METHOD FOR DETECTING BATHWATER REMAINING IN BATHTUB IN FULL AUTOMATIC HOT-WATER SUPPLIER

摘要

PURPOSE: To enable finding out whether or not bathwater remains in a bathtub by a method wherein water heated to a higher temperature than the temperature level appropriate for bathing is run through a circulating line and a change in the temperature in the circulating line before and after the start of a circulating pump is detected. ;CONSTITUTION: After heating water in a drum 2a to 70-80°C by a burner 6, a bathwater feed valve 12 in a hot-water supply line 10 is opened so that the heated water flows through lines 13, 14 and into both the bathtub 1 and a heat- exchange pipe 15 in a hot-water heater 2. The heated water run through the heat-exchange pipe 15 flows as circulating water through a three-way valve 7 and into the bathtub 1 by a lower circulating port 1b. Then a bath thermistor 5 provided in a circulating line 4 shows a rise in temperature to 60-70°C, thus functioning to detect the temperature in the circulating line 4. After starting a circulating pump 3 subsequently, by detecting a change in the temperature at this bath thermistor 5 it can be judged whether or not bathwater remains in the bathtub 1.;COPYRIGHT: (C)1993,JPO&Japio