Patent attributes
A vehicle air conditioner which is capable of inhibiting liquid return to a compressor and generation of noise due to bumping in an accumulator. There are executed a heating mode to close a solenoid valve 17, open a solenoid valve 21, let a refrigerant radiate heat in a radiator 4, decompress the refrigerant through an outdoor expansion valve 6, let the refrigerant absorb heat in an outdoor heat exchanger 7, and send the refrigerant to an accumulator 12, and a dehumidifying and heating mode to open the solenoid valve 17, close the solenoid valve 21, decompress the refrigerant through an indoor expansion valve 8, let the refrigerant absorb heat in a heat absorber, and generate heat in an auxiliary heater 23. A valve position of the outdoor expansion valve 6 is reduced for a predetermined period of time before shifting from the heating mode to the dehumidifying and heating mode.