| 摘要 |
PURPOSE:To improve heat exchanging efficiency by a mechanism wherein a heat exchanging portion consisting of an endothermic cylinder and an inner cylinder is mounted at the center of the bottom of a hot-water storage tank and the temperature of water and combustion gas in the heat exchanging portion is quickly brought close each other. CONSTITUTION:An endothermic cylinder 21 is penetrated at the cneter of the bottom of a hot- water storage tank 20, an upper end 211 is stretched up to a center portion and opened, and a lower portion is extended to a combustion chamber 12. An inner cylinder 22 is concentrically installed into the endothermic cylinder 21, the upper end 221 is opened to the side at a lower portion in the hot-water storage tank 20, and the lower end 222 is opened at a lower portion of a lower end portion of the endothermic cylinder 21. An endothermic fin 23 is disposed at a portion where the endothermic cylinder 21 extends in the combustion chamber 12. According to this construction, since cold water in the hot-water storage tank 20 is circulated and convected in the arrow head direction and preheated during the time when the cold water rises between the endothermic cylinder 21 and the inner culinder 22 and the quantity is little, the temperature of rising water and combustion gas is rapidly brought close each other, and temperature at a portion where both contact is maintained at a high temperature, thus improving operating efficiency. |
