Air conditioning apparatus for vehicle

An air conditioning apparatus for a vehicle, comprising:

• a coolant cycle including a compressor for compressing a coolant, an outdoor-side coolant heat exchanger for exchanging heat of the coolant compressed by the compressor with ambient air, an expansion unit for expanding the coolant after heat exchange at the outdoor-side coolant heat exchanger, an indoor-side coolant heat exchanger for exchanging heat of the coolant expanded by the expansion unit with air conditioning wind supplied into a vehicle cabin, and a piping connecting the compressor, the coolant heat exchangers and the expansion unit in communication with each other;
• a water-coolant heat exchanger arranged between the compressor and the outdoor-side coolant heat exchanger to exchange heat of the coolant discharged from the compressor with cooling water of a power source for driving the vehicle;
• a flow-path switching unit for selectively introducing the coolant discharged from the compressor to either a flow path for the water-coolant heat exchanger or another flow path to avoid the water-coolant heat exchanger;
• a detection unit for detecting a temperature of the cooling water flowing into the power source;
• and
• a control unit for controlling the flow-path switching unit in a manner that the coolant discharged from the compressor is introduced to the water-coolant heat exchanger when the temperature of the cooling water is equal to or less than a predetermined temperature and that the coolant discharged from the compressor avoids the water-coolant heat exchanger when the temperature of the cooling water is more than the predetermined temperature.