| 摘要 |
<p>PREHEATING UNIT FOR DOMESTIC HOT WATER SUPPLY A preheating unit having a water tank provided with bottom, side and top walls. The tank is fitted with a cold water supply pipe and a warm water delivery pipe. A casing encloses the tank and has a side wall spaced from the side wall of the tank to provide a substantially annular insulating space therebetween. A plurality of inner tubes extend longitudinally through the tank and an outer tube is secured to the bottom and top walls to enclose each inner tube, The inner and outer tubes are spaced apart to define annular spaces therebetween. A lower adaptor on the casing connects a first pipe section to the pipe in communication with the inner tubes. An upper adaptor on the casing connects a second pipe section to the pipe in communication with both the inner tubes and the annular .spaces. The arrangement enables heat to be extracted from fluid gases and transferred to a domestic water supply with a minimum amount of harmful condensate collecting in the unit and this amount subsequently is evaporated and discharged to atmosphere.</p> |
