Abstract: The invention relates to a wall ring for receiving an axial fan in particular, comprising an annular body with a central longitudinal axis, a flow inlet opening, a flow outlet opening, and an electric heating element in particular, said heating element being arranged on at least some sections of the circumference of the annular body. A profiled covering section made of a thermally insulating material is removably fixed to an outer surface of the annular body at least in some sections of the circumference, said profiled covering section together with the annular body forming a receiving area in the region of the annular wall of the annular body in order to receive the electric heating element.