System and method for supplying hot water

Abstract

To improve not only efficiency due to stratified hot water storage and low-temperature heat storage by a hot water storage tank, but also convenience aspects such as general hot water supply, supply of hot water to a bath and bath reheating.SOLUTION: A system for supplying hot water includes: a heat source machine (heat pump unit 6) that can heat supplied water and obtain at least first hot water (HW1) and / or second hot water (HW2); a hot water storage tank (tank unit 4) with a first hot water outlet (take-out port 13-1) that takes out the first water or the second hot water and a second hot water outlet (take-out port 13-2) that takes out the first hot water, which stores the first water and stores the second water on the upper side of the first hot water; a hot water outflow passage (14) that during hot water outflow, flows out the first hot water or the second hot water from the first hot water outlet, or flows out the first hot water from the second hot water outlet; and a valve (three-way valve 15-1) that adjusts an opening on the first hot water outlet side and / or an opening on the second hot water outlet side, and flows out the first hot water and / or the second hot water to the hot water outflow passage.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a hot water supply system and method, for example, including a heat pump in a heat source unit, storing hot water obtained by the heat source unit in a hot water storage tank to store heat, and using the hot water for heat exchange with supply water, general hot water supply, bath water supply, bath reheating, etc. [Background technology]

[0002] For example, it is already known to store hot water obtained by heating a gas water heater in multiple hot water storage tanks and selectively supply hot water from the hot water storage tanks, or to generate hot water using a heat pump type heating source and store this hot water in the hot water storage tanks.

[0003] It is known that in a hot water storage system having a plurality of hot water storage tanks, hot water in each hot water storage tank is selectively circulated to a heating means for heating (for example, Patent Document 1).

[0004] In a system equipped with multiple hot water storage tanks and a heat pump type heating source, it is known that low-temperature water discharged from the hot water storage tank is heated by a heat exchanger of the heat pump type heating source, and this high-temperature water is stored in the hot water storage tank (for example, Patent Document 2). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2001-65982 A [Patent Document 2] JP 2007-298226 A Summary of the Invention [Problem to be solved by the invention]

[0006] Hot water storage systems that use multiple hot water storage tanks have issues such as high equipment costs, and there are also issues such as the deterioration of the heat storage efficiency of the hot water when hot water is moved between the heat source unit and multiple hot water storage tanks.

[0007] Conventionally, hot water supply systems equipped with a heat pump as the main heat source and a gas water heater as the auxiliary heat source store hot water heated by the heat pump in a hot water storage tank, and supplement the heat deficiency during hot water supply with the gas water heater. This type of hybrid hot water supply is affected by the operating costs of the main heat source unit, such as nighttime operation, and has issues such as the inability to maintain permanent low costs.

[0008] Therefore, an object of the present disclosure is to improve the efficiency of stratified hot water storage and low-temperature heat storage in a hot water storage tank, as well as to increase the convenience of general hot water supply, bath water filling, bath reheating, etc. [Means for solving the problem]

[0009] In order to achieve the above object, according to one aspect of the hot water supply system of the present disclosure, the system includes a heat source unit that heats supply water and obtains at least first hot water of a first set temperature and / or second hot water of a second set temperature higher than the first set temperature, a hot water storage tank that stores the first hot water and stores the second hot water above the first hot water, and is equipped with a first hot water outlet for taking out the first hot water or the second hot water and a second hot water outlet for taking out the first hot water, a hot water outlet path that, when discharging hot water, causes the first hot water or the second hot water to be discharged from the first hot water outlet or causes the first hot water to be discharged from the second hot water outlet, and a valve interposed between the first hot water outlet and the second hot water outlet and the hot water outlet path to adjust the opening degree of the first hot water outlet side and / or the opening degree of the second hot water outlet side and causes the first hot water and / or the second hot water to be discharged to the hot water outlet path.

[0010] In this hot water supply system, a temperature difference between the first hot water and the second hot water may be 10° C. or more.

[0011] In this hot water supply system, the second hot water outlet may be installed outside a hot water storage area in which the second hot water is stored, or may be installed within a hot water storage area in which the first hot water is stored.

[0012] This hot water supply system may include a plurality of temperature sensors that detect temperature information of the first hot water and / or the second hot water stored in the hot water storage tank, and a control unit that judges the first hot water and / or the second hot water based on the temperature information, controls the switching or opening of the valve based on the judgment result, and discharges the first hot water from the second hot water outlet to the hot water outlet path.

[0013] This hot water supply system may include a hot water supply path that supplies a third hot water obtained by mixing the first hot water or the second hot water with the supply water, a regulating valve that regulates the amount of the third hot water supplied, a distribution valve that distributes the supply water to the hot water supply path and the hot water storage tank, and a temperature sensor that detects temperature information of the third hot water, and the control unit may acquire the temperature information and control the opening of the regulating valve and / or the distribution valve, thereby controlling the third hot water to a hot water supply setting temperature.

[0014] In this hot water supply system, the hot water storage tank may include a buffer section that buffers the hot water flow in the hot water storage tank when hot water is introduced.

[0015] In this hot water supply system, the second hot water outlet may include an outlet direction regulating unit for extracting the first hot water, and may extract the first hot water located on a lower layer side of the hot water storage tank.

[0016] In order to achieve the above-mentioned objectives, according to one aspect of the hot water supply method disclosed herein, the method includes a step in which a heat source unit heats supply water to at least first hot water of a first set temperature and / or second hot water of a second set temperature higher than the first set temperature, a step in which the first hot water is stored in a hot water storage tank and the second hot water is stored above the first hot water, and a step in which a control unit, when discharging hot water, adjusts the opening degree of the first hot water outlet side and the second hot water outlet side of the valve to discharge the first hot water and / or the second hot water from the first hot water outlet to the hot water outlet path, or discharges the first hot water from the second hot water outlet to the hot water outlet path.

[0017] In this hot water supply method, a temperature difference between the first hot water and the second hot water may be 10° C. or more.

[0018] This hot water supply method may include a step in which a temperature sensor detects temperature information representing the first hot water and / or the second hot water, and a step in which a control unit acquires the temperature information and determines whether the first hot water and / or the second hot water is stored, controls the switching or opening of the valve based on the determination result, and causes the first hot water to be discharged from the second hot water outlet to the hot water outlet path.

[0019] This hot water supply method may include a step of exchanging heat between the second hot water tapped from the hot water storage tank and bath water.

