JP2003042541A - Hot water supply system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hot water supply system in which abnormality only of a potable water system or a solar system can be detected surely and dealt with. SOLUTION: The hot water supply system comprises a hot water supply apparatus 30 as a main heat source, a heat storage tank 14 for storing hot water produced from a water heater 10 utilizing solar heat, and a hot water supply connection unit 20 mounting a mixing regulation valve 21 for delivering hot water of a target temperature to the hot water supply apparatus 30 by mixing potable water, as required, to hot water delivered from the heat storage tank 14, wherein the mixing regulation valve 21 delivers only hot water supplied from the heat storage tank 14 to the hot water supply apparatus 30 under full-open state, and delivers only potable water to the hot water supply apparatus 30 under full-close state. Based on the delivery hot water temperature when the mixing regulation valve 21 is hunting, the potable water temperature and the target water temperature, a decision is made whether an abnormality is present in the potable water system or the solar system or not, and the mixing regulation valve 21 is forcibly closed when a decision is made that an abnormality is present in the potable water system or the solar system.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention stores hot water generated by an auxiliary heat source such as solar heat in a heat storage tank,
The present invention relates to a hot water supply system in which hot water is delivered to a water heater via a hot water supply connection unit that can be mixed with tap water.

[0002]

2. Description of the Related Art As a hot water supply system using an auxiliary heat source, for example, a hot water supply system in which a solar water heater and a water heater are combined to generate hot water using solar heat has been generally known.

In such a hot water supply system, a solar water heater and a water heater having a heat storage tank for storing hot water generated by utilizing solar heat are connected via a hot water supply connection unit, At the time of hot water supply, the hot water stored in the heat storage tank of the solar water heater is delivered to the water heater via the hot water connection unit, but the hot water connection unit simply delivers the hot water stored in the heat storage tank to the water heater. Instead of using hot water sent from the heat storage tank as needed, tap water can be sent to the water heater in a state where the clean water is mixed with it. It is equipped with a mixing control valve that sends water to the water heater and sends only clean water to the water heater when fully closed.

Therefore, when hot water having a temperature higher than the hot water supply set temperature set for the water heater is stored in the heat storage tank, the mixing control valve of the hot water supply connection unit has a temperature higher than the hot water supply set temperature sent from the heat storage tank. By appropriately mixing hot water and tap water, hot water at the hot water supply set temperature that is the target temperature is generated,
This is sent to the water heater. On the other hand, when hot water having a temperature higher than the hot water supply set temperature is not stored in the heat storage tank, the mixing control valve of the hot water supply connection unit appropriately mixes hot water below the hot water supply set temperature sent from the heat storage tank with clean water. The hot water having the set temperature for hot water is generated by sending the hot water to the hot water supply device while forcibly lowering it to the fixed temperature which is the target temperature and burning the burner of the hot water supply device.

By the way, in such a hot water supply system, for example, a valve or the like that shuts off a pipe path connecting the heat storage tank and the hot water supply connection unit is left open, or the heat storage tank is emptied for some reason. , When the hot water supply operation is performed in a state where hot water cannot be delivered from the heat storage tank to the hot water supply connection unit at all, the mixing control valve opens to the fully open side in an attempt to generate hot water at the target temperature, but from the heat storage tank Since hot water is not supplied, the amount of hot water delivered to the water heater decreases, and falls below the minimum operating water amount of the water heater.

When the amount of hot water delivered to the water heater falls below the minimum operating water amount of the water heater in this way, it is recognized that the hot water supply has been stopped, and the mixing control valve is brought to the half-open state, which is the standby position when the hot water supply is stopped. Therefore, the clean water starts to be sent to the water heater again, and by repeating the same operation, the mixing control valve starts the hunting operation, and the normal hot water supply operation cannot be performed.

Therefore, in the conventional hot water supply system, when such a hunting operation of the mixing control valve occurs, it is determined that hot water cannot be supplied from the heat storage tank, and the mixing control valve is forced. By fully closing and sending only clean water to the water heater, a hot water supply operation that does not use the hot water stored in the heat storage tank is performed.

