VEHICULAR HEAT PUMP APPARATUS, AND VEHICULAR AIR CONDITIONING APPARATUS

The vehicular heat pump apparatus is provided with: an electric compressor that compresses and discharges an intake refrigerant; a water-refrigerant heat exchanger that can cause heat to be dissipated from a high-temperature, high-pressure refrigerant discharged by the electric compressor to a coolant; a casing that houses the electric compressor and the water-refrigerant heat exchanger; a coolant guiding-in unit that can guide the coolant from outside the casing into the water-refrigerant heat exchanger; a coolant guiding-out unit that can guide the coolant out of the water-refrigerant heat exchanger to the outside of the casing; a single refrigerant guiding-out unit that guides the refrigerant that has passed through the water-refrigerant heat exchanger to the outside of the casing; and a first refrigerant guiding-in unit and a second refrigerant guiding-in unit that guide a low-pressure refrigerant from outside the casing toward the electric compressor.