[0020] This hot water supply method may include a step of adjusting the third hot water obtained by mixing the first hot water discharged from the second hot water outlet with supply water to a hot water outlet set temperature and supplying the third hot water, and a step of heating the supply water to the second hot water using the heat source unit and storing the second hot water in the hot water storage tank during hot water supply. Effect of the Invention

[0021] As described above, according to the present disclosure, any of the following effects can be obtained. (1) It is possible to provide a hot water supply system that achieves high efficiency through stratified hot water storage and low-temperature thermal storage in a hot water storage tank, and also provides improved convenience for hot water heat exchange, general hot water supply, bath water supply, and bath reheating.

[0022] (2) The heat storage temperature can be changed according to the purpose, such as hot water heat exchange, general hot water supply, bath water supply, bath heat retention, and bath reheating, thereby improving the heat storage efficiency and hot water supply efficiency.

[0023] (3) At least the first hot water and the second hot water are stored in a stratified state in the hot water storage tank, and when hot water is discharged, the first hot water or the second hot water can be taken out from the first hot water outlet and discharged into the hot water outlet passage, and the first hot water can be taken out from the second hot water outlet and discharged into the hot water outlet passage, thereby increasing the freedom to select the discharge hot water or the discharge temperature.

[0024] (4) The first hot water or the second hot water can be discharged from the hot water storage tank, and either of these hot waters can be mixed with supply water and adjusted to the hot water supply setting temperature to be supplied. [Brief description of the drawings]

[0025] [Figure 1] FIG. 1 is a diagram showing a hot water supply system according to a first embodiment. [Diagram 2] FIG. 2 is a diagram illustrating an example of a heat pump unit. [Diagram 3] FIG. 3 is a diagram showing a control system for the hot water supply system. [Figure 4] FIG. 4 is a diagram showing an operation pattern of the hot water supply system according to the second embodiment. [Diagram 5] FIG. 5A is a diagram showing the state of waiting before automatic pouring of hot water into the bath, and FIG. 5B is a flow chart showing the process of waiting before automatic pouring of hot water into the bath. [Figure 6] FIG. 6A is a diagram showing the operation during automatic bath water pouring, and FIG. 6B is a flow chart showing the processing during automatic bath water pouring. [Figure 7] FIG. 7 shows the state after automatic bath water pouring has ended. [Figure 8] FIG. 8A is a diagram showing the operation during bath temperature maintenance, and FIG. 8B is a flow chart showing the processing during bath temperature maintenance. [Figure 9]FIG. 9A is a diagram showing the operation during bath warming and reheating, and FIG. 9B is a flow chart showing the processing during bath warming and reheating. [Figure 10] FIG. 10A is a diagram showing the operation during bath warming and reheating, and FIG. 10B is a flow chart showing the processing during bath warming and reheating. [Figure 11] FIG. 11A is a diagram showing the operation during bath warming and heat storage start, and FIG. 11B is a flow chart showing the process during bath warming and heat storage start. [Figure 12] FIG. 12A is a diagram showing the operation of keeping the bath warm and using hot water supply, and FIG. 12B is a flow chart showing the processing of keeping the bath warm and using hot water supply. [Figure 13] FIG. 13 is a diagram showing the state when bath temperature is being kept warm and hot water supply has ended. [Figure 14] FIG. 14A is a diagram showing the operation of the heat storage for hot water supply after automatic bath water pouring has been completed in the third embodiment, and FIG. 14B is a diagram showing the operation after the amount of heat for hot water supply has been secured. [Figure 15] FIG. 15A is a perspective view showing a hot water inlet / outlet structure of a hot water storage tank unit according to a fourth embodiment, and FIG. 15B is a cross-sectional view showing the hot water inlet / outlet structure of the hot water storage tank unit. [Figure 16] 16A and 16B are diagrams showing an example of the opening shape of the hot water outlet port. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] First Embodiment Fig. 1 shows a hot water supply system 2 according to a first embodiment. The configuration shown in Fig. 1 is an example, and the present disclosure is not limited to such a configuration.

[0027] The hot water supply system 2 includes a hot water storage tank unit 4 (hereinafter referred to as "tank unit 4"), a heat pump unit 6 (hereinafter referred to as "HP unit 6"), a hot water supply control unit 8, and a remote control device 10 (hereinafter referred to as "remote control 10").

[0028] Tank unit 4 is an example of a hot water storage tank of the present disclosure, and has a hot water storage capacity of, for example, about 380 liters. This tank unit 4 has a water supply passage 12 connected to the lower layer side, a first hot water extraction port 13-1 (hereinafter referred to as "extraction port 13-1") on the upper layer side, a second hot water extraction port 13-2 (hereinafter referred to as "extraction port 13-2") on the middle layer side, and is connected to a hot water outlet passage 14 via a first three-way valve 15-1 (hereinafter referred to as "three-way valve 15-1").

[0029] The tank unit 4 stores first hot water HW1 (hereinafter referred to as "hot water HW1") and / or second hot water HW2 (hereinafter referred to as "hot water HW2") as low-temperature heat storage, and for example, when hot water is discharged, supply water (for example, supply water W before heating) is stored. The hot water HW1 is hot water heated to a first set temperature Tc1 (for example, hot water of 40°C to 45°C). The hot water HW2 is hot water heated to a second set temperature Tc2 (for example, hot water of 60°C to 65°C). Although the temperatures of the hot water HW1 and the hot water HW2 are exemplified, the temperature difference between the hot water HW1 and the hot water HW2 may be 10°C or more, more preferably 20°C or more, and is not limited to the exemplified temperatures as long as it is a temperature suitable for low-temperature heat storage.

[0030] Therefore, in the tank unit 4, the supply water W is stored in the bottom layer, the hot water HW1 is stored in a layer above the supply water W, and the hot water HW2 is stored in the top layer in a stratified manner. This stratified hot water storage is a hot water storage state in which the hot water HW1 is in the bottom layer and the hot water HW2 is in the top layer due to the relationship between specific gravity and gravity, which depends on the temperatures of the hot water HW1 and hot water HW2. A strict temperature division is not essential for this hot water storage state, and it is a hot water storage state of different temperatures that includes such stratification.

[0031] The extraction port 13-1 is an example of a first hot water extraction port for extracting hot water HW1 or hot water HW2 from the tank unit 4, for example, when discharging hot water. The extraction port 13-2 is an example of a second hot water extraction port for extracting hot water HW1 from the tank unit 4, for example, when supplying hot water. This extraction port 13-2 is installed outside the hot water storage area of ​​the hot water HW2, such as below the hot water storage area of ​​the hot water HW2, with respect to the tank unit 4 in which the hot water HW1 and / or hot water HW2 are stored, or is installed within the hot water storage area of ​​the hot water HW1.

