To feed hot water eliminated in its post-boiling into a bath tub when either water feeding or hot water feeding from a hot water feeding heat exchanger into the bath tub is started and to detect a flow rate of flowing of hot water without arranging an exclusive flow rate detecting sensor.
Post-boiling of hot water within a hot water feeding heat exchanger is judged by a post-boiling judgement section 32. A post-boiling elimination mixing control section 34 causes hot water and cold water to be mixed while opening a hot water flow rate control means GM1 for controlling a hot water flow rate with the hot water feeding heat exchanger being applied as a heat source and a bypass flow rate control means GM2 for controlling a flow rate in a water amount controlling bypass passage bypassing the hot water feeding heat exchanger when either cold water feeding or hot water feeding into the bath tub is started under the post-boiling state and further drops the hot water eliminated in its post-boiling into the bath tub. A mixing flow rate calculating section 35 attains through calculation a mixing flow rate dropped into the bath tub in reference to detected information of a hot water flow rate Q, information of water feeding temperature TIN and information about temperatures TK, TMIX before and after being mixed with water where a hot water flow rate passes through a water amount control bypass passage.
| JPS60240961 | DRAINING DEVICE OF WATER HEATER |
| JP3441551 | HOT WATER FEEDER |
SAITO TOSHIHISA
SATO TETSUYA
