outdoor wood furnace outdoor wood boiler design corn burning boiler OUTDOOR WOOD FURNACE The Empyre outdoor wood furnace is designed to provide hot water for baths and showers. The hot water is stored in the hot water tank. The hot water is heated through a side arm heat exchanger mounted to the side of the hot water tank. Washing hands can be a pleasure with the sense of comfort knowing that you are heating with your own Empyre outdoor wood furnace.