Patent ID: 7234516

Claim:
An air conditioner for vehicle use comprising: a blower ( 21 ) for blowing air into a vehicle compartment; a cooler ( 2 ) for cooling the air which has been blown by the blower ( 21 ); a heater ( 3 ) for heating the air which has been blown by the blower ( 21 ); an air conditioning casing ( 4 ) for accommodating the cooler ( 2 ) and heater ( 3 ), having a heater bypass passage ( 5 ) to make a detour of the heater ( 3 ) so as to let the air flow to the downstream side; a cold wind side air mixing door ( 6 ) for controlling a state of communication of the heater bypass passage ( 5 ), the cold wind side air mixing door ( 6 ) being provided in the air conditioning casing ( 4 ); and a hot wind side air mixing door ( 7 ) for controlling a quantity of the wind passing through the heater ( 3 ), the hot wind side air mixing door ( 7 ) being provided in the air conditioning casing ( 4 ), wherein the cooler ( 2 ) is arranged on the upstream side of the air flow of the heater ( 3 ) and the entrance portion of the heater bypass passage ( 5 ), the air conditioner for vehicle use further comprising: a communicating port ( 15 ) for communicating the inside with the outside of the air conditioning casing ( 4 ), the communicating port ( 15 ) being arranged in the air conditioning casing ( 4 ) on the upstream side of the air flow of the heater ( 3 ) and the entrance portion of the heater bypass passage ( 5 ); and an air blowing control means (S 3 , S 4 , S 13 , S 14 , S 23 , S 24 , S 33 , S 34 ) for conducting an air blowing mode in which the blower ( 21 ) is operated under the condition that both the air mixing doors ( 6 , 7 ) are closed.