Storage hot water supply system

Abstract

To provide a storage hot water supply system capable of appropriately setting a circulation hot water storage heat quantity.SOLUTION: A storage hot water supply system (1) includes: a hot water storage unit (21) having a hot water storage tank (22) for storing hot water; a heat source machine (20) that performs a hot water storage operation for heating hot water in the hot water storage tank and returning the hot water to the hot water storage tank; and control means (10) for controlling the hot water storage operation. When hot water supply is not used, an instantaneous hot water circulation operation for causing hot water delivered from the hot water storage unit to flow in an instantaneous hot water circulation circuit (2) and returning the hot water to the hot water storage tank is performed. The control means is configured to learn and store a circulation heat quantity record of the instantaneous hot water circulation operation for a predetermined period and calculate a circulation hot water storage heat quantity for hot water storage in the hot water storage tank for a next predetermined period on the basis of the circulation heat quantity record.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a hot water storage and supply system that performs an instant hot water circulation operation of circulating heated hot water so that hot water can be supplied immediately from a hot water faucet or the like.

Background Art

[0002] Conventionally, a hot water supply device that heats raw water and adjusts the temperature to supply hot water has been widely used. At the start of hot water supply, since cold hot water remaining between the hot water supply device and the hot water faucet that uses the hot water flows out, it takes time until the hot water whose temperature has been adjusted by the hot water supply device is supplied, which is inconvenient.

[0003] Therefore, for example, as in Patent Document 1, there is known a hot water supply device provided with an instant hot water unit that drains the hot water remaining in the hot water supply passage and replenishes the hot water supply passage with the temperature-adjusted hot water. This instant hot water unit learns the heat dissipation characteristics of the hot water supply passage based on the outside air temperature in order to drain the hot water in the hot water supply passage whose temperature has decreased due to heat dissipation, and is configured to prohibit draining during a period when draining is not necessary set based on the outside air temperature and the heat dissipation characteristics.

[0004] However, draining the hot water remaining in the water supply passage without using it wastes water resources and also wastes the energy used for heating. Therefore, for example, in a bath facility or the like, a hot water supply system that performs an instant hot water circulation operation of circulating the hot water heated by a combustion-type hot water supply device so that the heated hot water is immediately supplied when the hot water faucet is opened is used. For example, Patent Document 2 describes a hot water supply device that learns the actual circulation flow rate of an instant hot water circulation operation performed by driving a circulation pump to calculate a determination value, and determines that hot water is being used when the circulation flow rate exceeds the determination value and stops the circulation pump.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] Due to the recent soaring energy prices, energy conservation is also required in a hot water supply system that performs an instant hot water circulation operation. The hot water supply device of Patent Document 2 heats the hot water that has returned to the hot water supply device in order to maintain the temperature of the hot water circulating in the instant hot water circulation operation. Since the temperature of the returned hot water is sufficiently higher than that of the city water, the instant hot water circulation operation is performed with a reduced heating capacity, but this operation efficiency is not high.

[0007] Therefore, a stored hot water supply system has been proposed in which hot water heated by a heat pump type heat source machine with excellent operation efficiency is stored in a hot water storage tank, and the stored hot water is circulated in an instant hot water circulation operation. In this stored hot water supply system, among the amount of heat stored in the hot water storage tank, the amount of stored heat for circulation for the instant hot water circulation operation is set in advance, and when the amount of heat stored decreases due to the discharge of hot water from the hot water storage tank due to hot water supply use, the discharge of hot water is restricted in order to secure the amount of stored heat for circulation.

[0008] However, the stored hot water supply system is affected by its operating environment, and the amount of heat required for instant hot water circulation varies depending on the ratio of instant hot water circulation to hot water supply use during a predetermined period of the installed facility. Therefore, it is not easy to set an appropriate amount of stored heat for circulation. For example, in winter when the temperature is low, the decrease in the amount of stored heat for circulation due to the heat dissipation of the circulating hot water and the hot water storage tank becomes large, so there is a risk that the amount of stored heat for circulation will be insufficient and the temperature of the circulating hot water cannot be maintained. On the other hand, when an excessive amount of stored heat for circulation is set, there is a risk that the discharge of hot water will be restricted even though there is heat available in the hot water storage tank for hot water supply.

