| 摘要 |
<p>PURPOSE:To reduce the fluctuation of water temperature supplied to the hot water reservoir to the minimum so as to always deliver hot water at a suitable temperature by controlling the positional relationship between an electric heater and a second guide tube in response to the fluctuation of the pump delivery temperature so as to suitably set the hot water delivery temperature. CONSTITUTION:An air bubble pump 7 always monitors the hot water delivery temperature. If the delivery temperature is lower than the set temperature, an actuator 17 starts to move an electric heater 16 upwardly in response to the signal from a power supply control means in proportion to the temperature differential. When the electric heater 16 moves upwardly such that its upper end is higher than the outlet at the lower end of the second guide tube 14, the water supplied to the pump tube 8 is mixed with hot water therein, and the mixed hot water is again heated at the upper end of the electric heater 16. The hot water so heated to the set temperature is supplied to the hot water reservoir tank 1 from a hole 15 drilled in the upper part of the second guide tube 14 through an upper check valve 12 and an upper connecting pipe 10. In this instance, the hot water delivery temperature becomes increasingly higher as the electric heater 16 is moved higher because the reheating zone becomes longer.</p> |
