JPS6135877Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to hot water temperature control for a two-circuit hot water boiler that has circuits for both hot water supply to a bath or the like and heating such as hot water supply to a heating radiator.

In this specification, hot water supply from the hot water supply circuit is referred to as hot water supply, and hot water supply from the heating circuit is referred to as heating time.

To explain this kind of two-circuit hot water boiler with reference to Fig. 1, an inner shell 1 and an outer shell 2 constitute a hot water storage tank 3, a heating return port 4 which also serves as a make-up water port is provided at the bottom, and a heating outflow port 5 is provided at the top. . A hot water supply heat exchanger 6 is built in the upper part of the hot water storage tank 3, and water is supplied from an upper water inlet 7 and hot water is supplied from a lower hot water outlet 8. Reference numeral 9 denotes a heat-sensitive part (hereinafter referred to as a heating heat-sensing part) of a thermistor for detecting the temperature of the heating outlet of the temperature control device 10, which is provided near the heating outlet 5 and controls the burner 11.

The hot water supply heat exchanger 6 is of an indirect heating type using heated water in the hot water storage tank 3. In this configuration, when the water in the hot water storage tank is heated by the combustion heat of the burner 11, the heating heat sensitive section 9 senses the temperature, and when the temperature reaches the set temperature of the temperature control device 10, the burner 11 stops combustion. In other words, the boiler is in a boiling state.

When hot water is supplied by the hot water heat exchanger 6 from this state, the cold water supplied from the water supply port 7 exchanges heat with the boiling hot water in the hot water storage tank, becomes hot water, and is discharged from the tap 8. If hot water continues to be dispensed, the temperature of the water in the hot water storage tank will drop, the heating heat-sensitive section 9 will sense the temperature, and the burner 11 will re-combust. However, as mentioned above, since the hot water supply heat exchanger 6 uses an indirect heating method using the heated water in the hot water storage tank 3, the temperature of the hot water supply heat exchanger 6 is normally lower than the temperature of the hot water outlet 8 compared to the temperature of the hot water storage tank 3.
The temperature is 15-20℃ lower in the vicinity. In particular, as shown in FIG. 2, the above-mentioned temperature difference is at a maximum at point b, which is a little before point a when hot water starts to be tapped from the tap 8 and the temperature near the heating heat sensitive part 9 reaches the set temperature of the temperature control device 10. About
The temperature can reach up to 30℃. On the other hand, FIG. 2 shows the relationship between the height direction of the outer shell 2 and the wall surface temperature of the two-circuit hot water boiler during hot water supply. The heating heat sensitive section 9 is generally installed near the heating outlet 5 so that the temperature of the hot water supplied to the heating can be properly controlled during heating. In a two-circuit hot water boiler, as shown in FIG. 3, the temperature of the hot water storage tank above the hot water supply heat exchanger 6 is particularly high, and therefore the temperature of the outer shell wall surface in the vicinity is also high. Therefore, when hot water is supplied, the hot water temperature at the hot water outlet 8 is lower than the temperature of the outer shell wall surface to which the heating heat sensitive part 9 is attached, and may be 40 to 50 degrees Celsius lower when the water supply temperature is 10 degrees Celsius. Therefore, the temperature at point C, the lowest point of the hot water supply temperature in FIG. 2, is 30°C to 40°C. For this reason, when hot water is supplied to a bath or the like, "water comes out".

In order to increase the hot water supply temperature at point C, it is possible to increase the set value temperature of the temperature control device 10. However, if the system is started without being used for both heating and hot water supply, a boiling phenomenon will occur near the heating inlet 5, which is dangerous and may shorten the life of the hot water storage tank due to high-temperature corrosion. was.

The present invention has been made to solve the above problems. That is, when hot water is supplied, the temperature is detected and the set temperature of the temperature control device is increased.