[0009] Therefore, an object of the present invention is to provide a stored hot water supply system capable of appropriately setting the amount of stored heat for circulation.

Means for Solving the Problems

[0010] The hot water storage and supply system of the invention according to claim 1 includes a hot water storage unit having a hot water storage tank for storing hot and cold water, a heat source machine for performing a hot water storage operation of heating the hot and cold water in the hot water storage tank and returning it to the hot water storage tank, and a control means for controlling the hot water storage operation. In the hot water storage and supply system that performs an immediate hot water circulation operation of circulating the hot and cold water discharged from the hot water storage unit through an immediate hot water circulation passage and returning it to the hot water storage tank when there is no hot water supply use, the control means learns and stores the actual heat quantity of the immediate hot water circulation operation in a predetermined period, and calculates the hot water quantity for circulation hot water storage in the hot water storage tank for the next predetermined period based on the actual heat quantity of the circulation. It is characterized by this.

[0011] According to the above configuration, based on the actual heat quantity of the immediate hot water circulation operation in the learned and stored predetermined period, that is, the actually circulated heat quantity, the hot water quantity for circulation hot water storage required in the next predetermined period is calculated. Therefore, the actual heat quantity of the circulation according to the hot water supply use can be reflected in the hot water quantity for circulation hot water storage in the next predetermined period, and the hot water quantity for circulation hot water storage can be appropriately set.

[0012] The hot water storage and supply system of the invention according to claim 2, in the invention according to claim 1, has a water supply passage for supplying water to the hot water storage tank and water supply temperature detection means for detecting the water supply temperature of the water supply passage. When the control means determines that it is winter based on the water supply temperature, it calculates the hot water quantity for circulation hot water storage so as to compensate for the decrease in the heat quantity due to heat dissipation from the hot water storage tank. It is characterized by this. According to the above configuration, when it is determined that it is winter based on the water supply temperature, since the heat dissipation amount from the hot water storage tank increases, the hot water quantity for circulation hot water storage is calculated in consideration of the decreasing heat quantity. Therefore, the hot water quantity for circulation hot water storage can be appropriately set in consideration of the season.

[0013] The hot water storage and supply system of the invention according to claim 3, in the invention according to claim 1 or 2, has a plurality of hot water storage and supply devices each having the hot water storage unit and the heat source machine. When supplying hot water, hot water is discharged from the plurality of hot water storage and supply devices to the immediate hot water circulation passage, and the immediate hot water circulation operation is configured to be performed by a preset one hot water storage and supply device. It is characterized by this. According to the above configuration, the hot water stored in the hot water storage tanks of a plurality of hot water storage and supply devices can be used for hot water supply. Therefore, it is possible to cope with a large amount of hot water supply.

Effect of the Invention

[0014] According to the hot water storage and supply system of the present invention, the amount of heat for hot water circulation can be appropriately set.

Brief Description of the Drawings

[0015]

Figure 1

Figure 2

Figure 3

Modes for Carrying Out the Invention

[0016] Hereinafter, modes for carrying out the present invention will be described based on embodiments.

Embodiment

[0017] First, the configuration of the hot water storage and supply system 1 will be described with reference to FIG. 1. The hot water storage and supply system 1 is configured to be able to supply hot water from one or more hot water storage and supply devices to the instant hot water circulation passage 2 when using hot water. The instant hot water circulation passage 2 is formed by a hot water supply pipe 3 to which a plurality of mixing faucets F1 to Fn are connected and a hot water return pipe 4 on the downstream side thereof. The hot water return pipe 4 is provided with an air vent valve 5, and the air vent valve 5 discharges the air mixed in the hot water outside the instant hot water circulation passage 2.

[0018] The water supply pipe 6 for supplying raw water is connected to a plurality of mixing faucets F1 to Fn and a plurality (here, four) of storage water heaters so as to supply raw water (low-temperature water) as indicated by the arrow W. The plurality of mixing faucets F1 to Fn can supply hot and cold water obtained by mixing high-temperature water from the hot water supply pipe 3 and low-temperature water from the water supply pipe 6 and adjusted to a desired temperature. Incidentally, a water supply pipe of a system different from the plurality of storage water heaters may be connected to the plurality of mixing faucets F1 to Fn.

