To reduce the burden on an operator in heat insulating treatment work, and also eliminate drain treatment structure of dewing water by arranging an urethane structure so as to enclose a pipe body in which a fluid to be heated and be cooled flows.

In an air-conditioning system including a heat exchanging part, and an indoor radiating/heat absorbing part, a frame 3 is arranged to fill an urethane structure around a double type heat exchanger 1, and the heat exchanger 1 is positioned on a prescribed position in the frame 3 by a core 4 made of foaming styrene. After that, the around of the heat exchanger 1 is enclosed in a close type by the frame 3, and urethane is filled into the frame 3 so as to form a urethane structure. Since a heat insulating part is constituted by means of filling, heat insulating treatment work of a complicated piping is simplified.