[0032] Three-way valve 15-1 is an example of a valve of the present disclosure that is interposed between extraction ports 13-1 and 13-2 and hot water outlet path 14 under the control of hot water supply control unit 8, and adjusts the opening degree of extraction port 13-1 side or the opening degree of extraction port 13-2 side or selects extraction ports 13-1 and 13-2, and discharges hot water HW1 and / or hot water HW2 to hot water outlet path 14.

[0033] When hot water is discharged, the water supply W is supplied from the water supply passage 12 to the tank unit 4, and hot water HW1 can be discharged from the tank unit 4 to the hot water discharge passage 14.

[0034] A distribution valve 16 is provided in the water supply passage 12, and a flow rate regulation valve 18 is provided in the hot water supply passage 22. A bypass passage 20 that bypasses the tank unit 4 is connected between the distribution valve 16 and the flow rate regulation valve 18. The distribution valve 16 and the flow rate regulation valve 18 are, for example, configured as a single valve unit. The distribution ratio of the distribution valve 16 is controlled by the hot water supply control unit 8. This distribution valve 16 distributes a predetermined amount of feed water W to the tank unit 4 and the bypass passage 20 according to the set distribution ratio. The flow rate regulation valve 18 regulates the amount of hot water supplied from the third hot water HW3 (hereinafter referred to as "hot water HW3") obtained by mixing the feed water W on the bypass passage 20 side with the hot water HW1 or hot water HW2 on the hot water outlet passage 14 side. In this case, the hot water HW3 is regulated to a desired amount of hot water supplied and adjusted to a preset water supply set temperature.

[0035] <HPユニット6> The HP unit 6 is an example of a heat source machine for heating the feedwater W to hot water HW1 or hot water HW2. The HP unit 6 includes a pump 24 and an HP (heat pump) control unit 26. When the HP unit 6 is driven, the pump 24 is operated under the control of the HP control unit 26 to circulate and heat the feedwater W, etc. Therefore, the HP unit 6 can heat the feedwater W, etc. to hot water HW1 or hot water HW2, and store either of them in the tank unit 4 at an appropriate time.

[0036] <1st circulation path 28-1 to 4th circulation path 28-4, additional heating circulation path 30> The HP unit 6 and the tank unit 4 are provided with a first circulation path 28-1, a second circulation path 28-2, a third circulation path 28-3, and a fourth circulation path 28-4, and a reheating circulation path 30 is provided in addition to the fourth circulation path 28-4.

[0037] First circulation path 28-1: A flow path from the lower layer side of the tank unit 4 to the inlet side of the HP unit 6, and is equipped with a second three-way valve 15-2 (hereinafter simply referred to as "three-way valve 15-2"). This three-way valve 15-2 is controlled by the hot water supply control unit 8, and is used to select either the supply water W from the tank unit 4 or the hot water HW1 or hot water HW2 after heat exchange.

[0038] Second circulation path 28-2: A flow path from the outlet side of HP unit 6 to the upper side of tank unit 4, and equipped with a third three-way valve 15-3 (hereinafter simply referred to as "three-way valve 15-3"). This three-way valve 15-3 is controlled by hot water supply control unit 8, and is used to select whether the destination of circulating water from HP unit 6 is the upper layer or the lower layer of tank unit 4.

[0039] Third circulation path 28-3: A flow path from the three-way valve 15-3 to the lower side of the tank unit 4. That is, the second circulation path 28-2 or the third circulation path 28-3 on the outlet side of the HP unit 6 is selectively switched by the three-way valve 15-3.

[0040] Fourth circulation path 28-4: A flow path extending from the upper side of the tank unit 4 to the three-way valve 15-2 located on the lower side of the tank unit 4.

[0041] Reheating circulation path 30: A flow path that circulates bath water BW during bath reheating operation.

[0042] A heat exchanger 36 is installed in the fourth circulation path 28-4, and a reheating circulation path 30 is connected to this heat exchanger 36. A circulation port 40 of a bath 38 is connected to this reheating circulation path 30, and a pump 42 is installed. During bath reheating operation, the pump 42 is driven to circulate bath water BW through the reheating circulation path 30 to the heat exchanger 36.

[0043] <Temperature sensors 44-1 to 44-13> In this hot water supply system 2, temperature sensors 44-1, 44-2, 44-3, 44-4, 44-5, 44-6, 44-7, 44-8, 44-9, 44-10, 44-11, 44-12, and 44-13 are provided for each temperature detection target.

[0044] Temperature sensors 44-1, 44-2, 44-3, 44-4, 44-5: Installed, for example, at equal intervals from the top to the bottom of the tank unit 4, with the temperature sensor 44-1 detecting the temperature T1 of the top layer, the temperature sensor 44-5 detecting the temperature T5 of the bottom layer, and the temperature sensors 44-2, 44-3, 44-4 detecting the temperatures T2, T3, T4 of the intermediate layers extending from the top to the bottom. The hot water supply control unit 8 acquires temperature information from the temperature sensors 44-1, 44-2, 44-3, 44-4, 44-5, and uses the installation positions of the temperature sensors 44-1, 44-2, 44-3, 44-4, 44-5 to detect or determine the amount of hot water HW2 stored in the tank unit 4, the amount of hot water HW1 stored, the amount of water W injected, and the like.

[0045] Temperature sensor 44-6: Installed on first circulation path 28-1, detects temperature T6 on the inlet side of HP unit 6.

[0046] Temperature sensor 44-7: Installed on second circulation path 28-2, and detects temperature T7 on the outlet side of HP unit 6.

[0047] Temperature sensor 44-8: Installed in hot water outlet passage 14, detects temperature T8 of hot water HW1 or hot water HW2 discharged from tank unit 4.

[0048] Temperature sensor 44-9: Installed in the fourth circulation path 28-4, and detects the temperature T9 of the hot water HW2 after heat exchange in the heat exchanger 36.

[0049] Temperature sensors 44-10, 44-11: The temperature sensors 44-10, 44-11 are installed in the reheating circuit 30. The temperature sensor 44-10 detects a temperature T10 on the inlet side of the heat exchanger 36, and the temperature sensor 44-11 detects a temperature T11 on the outlet side of the heat exchanger 36.

[0050] Temperature sensor 44-12: Installed in the water supply passage 12 to detect the temperature T12 of the water supply W entering the distribution valve 16.

[0051] Temperature sensor 44-13: Installed in hot water supply passage 22, detects temperature T13 on the outlet side of flow rate regulating valve 18.

[0052] Hot water supply control unit 8 acquires input information such as operation information from remote control 10, temperature information from temperature sensors 44-1 to 44-13, and flow rate information from a flow rate sensor, and controls functional units such as distribution valve 16, flow rate regulating valve 18, three-way valves 15-2 and 15-3, and pump 42 to execute operation modes such as hot water storage, hot water supply, and bath reheating. The control of this hot water supply control unit 8 includes information such as information presented by remote control 10, and cooperative control with HP control unit 26 for hot water storage, etc.

