PURPOSE: To improve the dimensional accuracy of a distance between a suction port and a delivery port, fixed to the delivery side and the suction side of an expansion valve, by a method wherein the positioning direction of suction port and delivery port of the expansion valve is made different from the laminating direction of the main body of a heat exchanger.

CONSTITUTION: An expansion valve mounting unit 8 is constituted of an expansion valve mounting plate 81, having a delivery port 81a communicating with the suction side of an expansion valve and a suction port 81b communicating the delivery side of the same valve, and four sheets of plates 91-94, forming refrigerant outlet and inlet port passages 82, 83 communicating the mounting plate 81. The expansion valve mounting plate 81 is not constituted so that the position thereof is arrayed to the suction port 81b and the delivery plate 81a along the laminating direction of the main body 7 of a heat exchanger but vertical to the laminating direction thereof and the plate 81 is attached above the first plate 91. According to this method, a distance between the suction port 81b and the delivery port 81a will never be fluctuated due to the contraction of the main body 7 of the heat exchanger after brazing whereby the dimensional accuracy of the heat exchanger can be improved.