JPH09138006A - Solar heat water-heater facility - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solar heat water heater facility which does not exceed hot water temperature in a solar heat water heater at 100 deg.C even if the pressure of the heater is set to 1kg/cm<2> or more. SOLUTION: A second communicating tube 22 for communicating a water supply tube 11 with a hot water supply tube 12 is provided at the position of lower site than a solar heat water heater 10 at the side of the heater 10 from a first communicating tube 21, and a pump 23, a first warm water pressure valve 24 and a first flow switch 25 are provided at the tube 22. Further, a drain pipe is coupled to the valve 24 to drain the hot water near the ground surface. A second warm water pressure valve 26 is provided at the hot water outlet 10b of the heater 10. And, a temperature sensor 27 for detecting the hot water temperature in the heater 10 to control the operation of the pump 23 is inserted into the outlet 10b of the heater 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solar hot water supply system for supplying hot water using solar heat.

[0002]

2. Description of the Related Art FIG. 2 is a system diagram showing an example of conventional solar hot water supply equipment.

In the figure, a water supply pipe 11 for supplying water to the solar water heater 10 is connected to a water supply port 10a of the solar water heater 10, and a hot water supply pipe 12 for taking out hot water from the solar water heater 10 is provided. It is connected to the hot water supply port 10b of the solar water heater 10. A pressure reducing valve 13 is attached to the water supply pipe 11 at a position lower than the solar water heater 10.

On the secondary side of the pressure reducing valve 13, there is provided a communication pipe 14 for connecting the water supply pipe 11 and the hot water supply pipe 12 at a position lower than the solar water heater 10, and the communication pipe 14 and the hot water supply pipe 1 are provided.
A mixing valve (hot and cold water mixing valve) 15 is provided at the connecting portion of 2.
Is provided. Connection part 1 of communication pipe 14 and water supply pipe 11
The water supply pipe 11 between the solar water heater 1a and the solar water heater 1a is provided with a first check valve 16 that allows a flow from the pressure reducing valve 13 to the solar water heater 10 and prevents a reverse flow. There is. A second check valve 17 for allowing the flow from the water supply pipe 11 to the hot water supply pipe 12 to the communication pipe 14 and preventing the flow in the opposite direction.
Is provided. In addition, the outlet 1 of the mixing valve 15
5a is provided with a third check valve 18 which allows the flow of the mixed water in the outgoing direction and prevents the flow in the reverse direction. Further, a pressure relief valve 19 is attached to the hot water outlet 10b of the solar water heater 10, and a drainage pipe (not shown) is connected to the pressure relief valve 19 so that the hot water flows along the roof surface. It is designed to be flushed.

The set pressure of the pressure relief valve 19 is set higher than the set pressure of the pressure reducing valve 13, and for example, the pressure relief valve 19 is set.
Set pressure of, 0.95kg / cm ^2, the set pressure of the pressure reducing valve 13 is set to 0.8 kg / cm ^2.

The water supplied to such a solar water heater 10 is heated by solar heat and expands when the temperature rises, and the water pressure in the solar water heater 10 rises. When the set pressure of the pressure relief valve 19 provided at the hot water outlet 10b is reached, hot water is discharged from the pressure relief valve 19 to the outside through the drainage pipe, and the solar water heater 10
Decrease the pressure inside. That is, the pressure in the solar water heater 10 does not exceed the set pressure of the pressure relief valve 19.

In such a solar hot water supply facility, tap water is supplied from the pressure reducing valve 13 through the water supply pipe 11 to the solar water heater 10 and then filled in the hot water supply pipe 12 and the communication pipe 14. In this state, when pumped for a certain period of time during the day, the water in the solar water heater 10 is heated by the solar heat to become hot water, and the hot water supply pipe 12 causes the hot water outlet 15 of the mixing valve 15 to flow.
It is taken out to the outside through b, the outlet 15a, and the third check valve 18.

