| 摘要 |
<p>PROBLEM TO BE SOLVED: To improve maintainability of water quality adjustment unit inhibiting scale precipitation.SOLUTION: A water heater comprises: a hot water storage tank 3; a water feed pipe 12 feeding water to a lower portion of the hot water storage tank 3; a heater 10 heating the water fed from the lower portion of the hot water storage tank 3 via a water inlet duct 18; a hot water outlet duct 19 in which the water heated by the heater 10 flows; and a water quality adjustment unit 23 detachably provided in the water inlet duct 18 or the water feed pipe 12, adjusting a water quality of the inflow water to a water quality that makes it difficult to generate scales, and discharging the resultant water. The water inlet duct 18 or the water feed pipe 12 includes: shutoff valves (25a and 25b) arranged on upstream and downstream sides of the water quality adjustment unit 23, respectively; a drain valve 26a arranged vertically downward of the water quality adjustment unit 23 between the two shutoff valves (25a and 25b); and an air intake device 31 provided vertically upward of the water quality adjustment unit 23 between the two shutoff valves (25a and 25b). Owing to this, it is possible to efficiently carry out maintenance of the water quality adjustment unit 23 without the need to drain the water from an entire system of the water heater.</p> |
