| 摘要 |
<p>PURPOSE:To provide a small-sized electrical hot water heater, facilitate to keep its mounting space and to reduce an electrical power fee by a method wherein an electrical heating means is provided with an electrical power receiving facility capable of supplying a mid-night electrical power and a day-time electrical power. CONSTITUTION:When a night-time electrical power applying time is not set but a day-time additional boiling is set to be allowed in a control means and a temperature of hot water heater is decreased down to an additional boiling start temperature, it is compared with a predetermined number of times of limitation. When an electrical heating is started within the limited number of times, an electrical heater is turned on to start a heating of hot water within a main body of a hot water heater. As a temperature of hot water is increased up to a heating completion temperature, the electrical heater is turned off and then the operation is returned back to its initial state. If a night-time electrical power supplying time is set and a sensor detects a temperature less than a heating starting temperature under a comparison with the set temperature of starting an additional boiling, the electrical heater is turned on to start a heating of the hot water within the main body of the hot water heater. After a temperature of the hot water is increased up to a temperature of completion of the heating operation, the electrical heater is turned off and then the operation is restarted.</p> |