[0019] The hot water return pipe 4 is connected to one of the plurality of storage water heaters that is preset. The storage water heater to which the hot water return pipe 4 is connected is defined as the first hot water supply device 11, and the other storage water heaters are defined as the second, third, and fourth hot water supply devices 12, 13, and 14. The storage water heating system 1 performs an instant hot water circulation operation in which the first hot water supply device 11 circulates hot and cold water through the instant hot water circulation passage 2, and the first to fourth hot water supply devices 11 to 14 perform a hot water supply operation of supplying hot and cold water for hot water supply to the hot water supply pipe 3. This storage water heating system 1 has a system control unit 10 (control means) that controls the instant hot water circulation operation by the first hot water supply device 11 and the hot water supply operation by the first to fourth hot water supply devices 11 to 14.

[0020] Next, the first hot water supply device 11 will be described with reference to FIG. 2. The first hot water supply device 11 includes a hot water storage unit 21 having a hot water storage tank 22 and a heat pump type heat source machine 20 that stores heated hot and cold water in the hot water storage tank 22. A hot water supply passage 24 equipped with a hot water storage pump 23 is connected to the lower part of the hot water storage tank 22 to supply the hot water in the hot water storage tank 22 to the heat source machine 20. A hot water return passage 25 for returning the hot and cold water heated by the heat source machine 20 to the hot water storage tank 22 is connected to the upper part of the hot water storage tank 22.

[0021] At the bottom of the hot water storage tank 22, a water supply passage 26 for supplying make-up water from the water supply pipe 6 is connected. At the top of the hot water storage tank 22, a hot water discharge passage 27 for discharging the hot water in the hot water storage tank 22 from the hot water storage unit 21 is connected. A mixing valve 28 is disposed in the middle of the hot water discharge passage 27, and a water supply branch passage 29 branched from the middle of the water supply passage 26 is connected to the mixing valve 28. Then, the hot water from the hot water storage tank 22 and the make-up water from the water supply branch passage 29 are mixed by the mixing valve 28 and discharged from the hot water storage unit 21.

[0022] A plurality of hot water storage temperature sensors 22a to 22d are arranged in the hot water storage tank 22 at predetermined intervals in the height direction, and can detect the temperature of the hot water stored in the hot water storage tank 22 (hot water storage temperature) and the stored amount of the hot water at that temperature, that is, the stored heat quantity. And in order to prevent the stored hot water from cooling down, these hot water storage temperature sensors 22a to 22d and a heat insulating material (not shown) covering the hot water storage tank 22 are arranged.

[0023] In the water supply passage 26, an on-off valve 30 for opening and closing the water supply passage 26, a water supply temperature sensor 31 (water supply temperature detection means) for detecting the temperature of the make-up water flowing through the water supply passage 26 (water supply temperature), and a water supply flow sensor 32 for detecting the flow rate of the make-up water (water supply flow rate) are arranged.

[0024] In the hot water discharge passage 27, a tank hot water discharge temperature sensor 33, a hot water storage unit hot water discharge temperature sensor 34, and a hot water storage unit hot water discharge flow sensor 35 are arranged. The tank hot water discharge temperature sensor 33 detects the temperature of the hot water supplied from the hot water storage tank 22 to the mixing valve 28 (tank hot water discharge temperature). The hot water storage unit hot water discharge temperature sensor 34 detects the temperature of the hot water discharged from the hot water storage unit 21 (hot water storage unit hot water discharge temperature). The hot water storage unit hot water discharge flow sensor 35 detects the hot water discharge flow rate from the hot water storage unit 21. The downstream end of the hot water discharge passage 27 is connected to the hot water supply pipe 3 of the instant hot water circulation passage 2.

[0025] In the middle part of the hot water storage tank 22, a circulation return passage 36 for returning the hot water from the hot water supply return pipe 4 to the hot water storage tank 22 in the instant hot water circulation operation is connected below the hot water storage temperature sensor 22a at the uppermost stage of the hot water storage tank 22. In the circulation return passage 36, a circulation return temperature sensor 37 for detecting the temperature of the hot water flowing through the circulation return passage 36, a circulation return flow sensor 38 for detecting the flow rate of the circulation return passage 36, and an instant hot water circulation pump 39 for allowing the hot water to flow into the instant hot water circulation passage 2 are arranged. The circulation return passage 36 branches off a circulation return branch passage 36a on the downstream side of the instant hot water circulation pump 39 and is connected to the water supply branch passage 29, and a part of the hot water flowing through the circulation return passage 36 is mixed with the hot water from the hot water storage tank 22 by the mixing valve 28 and discharged as hot water. The flow rate of this circulation return branch passage 36a is adjusted by the mixing valve 28. Although not shown, the water supply passage 26, the circulation return passage 36, etc. are equipped with backflow prevention valves.