The present invention will be explained below with reference to an embodiment shown in the drawings. The hot water heat exchanger 6 is installed on the outer shell wall surface where the temperature in FIG.
A heat sensitive part 12 of a thermistor for detecting the water supply temperature (hereinafter referred to as a hot water supply heat sensitive part) is provided. In FIG. 4, 9a is a negative characteristic thermistor of the heating heat sensitive section 9, and 12a is a negative characteristic thermistor of the hot water supply heat sensitive section 12. Both thermistors 9a and 12 have the same characteristics. 13 is a transistor, and 14 to 17 are resistors. 18 is an output terminal, the temperature control device is OFF at Hi level, and ON at Lo level.

According to this configuration, the OFF value of the temperature control device changes depending on the resistance value of the thermistor 12a. That is, the temperature near the heating heat sensitive part 9 is now high (resistance value is small).
When the resistance value of thermistor 12a is large (low temperature), the CN value of the temperature control device increases, and thermistor 1
If the resistance value of 2a is small, the temperature control device
The OFF value decreases. Therefore, if you start operation with neither heating nor hot water supply in use,
Since the temperature near the heating heat sensitive section 9 and hot water supply heat sensitive section 12 is high, the OFF value of the temperature control device is lowered, and boiling can be prevented. On the other hand, the heat sensitive part 12 for hot water supply during hot water supply
The temperature in the vicinity will drop rapidly due to the water supply from the water supply port 7, making it lower than the ambient temperature, so the temperature control device is
As the ON value increases and combustion starts earlier, the drop in hot water temperature can rise from the conventional point C to point C' as shown in Figure 2, and the phenomenon of "water coming out" can be prevented without causing boiling. It is something.

Note that the thermistor 12 for detecting the temperature of the water supply may be placed at any position as long as the temperature decreases as the water is supplied. For example, it is the pipe wall of the water supply port 7 near the outer shell 2.

In the above embodiment, the thermistors 9a and 12a are provided in parallel, but the thermistor 12 is connected to the characteristics and position of the hot water boiler and the characteristics of the thermistor 9a.
In relation to the characteristics of a, the transistor 13
The thermistor 9a is placed on the ground side from the base of the
It is also conceivable to provide 12a and 12a in series.

As described above, the present invention provides a temperature detection means for detecting the heating temperature, a water supply temperature detection means at a position where the temperature decreases due to water supply to the hot water heat exchanger, and outputs of both temperature detection means. The system is operated by inputting the water supply water, and is equipped with a temperature control device that increases the operating temperature by the output of the temperature drop from the latter feed water temperature detection means, so that the boiling temperature at the time of boiling can be reduced. It is possible to prevent this, and also to prevent the temperature of hot water from decreasing during hot water supply.

[Brief explanation of drawings]

Figure 1 is a vertical cross-sectional view of a conventional two-circuit hot water boiler, Figure 2 is a water supply characteristic diagram showing temporal changes in hot water temperature before and after improvement, and Figure 3 is a height direction of a two-circuit hot water boiler during hot water supply. FIG. 4 is a circuit diagram of a temperature control device according to an embodiment of the present invention. 3...Hot water storage tank, 4...Heating return port, 5...Heating outlet, 6...Hot water heat exchanger, 7...Water supply port,
8...Hot water supply port, 9...Thermal sensitive part for heating, 10...Temperature control device, 11...Burner, 9a...Thermistor for temperature detection with heating, 12...Thermal sensitive part for hot water supply,
12a...Thermistor for detecting water supply temperature, 18...
Output terminal.

Claims (1)

[Scope of Claim for Utility Model Registration] 1. In a two-circuit hot water boiler comprising a hot water storage tank constituting a heating circuit and a heat exchanger for hot water supply built into the hot water storage tank, a temperature detection means for detecting the temperature in the heating direction is provided, A water supply temperature detection means is provided at a position where the temperature decreases due to water supply to the hot water heat exchanger,
A temperature control device is provided which is operated by inputting the outputs of both of the temperature detection means and is configured to raise the operating temperature in accordance with the output of the temperature drop from the latter of the water supply temperature detection means. Features a 2-circuit hot water boiler. 2. In claim 1 of the utility model registration claim, both of the temperature detection means are thermistors, and the both thermistors are provided in parallel and are activated by the difference between the voltage at the connection point of both thermistors and the comparison voltage. A two-circuit hot water boiler comprising the temperature control device.