant line, the second valve connected to the first flow passage,
- wherein the second valve is connected to an inlet to the compressor with a connection line,
- wherein the second valve is mounted at a portion of the refrigerant line from which the connection line is branched,
- wherein the second valve is a 3-way valve directly receiving the refrigerant from the first valve, and wherein the 3-way valve is configured for supplying the refrigerant directly-introduced from the first valve and introduced from the first flow passage, to the compressor through the connection line, for supplying the refrigerant directly-introduced from the first valve, to the compressor through the connection line, or for supplying the refrigerant directly-introduced from the first valve, to the compressor through the connection line and to the first flow passage, according to the heating, cooling, or dehumidifying mode of the vehicle,
- wherein, when the vehicle is in the cooling mode, the first valve connects between an outlet of the compressor and the outdoor heat exchanger and connects between the indoor heat exchanger and the inlet to the compressor, and the second valve becomes to be in fluid-communication with the first flow passage,
- wherein, when the vehicle is in the heating mode, the first valve connects between the outlet of the compressor and the indoor heat exchanger, and between the outdoor heat exchanger and the inlet to the compressor, and the second valve cuts off fluid-communication with the first flow passage, or
- wherein, when the vehicle is in the heating and dehumidifying modes, the first valve connects between the outlet of the compressor and the indoor heat exchanger, and between the outdoor heat exchanger and the inlet to the compressor, and the second valve becomes in fluid-communication with the first flow passage.