| 摘要 |
Provided is a vehicle air-conditioning device with which frost formed on an external heat exchanger can be reliably removed, without increasing the number of components and occupancy space. During a heating operation, in cases when it is determined that environmental conditions are present in which frost formation on an external heat exchanger (22) will occur, a coolant passage of a first control valve (24) is set to a maximum opening amount at an expansion means side, and a hot-gas frost-removal operation is performed in which a first solenoid valve (26a) is closed after the coolant passage of the first control valve (24) is set to the maximum opening amount at the expansion means side. As a result, the inside of the external heat exchanger (22) enters a high-temperature high-pressure state and the heat release amount in the external heat exchanger (22) can be increased, thereby enabling the reliable removal of frost formed on the external heat exchanger (22). |
