VEHICULAR AIR CONDITIONER

To provide a vehicular air conditioner that is configured so that a refrigerant circuit can be maintained in a stable state, in an operation state of air conditioning where a balance of a refrigerant circuit is kept.SOLUTION: A vehicular air conditioner is provided with: a refrigerant circuit; a heat medium circuit that has a high-temperature heat medium passage through which a high-temperature heat medium heated by heat radiation of the refrigerant circuit is flowed and a low-temperature heat medium passage through which a low-temperature heat medium cooled by heat absorption of the refrigerant circuit is flowed; and an air conditioning unit in which air heat medium heat exchangers provided in the heat medium circuit are arranged in an air passage through which air is supplied into a vehicle interior, where the heat medium circuit comprises at least an external heat exchanger that makes the heat medium exchange heat with outside air and further comprises passage switching means for separating the external heat exchanger from the high-temperature heat medium passage and the low-temperature heat medium passage.SELECTED DRAWING: Figure 1 【課題】冷媒回路のバランスが保たれている空調の運転状態において、冷媒回路の安定状態を維持できるようにする。【解決手段】冷媒回路と、前記冷媒回路の放熱で加熱された高温熱媒体を流す高温熱媒体流路と前記冷媒回路の吸熱で冷却された低温熱媒体を流す低温熱媒体流路を有する熱媒体回路と、前記熱媒体回路に設けられる空気熱媒体熱交換器を車室内に供給する空気流路に配置した空調ユニットを備える車両用空調装置であって、前記熱媒体回路は、少なくとも外気と熱媒体が熱交換する外部熱交換器を備えると共に、前記外部熱交換器を前記高温熱媒体流及び前記低温熱媒体流路から切り離すための流路切替手段を備える車両用空調装置を提供する。【選択図】図１