At this time, the same amount of water as the hot water flowing out from the solar water heater 10 is supplied to the solar water heater 10 from the water supply pipe 11. Further, the water that has passed through the pressure reducing valve 13 also enters the water port 15c of the mixing valve 15, the hot water and the water are mixed in the mixing valve 15, and the hot water of the set temperature comes out from the outlet 15a. The hot water extracted in this way is used directly for hot water supply, or when it is raining or snowing, etc.
When the hot water inside is low, it is reheated with gas or oil water heaters before it is used.

[0009]

Conventionally, solar water heaters have been used at a pressure of 1 kg / cm ² or less. For example, in the case of the above-mentioned solar water heater, the pressure inside the solar water heater is 0.95 which is the set pressure of the relief valve
It does not exceed kg / cm ² .

However, in recent years, direct pressure type gas / oil water heaters have become widespread, and the use of hot water on the second floor or the simultaneous use of hot water at multiple locations is increasing. Along with this, the hot water supply pressure of the solar water heater is increased. Otherwise it wouldn't work enough.

That is, when a solar water heater having a pressure of 1 kg / cm ² or less is connected to a direct pressure type gas / oil hot water supply device, there is a problem that the hot water in the kitchen is poor or the water from the shower is poor.

Under these circumstances, 1 kg of solar water heater
Although it is desired to use at a pressure of / cm ² or more, when using a solar water heating system with such a high pressure, the hot water temperature may exceed 100 ° C., and as a result, the constituent members are likely to deteriorate. The problem arises.

For example, the pressure reducing valve 13 of the solar hot water supply facility shown in FIG.
With a set pressure of 2.5 kg / cm ² and a set pressure of the pressure relief valve 19 of 3 kg / cm ² , using a vacuum glass tube type solar water heater with a hot water storage capacity of 240 liters and an effective heat collection area of 2.73 m ² . Solar water heater 10 on a sunny summer morning
If tap water of about 30 ° C. is supplied to the inside of the solar water heater and the hot water in the solar water heater 10 is left untouched all day long, the maximum temperature reached is about 84 ° C. If you carry on the next day without using hot water at all, the natural temperature of the night will keep the temperature of the hot water the next morning.
Although it will be about 60 ° C., the next day will be sunny again, and if the hot water is not used at all during the daytime, the maximum attainable temperature of the hot water in the solar water heater 10 will be about 113 ° C. Similarly, if the hot water is left unused for the third day, the maximum temperature reached by the hot water in the solar water heater 10 will be about 130 ° C.

In this way, if the performance of the solar water heater 10 is good, if the hot water is not used at all on sunny days, the maximum temperature of the hot water in the solar water heater 10 is set by the pressure relief valve 19. The pressure may rise to a temperature at which it becomes saturated vapor pressure.

The present invention has been made in view of the above circumstances, and even if the pressure of the solar water heater is 1 kg / cm ² or more, the water temperature in the solar water heater does not exceed 100 ° C. The purpose is to provide.

[0016]

The solar hot water supply equipment of the present invention is a solar water heater for heating water by utilizing solar heat, and a water supply pipe for connecting to a water inlet of the solar water heater to supply water to the solar water heater. And a solar hot water supply equipment comprising a hot water supply pipe connected to the hot water outlet of the solar water heater to take out hot water from the solar water heater, wherein a pressure reducing valve is provided on the water supply pipe at a position lower than the solar water heater. Provided on the secondary side of the pressure reducing valve and at a position lower than the solar water heater, a first communication pipe for communicating the water supply pipe and the hot water supply pipe is provided, and mixing is provided at a connection portion between the first communication pipe and the hot water supply pipe. A valve is provided, and a second communication pipe for communicating the water supply pipe and the hot water supply pipe is provided on the solar water heater side of the first communication pipe and at a position lower than the solar water heater.
A pump, a first warm pressure valve and a first flow rate switch are provided in the communication pipe of, a second flow rate switch is provided at the mixed water outlet of the mixing valve, and a second heat pressure valve is provided at the outlet of the solar water heater. A temperature sensor that detects the hot water temperature of the solar water heater and controls the operation of the pump is provided, and the set pressure of the pressure reducing valve is set lower than the set pressure of the first warm pressure valve and the second warm pressure valve, and The setting pressure of the warm pressure valve of 2 is lower than the setting pressure of the second warm pressure valve, the preset temperature of the temperature sensor for starting the pump is lower than the preset temperature of the first warm pressure valve and the second warm pressure valve, and , The set temperature of the first warm pressure valve is set lower than the set temperature of the second warm pressure valve, and the first flow rate switch and the second
It is characterized in that the operation of the pump is controlled by the flow rate switch.

