An air conditioner for a vehicle, comprising:
- a refrigeration cycle including:
- a compressor configured to compress and discharge a refrigerant,
- a heating unit including a heating heat exchanger configured to condense the refrigerant discharged from the compressor during a heating operation of heating a space to be air conditioned, the heating unit being configured to heat ventilation air to be blown to the space to be air conditioned using the refrigerant as a heat source,
- an outside-air heat exchange unit including an outside air heat exchanger in which the refrigerant absorbs heat from outside air during the heating operation,
- a first expansion valve disposed between an outflow port of the heating heat exchanger and an inflow port of the outside air heat exchanger, the first expansion valve being configured to decompress the refrigerant flowing out of the heating heat exchanger,
- a second expansion valve configured to decompress the refrigerant flowing out of at least one of the heating heat exchanger or the outside air heat exchanger, and
- an evaporator configured to cause the refrigerant decompressed by the second expansion valve to absorb heat and evaporate;
- and
- a controller configured to perform a condensation heat defrosting operation in which frost adhering to the outside air heat exchanger is melted and defrosted using heat of the refrigerant absorbed in the evaporator, and a heating operation in which a heating of the space to be air conditioned is performed using heat dissipation from the refrigerant in the heating heat exchanger, wherein
- the controller includes a compression control unit and a decompression control unit, and
- when the condensation heat defrosting operation and the heating operation of the space to be air conditioned are performed in parallel, and when a heating operation temperature or pressure of the refrigerant in the heating heat exchanger for the heating operation is different from a defrosting operation temperature or pressure of the refrigerant in the outside air heat exchanger for the condensation heat defrosting operation,
- the compression control unit is configured to achieve any one of the heating operation temperature or pressure of the refrigerant in the heating heat exchanger, or the defrosting operation temperature or pressure of the refrigerant in the outside air heat exchanger by controlling operation of the compressor, and
- the decompression control unit is configured to achieve the other one of the heating operation temperature or pressure of the refrigerant in the heating heat exchanger, or the defrosting operation temperature or pressure of the refrigerant in the outside air heat exchanger by controlling operation of the first expansion valve.