F28D 7/1638

Heat-exchange apparatus having stationary tubular conduit assemblies for both heat-exchange media, the media being in contact with different sides of a conduit wall the conduits being arranged in parallel spaced relation {with conduit assemblies having a particular shape, e.g. square or annular; with assemblies of conduits having different geometrical features; with multiple groups of conduits connected in series or parallel and arranged inside common casing with particular pattern of flow or the heat exchange medium flowing inside the conduits assemblies, e.g. change of flow direction from one conduit assembly to another one }