Further, according to the present invention, a flow from the pressure reducing valve to the solar water heater is allowed in the water supply pipe between the first communication pipe and the water supply pipe connecting portion and the second communication pipe and the water supply pipe connecting portion. However, the first check valve for preventing the flow in the reverse direction is provided, and the second check pipe for allowing the flow from the hot water supply pipe to the water supply pipe in the second communication pipe to prevent the flow in the reverse direction. It is characterized in that a valve is provided and a third check valve is provided in the hot water supply pipe near the outlet of the mixing valve to allow the flow of the mixed water in the direction of exit and prevent the flow in the opposite direction.

Furthermore, the present invention is characterized in that a drain valve is provided on the secondary side of the third check valve.
A feature is that a strainer is provided on the water supply pipe on the next side, and the set temperature of the temperature sensor for starting the pump is 70
It is characterized in that the temperature is not less than 0 ° C and not more than 90 ° C.

[0019]

In the solar hot water supply system of the present invention, even if the solar water heater is used at a pressure of 1 kg / cm ² or more, the solar water heater is left for two days or more without any hot water on a sunny day in summer. When the temperature of the hot water inside rises and reaches the temperature at which the pump starts, the pump operates and the hot water in the solar water heater
It is cooled while circulating from the hot water supply pipe to the water supply pipe through the second communication pipe.

However, if the solar water heater is installed under the condition that the water supply pipe or the hot water supply pipe is short, or if the water supply pipe or the hot water supply pipe is covered with a thick heat insulating material and the cooling capacity is small, Even if the water circulates, the hot water temperature in the solar water heater may gradually rise, but when the hot water temperature reaches the set temperature of the first hot pressure valve, hot water is discharged from the first hot pressure valve,
The same amount of water as that discharged is newly supplied from the pressure reducing valve to the solar water heater through the water supply pipe, and is mixed with the hot water to lower the hot water temperature. The first hot-pressure valve is installed at a position lower than the solar water heater, and normally, a drain pipe is connected to the first hot-pressure valve so that hot water can be safely discharged near the ground.

If the circulation function does not work due to a power failure or pump failure, the hot water temperature in the solar water heater rises to the set temperature of the second hot pressure valve provided at the outlet of the solar water heater. At this time, too, hot water is discharged from the second hot pressure valve, and the same amount of water as the discharged amount is newly supplied from the pressure reducing valve to the solar water heater via the water supply pipe and mixed with the hot water. It will lower the temperature. That is, in the solar hot water supply equipment of the present invention, the first hot-pressure valve is normally operated to maintain the hot water temperature at or below the set temperature, but the second hot-pressure valve is provided in consideration of safety in case of emergency. Have been.

Further, according to the present invention, the second flow pipe is provided with the first flow rate switch so that the pump is stopped when the water is not circulated during the operation of the pump. That is, if the solar hot water supply equipment is used for a long period of time, the pump may bite dust or the inside of the water supply pipe, the hot water supply pipe and the second communication pipe may be blocked by rust, dust, or the like. If the pump continues to operate as described above, there is a risk of failure. However, by operating the first flow rate switch, it is possible to prevent the failure of the pump and detect that there is an abnormality in circulation.

