| 摘要 |
<p>A water heater with a water tank in which at least two heating devices which can operate switchably by a switchable device are provided. In order to safety, the switchable device is provided with a mechanism having non-return and brake functions. This invention uses a safety feature which has simple structure and is easy to instal. In addition to the heat device which can heat rapidly, an internal cylinder which can decrease heat loss is provided. Therefore this invention can truly meet the requirement of using water rapidly and in large amounts.</p> |