[0053] Remote control 10 is used to set a first set temperature Tc1 for generating hot water HW1, a second set temperature Tc2 for generating hot water HW2, instruct hot water supply, and display the hot water supply state. Remote control 10 is used for linkage control with hot water supply control unit 8 and HP control unit 26. Linkage relationships between hot water supply control unit 8 and HP control unit 26 can be assumed in various ways, such as wireless connection or wired connection, and are not limited to the wired connection shown in the figure.

[0054] The HP control unit 26 realizes cooperative control with the remote control 10 or the hot water supply control unit 8, and controls the heat pump to generate either the hot water HW1 or the hot water HW2.

[0055] <HPユニット6> 2 shows an example of the HP unit 6. This HP unit 6 includes a refrigerant circuit 46, a heat exchanger 48-1, a heat exchanger 48-2, an expansion valve 50, an air heat exchanger 52, a compressor 54, and a part of the first circuit 28-1 described above.

[0056] A refrigerant 56 circulates through the refrigerant circulation path 46. A propane refrigerant (e.g., R290) or the like is used as the refrigerant 56, which is suitable for low-temperature heat storage in the tank unit 4. The heat exchanger 48-1 exchanges heat between the refrigerant 56 flowing through the refrigerant circulation path 46 and the feed water W or the hot water HW2 whose temperature has been lowered after heat exchange flowing through the first circulation path 28-1, to generate hot water HW1 or hot water HW2.

[0057] In this HP unit 6, a temperature sensor 44-14 detects the inlet temperature of the heat exchanger 48-1, and a temperature sensor 44-15 detects the outlet temperature of the heat exchanger 48-1. A temperature sensor 44-16 detects the temperature of the air heat exchanger 52, a temperature sensor 44-17 detects the temperature of the refrigerant 56 exiting the air heat exchanger 52, and a temperature sensor 44-18 detects the temperature of the refrigerant 56 after compression by the compressor 54. These detected temperature information are provided to the HP control unit 26 and used for controlling the temperature of the refrigerant 56, etc.

[0058] The heat exchanger 48-2 exchanges heat between the refrigerant 56 whose temperature has been lowered by the heat exchange in the heat exchanger 48-1 and the refrigerant 56 after the heat exchange in the air heat exchanger 52. The expansion valve 50 reduces the pressure of the refrigerant 56 to expand it. After the pressure reduction, the refrigerant 56 is guided to the air heat exchanger 52, where it absorbs heat from the air through heat exchange with the air. The compressor 54 compresses the refrigerant 56 to increase its temperature. In the heat exchanger 48-1, the heat of the refrigerant 56 is exchanged with the water supply W or the like. In this heat exchange, if the target temperature is the first set temperature Tc1, the temperature of the hot water HW1 is increased, and if the target temperature is the second set temperature Tc2, the temperature of the hot water HW2 is increased.

[0059] <Control System 58> 3 shows a control system 58 in the hot water supply system 2. This control system 58 is an example of the control unit of the present disclosure.

[0060] This control system 58 is equipped with a hot water supply control unit 8, a remote control 10, and an HP control unit 26. The hot water supply control unit 8 is composed of a computer with a communication function, and includes a processor 60, a memory unit 62, an input / output unit (I / O) 64, a communication unit 66, etc. The processor 60 executes an OS (Operating System) and a control program in the memory unit, and performs calculation processing, learning processing, and control of various functional units. The memory unit 62 stores the OS and the control program, and the control program includes a database used for calculation and control. The I / O 64 acquires control information such as temperatures T1 to T13, and inputs control signals and drive signals output by the processor to the functional units.

[0061] The remote control 10 is composed of a computer with communication capabilities and is installed in the kitchen, bathroom, etc., and is used for coordinating operations of the hot water supply control unit 8 or the HP control unit 26, and for presenting control information provided by the hot water supply control unit 8 or the HP control unit 26.

[0062] The HP control unit 26 is composed of a computer equipped with a communication function, and performs control in cooperation with the hot water supply control unit 8 and control based on operation input from the remote control 10. It receives settings such as the first set temperature Tc1 and the second set temperature Tc2 as the above-mentioned target temperatures, and performs heat exchange to generate hot water HW1 and HW2.

[0063] <Advantages of the First Embodiment> According to the first embodiment, any one of the following effects can be obtained. (1) According to the tank unit 4 of this hot water supply system 2, during hot water supply, hot water HW2 can be taken out from the outlet port 13-1, and hot water HW1 can be taken out from the outlet port 13-2. If there is no hot water HW2 in the tank unit 4, hot water HW1 can also be taken out from the outlet port 13-1.

[0064] (2) During hot water supply, the three-way valve 15-1 can be switched to the extraction port 13-1 or the extraction port 13-2 under the control of the hot water supply control unit 8, and when the extraction port 13-1 is selected, the hot water HW2 or hot water HW1 taken out of the extraction port 13-1 can be discharged to the hot water outlet passage 14. When the extraction port 13-2 is selected, the hot water HW1 can be discharged to the hot water outlet passage 14.

[0065] (3) When supplying hot water, the hot water HW2 or hot water HW1 discharged from the hot water outlet path 14 is joined by the supply water W from the bypass path 20 at the distribution valve 16, and the two are mixed to obtain hot water HW3 (= hot water HW1 + supply water W or hot water HW2 + supply water W), and this hot water HW3 can be supplied to the hot water supply path 22.

[0066] (4) In addition, it is possible to obtain operations such as automatic bath water pouring, bath warming, bath warming reheating, and bath warming heat storage, which will be disclosed in the operation patterns described later.

[0067] Second Embodiment <Operation pattern of hot water supply system 2> 4 shows an example of an operation pattern of the hot water supply system 2 according to the second embodiment. Each operation pattern is an example of a hot water supply method of the present disclosure. This hot water supply method includes a method of supplying water W and a method of discharging hot water HW1 or hot water HW2.

[0068] The operating patterns of this hot water supply system 2 include a state waiting before automatically pouring hot water into the bath (this state includes a stopped state, a standby state, or an operating state), processing (S100: A, B in Figure 5), operation during automatic bath pouring (S200: A, B in Figure 6), state when automatic bath pouring has ended (S300: Figure 7), operation during bath keeping warm (S400: A, B in Figure 8), operation during bath keeping and reheating (initial heating) (S500: A, B in Figure 9), operation during bath keeping and reheating (combined with heating by HP unit 6) (S600: A, B in Figure 10), operation during bath keeping warm and starting heat storage (S700: A, B in Figure 11), operation during bath keeping warm and using hot water (S800: A, B in Figure 12), operation during bath keeping warm and ending hot water supply (S900: Figure 13), etc. It is then possible to return from the bath warming / hot water supply completed state (S900) to the standby state before automatic bath hot water pouring (S100) via any of the above operations.