Further, according to the present invention, a second flow rate switch is provided at the mixed water outlet of the mixing valve so that the pump is stopped when hot water is used in a bath or kitchen. That is, when hot water is used in a bath or kitchen, water does not newly flow into the solar water heater and the hot water in the solar water heater does not rise to 100 ° C or higher, so there is no need to operate the pump. Because. Moreover, when water is circulated by the pump, the hot water is divided into two parts, the mixing valve side and the pump side, and the amount of hot water supplied to the bath or kitchen is reduced, which is not preferable.

In the solar hot water supply system of the present invention, the pressure reducing valve to the solar water heater is connected to the water supply pipe between the first communication pipe and the water supply pipe and between the second communication pipe and the water supply pipe. A first check valve that allows the flow and prevents the flow in the reverse direction is provided, and a second check valve that allows the flow from the hot water supply pipe to the water supply pipe in the second communication pipe and prevents the flow in the reverse direction. If a non-return valve is installed and a third check valve is installed to allow the flow of mixed water in the hot water supply pipe near the outlet of the mixing valve and prevent the flow of water in the reverse direction When an unforeseen situation occurs, it is possible to prevent the water from flowing back to the main side.

If a drainage valve is provided on the secondary side of the third check valve, the hot water in the solar water heater can be manually drained from the drainage valve or the temperature of the drained hot water can be measured. This is preferable because it is possible to confirm the set temperature of the mixing valve.

Further, it is preferable to provide a strainer on the water supply pipe on the primary side of the pressure reducing valve, because foreign matters such as dust in tap water can be removed to prevent foreign matter biting accidents such as the pump and the hot pressure valve.

The first hot pressure valve and the second hot pressure valve of the solar hot water supply equipment of the present invention act as safety valves for temperature and pressure, and a temperature adjusting valve and a pressure relief valve may be used together. It is possible.

In the solar hot water supply system of the present invention,
If the set temperature of the temperature sensor that activates the pump is too low, the amount of heat obtained by the solar water heater will be wasted, and if the set temperature of the temperature sensor is too high, the set temperature of the first hot pressure valve will be lost. Since there is no difference with
It is desirable that the temperature is 70 ° C. or higher and 90 ° C. or lower.

Further, in the solar hot water supply system of the present invention, if a plurality of second hot-pressure valves are installed, even if one hot-pressure valve fails, the other hot-press valves operate normally, so that safety is increased. Become.

[0030]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a solar hot water supply system of the present invention will be described in detail based on embodiments.

(Embodiment 1) FIG. 1 is a system diagram showing a solar hot water supply facility of the present invention. The same components as those of the solar hot water supply system in FIG. 2 are given the same numbers.

As the solar water heater 10, for example, as disclosed in Japanese Patent Publication No. 3-56387, a transparent long cylindrical glass container having a vacuum inside is provided with a selective absorption film on the outer surface. It is possible to use one in which a plurality of heat collecting hot water storage pipes, which are formed by coaxially arranging coated cylindrical metal hot water storage containers, are arranged, and the hot water storage amount is 240 liters and the effective heat collecting area is 2.73 m ² .

This solar water heater 10 is installed on a roof of a building with a predetermined inclination angle, a water supply pipe 11 is connected to a water supply port 10a of the solar water heater 10, and a hot water supply pipe 12 is an outlet of the solar water heater 10. It is connected to the sprue 10b. A pressure reducing valve 13 is attached to the water supply pipe 11 at a position lower than the solar water heater 10 (close to the ground).
A strainer 20 is provided on the next side, and the strainer 20
The primary side water supply pipe 11 is connected to the main tap of the water supply.

