Heat exchange device for transferring heat from fluids in the gaseous state to fluids in the liquid and/or vapor state and comprising at least one heat-exchange module including a plurality of superimposed plates, each formed by two sheets (31,32) joined at points of junction and deformed to obtain channels adapted to accommodate a heat transfer fluid and paths for the passage of the fumes, externally to the plates, in thermal contact with each other, such module having at least one inlet duct and an outlet duct for the heat transfer fluid, a box-shaped body in which such module is inserted having at least one inlet opening (6,6',8') and at least one outlet opening (7, 7'), wherein • the plates are side by side according to a staggered design and are assembled in the plurality parallel to each other but asymmetrically, so that each of them is rotated by 180° with respect to the axis perpendicular to the plane of parallelism between the plates themselves, with respect to the contiguous plate, the side by side arrangement of two adjacent plates being such as to make the bulging parts of the channels of a plate correspond with the recessed parts of the adjacent plates at the junction points, so that the space between two plates, which constitutes the fume path, is an undulated path, • each plate comprises at least one inlet tube for the fluid and at least one extraction tube for the fluid itself positioned in proximity to opposite corners of the plate, characterized in that the at least one inlet opening (6, 6', 8') is located on one of the four faces perpendicular to the plane of parallelism of the plates and the at least one outlet opening (7,7') is located on at least one of the remaining faces, both the inlet opening (6, 6', 8') and the outlet opening (7,7') being selectively operable, • the connection of the tubes (35,36) for connecting the plates to the inlet and outlet ducts (4,5) of the exchanger in its entirety is obtained by means of a substantially omega-shaped bracket, with the two arms (91,92) constrained to the box-shaped body, while the tubes (35 or 36) are inserted in openings obtained in the central part of the bracket itself. • the plates are side by side according to a staggered design and are assembled in the plurality parallel to each other but asymmetrically, so that each of them is rotated by 180° with respect to the axis perpendicular to the plane of parallelism between the plates themselves, with respect to the contiguous plate, the side by side arrangement of two adjacent plates being such as to make the bulging parts of the channels of a plate correspond with the recessed parts of the adjacent plates at the junction points, so that the space between two plates, which constitutes the fume path, is an undulated path, • each plate comprises at least one inlet tube for the fluid and at least one extraction tube for the fluid itself positioned in proximity to opposite corners of the plate, • the connection of the tubes (35,36) for connecting the plates to the inlet and outlet ducts (4,5) of the exchanger in its entirety is obtained by means of a substantially omega-shaped bracket, with the two arms (91,92) constrained to the box-shaped body, while the tubes (35 or 36) are inserted in openings obtained in the central part of the bracket itself.