Abstract: A through the wall insulated flue for low temperature venting of radiant heat from igniting combustibles produced by wood pellet, kerosene, fuel oil appliances such as stoves and hot water heaters. The flue assembly includes a protective metal tube, housing a ceramic insulated sleeve that is adapted to surround a flue pipe connected to the appliance, with the tube and insulating sleeve being of a length to be journalled through the wall for venting of the radiant heat. An inside wall plate and a complimentary outside wall plate provide necessary receiving collars for the opposite ends of the tube and insulating sleeve and function to correctly position them from internal wall structures.