(under subclass 476) Subject matter wherein the plural heating devices comprise two or more diverse types as set out above in this class.
SEE OR SEARCH THIS CLASS, SUBCLASS:
283, for liquid heater and associated nonliquid heater.
474, for plural function or convertible heaters which may comprise plural diverse electric heating devices.
484, for power supply, voltage or current regulation or current control means controlling diverse heating elements under the class definition and each having different resistance characteristics.