Depending on the structure of the hot water supply connection unit, hot water can be sent from the heat storage tank to the hot water supply connection unit, but in the case where tap water cannot be sent to the hot water supply connection unit due to water interruption or the like, There is a possibility of falling into the same state.In such a case, it is possible to forcibly stop the hot water supply operation by catching the hunting operation of the mixing control valve and forcibly closing the mixing control valve fully. To be

[0009]

However, in the hunting operation of the mixing control valve as described above, when hot water cannot be delivered from the heat storage tank to the hot water supply connection unit, or when hot water is supplied to the hot water supply connection unit due to water interruption or the like. Not only when it cannot be delivered, but a similar state may occur due to the operation of the curran, so the hunting operation of the mixing control valve is detected and the mixing control valve is forced to fully close. If this happens, even if the hot water supply system itself can operate normally, if the hunting operation of the mixing control valve occurs due to the operation of the current controller, etc., the heat storage tank will remain until the operating status is reset. There is a problem that the hot water supply operation cannot be performed by effectively utilizing the hot water stored in.

Therefore, an object of the present invention is to provide a hot water supply system capable of reliably detecting only the above-mentioned system abnormality and coping with it.

[0011]

In order to solve the above problems, the invention according to claim 1 provides a water heater as a main heat source, a heat storage tank for storing hot water generated by an auxiliary heat source, The hot water sent from the heat storage tank is provided with a hot water supply connection unit equipped with a hot water supply device having a target temperature by mixing hot water as needed to the hot water supply device, and the hot water supply connection unit, In a hot water supply system in which only the hot water sent from the heat storage tank is sent to the water heater when fully opened, and only the clean water is sent to the water heater when fully closed, the mixing control valve performs a hunting operation. Based on the temperature of hot water delivered from the hot water supply connection unit and the temperature of tap water when performing, it is determined whether or not hot water cannot be delivered from the heat storage tank to the hot water supply connection unit, The heat storage tank Al wherein when it is determined that the delivery a condition not hot water in the hot water supply connection unit, than it was to forcibly fully closed the mixing control valve.

As described above, in this hot water supply system, not only the hunting operation of the mixing control valve, but also the temperature of hot water sent from the hot water connection unit and the temperature of tap water when the mixing control valve is performing the hunting operation. Based on the above, it is determined whether or not hot water cannot be delivered from the heat storage tank to the hot water supply connection unit, so that only the hunting operation of the mixing control valve is caught and the mixing control valve is forced. Unlike the conventional hot water system, which is fully closed,
It becomes possible to identify the hunting operation of the mixing control valve based on the curran operation etc., and only when the hot water cannot be sent from the heat storage tank to the hot water supply connection unit, the hot water stored in the heat storage tank can be stored. It is possible to switch to hot water supply operation that is not used.

In a state where hot water cannot be delivered from the heat storage tank to the hot water supply connection unit, the temperature of the hot water delivered from the hot water supply connection unit during the hunting operation of the mixing control valve becomes the temperature of the tap water. Therefore, as in the hot water supply system according to the second aspect of the present invention, the temperature of the hot water delivered from the hot water supply connection unit when the mixing control valve is performing the hunting operation is a predetermined temperature added to the clean water temperature. When the temperature is equal to or lower than the determined reference temperature, it may be determined that hot water cannot be delivered from the heat storage tank to the hot water supply connection unit.

Particularly, as in the hot water supply system according to the third aspect of the present invention, the temperature of the hot water delivered from the hot water supply connection unit when the mixing control valve is performing the hunting operation is equal to the temperature of the clean water at a predetermined temperature. Even if the mixing control valve maintains the fully open state for a predetermined time or more even if the temperature is equal to or lower than the determination reference temperature obtained by adding the above, it is determined that hot water can be sent from the heat storage tank to the hot water supply connection unit. By doing so, even if the temperature of the hot water stored in the heat storage tank is close to the temperature of the tap water, it is possible to identify the hunting operation of the mixing control valve based on the curran operation, etc. The effect of improving accuracy is obtained.

