摘要 |
Transfer waste water from wash cycle of dishwasher to collection tank beneath heat exchanger surrounding hollow central space, pass waste water through dual tube heat exchanger in countercurrent relation to cool feed water for hot water heater in central space of heat exchanger, supply heat to water in heater, then hot water to dishwasher rinse. May circulate feed water downwardly through outer space of heater, formed by partition, to lower end of inner space, in which heat is supplied by electrical immersion heaters. Ends of tank of hot water may be semi-oval, semi-elliptical or the like, while partition may be sufficiently close to bottom of tank to produce a wire-drawing effect as inlet water flows from outer to inner space, thereby maintaining light or small particles which fall off electric heaters in circulation, so that such particles will be removed with hot water. Heavier particles will collect in bottom of tank and may be drained periodically. |