A heated vent cap assembly is provided which can be coupled to a pipe originating from a plumbing system within a building. A heating element is wound around an inner cylinder which is wrapped in a conductive foil and enveloped by a larger diameter outer cylinder which is lined with a reflective foil defining a void there between. The cylinders are secured at an upper end by an end cap and at a lower end by a lower end cap and a tether is tautly secured within the inner cylinder by a bridge in an opening of the end cap and a lower disk engaged with the lower end of the inner cylinder to support ice blocks formed therein. The heating cable generates heat, which is reflected by the reflective foil and absorbed by the conductive foil to prevent ice from forming on the inner surface of the inner cylinder.