[0069] Operation during standby before automatic bath water pouring (S100): Hot water HW1 heated to a first set temperature Tc1 is stored in the tank unit 4. The hot water supply control unit 8 obtains temperature information from temperature sensors 44-1, . . . , 44-5, etc., and the hot water HW1 is maintained by the heating operation of the HP unit 6.

[0070] Operation during automatic bath water pouring (S200): During automatic bath water pouring, hot water HW1 from tank unit 4 is used, and hot water HW3 is poured from hot water supply path 22 into bath 38.

[0071] Operation for ending automatic bath water pouring (S300): When a predetermined amount of hot water HW1 has been poured into the bath 38, the automatic bath water pouring is ended.

[0072] Operation while keeping bath warm (S400): While keeping the bath warm, hot water HW1 is consumed to fill the bath, the water supply W supplied to the tank unit 4 is heated by the HP unit 6, and hot water HW2 is stored in the tank unit 4 in preparation for reheating the bath.

[0073] Operation during bath warming and reheating (initial heating) (S500): When bath reheating occurs during bath warming, the bath water BW is heated to the bath set temperature using hot water HW2 stored in tank unit 4.

[0074] Operation during bath warming and reheating (combined with heating by HP unit 6) (S600): When hot water HW2 is consumed from tank unit 4 during bath reheating, the hot water HW2 in tank unit 4 is depleted. Therefore, the hot water HW2 obtained by heating by HP unit 6 is circulated to heat exchanger 36 to exchange heat with bath water BW, and the temperature of bath water BW is raised to the bath water set temperature.

[0075] Bath warming / heat storage start operation (S700): While the bath is warming, the water W in the tank unit 4 is led to the HP unit 6 and heated, and the hot water HW2 in the tank unit 4 is stored.

[0076] Bath warming / hot water supply operation (S800): When hot water is required while the bath is warmed, hot water HW2 is dispensed from the tank unit 4, and hot water supply at the set temperature is started using this hot water HW2 and the water supply W. In this case, hot water HW2 is dispensed from the tank unit 4, and a predetermined amount of hot water HW3 stored in the tank unit 4, for example 20 liters, is maintained in the tank unit 4.

[0077] Bath warming / hot water supply end operation (S900): When hot water supply ends, the system switches to heat storage operation, water W is guided from tank unit 4 to HP unit 6 and heated, and hot water HW2 is stored in tank unit 4.

[0078] <Bathroom automatic pouring standby state> A in Fig. 5 shows the state of standby before automatic bath water pouring. During standby before automatic bath water pouring, hot water HW1 is stored in the tank unit 4, and the heat storage state of the hot water HW1 is maintained in the tank unit 4. This maintenance includes heating control by the HP unit 6.

[0079] B in Fig. 5 shows the processing procedure during the standby before automatic hot water supply to the bathtub. The hot water supply control unit 8 acquires the temperature information of the tank unit 4 from the temperature sensors 44-1, 44-2, 44-3, 44-4, and 44-5 (S101), and determines whether each detected temperature Tn (where n = 1, 2, 3, 4, 5) is equal to or higher than the first set temperature Tc1 (S102).

[0080] If Tn < Tc1 (NO in S102), the hot water supply control unit 8 operates the pump 24 from the time when Tn < Tc1 is reached (S103), performs the heating operation by the HP unit 6, and returns to S101. As a result, the hot water HW1 in the tank unit 4 is controlled to the first set temperature Tc1, the hot water HW1 is stored in the tank unit 4, and the heat storage state is maintained.

[0081] If Tn ≥ Tc1 (YES in S102), the pump 24 is stopped and the heating operation by the HP unit 6 is stopped (S104). After the pump 24 is stopped, it is determined whether to shift to automatic hot water supply to the bathtub (S105). If not shifting to automatic hot water supply to the bathtub (NO in S105), the standby before automatic hot water supply to the bathtub is continued, and if it is automatic hot water supply to the bathtub (YES in S105), it shifts to during automatic hot water supply to the bathtub (S200). This control is an example, and the control during the standby before automatic hot water supply to the bathtub is not limited to the above.

[0082] <Operation during automatic hot water supply to the bathtub> A in Fig. 6 shows the operation during automatic hot water supply to the bathtub. In the figure, the thick line represents the supply state of the water supply W and the hot water discharge state of the hot water HW1. During automatic hot water supply to the bathtub, the hot water HW1 is discharged from the tank unit 4 to the hot water discharge path 14, and at this time, the water supply W flows through the water supply path 12 and the bypass path 20. For this bathtub hot water supply, the hot water HW3, which is the mixed water of the hot water HW1 and the water supply W, is used, and this hot water HW3 is poured into the bathtub 38 through the hot water supply path 22.

[0083] B in Fig. 6 shows the processing procedure during automatic bath water pouring. Hot water supply control unit 8 starts pouring hot water HW3 into bath 38 (S201), acquires temperature information of hot water HW1 and water supply W (S202), and controls the opening of distribution valve 16 to the opening ratio set to achieve the set hot water pouring temperature of bath 38 (S203). Hot water HW1 and water supply W are mixed by flow rate control valve 18 to obtain hot water HW3 adjusted to the set hot water pouring temperature. This hot water HW3 is poured into bath 38 from hot water supply path 22.

[0084] For example, hot water supply control unit 8 acquires flow rate information of hot water HW3 from a flow rate sensor (not shown), monitors the amount of hot water being poured into bath 38 (S204), and continues pouring if the amount of hot water HW3 has not reached a reference value (NO in S204). When the amount of hot water HW3 reaches the reference value (YES in S204), pouring is stopped (S205). After pouring is stopped, the process proceeds to keeping the bath warm (S400).

[0085] <Bath automatic pouring completed> Fig. 7 shows the state where the automatic bath water pouring has ended. At the end of this automatic bath water pouring, the amount of water supply W in the tank unit 4 has increased compared to the standby state before the automatic bath water pouring shown in Fig. 5A.

[0086] When hot water HW3 is used to fill the bath 38, the corresponding amount of water supply W enters the tank unit 4. In this example, the water supply W reaches the installation level of the temperature sensor 44-3. From this reached level, the amount of hot water HW1 used to fill the bath can be predicted or calculated.

[0087] <Bath warming operation> A in Fig. 8 shows the operation during bath warming. During bath warming, a predetermined amount of hot water HW2, for example 20 liters of hot water HW2, is supplied to and stored in the upper layer of tank unit 4 in preparation for bath reheating. During this bath warming, tank unit 4 stores supply water W in the lower layer, hot water HW1 in the middle layer, and hot water HW2 in the upper layer.

