This shippable core is sized for a 6" exhaust flue and 55 gallon steel barrel. It includes the feed tube, burn tunnel, and heat riser.
Burning high fuel rates the top of the barrel will run between 600-700F with a 55 gallon barrel. With 2 30 gallon barrels the temperature will run between 500-650F. With a single 30 gallon the temperatures easily exceed 1000F. Therefore we recommend this core only be used with either a 55 gallon barrel or 2 30 gallon barrels.
The heat riser is 30" tall. The burn tunnel is 10 7/8" tall, 24" long, and 6 3/8" wide.
These are two slabs made from cast insulating refractory. One slab should be installed directly below the burn tunnel, then there should be an air gap of atleast 1" followed by the 2nd slab placed on the wood subfloor.