Patent ID: 7451807

Claim:
A heat exchanger comprising: plates, with a pattern of grooves and with inlet and outlet connections, placed in a package and brazed together to form separate ducts for two media, a first set of ducts being provided for allowing a first medium to flow between a first pair of the plates, and a second set of ducts being provided for allowing a second medium to flow between alternate pairs of the plates; and at least one delimited zone defined by a barrier within the package, the barrier blocking off areas inside the second set of ducts for the second medium, while not blocking off areas inside the first set of ducts for the first medium, the delimited zone having an inlet, in a form of a cross-over passage arranged between the first set of ducts and the second set of ducts, and an outlet for circulation of the first medium through the areas within the delimited zone under heat exchange with the first medium.