[0088] B in Fig. 8 shows the processing procedure during bath temperature keeping. When the system switches to bath temperature keeping, hot water supply control unit 8 switches three-way valve 15-2 (S401), switches three-way valve 15-3 (S402), drives pump 24 of HP unit 6 (S403), and causes feed water W to flow out of tank unit 4 and circulate to HP unit 6. The feed water W is heated to hot water HW2 in HP unit 6, and this hot water HW2 is stored in tank unit 4. In this case, when 20 liters of hot water HW2 are stored in tank unit 4, 20 liters of feed water W is heated to hot water HW2.

[0089] The hot water supply control unit 8 acquires the temperature information (Tn) and compares it with the second set temperature Tc2 (S404), and when Tn≧Tc2 is reached (YES in S404), it determines whether the amount of hot water HW2 stored in the tank unit 4 has reached a reference value (S405). If the amount of hot water HW2 has not reached the reference value (NO in S405), the hot water storage process continues, and when the amount of hot water HW2 has reached the reference value (YES in S405), it transitions to the bath warming reheating process (initial heating) (S500).

[0090] <Bathroom warming reheating (initial heating) operation> A in Fig. 9 shows the operation during bath warming and reheating (initial heating). Bath warming and reheating involves heat exchange between the hot water HW2 in the upper layer of the tank unit 4 and the bath water BW, and the bath water BW is heated to the reheating set temperature using the heat of the hot water HW2.

[0091] In this case, the three-way valve 15-2 is switched to connect the fourth circulation path 28-4 and the first circulation path 28-1, and the three-way valve 15-3 is switched to connect the first circulation path 28-1 and the third circulation path 28-3. At this time, when the pump 24 on the HP unit 6 side is operated, the hot water HW2 is taken out from the tank unit 4 and circulated to the heat exchanger 36, and the hot water HW2, which has been cooled after heat exchange, passes through the HP unit 6 and is introduced into the lower layer of the tank unit 4.

[0092] At this time, when the pump 42 of the reheating circulation path 30 is operated, the bath water BW circulates through the reheating circulation path 30 to the heat exchanger 36, and after heat exchange with the hot water HW2, the bath water BW can be reheated to the reheating set temperature.

[0093] 9B shows the processing procedure during bath warming and reheating (initial heating). When the hot water supply control unit 8 shifts to bath warming and reheating, it switches the three-way valve 15-2 (S501), switches the three-way valve 15-3 (S502), and drives the pump 24 of the HP unit 6 and the pump 42 of the reheating circulation path 30 (S503). This causes the hot water HW2 and bath water BW to circulate through the heat exchanger 36, and the bath water BW can be heated by the hot water HW2 through heat exchange between them. In other words, this initial heating heats the bath water BW using the hot water HW2 stored in the tank unit 4.

[0094] The hot water supply control unit 8 judges whether the initial heating has ended since the start of the bath warming and reheating (S504). This initial heating is continued, for example, until the end of the initial heating time or until the hot water HW2 reaches, for example, 20 liters (NO in S504). If the initial heating has ended (YES in S504), the process proceeds to bath warming and reheating (S600).

[0095] <Bathroom heating operation (HP unit 6 heating operation)> 10A shows the operation during bath warming and reheating (combined heating by the HP unit 6), that is, the operation after the initial heating of the bath warming and reheating is completed.

[0096] This bath warming and reheating uses hot water circulation, in which hot water HW2, which has been cooled by heat exchange with bath water BW during initial heating, is heated by HP unit 6. In this case, three-way valves 15-2, 15-3 are switched to connect first circulation path 28-1 and second circulation path 28-2 to form a circulation path, and hot water HW2, which has been heated by heating in HP unit 6, is circulated to second circulation path 28-2 and heat exchanger 36. Therefore, hot water HW2, which has been cooled by heat exchange with bath water BW, is heated by heating in HP unit 6, and then is again subjected to heat exchange with bath water BW.

[0097] In this circulation operation, the three-way valve 15-2 is switched to connect the fourth circulation path 28-4 and the first circulation path 28-1, and the three-way valve 15-3 is switched to connect the first circulation path 28-1 and the second circulation path 28-2. At this time, when the pump 24 on the HP unit 6 side is operated, the hot water HW2 heated by heating in the HP unit 6 is taken out and circulated to the heat exchanger 36, and the hot water HW2 cooled after heat exchange can be reheated in the HP unit 6 and then flowed into the heat exchanger 36.

[0098] At this time, the pump 42 of the reheating circulation path 30 continues to operate, so that the bath water BW circulates through the reheating circulation path 30 to the heat exchanger 36, and after heat exchange with the hot water HW2, the bath water BW can be reheated to the reheating set temperature.

[0099] 10B shows the processing procedure during bath warming and reheating (combined heating of HP unit 6). Even after the initial heating of bath warming and reheating is completed, hot water supply control unit 8 maintains the switched state of three-way valve 15-2 as in the initial heating, switches three-way valve 15-3 (S601), and keeps pump 24 of HP unit 6 and pump 42 of reheating circulation path 30 in operation (S602). Then, it increases the heating capacity of HP unit 6 (S603), raises the temperature of hot water HW2 that has been cooled after heat exchange with bath water BW, stores it in tank unit 4, and transitions to the start of heat storage during bath warming (S700).

[0100] <Bath warming / heat storage start operation> A in FIG. 11 shows the operation during bath warming and heat storage start. When bath reheating is performed during bath warming, hot water HW2 is consumed to heat the bath water BW, so the hot water HW2 in the tank unit 4 is depleted. In preparation for hot water supply, hot water HW2 starts to be stored in the tank unit 4. The hot water supply control unit 8 detects the depletion of hot water HW2 using temperature information obtained from the temperature sensor 44-1 and the like. In response to this, the hot water supply control unit 8 switches the three-way valve 15-2, connects the lower layer of the tank unit 4 to the first circulation path 28-1, drives the HP unit 6 to guide the water supply W from the tank unit 4 to the HP unit 6 and heats it to the second set temperature Tc2, and guides the hot water HW2 obtained in the HP unit 6 through the second circulation path 28-2 to the tank unit 4 for storage. In this case, if the hot water HW1 is insufficient after the hot water supply is started, the hot water HW1 may be stored in the tank unit 4, and then the hot water HW2 may be stored.