After it is determined that hot water cannot be delivered from the heat storage tank to the hot water supply connection unit, and the mixing control valve is forcibly fully closed, the hot water supply system according to the fourth aspect of the present invention is provided. , When the operating state is reset by operating the operating switch of the water heater, or when a predetermined time elapses without resetting the operating state, the mixing control valve is returned to the normal control state. do it.

In order to solve the above-mentioned problems, the invention according to claim 5 is such that a water heater serving as a main heat source, a heat storage tank for storing hot water generated by an auxiliary heat source, and a heat storage tank for delivering hot water. A hot water supply connection unit equipped with a mixing control valve that sends hot water of a target temperature to the water heater by mixing hot water as necessary with hot water, and the mixing control valve is fully opened from the heat storage tank. In a hot water supply system in which only the hot water that is sent is sent to the water heater and only the clean water is sent to the water heater when fully closed, the hot water supply when the mixing control valve is performing a hunting operation. Based on the temperature of the hot water delivered from the connection unit and the target temperature, it is determined whether or not it is impossible to deliver the clean water to the hot water supply connection unit, and it is impossible to deliver the clean water to the hot water supply connection unit. Is If it is determined it is than it was to forcibly fully closed the mixing control valve.

As described above, in this hot water supply system, not only the hunting operation of the mixing control valve but also the temperature of the hot water delivered from the hot water supply connection unit when the mixing control valve is performing the hunting operation and the target temperature are controlled. Based on this, it is determined whether or not tap water cannot be delivered to the hot water supply connection unit, so that only the hunting operation of the mixing control valve is caught and the mixing control valve is forced to fully close. Unlike the conventional hot water supply system described above, it is possible to identify the hunting operation of the mixing control valve based on the curran operation, etc., and only when the hot water cannot be delivered to the hot water supply connection unit The operation can be stopped forcibly.

In a state where it is impossible to deliver clean water to the hot water supply connection unit, the temperature of the hot water delivered from the hot water supply connection unit while the mixing control valve is performing the hunting operation is delivered from the heat storage tank. Since the temperature of the hot water approaches the temperature of the hot water, the temperature of the hot water delivered from the heat storage tank is equal to or higher than the target temperature and the temperature of the hot water delivered from the hot water supply connection unit is the same as the hot water supply system according to the invention. When the temperature is equal to or higher than the determination reference temperature obtained by adding the predetermined temperature to the target temperature, it may be determined that the tap water cannot be delivered to the hot water supply connection unit.

Further, after it is determined that the tap water cannot be delivered to the hot water supply connection unit and the mixing control valve is forcibly fully closed, as in the hot water supply system of the invention according to claim 7,
It is desirable to return the mixing control valve to a normal control state only when the operation state is reset by operating the operation switch of the water heater.

In this case, it is determined that hot water cannot be delivered from the heat storage tank to the hot water supply connection unit, and unlike the case where the mixing control valve is forcibly fully closed, no hot water can be supplied. , In some cases, the hot water supply may be stopped with the currant open, and in such a case, if the mixing control valve is automatically returned to the normal control state after a lapse of a predetermined time, the heat is stored against the user's intention. This is because the hot water of high temperature stored in the tank may be discharged from the currant.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments will be described below with reference to the drawings. FIG. 1 shows a schematic configuration of a hot water supply system 1 using solar heat as an auxiliary heat source. As shown in FIG. 1, this hot water supply system 1 is a system in which a solar water heater 10 and a water heater 30 are connected via a hot water supply connection unit 20, and the hot water generated by the solar water heater 10 is used for hot water supply. Water heater 3 via connection unit 20
It is designed to be sent to 0.

The solar water heater 10 comprises a solar heat exchanger 11 and a closed heat storage tank 14, and the heat storage tank 14 has a water supply pipe 15 for supplying clean water to the lower end thereof. In addition to being connected, a hot water supply pipe 16 for sending the stored hot water to the hot water supply connection unit 20 is connected to the upper end portion.

