Heat exchange unit

A heat exchange unit, comprising a plurality of heat transfer members, which are formed of a metallic thin sheet into a predetermined shape and combined in parallel and integrally with each other, each of said heat transfer members being provided on at least a part thereof with a heat transfer face having opposite surfaces with which first and second heat exchange fluids are to come into contact, respectively, first gap portions through which said first heat exchange fluid is to pass and second gap portions through which said second heat exchange fluid is to pass being provided alternately between adjacent two heat transfer faces, and a first opening communicating with said first gap portions to cause the first heat exchange fluid to flow into and out from said first gap portions and a second opening communicating with said second gap portions to cause the second heat exchange fluid to flow into and out from said second gap portions being provided separately from each other,

• wherein:
• each of said heat transfer members is formed into a rectangular shape, which has on respective sides thereof flat portions having a prescribed width;
• of said plurality of heat transfer members, adjacent two heat transfer members between which said first gap portion is located are water-tightly welded together at the flat portions thereof on a side where said second opening is placed, and adjacent two heat transfer members between which said second gap portion is located are water-tightly welded together at the flat portions thereof on a side where said first opening is placed, and the adjacent two heat transfer members are closed on the side where said first opening is placed;
• and
• the plurality of heat transfer members as combined are inserted, at the side where said first opening is placed, into a fitting hole of an end plate, said fitting hole having a shape substantially coinciding with an end shape of said plurality of heat transfer members as combined on the side where said first opening is placed, and said plurality of heat transfer members are welded to said end plate along said fitting hole.