Double wall plate heat exchanger

A double wall plate heat exchanger comprising:

• a plurality of double wall plate heat exchanger elements, wherein said heat exchanger elements are formed with a pattern of ridges and grooves providing contact points between at least some crossing ridges and grooves of neighboring heat exchanger elements under formation of flow channels between the heat exchanger elements for fluids to exchange heat, said flow channels being in selective fluid communication with each other through port openings of the heat exchanger elements, wherein each of the heat exchanger elements comprises at least two joined plates, wherein said plates are formed with ridges and grooves to form the pattern of ridges and grooves of the heat exchanger elements, and wherein leakage channels are formed between the plates of each heat exchanger element for fluid leaking from a flow channel;
• wherein
• the plates are provided with cooperating elevations and indentations forming the leakage channels extending across the ridges and grooves between the plates of each heat exchanger element;
• at least one connecting space formed between the plates of each heat exchanger element, said at least one connecting space connecting the leakage channels between the plates of each heat exchanger element;
• and
• the at least one connecting space is connected to a leakage outlet.