Plastic heat exchanger and method of manufacturing the same

A method of fabricating a plastic heat exchanger having an integral structure of a plastic heat exchanger tube, a header and a header cap, comprising:

• preparing the header to comprise a junction having a fusion bead and a melted material inflow groove formed along an outer circumferential surface of the fusion bead by injection molding, wherein the fusion bead projects above a surface of the header, and wherein the melted material inflow groove is recessed below the surface of the header;
• preparing the header cap to comprise a refrigerant inlet tube and a refrigerant outlet tube by insert injection molding;
• coupling the plastic heat exchanger tube and the junction of the header by using a heat fusing jig to provide an integral structure of the plastic heat exchanger tube and the junction of the header, wherein the coupling causes inflow of melted materials into the melted material inflow groove of the junction, wherein the melted materials are melted material from the fusion bead and melted material from the plastic heat exchanger tube;
• and
• fusing the header cap onto the header to provide an integral structure of the header cap and the header.