In the solar heat exchanger 11, a circulation path for a heat medium is formed by a solar pipe 12 connecting the inlet side and the outlet side of the solar heat exchanger 11.
Has a heat exchange part 13 partially introduced into the heat storage tank 14. Therefore, the heat medium heated by the solar heat exchanger 11 passes through the solar pipe 12 and the heat storage tank 1
4 is introduced into the heat storage tank 14, and heat is exchanged with the water in the heat storage tank 14 by the heat exchange unit 13, whereby hot water is generated in the heat storage tank 14.

As shown in the figure, the hot water supply connection unit 20 supplies clean water supplied via a water supply pipe 22 and hot water supplied from the heat storage tank 14 via a hot water supply pipe 16.
A hot water pipe 23 is provided with a mixing control valve 21 that mixes as needed, and the hot water sent from the heat storage tank 14 is connected to the outlet side of the mixing control valve 21 as it is or in a state of being appropriately mixed with tap water. It is sent to the water heater 30 via the heat exchanger 31 and is supplied to the hot water heater 30 through the heat exchanger 31 of the water heater 30. In addition, the mixing control valve 21 is in a fully opened state, and the heat storage tank 14 is
From the hot water supply pipe 16, only hot water is sent to the water heater 30, and conversely, in the fully closed state, only clean water supplied via the water supply pipe 22 is sent to the water heater 30. Has become.

Further, the water supply pipe 22 and the hot water pipe 23 are connected to each other through a bypass pipe 24 in which a diaphragm type electromagnetic valve 25 which is fully closed when energized is installed.
The hot water supply pipe 16 and the hot water pipe 23 connected to the mixing control valve 21 include a hot water temperature sensor 26 for detecting a temperature (hereinafter referred to as hot water temperature) Ts of hot water sent from the heat storage tank 14, and a hot water supply connection. The temperature of hot water delivered to the unit 20 (hereinafter referred to as the tap water temperature) Tw and the temperature of the hot water sent from the hot water connection unit 20 (hereinafter referred to as the tap water temperature). A hot water temperature sensor 28 for detecting To is installed.

The hot water supply connection unit 20 and the hot water supply device 30
Are equipped with controllers 20a and 30a capable of communicating with each other via a serial interface, and the operation remote controller 40 of the water heater 30 communicates with the controller 30a of the water heater 30 via a serial interface. A possible controller 40a is mounted and these controllers 20a, 30a, 4
0a controls the operation of the hot water supply system 1 comprehensively while cooperating with each other.

Controller 20 of hot water supply connection unit 20
The temperature detection signals from the hot water temperature sensor 26, the clean water temperature sensor 27, and the hot water temperature sensor 28 are input to a, and the hot water supply set temperature Te and the operation switch signal set by the operation remote controller 40, the burner combustion signal, The controller 30a of the water heater 30 transmits a water flow signal or the like for detecting and turning on the water flow of the minimum operation water amount or more, and these temperature detection signals and the hot water supply set temperature Te.
Based on the controller 20 of the hot water supply connection unit 20
a controls the mixing control valve 21.

The temperature of the hot water delivered from the heat storage tank 14, that is, the hot water temperature T detected by the hot water temperature sensor 26.
When s is equal to or higher than the hot water supply set temperature Te, the hot water of the hot water supply set temperature Te can be supplied by appropriately mixing the clean water without burning the burner of the water heater 30. The temperature of the hot water delivered,
That is, the mixing control valve 21 is adjusted so that the hot water temperature To detected by the hot water temperature sensor 28 becomes the hot water supply set temperature Te.
The hot water supply set temperature control for controlling is performed.

On the other hand, when the hot water supply temperature Ts is lower than the hot water supply set temperature Te, hot water of the hot water supply set temperature Te cannot be supplied unless the burner of the hot water supply device 30 is burned, so the burner of the hot water supply device 30 is burned. By so doing, the hot water supply temperature Ts is not lower than 60 ° C. and lower than 60 ° C. so that the hot water having the hot water supply set temperature Te can be reliably generated.
Cases of 5 ° C or higher and lower than 35 ° C are divided into 45 ° C when the temperature is 60 ° C or higher, and 30 ° C when the temperature is lower than 60 ° C and 35 ° C or higher
When the temperature is lower than 0 ° C., the fixed temperature control for mixing the clean water is performed by adjusting the opening degree of the mixing control valve 21 so that the hot water having the fixed temperature Tf of 25 ° C. is delivered.

