The invention relates to a heating module and a primary reflector for a heating module of a heating duct of a molding machine for producing containers from preforms, in which preforms made of thermoplastic are heated, which is provided between tubular heating units arranged in parallel and one over another on a side wall of the heating module and the side wall and consists of ceramic material, and is characterized in that the primary reflector is connected via a dovetail connection to the side wall, wherein a connecting region in the form of a dovetail is formed in each case on the reflector, which is fixable in each case with a clip made of steel, in particular spring steel, fastened on the side wall, having dimensions adapted to the dovetail.