Vehicle air conditioning device

A vehicle air-conditioning device comprising:

• a refrigerant circuit including a compressor, an indoor heat exchange unit, and an external heat exchange unit;
• an air-conditioning unit in which the indoor heat exchange unit is disposed;
• and
• a control device that controls the refrigerant circuit and the air-conditioning unit,
• wherein the refrigerant circuit has a hot gas bypass that decompresses at least part of refrigerant compressed by the compressor without the refrigerant passing through the indoor heat exchange unit and the external heat exchange unit, and returns the decompressed refrigerant to the compressor, and
• the control device
• is capable of executing a hot gas heating operation of heating an inside of a cabin by causing part of the refrigerant compressed by the compressor to dissipate heat in the indoor heat exchange unit without causing the refrigerant to absorb heat in the external heat exchange unit, and
• adjusts a heating capacity by opening and closing at least one of a decompression unit provided between the indoor heat exchange unit and the compressor or a hot gas decompression unit provided in the hot gas bypass during the hot gas heating operation.