| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a water heater capable of improving a energy saving performance by boiling depending on using state of quantity of heat and a controller used for the water heater. <P>SOLUTION: The controller 100 executes a boiling operation of a heat pump device 2 corresponding to required quantity of heat per day during a midnight time slot when an operation cost is inexpensive. During a daytime time slot except for the midnight time slot, the daytime time slot is divided by an hour and the heat pump device 2 is boiled for each divided time slot so as to secure a required quantity of heat for respective divided time slot. <P>COPYRIGHT: (C)2007,JPO&INPIT |
