Heat exchanger

A brazed plate heat exchanger for exchanging heat between at least two fluids, the heat exchanger comprising:

• (a) several heat exchanger plates, wherein each of the several heat exchanger plates has sealing surfaces and a pressed pattern comprising depressions and elevations adapted to keep the plates on a distance from one another by contact points between the elevations and the depressions of neighboring heat exchanger plates of the several heat exchanger plates under formation of interplate flow channels for media to exchange heat;
• (b) at least four port openings being arranged through each of the several heat exchanger plates and being placed in corner regions of the several heat exchanger plates and having selective fluid communication with the interplate flow channels such that the fluids to exchange heat will flow between the port openings of the several heat exchanger plates;
• and
• (c) a circumferential seal sealing off the interplate flow channels from communication with surroundings,
• wherein the several heat exchanger plates are joined by brazing,
• wherein the circumferential seal results partly from contact between skirts of the neighboring heat exchanger plates of the several heat exchanger plates contacting one another and forming skirt brazed areas, said skirts extending at least partly along only two opposite sides of each of the several heat exchanger plates, and partly from contact between flat brazed areas in the sealing surfaces of the neighboring heat exchanger plates of the several heat exchanger plates contacting one another and extending along two other opposite sides of each of the several heat exchanger plate,
• wherein each port opening of the several heat exchanger plates is surrounded by a first flat brazing surface on a first side and a second flat brazing surface on a second side, and
• wherein the first flat brazing surface and the second flat brazing surface of at least two of the port openings of each of the several heat exchanger plates are provided on a level different from a level of the first flat brazing surface and the second flat brazing surface of at least two other of the port openings of each of the several heat exchanger plates, and thereby providing selective fluid flow between the port openings and the interplate flow channels.