Air conditioning apparatus, heat exchanger for use in the apparatus and apparatus control method

摘要

The present invention provides an air conditioning apparatus for automobiles equipped with a heat exchanger and a control method for the apparatus, by which the heat transfer area of the heat exchanger can be properly controlled to permit a stable cycle operation, even when the capacity of a condenser is relatively overly enhanced under a condition of the low atmospheric temperature. The apparatus and the control method are achieved with such an arrangement that either one or both of headers of a heat exchanger is provided with at least one refrigerant flow rate control valve capable of opening and closing refrigerant passages in each header, the heat exchanger has a refrigerant inlet provided in one header and a refrigerant outlet provided in the other header, and the control valve is opened and closed to change the number of the passages allowing the refrigerant to pass therethrough, for thereby changing the effective heat transfer area for heat exchange dependent on the atmospheric temperature.