JP3785197B2 - Solar hot water heater - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a gas water heater using a solar water heater.
[0002]
[Prior art]
In recent years, a gas hot water supply device combined with a solar water heater has been developed. FIG. 1 shows an example. When the temperature Ta of the solar hot water is lower than the set temperature Td, the heat exchanger 1 heats it with the burner 7, and when the solar hot water Ta is higher than the set temperature Td, the burner 7 is heated. Is not ignited, and tap water is mixed with solar hot water by a mixing valve (commonly known as Q valve) 3 with a temperature setting function to obtain an appropriate temperature. According to this configuration, it can also be applied to a fully automatic bathtub water heater with an “automatic hot water beam” function, so that hot water is poured directly from the solar water heater into the bathtub and then refilled or filled with water. Compared to the method, the user can put hot water in the bathtub with a single button operation, there is no worry of forgetting to stop the hot water or emptying, and the temperature of the hot water in the bathtub is uniform and does not need to be stirred. There is an advantage.
[0003]
[Problems to be solved by the invention]
However, in the conventional configuration of FIG. 1, the hot water temperature from the solar water heater sometimes rises to 85 to 90 ° C. When this is supplied directly to the heat exchanger 1, it is used for sealing pipe connections and the like. The O-ring is deteriorated and the life of the flow sensor is shortened. However, in order to avoid this, as shown in FIG. 2, the method of mixing solar hot water and tap water upstream of the heat exchanger 1 is to mix the hot water tap and the hot water temperature of the shower far away from the hot water tap. Since the control is performed by controlling the valve 2 and the burner 7, there is a problem that the response is poor and it takes time until the hot water temperature is stabilized. An object of the present invention is to solve the above-described problems, and to provide a solar water heating hot water supply apparatus that has no risk of deteriorating the seal of the heat exchanger 1 and the like with solar hot water and that has good responsiveness.
[0004]
As shown in FIG. 3, the solar heat utilization gas hot water supply apparatus according to the present invention includes a heat exchanger 1 interposed in a solar hot water pipe 4 and a bypass pipe 5 branched on the upstream side of the heat exchanger 1. When the temperature of the solar hot water detected by the temperature sensor 8a, which is recombined by the three-way switching valve 6 on the downstream side of 1 and arranged upstream of the portion where the bypass pipe 5 of the solar hot water pipe 4 branches, exceeds a certain value. The three-way switching valve 6 is switched so as to flow to the bypass pipe 5, and the Q valve 3 for mixing tap water is provided downstream of the three-way switching valve 6.
[0005]
According to the configuration of FIG. 3, when the solar hot water is lower than the set temperature (for example, 42 ° C.) (for example, 30 ° C.), it is heated by the heat exchanger 1, and the solar hot water is higher than the set temperature (for example, 50 ° C.). Since the tap water is mixed with the Q valve 3 without igniting the burner 7 and the solar hot water is higher than a certain temperature (for example, 60 ° C.), it can be bypassed without passing through the heat exchanger 1 . There is no possibility of deteriorating the seal portion, and since the Q valve 3 is used, there is no problem in responsiveness.
[0006]
【Example】
FIG. 3 shows an embodiment, in which a heat exchanger 1 is provided in a solar hot water pipe 4 to which hot water is supplied from a solar water heater, and a bypass pipe 5 branched from the upstream side of the heat exchanger 1 is heated. A mixing valve with a temperature setting function that mixes tap water with hot water from the heat exchanger 1, that is, a Q valve 3, is recombined by the three-way switching valve 6 on the downstream side of the exchanger 1. When the temperature Ta of the solar hot water exceeds a certain value, the three-way switching valve 6 is switched so that the solar hot water flows to the bypass pipe 5. In the figure, 8a, 8b, 8c and 8d are temperature sensors, and a control device (not shown) controls the mixing ratio of the valves 2 and 3 based on the temperature data from these temperature sensors 8a to 8d. ing.
[0007]
In FIG. 3, when the temperature Ta of the solar hot water is lower than the set temperature Td (for example, 40 ° C.) but higher than the temperature Tb of the tap water, it is passed through the heat exchanger 1 to 60 ° C. with the heat exchanger 1. Heat and adjust to 40 ° C. with Q valve 3. Next, when the solar hot water is higher than the set temperature (for example, 50 ° C. ), the hot water is simply passed through the heat exchanger 1 and the burner 7 is not ignited. Further, when the solar hot water is at a certain temperature (for example, 60 ° C.) or higher, the heat exchanger 1 is not passed through, but is passed through the bypass pipe 5 and adjusted to an appropriate temperature by the Q valve 3. If comprised in this way, since very hot (for example, 60 degreeC or more) hot water does not pass through the heat exchanger 1, there is no possibility of deteriorating a seal part, and the hot water temperature is always at hand Q. Since it is adjusted by the valve 3, the responsiveness is very good.
[0009]
【The invention's effect】
The invention as described above, since it is obtained by branching the bypass pipe 5 from solar water pipe 4 upstream of the heat exchangers 1, the tube connection portion of the heat exchanger 1 as in the conventional example of FIG. 1 The problem that the sealing O-ring used deteriorates due to high temperature can be solved, and the temperature is adjusted by the Q valve 3 in the vicinity of the hot water tap or shower, so that the temperature control response is good. As in the conventional example of No. 2, there is an advantage that the hot water temperature does not become unstable and does not cause hunting.
[Brief description of the drawings]
FIG. 1 is a system diagram of a conventional example.
FIG. 2 is a system diagram of another conventional example.
FIG. 3 is a system diagram of an embodiment of the present invention.
[Explanation of symbols]
1 Heat exchanger 2 Mixing valve 3 Mixing valve with temperature setting function or (Q valve)
4 Solar hot water piping 5 Bypass piping 6 Three-way selector valve 7 Burners 8a to 8d Temperature sensor 9 Tap water piping

Claims (1)

A heat exchanger is installed in the solar hot water pipe, and the bypass pipe branched on the upstream side of the heat exchanger is recombined by a three-way switching valve on the downstream side of the heat exchanger to branch the bypass pipe of the solar hot water pipe When the temperature of the solar hot water detected by the temperature sensor located upstream of the part exceeds a certain value, the three-way switching valve is switched so that it flows through the bypass pipe without passing through the heat exchanger, and further downstream of the three-way switching valve. A solar-powered gas water heater with a mixing valve with a temperature setting function that mixes tap water.

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