In the immediate vicinity of the secondary side of the pressure reducing valve 13, a first communication pipe 21 for connecting the water supply pipe 11 and the hot water supply pipe 12 is provided, and the connecting portion between the first communication pipe 21 and the hot water supply pipe 12 is provided. A mixing valve 15 is provided in the. The water supply pipe 11 and the hot water supply pipe 1 are provided on the solar water heater 10 side of the first communication pipe 21 and at a position lower than the solar water heater 10.
A second communication pipe 22 for communicating the two is provided, and the second communication pipe 22 is provided with a pump 23, a first temperature / pressure valve 24, and a first flow rate switch 25. Further, a drainage pipe (not shown) is connected to the first temperature / pressure valve 24 so that the hot water can be discharged near the ground.

The hot water outlet 10b of the solar water heater 10 is provided with a second hot pressure valve 26 and a temperature sensor 27 for detecting the hot water temperature in the solar water heater 10 and controlling the operation of the pump 23. Has been inserted. A drain pipe (not shown) is also connected to the second temperature / pressure valve 26 so that hot water flows along the roof.

The connecting portion 1 between the first communication pipe 21 and the water supply pipe 11
1a, a connecting portion 11b between the second communication pipe 22 and the water supply pipe 11
Between the pressure reducing valve 13 and the solar water heater 1
A first check valve 28 that allows the flow to 0 and prevents the flow in the opposite direction is provided, and the second communication pipe 22 allows the flow from the hot water supply pipe 12 to the water supply pipe 11. A second check valve 29 for preventing reverse flow is provided, and a direction in which mixed water flows out from the second flow rate switch 30 and the mixing valve 15 to the hot water supply pipe 12 near the outlet 15a of the mixing valve 15. Is provided and a third check valve 31 is provided to prevent the flow in the reverse direction. Also, the third check valve 3
A drainage pipe 32 is connected to the hot water supply pipe 12 on the secondary side of 1, and a drainage valve 33 is attached to the drainage pipe 32. The detected flow rate of the first flow rate switch 25 and the second flow rate switch 30 is 3.5 liters / minute.

The lengths of the water supply pipe 11 and the hot water supply pipe 12 of this solar hot water supply facility are each about 10 m, and are connected by a cross-linked polyethylene pipe without heat insulation. The set temperature of the mixing valve 15 is appropriately determined according to the hot water supply application and the type of gas / oil hot water supply equipment, but is generally 30 to 65 ° C.
The hot water temperature is adjusted.

Next, an example of using this solar hot water supply facility will be described.

First, the set pressure of the pressure reducing valve 13 is set to 2.5 kg /
cm ² , set pressure of the first warm pressure valve 24 to 3.0 kg / c
m ² , the set pressure of the second hot pressure valve 26 is 3.5 kg / cm
^{And 2} . In addition, a temperature sensor 27 that controls the pump 23
The set temperature was set to 80 ° C. for starting the pump 23 and 75 ° C. for stopping the pump 23. Further, the set temperature of the first warm pressure valve 24 was set to 90 ° C, and the set temperature of the second warm pressure valve 26 was set to 95 ° C.

Thus, when the tap water at about 30 ° C. is supplied from the pressure reducing valve 13 to the solar water heater 10 through the water supply pipe 11 on a sunny day in the summer and left without using hot water at all, in the afternoon, the solar water heater is used. The hot water in the vessel 10 reached 80 ° C, the temperature sensor 27 detected 80 ° C, and the pump 23 was activated.

When the pump 23 is activated, the hot water circulation path is: pump 23 → second communication pipe 22 → water supply pipe 11 → solar water heater 10 → hot water supply pipe 12 → second communication pipe 22 → pump 23 The circulation flow rate was about 8 liters / minute. Then, in the evening, the temperature of the hot water in the solar water heater 10 drops,
Then, the temperature sensor 27 again detected 75 ° C., and the pump 23 stopped.

The maximum temperature of hot water in the solar water heater 10 during pump operation was about 81 ° C., and the amount of solar radiation on this day was about 4800 kcal / m ² · day.

