| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent the freezing of a pipe by conducting the circulating operation without using a heater in a hot water storage type water heater. <P>SOLUTION: This device is constituted to prevent the freezing of the pipe by operating a three-way valve 23 at a tapping pipe side 3, a three-way valve 24 at a heat source return pipe side and a two-way valve 27 for pipe unit bypass 2, and conducting the circulation among a tapping pipe 6, a pipe unit bypass pipe 26, an inflow pipe 8, a low-temperature area at a lower part of the hot water storage tank 4, a heat source return pipe 7, a tank bypass pipe 25 and a heat source going pipe 9. In the flow channel, as the circulation is conducted by using a low-temperature water part at a lower part of the hot water storage tank 4 while preventing a high-temperature water part stored at an upper part of the hot water storage tank 4, thermal loss can be economically reduced, and the safety can be secured, as it is unnecessary to install a heater under a floor or the like. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
