Caloritech™ CX Replacement Boiler Flange Heaters are registered Caloritech™ quality replacements for boilers of the highest commercial grade available anywhere. Replacement boiler flange heaters are available in a range of sizes and styles to suit the requirements of different boiler units, including rectangular flanges, square flanges, and round flanges. Please consult the Catalog for detailed information on the available wattages, voltages, flange styles and heater sizes that are suitable for your boiler unit.