Further, the heat storage tank 14 and the hot water supply connection unit 20
A valve (not shown) or the like installed in the hot water supply pipe 16 that connects the heat storage tank 14 to the hot water supply connection unit 20 is omitted because the heat storage tank 14 is empty for some reason. When the hot water supply operation is performed in a state in which no hot water can be delivered at all, or in a state in which no clean water can be delivered to the hot water supply connection unit 20 due to water interruption, as described above, the mixing control valve 21 cannot perform a normal hot water supply operation by causing a hunting operation. Therefore, when such a system abnormality occurs, the controller 20a of the hot water supply connection unit 20 detects this and switches to an appropriate operation operation. Has become. Hereinafter, the abnormality detection when a system abnormality occurs and the driving operation at that time will be described in detail with reference to the flowcharts shown in FIGS. 2 and 3.

First, as shown in FIG. 2, after the counter N and the counter M are reset (step S1), it is judged whether or not a state where the OFF time of the water flow signal is within 2 seconds has occurred (step S2). . Here, when the state where the OFF time of the water flow signal is within 2 seconds does not occur, it is determined that the mixing control valve 21 is not performing the hunting operation, and the counter N is reset again (step S9), Control goes to step S2.

On the other hand, in step S2, when a state in which the OFF time of the water flow signal is within 2 seconds occurs, it is subsequently determined whether or not the tap water temperature To at that time is equal to or higher than the tap water temperature Tw + 5 ° C. (Step S3). If the tap water temperature To is equal to or higher than the tap water temperature Tw + 5 ° C., there is a possibility that an abnormality has occurred in the tap water system. Therefore, the tap water temperature To is further set to the target temperature (hot water supply set temperature Te or fixed temperature). Tf) It is determined whether or not the temperature exceeds Tt + 5 ° C (step S4). Here, when the hot water outlet temperature To is equal to or lower than the target temperature Tt + 5 ° C., it is determined that no abnormality has occurred in the water supply system, the counter N is reset again (step S9), and then the process proceeds to step S2.

In step S4, if the hot water outlet temperature To exceeds the target temperature Tt + 5 ° C., there is a possibility that an abnormality has occurred in the water supply system. Therefore, the water flow signal is turned off within 2 seconds. It is determined whether the time until the water flow signal is turned off after the occurrence of is less than 20 seconds (step S5). Here, when the ON time of the water flow signal continues for 20 seconds or more, it is determined that the mixing control valve 21 does not perform the hunting operation, and the counter N is reset again (step S9), and then the process proceeds to step S2. Transition.

On the other hand, in step S5, if the ON time of the water flow signal is less than 20 seconds, the mixing control valve 21 may be in the hunting operation. Therefore, after adding 1 to the counter N (step S5). S6), counter N
= 2 is determined (step S7). Here, when the counter N = 1, there is a high possibility that an abnormality has occurred in the water supply system, and therefore, the routine returns to step S2 and the same operation is repeated without resetting the counter N.

In step S7, when the counter N = 2, the OFF state of the water flow signal within 2 seconds occurs again after the OFF state of the water flow signal within 2 seconds occurs and before 20 seconds have elapsed. As it has been done, the mixing control valve 2
1 has caused a hunting operation, and moreover, the tap water temperature To at that time is higher than the target temperature Tt + 5 ° C., so that tap water cannot be delivered to the hot water supply connection unit 20 due to an abnormality in the tap water system, that is, due to water interruption or the like. (Step S8), the mixing control valve 21 is forcibly fully closed (step S16).

As a result, the delivery of hot water from the heat storage tank 14 to the hot water supply connection unit 20 is completely cut off. Therefore, when the clean water cannot actually be delivered to the hot water supply connection unit 20 due to water interruption or the like, the hot water supply is performed. The system 1 is in a state where hot water supply operation cannot be performed.

