| 摘要 |
PROBLEM TO BE SOLVED: To reduce a maintenance cost for a hot water supply device for a drink by a method wherein a large capacity first hot water supply apparatus to utilize a midnight power and a small capacity second hot water supply apparatus through constant electrical connection are connected to each other in series. SOLUTION: A second hot water supply apparatus 8 is arranged at the upper part of a first hot water supply apparatus 7. A first heating means 10 is arranged at the internal part of a large capacity closed type tank 9 and a second heating means 19 is arranged at the internal part of a small capacity release type tank 18 of a second hot water supply apparatus 8. At a midnight time zone, the tank 9 is boiled by the first heater 10. In this case, when a temperature sensor 40 being a hot water temperature detector detects a temperature below a specified value, energization of the second heater 19 is effected in priority and the first heater 10 is stopped. The tank 18 is always kept in a hot water state by the second heater 19. In this case, by pressing a switch 39 for hot water supply, hot water is supplied through a hot water supply port. By pressing the switch 39 again, supply of hot water is stopped. In this case, since previously boiling hot water in the tank 9 flows in the tank 18, a heating load does not occurs. |
