To solve a problem that hot water of high temperature at a lower part of a hot water storage tank flows into a pump when a thermistor is failed, which causes degradation of durability of the pump.
When an uppermost thermistor TH1 detects a temperature higher than a forth prescribed temperature, a circulation pump 3 is operated to lower the temperature of the uppermost thermistor TH1, and a control board 7 measures a time when the detection temperature by the uppermost thermistor TH1 is higher than the forth prescribed temperature, so that the circulation pump 3 is stopped to stop the power distribution to a heater 4 and to terminate a boiling-up operation, when the measured time is over a prescribed time.
COPYRIGHT: (C)2008,JPO&INPIT
FUJIBAYASHI SHINGO
FUJIMOTO TAKANOBU
| JP2004257582A | 2004-09-16 | |||
| JP2001343158A | 2001-12-14 | |||
| JP2001343161A | 2001-12-14 | |||
| JP2001194008A | 2001-07-17 | |||
| JPH10141771A | 1998-05-29 | |||
| JPH07286755A | 1995-10-31 | |||
| JPH07239153A | 1995-09-12 |
Hiroki Naito
Daisuke Nagano
Next Patent: PROTECTION CAP FOR HOT WATER PLUG