Then, if the water was left as it was at night without using hot water, it was naturally cooled and the hot water temperature of the next morning was about 63 ° C.
If the hot water is left without using it, the temperature of the hot water in the solar water heater 10 becomes 80 ° C at noon, and the temperature sensor 2
7 detected 80 ° C., and the pump 23 was activated. In the evening, when the temperature of the hot water in the solar water heater 10 dropped to 75 ° C., the temperature sensor 27 detected again and the pump 23 stopped.

The maximum temperature of hot water in the solar water heater 10 during pump operation was about 86 ° C., and the amount of solar radiation on this day was about 5200 kcal / m ² · day.

(Embodiment 2) The same as Embodiment 1 except that the water supply pipe 11 and the hot water supply pipe 12 each have a length of 5 m and a heat insulating material having a thickness of 20 mm is wound around them. A solar hot water supply system having a structure was produced.

Then, the set temperature of the temperature sensor 27 for controlling the pump 23 is changed to start at 85 ° C. and stop at 80 ° C. to reduce the cooling capacity when circulating the pump,
Moreover, the hot water of 70 ° C. was supplied to the solar water heater 10 in the morning on a sunny day to create a situation in which the first hot pressure valve 24 was forcibly operated.

Under such conditions, if the hot water is not used at all during the day, the hot water temperature in the solar water heater 10 becomes 85 ° C. after about 2 hours, and the pump 23 is detected by the temperature sensor 27. It worked, but the hot water temperature gradually increased during circulation and
The temperature reached 0 ° C., the first warm pressure valve 24 was activated, and hot water was discharged through the drainage pipe. Then, the same amount of water as the discharged amount entered the solar water heater 10 from the water supply pipe 11 to lower the hot water temperature. The maximum temperature reached by the hot water in the solar water heater 10 on this day was about 90 ° C, and the amount of solar radiation was about 5060 kcal.
/ M ² · day.

(Example 3) In the solar hot water supply equipment having the same structure as in Example 1, the power of the pump 23 was turned off in case of power failure or failure of the pump 23, and left without using hot water at all during the day. Then, even when the hot water temperature in the solar water heater 10 reached 80 ° C., the pump 23 did not operate and the hot water temperature continued to rise.

Unless the hot water is circulated by the pump 23, the first hot pressure valve 24 cannot detect the hot water temperature in the solar water heater 10, so the hot water temperature is the set temperature of the first hot pressure valve 24. The first hot pressure valve 24 did not operate even at 90 ° C.

The temperature of the hot water in the solar water heater 10 is 95 ° C.
When it becomes, the second temperature and pressure valve 26 is activated, hot water is discharged along the roof through the drainage pipe, and the same amount of water as that discharged enters the solar water heater 10 from the water supply pipe 11, The water temperature was lowered. The maximum temperature reached by the hot water in the solar water heater 10 on this day was approximately 95 ° C, and the amount of solar radiation was approximately 4910 kc.
It was al / m ² · day.

(Embodiment 4) In a solar hot water supply facility having the same structure as in Embodiment 2, if the hot water is left unused during the daytime, the hot water temperature in the solar water heater 10 becomes 85 ° C. after about 2 hours. The temperature sensor 27 detects and the pump 23 operates. Approximately one hour after the pump 23 starts operating, the drainage valve 33 is opened to drain hot water assuming that hot water is used in a kitchen or the like, and the second flow rate switch 30 is activated to operate the pump 23. Stopped. The pump 23 remained stopped while the hot water was discharged. The highest temperature reached by the hot water in the solar water heater 10 on this day was about 90 ° C., and the amount of solar radiation was about 5060 kcal / m ² · day.

[0052]

As described above, when the solar hot water supply equipment of the present invention is used, the solar water heater is used at a pressure of 1 kg / cm ² or more, and even if it is left without hot water for two or more days in the summer fine weather. The hot water can be discharged to the outside by suppressing the rise of the hot water temperature by operating the pump to circulate the hot water or by operating the first hot pressure valve.

