Heat exchanger

A heat exchanger comprising:

• a plurality of plate pairs arranged in a block, wherein each plate pair comprises a first flow path, a second flow path, a third flow path, and a fourth flow path, wherein each flow path is isolated from one another along an entire space bounded by the plate pair,
• wherein each plate pair comprises a first plate and a second plate,
• wherein the first flow path and the second flow path are each formed between the first and the second plate, wherein the first plate and the second plate bound the first flow path and the second flow path, wherein the third flow path is formed
• (a) between an attachment plate connected to an edge region of the first plate and the first plate, wherein the attachment plate and the first plate bound the third flow path, wherein the attachment plate is not connected to the second plate, or
• (b) between an attachment plate connected to an edge region of the second plate and the second plate, wherein the attachment plate and the second plate bound the third flow path, wherein the attachment plate is not connected to the first plate,
• wherein the attachment plate does not bound the first flow path or the second flow path,
• wherein the fourth flow path is formed between two adjacent plate pairs, and
• wherein the first plate and the second plate of each plate pair have a first end region comprising first, second, and third port regions that are isolated from each other and a second end region comprising fourth, fifth, and sixth port regions that are isolated from each other,
• wherein the first flow path extends between the first port region and the fourth port region, wherein the second flow path extends between the second port region and the fifth port region, and wherein the third flow path extends between the third port region and the sixth port region,
• wherein
• the attachment plate is produced in a single piece planar construction together with the first plate and is connected to an edge region of the first plate, wherein in an assembled state the attachment plate is bent approximately 180 degrees along a vertical axis connecting the attachment plate and the first plate such that the attachment plate abuts the first plate, or
• the attachment plate is produced in a single piece planar construction together with the second plate and is connected to an edge region of the second plate, wherein in an assembled state the attachment plate is bent approximately 180 degrees along a vertical axis connecting the attachment plate and the second plate such that the attachment plate abuts the second plate.