JPH0148465B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a hot water supply capacity switching device for a water heater.
A signal from a temperature sensing element that conventionally detects the temperature of hot water,
A system for controlling burner combustion by comparing a signal from a temperature setting device is known, for example, from Japanese Utility Model Publication No. 58-23088.

However, with this device, priority is set for the temperature setting device, and the hot water temperature from all taps is maintained at the temperature set in the temperature setting device with the highest priority. As long as the vessel is selected, the hot water temperature will remain at that temperature. Therefore,
For example, after selecting the hot water temperature suitable for a shower using the highest priority temperature setting device, even if it is necessary to supply hot water to a bath, there is an inconvenience that only lukewarm water is obtained.

In view of the current situation, it is an object of the present invention to make it possible to obtain high-temperature hot water as needed. In the device that controls the combustion of the burner by comparing the The first temperature setting device is selected, and when water flow is stopped, the selection is canceled and the second temperature setting device is selected.

In the drawing, 1 is a water heat exchanger interposed in a waterway 4 connecting a tap 2 and a water source 3, 5 is a gas burner that heats the water heat exchanger 1, and 6a is interposed in a gas supply path 6 of the gas burner 5. The second gas control valve 6a is equipped with a thermistor 7 as a temperature sensing element for detecting the temperature on the outlet side of the water heat exchanger 1.
It is controlled by a temperature control circuit as shown in the figure.

As is generally known in the past, this temperature control circuit constitutes a bridge circuit with fixed resistors 8 and 9, the thermistor 7, and a temperature setting device 10.
and the thermistor 7 are connected to the positive input terminal of the comparator 11, and the connection points of the fixed resistor 9 and the temperature setting device 10 are connected to the negative input terminal of the comparator 11, and when the potential of the positive input terminal is high, An output is obtained from the comparator 11, conduction is established between the emitter and collector of a transistor 12 as a switching element, and a gas solenoid valve or comparison control valve 13 connected to the collector of the transistor 12 is controlled.

So far, there is no particular difference from the conventional example. In such a case, the present invention includes a first temperature setting device 10a which maintains the hot water temperature at a constant high temperature, and a second temperature setting device 10a which can set the hot water temperature to an arbitrary temperature lower than that. The first temperature setting device 10a is connected to the bridge circuit through the normally open contact 15b of the changeover switch 15a, which is connected to the relay 15 in series with the push button type hand switch 14. Built-in and normally closed contact 15
The second temperature setting device 10b is incorporated into the bridge circuit via the bridge circuit c.

Further, the relay contact 15d of the relay 15 is inserted in parallel with the hand switch 14, and these are connected to the power source 17 via the flow switch 16. For example, as shown in Figure 1,
When hot water is filled by dropping from the hot water tap 2 If the temperature of the hot water is low, open the hot water tap 2 to pour hot water and press the hand switch 14, the relay 15 will be energized, and the interlocked switch 15a will be turned on. High temperature first
temperature setting device 10a and relay 15.
is in a self-held state by its contact 15d.

Therefore, the combustion of the gas burner is controlled so that high output can be obtained, and the hot water from the tap 2 is heated to a high temperature, for example.
You can get hot water between 75 degrees C and 80 degrees C.
When the tap 2 is closed, the flow switch 16 is opened and the relay 15 is de-energized.

Therefore, the switch 15 linked to the relay 15
a is switched to the second temperature setting device 10b which can set any temperature below the first temperature.

Therefore, when the hot water tap 2 is subsequently opened, hot water at the temperature set in the second temperature setting device 10b is obtained, thereby preventing inconveniences such as burns.

In this way, according to the present invention, hot water at a high temperature can be obtained by operating the hand switch as necessary, and when hot water is turned off, hot water can be obtained at an arbitrary temperature lower than that. Since the water is constantly changing, you can use it safely without getting burnt the next time you tap the hot water.

[Brief explanation of drawings]

Fig. 1 is a system diagram of one example of implementing the present invention;
The figure is a control circuit diagram. 7... Temperature sensing element, 10... Temperature setting device, 14...
...hand switch.

Claims (1)

[Claims] 1 A signal from a temperature sensing element that detects the hot water temperature,
In the device that controls the combustion of the burner by comparing the signal from the temperature setting device, the temperature setting device is made of two devices, a first and a second, which can be set to a certain high temperature and an arbitrary temperature below that temperature. , by operating the hand switch
A hot water supply capacity switching device for a water heater, characterized in that the second temperature setting device is selected, and when water flow is stopped, the selection is canceled and the second temperature setting device is selected.