[0026] The hot water storage unit 21 has a hot water storage unit control unit 40 that controls the temperature adjustment of the hot water discharged from the hot water storage unit 21. This hot water storage unit control unit 40 performs hot water storage operation, instant hot water circulation operation, hot water supply operation, etc. of the first hot water supply device 11 based on a command from the system control unit 10 connected by communication.

[0027] In the hot water storage operation, the heat source machine 20 and the hot water storage pump 23 are driven to store the hot water heated to the hot water storage set temperature by the heat source machine 20 from the upper part of the hot water storage tank 22. The amount of heat stored in the hot water storage tank 22 is calculated by the hot water storage unit control unit 40 based on the detected temperatures of the hot water storage temperature sensors 22a to 22d, for example. The second, third, and fourth hot water supply devices 12, 13, and 14 have the same configuration as the first hot water supply device 11 except that they do not have the circulation return passage 36 having the instant hot water circulation pump 39, etc., and the description thereof is omitted.

[0028] The system control unit 10 performs an instant hot water circulation operation by the first hot water supply device 11 during a predetermined period (for example, the business hours of a facility where hot water supply is used) set as the period during which hot water supply is possible. During this instant hot water circulation operation, the on-off valves 30 of the second to fourth hot water supply devices 12 to 14 are closed, and it is possible to detect the use of hot water supply from the mixing faucet F1, etc. due to an increase in the water supply flow rate of the first hot water supply device 11.

[0029] When hot water supply use is detected, the instant hot water circulation operation is stopped and the hot water supply operation is performed. In the hot water supply operation, for example, hot water is discharged from the hot water storage and supply device selected by the system control unit 10 according to the hot water discharge flow rate and the stored hot water heat quantity of the first to fourth hot water supply devices 11 to 14. Incidentally, in the instant hot water circulation operation and the hot water supply operation, it is set such that hot water adjusted to the same temperature (for example, 50°C) is discharged from the first to fourth hot water supply devices 11 to 14.

[0030] In order to prevent the stored hot water heat quantity from being insufficient during a predetermined period, the system control unit 10 calculates the stored hot water heat quantity for circulation of the instant hot water circulation operation and calculates the stored hot water heat quantity for hot water supply, and adds these together to calculate the required heat quantity. The stored hot water heat quantity for circulation is calculated based on the actual heat quantity of circulation (the hot water discharge temperature of the hot water storage unit, the flow rate of the circulation return passage 36, and the circulation time) during a predetermined period learned and stored by the system control unit 10 in the past instant hot water circulation operation of the first hot water supply device 11.

[0031] Next, the hot water storage operation of the hot water storage and supply system 1 that stores the required heat quantity will be described based on the hot water storage operation flowchart of FIG. 3. Si (i = 1, 2,...) in the figure represents a step. When the hot water storage operation is started, first, in S1, it is determined whether it is currently other than winter based on the water supply temperature of the first hot water supply device 11. Winter is a step of determining whether to consider this heat dissipation because the heat dissipation amount from the instant hot water circulation passage 2 and the hot water storage tank 22 is larger than that in other than winter. For example, when the water supply temperature is 5°C or higher, it is determined that it is other than winter.

[0032] If the determination in S1 is Yes, proceed to S2. In S2, calculate the heat quantity of the stored hot water for circulation based on the actual heat quantity of the circulation, and proceed to S4. On the other hand, if the determination in S1 is No, proceed to S3. In S3, add the heat reduction (heat dissipation) due to heat dissipation from the hot water storage tank 22 to the heat quantity of the stored hot water for circulation calculated based on the actual heat quantity of the circulation to calculate the heat quantity of the stored hot water for circulation, and proceed to S4. The heat dissipation from the hot water storage tank 22 is calculated based on the relationship between the change in the feed water temperature and the hot water temperature learned and memorized during the hot water circulation operation. The hot water temperature T(t) [°C] after t seconds from the start of a predetermined period considering heat dissipation is expressed by the following formula (1), where the hot water temperature of the heat quantity of the stored hot water for circulation calculated based on the actual heat quantity of the circulation is T0, the feed water temperature is Tw, and the constant determined by the physical property values and the specifications of the hot water storage tank 22 is α. T(t)=(T0 - Tw)exp(-αt)+Tw ···(1)

