The heating system (1), especially for a motor vehicle, has at least one heating element, especially a PTC element (2), which is part of a heating train (8) formed by a sub-assembly, whereby several sub-assemblies installed side by side are part of the heating system. A flow resistance element is installed next to one sub-assembly or between two, and is in the form of a grill element (14) fitted in a frame. The flow resistance element may be a plastic or metal component.
