1. An apparatus for heating fluids by magnetic induction comprising:a pair of interconnected heat exchanger elements configured generally parallel to one another, each formed as a generally closed ring with an internal hollow area, each having an inlet and an outlet configured for internal fluid flow, and each comprising a high electrically and thermally conductive metal surface, wherein the outlet of one of said pair is connected to the inlet of the other of said pair by external flexible tubing;
a rotatable disc for holding a plurality of magnets, wherein said disc is disposed generally parallel to, adjacent to, and between said heat exchanger elements, said disc generally shaped as a circular ring with a first face and an opposing face, said disc comprising a plurality of cavities, each said cavity configured to hold a magnet, said disc including a central hub located in the center of a diameter;
a plurality of magnets disposed in said rotatable disc, said plurality of magnets disposed with alternating polarity in said plurality of cavities, up to one magnet in each cavity, each said magnet disposed to be exposed to both of said first and said opposing faces; and
a frame for holding said heat exchanger elements and said rotatable disc, wherein said frame is configured to allow for adjusting the distance between at least one of said heat exchanger elements or a heat exchanger element and a face of said disc.