On the other hand, in step S3, the tap water temperature T
If o is lower than the tap water temperature Tw + 5 ° C., there is a possibility that an abnormality has occurred in the solar water heater system (hereinafter referred to as the solar system). It is determined whether it is less than 4 seconds (step S10). Here, when the mixing control valve 21 is fully opened for 4 seconds or more, it is determined that no abnormality has occurred in the solar system, the counter M is reset again (step S15), and the process proceeds to step S2. . In addition,
In step S10, it is determined whether or not the fully open time of the mixing control valve 21 is less than 4 seconds because the temperature of the hot water stored in the heat storage tank 14 is the clean water temperature Tw + 5.
If the temperature is below ℃, even if there is no abnormality in the solar system, the outlet hot water temperature To will be lower than the tap water temperature Tw + 5 ° C, so do not judge such operating conditions as an abnormality in the solar system. This is because.

In step S10, the mixing control valve 21
If the full open time is less than 4 seconds, there is a possibility that an abnormality has occurred in the solar system. Then, after the water flow signal is turned off within 2 seconds, the water flow signal is turned off next. It is determined whether or not the time taken to do so is less than 20 seconds (step S11). Here, when the ON time of the water flow signal continues for 20 seconds or more, it is determined that the mixing control valve 21 does not perform the hunting operation, and the counter M is reset again (step S15), and then step S15.
Move to 2.

On the other hand, in step S11, if the ON time of the water flow signal is less than 20 seconds, the mixing control valve 21
May cause a hunting operation, the counter M is incremented by 1 (step S12), and then it is determined whether or not the counter M = 2 (step S13).
Here, when the counter M = 1, there is a high possibility that an abnormality has occurred in the solar system, and therefore the procedure returns to step S2 and the same operation is repeated without resetting the counter M.

In step S13, the counter M = 2
In the case of, the water flow signal OFF state occurs within 2 seconds, and then the water flow signal OFF state within 2 seconds occurs again before 20 seconds have elapsed. Therefore, the mixing control valve 2
1 has caused a hunting operation, and since the hot water discharge temperature To at that time is below the clean water temperature Tw + 5 ° C., an abnormality in the solar system, that is, hot water is sent from the heat storage tank 14 to the hot water supply connection unit 20. Assuming that the mixing control valve 21 cannot be operated (step S14), the mixing control valve 21 is forcibly fully closed (step S16).

As a result, the delivery of hot water from the heat storage tank 14 to the hot water supply connection unit 20 is completely cut off, and only the clean water is delivered to the hot water supply connection unit 20, so the hunting operation of the mixing control valve 21 is performed. Is stopped, and the hot water supply operation that does not use the hot water stored in the heat storage tank 14 is switched to.

The operation of returning to the normal hot water supply operation state when the mixing control valve 21 is forcibly fully closed as described above will be described below. First, as shown in FIG.
When the user intentionally resets the operating state by turning the operating switch of the operation remote controller 40 of the water heater 30 on and off (step S21), the user intentionally resets the operating state. The forced fully closed state of the mixing control valve 21 is released to return to the normal control state (step S24).

In step S21, if the user does not intentionally reset the operating state, it is determined whether or not the factor that forcedly closes the mixing control valve 21 is due to an abnormality in the solar system. (Step S22),
When the mixing control valve 21 is forcibly fully closed based on an abnormality in the water supply system, the process returns to step S21, and the mixing control valve 21 is normally closed only when the user intentionally resets the operating state. Return to the control state (step S2)
4).

On the other hand, in step S22, if the mixing control valve 21 is forcibly fully closed based on an abnormality of the solar system, then, for 4 hours from the time when the mixing control valve 21 is forcibly fully closed. It is determined whether or not has passed (step S23). Here, when 4 hours have not elapsed, the process returns to step S21, and the mixing control valve 21 is returned to the normal control state only when the user intentionally resets the operating state (step S24). When 4 hours have elapsed, the mixing control valve 21 is automatically returned to the normal control state (step S24).

Even when the mixing control valve 21 is returned to the normal control state in this manner, the clean water which is a factor that forcedly closes the mixing control valve 21. Unless the system abnormality or the solar system abnormality is resolved, the same operation is repeated again.

