Method of and arrangement for separating fluid streams in a heating device

Device for separating fluid flows (L1, L2, L1', L2') in a heater arrangement (1), especially for heating the interior of a motor vehicle, whereby the heating arrangement has at least a heater (4) with a multiplicity of lamellar type heat output elements. An essentially planar separating body (5) has a through hole for sliding the separating body on to the heating body.