[0101] FIG. 11B shows the processing procedure for bath warming / heat storage start. Hot water supply control unit 8 monitors the end of bath reheating (S701), and when bath reheating is finished (YES in S701), switches three-way valve 15-2 (S702) and connects first circulation path 28-1 to the lower part of tank unit 4. The heating operation of HP unit 6 is maintained (S703), and water supply W is heated to second set temperature Tc2. Hot water HW2 obtained by this heating is stored in tank unit 4 (S704), and the operation proceeds to bath warming / hot water supply use (S800).

[0102] <Bathroom warming / hot water supply in use> A in Fig. 12 shows the operation of keeping the bath warm and using hot water supply. When supplying hot water during the bath warming and heat storage operation, the three-way valve 15-1 is switched to close the extraction port 13-1 and open the extraction port 13-2, so that hot water HW1 is discharged from the tank unit 4 to the hot water outlet 14 from the extraction port 13-2, and this hot water HW1 is used for hot water supply. To adjust the hot water supply temperature, a part of the water supply W supplied to the tank unit 4, which is distributed by the distribution valve 16, is mixed with the hot water HW1, and hot water supply is started with the hot water HW3 adjusted to the set temperature. In this case, the hot water HW2 stored in the tank unit 4 is maintained in the tank unit 4. In other words, it is possible to prepare for future hot water supply or reheating.

[0103] Fig. 12B shows the processing procedure when the bath is kept warm and hot water is being used. In this case, the heat storage operation is stopped when hot water is being used.

[0104] In the hot water supply operation, it is determined whether a demand for hot water has arisen (S801), and if a demand for hot water has arisen (YES in S801), hot water HW2 is discharged from the tank unit 4 to the hot water outlet passage 14 in response to the demand for hot water, and supply water W enters the tank unit 4 from the water supply passage 12 in response to this discharge (S802). The hot water supply control unit 8 acquires temperature information from the temperature sensors 44-8, 44-12, 44-13, etc., and controls the opening of the distribution valve 16 to adjust the hot water supply temperature to the set temperature (S803), and supplies hot water by regulating the amount of hot water HW3 adjusted to the set temperature with the flow rate regulation valve 18 (S804). The hot water supply control unit 8 monitors the hot water supply (S805), and continues the hot water supply until the hot water supply is completed (NO in S805, S804), and when the hot water supply is completed (YES in S805), it returns to S801.

[0105] During this hot water supply, the feed water W enters the tank unit 4 from the water supply passage 12 and accumulates in the lower layer of the hot water HW1.

[0106] <Bath warming in progress / Hot water supply finished> Fig. 13 shows the state when the bath is being kept warm and hot water supply has ended. When hot water supply is ended during bath warming, the operation proceeds to the same as the operation during bath warming and heat storage start (Fig. 11) described above. In other words, the supply of water W to the tank unit 4 is stopped.

[0107] <Advantages of the second embodiment> According to the second embodiment, any one of the following effects can be obtained. (1) In standby mode before automatic bath water pouring, hot water HW1 is stored in tank unit 4, and the heat stored in the hot water HW1 can be used to supply hot water and pour hot water into the bath.

[0108] (2) In the automatic bath water pouring system, hot water can be poured into the bath using hot water HW1 from the tank unit 4.

[0109] (3) At the end of automatic bath water pouring, temperature information is obtained from temperature sensors 44-1, 44-2, ..., 44-5, making it possible to know the amount of water W being supplied in tank unit 4 (i.e., the amount of hot water HW1 being attenuated) or the amount of hot water HW1 stored, and therefore the amount of replenishment of hot water HW1 or hot water HW2.

[0110] (4) During bath warming, the water W supplied to the tank unit 4 for bath hot water supply is circulated through the HP unit 6 and heated to hot water HW1 or hot water HW2, so that a predetermined amount of hot water HW1 or hot water HW2 can be stored in the tank unit 4.

[0111] (5) During bath warming and reheating, the bath water BW can be initially heated using hot water HW2 from tank unit 4, thereby increasing the rate at which the bath water BW rises in temperature during bath reheating.

[0112] (6) When the bath is kept warm, by using the HP unit 6 for heating as well, the bath water BW can be heated without consuming the heat stored in the tank unit 4 due to the heat exchange between the bath water BW and the hot water HW2.

[0113] (7) During bath warming and while the bath water BW is being reheated or after that time has elapsed, the water W in the tank unit 4 is guided to the HP unit 6 and heated in preparation for hot water supply, so that the tank unit 4 can be replenished with hot water HW2.

[0114] (8) During bath warming, hot water HW1 in the lower layer of hot water HW2 can be selectively discharged from tank unit 4 using outlet port 13-2, and supply water W can be led from water supply passage 12 to tank unit 4 and the bypass passage to supply hot water HW at a predetermined temperature, which is a mixture of hot water HW2 and supply water W. At this time, hot water HW2 in tank unit 4 is maintained, so heat can be stored without the need for operations such as refilling hot water HW2.

[0115] (9) During bath heating, even after hot water supply is stopped, water W can be introduced from tank unit 4 to HP unit 6 and heated, and hot water HW2 can be replenished to tank unit 4 and stored as heat, thereby enabling efficient heat storage using hot water HW1 and / or hot water HW2.

[0116] (10) In this hot water supply system 2, a propane refrigerant (R290), which has good thermal efficiency at low temperatures (e.g., below 60°C), is used as refrigerant 56. The system is primarily based on low-temperature heat storage. As a result, the thermal efficiency (COP) of the HP unit 6 is COP: 6.0 for heat storage using hot water HW1 (e.g., 45°C) and COP: 4.7 for heat storage using hot water HW2 (e.g., 60°C), confirming that the thermal efficiency is high.

[0117] (11) This hot water supply system 2 can achieve highly efficient operation without controlling the start and stop of the heat storage operation based on the electricity fee. As mentioned above, heat is stored in hot water HW1 (45°C = remote control set temperature + 5°C) except for automatic bath water pouring and keeping warm, and after automatic bath water pouring is finished (= keeping warm), a certain amount (about 20 liters) of hot water HW2 (for example, 65°C) is stored in the upper layer of the tank unit 4, and when bath reheating is started, heat is exchanged between the hot water HW2 and the bath water BW until the heat output of the HP unit 6 stabilizes (for example, about 3 minutes), and the bath water BW can be heated to the reheating set temperature.

[0118] In addition, if hot water is required for the shower or faucet before the bath is reheated, hot water is supplied as hot water HW2, and if the amount of hot water HW2 in the tank unit 4 decreases, the hot water HW2 can be replenished to the tank unit 4 by heating it in the HP unit 6.

[0119] (12) As described above, the heating capacity of the HP unit 6 and the hot water storage capacity of the tank unit 4 are combined to change the heat storage temperature according to the purpose, such as general hot water supply, bath hot water supply, bath heat retention, and bath reheating, thereby improving the heat storage efficiency and hot water supply efficiency.

