Abstract: Addressed is a heat exchanger including a housing having an internal wall defining at least one internal chamber incorporating at least one core having a wall defining in the chamber, with the internal wall of the housing across from it, at least one exchange cavity including at least one tubular hollow coil having ends passing through the housing to make it possible for it to be supplied with a primary fluid, at least one inlet and at least one outlet that are axially opposite for circulation of a secondary liquid in the exchange cavity in contact with each coil and at least one tangential spreader rib, extending in projection with respect to a wall across from the coil and not parallel to the axial circulation direction, but adapted in order not to inhibit the circulation of the secondary liquid. The thermal exchanger includes at least one tangential helical rib and at least one coil having different winding directions.