Abstract: A centrifugal fan comprises a volute casing having an electric motor, controlled by a control module, coupled to an impeller mounted in the center of the volute, whereby to force air through the volute. In a predetermined zone of the volute, there is at least one deflecting wall or baffle, the curvature of which is substantially the same as that of this zone. The casing carries fastening means which are arranged to retain at least an element of the control module in a position in which this control module element is substantially integrated with the deflecting baffle. The air flowing in the volute can thus pass over the control module element, so as to cool the latter, without the air stream undergoing any significant perturbation.