A plate heat exchanger (100) including a number of heat exchanger plates (1), which are arranged beside each other and connected to each other by means of a braze connection to form a stack of plates (2), wherein the heat exchanger plates are substantially manufactured in stainless steel containing chromium, wherein the plate heat exchanger (100) includes a number of port channels extending through at least some of the heat exchanger plates (1), and wherein the plate heat exchanger (100) further including end plates (3, 5) covering each end of the stack of plates (2) and having port holes associated with the port channels, where at least one end plate (3, 5) has at least one port hole provided with a cover (9, 12) and where said cover includes means (9, 12) for increasing the strength and means (14, 15) for sealing off the at least one end plate (3, 5) against an adjacently arranged heat exchanger plate.