In addition, even if an abnormal situation such as a power failure or a pump failure occurs, the second hot pressure valve operates to discharge hot water to the outside, so that the hot water temperature in the solar water heater is increased. Is 1
Do not exceed 00 ° C.

Further, in the present invention, the first flow rate switch stops the pump when water does not circulate during operation of the pump, so that failure can be prevented and abnormality in circulation can be detected. Furthermore, when the hot water is used in the bath or the kitchen, the pump is stopped by the second flow rate switch, so that the decrease in the hot water supply amount can be prevented.

[Brief description of the drawings]

FIG. 1 is a system diagram showing a solar hot water supply system of the present invention.

FIG. 2 is a system diagram showing a conventional solar hot water supply facility.

[Explanation of symbols]

 10 solar water heater 11 water supply pipe 12 hot water supply pipe 13 pressure reducing valve 15 mixing valve 20 strainer 21 first communication pipe 22 second communication pipe 23 pump 24 first temperature and pressure valve 25 first flow rate switch 26 second temperature and pressure valve 27 Temperature Sensor 28 First Check Valve 29 Second Check Valve 30 Second Flow Switch 31 Third Check Valve 33 Drain Valve

Claims (5)

[Claims] 1. A solar water heater that uses solar heat to heat water, a water supply pipe for connecting to a water inlet of the solar water heater to supply water to the solar water heater, and a water outlet of the solar water heater. A solar hot water supply facility comprising a hot water supply pipe for taking out hot water from the solar water heater, wherein the water supply pipe is provided with a pressure reducing valve at a position lower than the solar water heater, and on the secondary side of the pressure reducing valve, and The first communication pipe that connects the water supply pipe and the hot water supply pipe at a position lower than the solar water heater is provided, and the mixing valve is provided at the connecting portion between the first communication pipe and the hot water supply pipe, so that the solar heat A second communication pipe that connects the water supply pipe and the hot water supply pipe is provided at a position lower than the solar water heater on the side of the water heater, and the second communication pipe has a pump, a first warm pressure valve, and a first flow rate. A switch is installed and a second flow switch is installed at the mixed water outlet of the mixing valve. A second hot pressure valve is provided at the outlet of the solar water heater, and a temperature sensor for detecting the hot water temperature of the solar water heater to control the operation of the pump is provided, and the set pressure of the pressure reducing valve is set to the first hot pressure valve and The set temperature of the second warm pressure valve is set lower than that of the first warm pressure valve, and the set pressure of the first warm pressure valve is set lower than that of the second warm pressure valve. The temperature is set lower than the set temperatures of the hot pressure valve and the second hot pressure valve, and the set temperature of the first hot pressure valve is set lower than the set temperature of the second hot pressure valve, and the first flow rate switch and the second flow rate are set. Solar hot water supply facility characterized by controlling the operation of the pump with a switch. 2. A connecting portion between the first communication pipe and the water supply pipe, and a second connecting pipe.
The water supply pipe between the connecting pipe and the water supply pipe is provided with the first check valve for allowing the flow from the pressure reducing valve to the solar water heater and preventing the flow in the opposite direction, and for the second communication. The second that allows the pipe to flow from the hot water supply pipe to the water supply pipe and prevents flow in the opposite direction
The check valve is provided, and a third check valve is provided in the hot water supply pipe near the outlet of the mixing valve to allow the flow of the mixed water in the direction of exit and prevent the flow in the opposite direction. The solar hot water supply equipment according to claim 1. 3. The solar hot water supply equipment according to claim 1, wherein a drainage valve is provided on the secondary side of the third check valve. 4. The solar hot water supply system according to claim 1, wherein a strainer is provided on the water supply pipe on the primary side of the pressure reducing valve. 5. The solar hot water supply equipment according to claim 1, wherein the set temperature of the temperature sensor for starting the pump is set to 70 ° C. or higher and 90 ° C. or lower.