If there is an abnormality in the solar system,
As described above, even if the mixing control valve 21 is fully closed, tap water is sent to the hot water supply connection unit 20 so that hot water can be supplied, but if there is an abnormality in the clean water system, hot water cannot be supplied at all. In this case, the hot water supply may be stopped with the cullan open. In such a case, if the mixing control valve 21 is automatically returned to the normal control state after a lapse of a predetermined time, the user's There is a possibility that the hot water of high temperature stored in the heat storage tank may be discharged from the currant against the intention, so that the mixing control valve 21 is returned to the normal control state only when the user intentionally resets the operating state. I am trying.

As described above, in this hot water supply system 1,
Not only the hunting operation of the mixing control valve 21, but also the tap water temperature T when the mixing control valve 21 is performing the hunting operation.
Since it is determined whether or not there is an abnormality in the clean water system or the solar system based on o, the clean water temperature Tw, and the target temperature Tt, the hunting operation of the mixing control valve 21 based on the curran operation or the like is surely performed. The mixing control valve 21 can be forcibly fully closed only when an abnormality occurs in the water supply system or the solar system.

In the above-described embodiment, the abnormality detection of the water supply system and the abnormality detection of the solar system are performed at the same time. However, the present invention is not limited to this, and any one abnormality is detected. It is also possible to forcefully close the mixing control valve 21.

Further, in the above-mentioned embodiment, when the OFF state of the water flow signal within 2 seconds occurs again 20 seconds after the OFF state of the water flow signal occurs within 2 seconds, Although it is determined that the mixing control valve 21 is causing the hunting operation, the present invention is not limited to this, and the water flow signal OFF time, the water flow signal OFF interval, the water flow signal OFF count, etc. are actually mixed. It may be appropriately set in consideration of the situation when the control valve 21 is causing the hunting operation.

Further, in the above-described embodiment, the water temperature T
Although a temperature obtained by adding “5 ° C.” to w or the target temperature Tt is adopted as the determination reference temperature, the temperature is not limited to this, and the temperature to be added to the water temperature Tw or the target temperature Tt is mixed and adjusted. It may be set as appropriate in consideration of the fluctuation situation of the hot water outlet temperature To when the valve 21 is in the hunting operation.

Further, in the above-described embodiment, when the fully open state of the mixing control valve 21 continues for 4 seconds or more, it is determined that no abnormality has occurred in the solar system.
The duration time of the fully open state of the mixing control valve 21 serving as the determination standard is not limited to “4 seconds”, and the mixing control valve 21 when the temperature of the hot water stored in the heat storage tank 14 is close to the clean water temperature Tw. It may be set as appropriate in consideration of the driving status of.

Further, in the above-described embodiment, the duration of the fully closed state of the mixing control valve 21 is not considered when determining the abnormality of the water supply system. However, for example, the water supply temperature Tw is higher than the target temperature Tt. Mixing control valve 2 if it can increase
It may be determined that there is an abnormality in the water supply system when the duration of the fully closed state 1 is less than the predetermined time.

Further, in the above-mentioned embodiment, when the mixing control valve 21 is forcibly fully closed based on the abnormality of the solar system, it automatically returns to the normal control state after 4 hours have passed. However, the time period for automatically returning the mixing control valve 21 to the normal control state may be set appropriately in consideration of the usability of the hot water supply system 1, and the water supply system is not limited to this. Similarly to the case where the abnormality occurs in the above, the mixing control valve 21 may be returned to the normal control state only when the user intentionally resets the operation state.

The above-described embodiment is a hot water supply system using the solar water heater as an auxiliary heat source.
The auxiliary heat source in the hot water supply system is not limited to such a solar water heater, and various auxiliary heat sources such as a hot water supply system using waste heat of a gas engine or a gas turbine in a cogeneration system as an auxiliary heat source can be used. It goes without saying that the present invention can be applied to a hot water supply system using an auxiliary heat source.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment of a hot water supply system according to the present invention.

FIG. 2 is a flowchart showing an operation operation when a system abnormality occurs in the hot water supply system of the above.

FIG. 3 is a flowchart showing a driving operation when a system abnormality occurs in the hot water supply system of the above.

