| 摘要 |
PROBLEM TO BE SOLVED: To obtain a storage type hot water supply apparatus, in which a contract is made according to a time zone electric lighting rate system, hot water is boiled by utilizing the night-time zone of relatively low electric lighting rate principally, and water in a tank is boiled efficiently at a low rate utilizing complementarily the high rate daytime zone. SOLUTION: The storage type hot water supply apparatus makes a contract according to a time zone electric lighting rate system utilizing daytime power and midnight power. At night-time zone, hot water in a tank is boiled through heat pump heat collecting operation and at daytime zone, hot water in the tank is boiled through solar heat collecting operation or heat pump heat collecting operation. |
