AIR CONDITIONER FOR VEHICLE

An air conditioner includes an air conditioning unit installed in a cabin, and a supply unit supplying air conditioned by the air conditioning unit to the cabin. The air conditioning unit includes a refrigeration cycle device having a compressor, a radiator, a decompression device, and an evaporator. One of the radiator and the evaporator functions as a use-side heat exchanger that generates conditioned air by heat exchange between refrigerant and air. The refrigeration cycle device has a high-pressure protection device that discharges the refrigerant to the outside when the pressure of the refrigerant flowing through a passage, which is defined from a refrigerant discharge side of the compressor to a refrigerant inlet side of the decompression device, exceeds a predetermined reference pressure. The high-pressure protection device is configured to discharge the refrigerant to the outside through an outside communication portion communicated with the outside of the cabin.