[0033] Next, in S4, calculate the heat quantity of the stored hot water for hot water supply, and proceed to S5. The heat quantity of the stored hot water for hot water supply is calculated based on the hot water flow rate from the hot water storage unit 21 during hot water supply use in a predetermined period of the learned and memorized first to fourth hot water supply devices 11 to 14, the hot water outlet temperature of the hot water storage unit, and the time of hot water supply use, that is, based on the actual hot water supply performance. Then, in S5, calculate the necessary heat quantity for storing hot water for the instant hot water circulation operation and the hot water supply operation in a predetermined period, and proceed to S6.

[0034] The calculated necessary heat quantity is evenly distributed to the first to fourth hot water supply devices 11 to 14. The heat quantity of the stored hot water for circulation is set only for the first hot water supply device 11, and the heat quantity of the stored hot water for hot water supply of the first hot water supply device 11 is set to be smaller than that of the second to fourth hot water supply devices 12 to 14. The heat quantity of the stored hot water for circulation of the second to fourth hot water supply devices 12 to 14 is zero. In addition, when the first hot water supply device 11 is set to perform only the instant hot water circulation operation, only the heat quantity of the stored hot water for circulation is set for the first hot water supply device 11, and the heat quantity of the stored hot water for hot water supply is evenly distributed to the other second to fourth hot water supply devices 12 to 14.

[0035] Next, in S6, hot water storage is started and the process proceeds to S7, where it is determined whether the hot water storage of the required calorific value is completed. This is a step of determining whether the hot water storage of the calorific value distributed in the first to fourth hot water supply devices 11 to 14 is completed. While the determination in hot water storage S7 is No, hot water storage is continuously performed in the hot water supply device where hot water storage is not completed, and when the determination in S7 is Yes, the hot water storage operation is terminated. The hot water storage set temperature is set higher than the temperature of the hot water circulated in the instant hot water circulation operation according to the distributed calorific value.

[0036] The system control unit 10 starts the instant hot water circulation operation by the first hot water supply device 11 at the start of a predetermined period. When detecting hot water supply use based on an increase in the water supply flow rate, the instant hot water circulation operation is stopped, and the on-off valve 30 of the hot water supply device selected based on the water supply flow rate and the hot water storage calorific value is opened to discharge hot water. When the hot water storage calorific value of the hot water supply device discharging hot water runs out, the on-off valve 30 of this hot water supply device is closed, a hot water supply device with remaining hot water storage calorific value is selected, and its on-off valve 30 is opened to discharge hot water.

[0037] When the water supply flow rate of the hot water supply device that was discharging hot water decreases to zero, it is detected as the end of hot water supply use. When there is hot water storage calorific value for hot water supply in the first hot water supply device 11, its on-off valve 30 is opened to resume the instant hot water circulation operation, and the on-off valves 30 of the second to fourth hot water supply devices 12 to 14 are closed in preparation for the next hot water supply use. When there is no hot water storage calorific value for hot water supply in the first hot water supply device 11, the first hot water supply device 11 resumes the instant hot water circulation operation with the on-off valve 30 closed, and the on-off valve 30 of one hot water supply device with hot water storage calorific value other than the first hot water supply device 11 is opened to detect hot water supply use in preparation for the next hot water supply use.

[0038] The operation and effects of the above hot water storage and supply system 1 will be described. When there is no hot water supply demand, the hot water storage and supply system 1 performs an instant hot water circulation operation in which the hot water discharged from the hot water storage unit 21 is circulated through the instant hot water circulation passage 2 and returned to the hot water storage tank 22. The system control unit 10 (control means) learns and stores the actual heat quantity of the instant hot water circulation operation during a predetermined period, and calculates the hot water quantity for circulation storage in the hot water storage tank 22 based on this actual heat quantity of circulation. Since the hot water quantity for circulation storage is calculated based on the actual heat quantity of circulation, the actual heat quantity of circulation corresponding to the hot water supply demand can be reflected in the hot water quantity for circulation storage in the next predetermined period, and the hot water quantity for circulation storage can be appropriately set.

