Vehicle air conditioning apparatus

A vehicle air conditioning apparatus includes a heater core (21) radiating heat of engine coolant to an air stream to be blown off to a vehicle compartment, a sub condenser (4) operative to radiate heat of compressed refrigerant to the air stream to be blown off to the vehicle compartment for condensing refrigerant, an evaporator (7) operative to allow expanded refrigerant by an expansion valve (6) to absorb heat of the air stream in the vehicle compartment to be evaporated, a variable displacement compressor (2) operative to compress evaporated refrigerant to be discharged to the condenser (4), a sensor (9) that detects a discharge refrigerant pressure of the compressor (2), and a compressor control means (100) operative to control a discharge refrigerant volume of the compressor (2) so as to compel a blow-off temperature to lie at a given temperature in response to a detected result of the sensor (9).