There is disclosed a method of preventing corrosion of the liquid contacting surface of a stainless steel base part of an electric liquid heating vessel. According to the method the surface is provided with a layer of glass, glass ceramic or ceramic. The surface is preferably pre-treated by grit blasting with alumina grit having a nominal size of 180-220 mesh. The grit blasting technique may be used to treat other steel surfaces which are to receive a glass layer.