[0039] When the system control unit 10 determines that it is winter based on the water supply temperature, it calculates the hot water quantity for circulation storage so as to compensate for the decrease in the heat quantity due to heat dissipation during the instant hot water circulation operation. Since the heat dissipation amount is large in winter, by calculating the hot water quantity for circulation storage taking into account the heat quantity decreased due to heat dissipation, the hot water quantity for circulation storage can be appropriately set considering the season.

[0040] The hot water storage and supply system 1 has first to fourth hot water supply devices 11 to 14 each provided with a hot water storage unit 21 and a heat source machine 20. When supplying hot water, hot water is discharged from the first to fourth hot water supply devices 11 to 14 into the instant hot water circulation passage 2, and the instant hot water circulation operation is configured to be performed by one of the preset first hot water supply devices 11. Since the hot water stored in the hot water storage tanks 22 of the first to fourth hot water supply devices 11 to 14 can be used for hot water supply, it is possible to cope with a large hot water supply amount.

[0041] For example, the hot water storage unit control unit 40 of the first hot water supply device 11 may also be used as the system control unit 10 to control the hot water storage and supply system 1. The number of hot water storage and supply devices constituting the hot water storage and supply system 1 is not limited to the above, and it may be only one first hot water supply device 11. The hot water storage and supply system 1 may be provided with, for example, a combustion type auxiliary heat source machine so as to be able to supply hot water even when the stored hot water runs out.

[0042] In addition, those skilled in the art can implement the above-described embodiments in various modified forms without departing from the spirit of the present invention, and the present invention encompasses such modified forms.

Explanation of Reference Numerals

[0043] 1: Hot water storage and supply system 2: Instant hot water circulation passage 3: Hot water supply pipe 4: Hot water return pipe 5: Air release valve 6: Water supply pipe 10: System control unit (control means) 11 - 14: First - fourth hot water supply devices 20: Heat source machine 21: Hot water storage unit 22: Hot water storage tank 23: Hot water storage pump 24: Hot water storage forward passage 25: Hot water storage return passage 26: Water supply passage 27: Hot water outlet passage 28: Mixing valve 29: Water supply branch passage 30: On - off valve 31: Water supply temperature sensor (water supply temperature detection means) 32: Water supply flow sensor 33: Tank hot water outlet temperature sensor 34: Hot water storage unit hot water outlet temperature sensor 35: Hot water storage unit hot water outlet flow sensor 36: Circulation return passage 37: Circulation return temperature sensor 38: Circulation return flow sensor 39: Instant hot water circulation pump 40: Hot water storage unit control unit

Claims

1. A hot water storage supply system comprising a hot water storage unit having a hot water storage tank for storing hot water, a heat source machine for performing a hot water storage operation of heating the hot water in the hot water storage tank and returning it to the hot water storage tank, and control means for controlling the hot water storage operation, and performing an instant hot water circulation operation of circulating the hot water discharged from the hot water storage unit through an instant hot water circulation passage and returning it to the hot water storage tank when there is no hot water supply use, wherein the control means learns and stores the actual heat quantity of circulation of the instant hot water circulation operation in a predetermined period, and calculates a heat quantity of hot water for circulation to be stored in the hot water storage tank for the next predetermined period based on the actual heat quantity of circulation. The hot water storage supply system is characterized by this.

2. It has a water supply passage for supplying water to the hot water storage tank and water supply temperature detection means for detecting the water supply temperature of the water supply passage, wherein when the control means determines that it is winter based on the water supply temperature, the control means calculates the heat quantity of hot water for circulation so as to compensate for the decrease in the heat quantity due to heat dissipation from the hot water storage tank. The hot water storage supply system according to claim 1 is characterized by this.

3. It has a plurality of hot water storage supply devices each having the hot water storage unit and the heat source machine, wherein hot water is discharged from the plurality of hot water storage supply devices into the instant hot water circulation passage during hot water supply use, and the instant hot water circulation operation is configured to be performed by one preset hot water storage supply device. The hot water storage supply system according to claim 1 or 2 is characterized by this.

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