[Explanation of symbols]

1 Hot water supply system 10 Solar water heater 14 Heat storage tank 16 Hot water supply pipe 20 Hot water supply connection unit 20a controller 21 Mixing control valve 23 Hot water piping 26 Hot water temperature sensor 27 Water temperature sensor 28 Hot water temperature sensor 30 water heater 30a controller 31 heat exchanger 40 Operation remote control 40a controller

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Tetsuya Watanabe             93 Edo-cho, Chuo-ku, Kobe-shi, Hyogo Stock Association             Company Noritsu (72) Inventor Yoshihiko Tanaka             93 Edo-cho, Chuo-ku, Kobe-shi, Hyogo Stock Association             Company Noritsu

Claims (7)

[Claims] 1. A water heater serving as a main heat source, a heat storage tank for storing hot water generated by an auxiliary heat source, and hot water sent from the heat storage tank mixed with clean water as needed to obtain a target temperature. A hot water supply connection unit equipped with a mixing control valve for sending hot water to the hot water supply device, wherein the mixing control valve sends only the hot water sent from the heat storage tank to the hot water supply device when fully opened, and fully closed. In a hot water supply system adapted to deliver only clean water to the water heater, the temperature of hot water sent from the hot water supply connection unit and the temperature of the clean water when the mixing control valve is performing a hunting operation are set. Based on, it is determined whether or not hot water cannot be delivered from the heat storage tank to the hot water supply connection unit, and when it is determined that hot water cannot be delivered from the heat storage tank to the hot water supply connection unit, The above Hot water supply system is characterized in that so as to forcibly fully closed the case regulating valve. 2. When the temperature of the hot water delivered from the hot water supply connection unit when the mixing control valve is performing a hunting operation is equal to or lower than a determination reference temperature obtained by adding a predetermined temperature to the clean water temperature, The hot water supply system according to claim 1, wherein it is determined that hot water cannot be delivered from the heat storage tank to the hot water supply connection unit. 3. Even if the temperature of the hot water delivered from the hot water supply connection unit when the mixing control valve is performing a hunting operation is equal to or lower than a judgment reference temperature obtained by adding a predetermined temperature to the clean water temperature, The hot water supply system according to claim 2, wherein it is determined that hot water can be delivered from the heat storage tank to the hot water supply connection unit when the mixing control valve is kept fully open for a predetermined time or more. 4. After forcibly fully closing the mixing control valve, the operating state is reset by operating the operating switch of the water heater, or a predetermined time without resetting the operating state. The hot water supply system according to claim 1, 2 or 3, wherein the mixing control valve is returned to a normal control state when a certain time has elapsed. 5. A hot water supply device as a main heat source, a heat storage tank for storing hot water generated by an auxiliary heat source, and hot water sent from the heat storage tank, if necessary, are mixed with clean water to obtain a target temperature. A hot water supply connection unit equipped with a mixing control valve for sending hot water to the hot water supply device, wherein the mixing control valve sends only the hot water sent from the heat storage tank to the hot water supply device when fully opened, and fully closed. In a hot water supply system configured to deliver only clean water to the hot water supply device, based on a temperature of hot water delivered from the hot water supply connection unit and a target temperature when the mixing control valve is performing a hunting operation. , It is determined whether or not it is impossible to deliver the clean water to the hot water supply connection unit, and if it is determined that the clean water cannot be delivered to the hot water supply connection unit, the mixing control valve is forced Fully closed Hot water supply system, characterized in that there was Unishi. 6. The temperature of the hot water delivered from the heat storage tank is equal to or higher than a target temperature, and the temperature of the hot water delivered from the hot water supply connection unit is equal to or higher than a determination reference temperature obtained by adding a predetermined temperature to the target temperature. The hot water supply system according to claim 5, wherein it is determined that the tap water cannot be delivered to the hot water supply connection unit. 7. After the mixing control valve is forced to be fully closed, the mixing control valve is set to a normal control state only when the operation state is reset by operating the operation switch of the water heater. The hot water supply system according to claim 5 or 6, wherein the hot water supply system is returned to.