[0120] (13) Since either the hot water HW1 or the hot water HW2 can be generated using the HP unit 6 and no other auxiliary heat source is required, the system can be simplified.

[0121] (14) When hot water HW1 is poured into the bath from the tank unit 4, hot water HW2 is stored in the tank unit 4, so that bath reheating and general hot water supply can be performed quickly without causing a shortage of heat, thereby increasing convenience.

[0122] Third embodiment 14A and 14B show an operation pattern of the hot water supply system 2 according to the third embodiment. This operation pattern is an example of the hot water supply method of the present disclosure. In 14A and 14B, the same parts as in FIG. 1 are denoted by the same reference numerals.

[0123] It is expected that the amount of heat stored for hot water supply will be insufficient as a result of using hot water HW1 for automatic bath water pouring. Therefore, in the third embodiment, when the amount of heat stored for hot water supply in tank unit 4 is insufficient after automatic bath water pouring is completed, the amount of heat for hot water supply is secured by hot water HW1, and the amount of heat for bath reheating is secured by hot water HW2, thereby improving the convenience of hot water supply and bath reheating.

[0124] FIG. 14A shows a heat storage operation for hot water supply using hot water HW1 when the heat storage amount of the tank unit 4 is insufficient for hot water supply.

[0125] The hot water supply control unit 8 obtains temperature information from the temperature sensors 44-1, ..., 44-5 and determines the amount of heat stored in the tank unit 4. In this case, since the temperature sensor 44-4 detects the temperature of the supply water W, the amount of hot water stored in the tank unit 4 represents the amount of hot water HW1 stored in the tank unit 4 excluding the supply water W up to the level of the temperature sensor 44-4. In this case, the supply water W is taken out of the tank unit 4 and circulated to the HP unit 6, and the hot water HW1 heated to the first set temperature Tc1 is stored in the tank unit 4, and the amount of heat stored necessary for hot water supply is ensured by the amount of hot water HW1 stored.

[0126] If a request for bath reheating occurs during this operation, the hot water supply control unit 8 executes a process to raise the heating temperature of the HP unit 6 to the second set temperature Tc2, raising the temperature to hot water HW2 and discharging the hot water. In this case, since the HP unit 6 is already in a warm-up state, it is possible to quickly raise the temperature to hot water HW2. The process thereafter is the same as the operation or process described in FIG.

[0127] FIG. 14B shows an operation for increasing the amount of heat for hot water supply or for securing the amount of heat for reheating after the amount of heat for hot water supply has been secured.

[0128] After the heat quantity for hot water supply is secured in the tank unit 4 by the hot water HW1, the hot water supply control unit 8 uses this as an opportunity to raise the set temperature from the first set temperature Tc1 to the second set temperature Tc2, that is, to increase the heating capacity of the HP unit 6. Then, the water W is circulated from the tank unit 4 to the HP unit 6, and the hot water HW2 at the second set temperature Tc2 is stored in the tank unit 4, thereby increasing the heat quantity for hot water supply or securing the heat quantity for reheating.

[0129] <Advantages of the Third Embodiment> According to the third embodiment, any one of the following effects can be obtained. (1) The third embodiment has the same effects as the second embodiment.

[0130] (2) Even if the amount of hot water stored in the tank unit 4 decreases, hot water can be supplied based on the desired amount of stored heat, thereby realizing an efficient hot water supply system or method.

[0131] [Fourth embodiment] 15A and 15B show a hot water inlet / outlet portion 68 of a tank unit 4 according to a fourth embodiment. In Fig. 15A and 15B, the same parts as in Fig. 1 are given the same reference numerals.

[0132] The hot water inlet / outlet section 68 includes a hot water inlet pipe 70 and a hot water outlet pipe 72, which are adjacent to each other and inserted into the tank unit 4 from the top. The hot water inlet pipe 70 is a pipe for introducing the hot water HW1 or HW2 into the tank unit 4. The hot water outlet pipe 72 is a pipe used for taking out the hot water HW1 or HW2 from the tank unit 4, and is an example of the outlet port 13-1 described above. The outlet port 13-2 is installed in the tank unit 4 at a lower position, for example, 20 liters from the top.

[0133] A buffer section 74 is provided on the hot water inlet pipe 70 side to buffer the hot water flow of hot water HW1 or hot water HW2 discharged from the hot water inlet pipe 70. A buffer panel 76 is provided on this buffer section 74, opening at the opening of the hot water inlet pipe 70, and a pair of standing walls 78, 79 are provided between this buffer panel 76 and the ceiling section 80 of the tank unit 4. As shown in B of Fig. 15, the standing walls 78, 79 and the buffer panel 76 form a groove section that opens in the front-to-rear direction on the paper surface.

[0134] With this configuration, the buffer section 74 reduces the hot water flow of the hot water HW1 or HW2 introduced into the tank unit 4 from the hot water inlet pipe 70, thereby suppressing the flow of the hot water HW1 or HW2 in the tank unit 4. Here, the flow suppression refers to suppression of the hot water flow, such as the hot water HW1 entering the area of ​​the hot water HW2.

[0135] The hot water extraction pipe 72 protrudes from the ceiling 80 of the tank unit 4 by a shorter length than the hot water introduction pipe 70, and the ceiling 80 of the tank unit 4 is curved outward. Therefore, the hot water HW1 or HW2 is guided to the hot water extraction pipe 72 along the curved surface of the ceiling 80 of the tank unit 4, and the hot water HW1 or HW2 in the tank unit 4 can be gently taken out of the tank unit 4 without disturbing the stratified state.

[0136] <Hot water HW1 outlet direction regulation> 16A and 16B show an example of a portion for regulating the direction of the hot water HW1 from the outlet port 13-2. In Fig. 16, the same parts as those in Fig. 15 are given the same reference numerals.

[0137] As shown in A of Fig. 16, an elliptical opening 82 facing downward is formed at the tip of the extraction port 13-2. This elliptical opening 82 is an example of an extraction direction restricting portion for restricting the extraction direction of the hot water HW1 from the tank unit 4. If such an extraction port 13-2 is disposed below the tank unit 4, only the hot water HW1 can be extracted without affecting the hot water HW2.

[0138] 16B, a cover 86 is formed on the opening 84 at the tip side of the outlet port 13-2 to cover the upper side thereof. This cover 86 is an example of an outlet direction restricting portion for restricting the outlet direction of the hot water HW1 from the tank unit 4. If this cover 86 is disposed below the tank unit 4 with the cover 86 facing downward, it is possible to extract only the hot water HW1 without affecting the hot water HW2.

[0139] <Advantages of the Fourth Embodiment> According to the fourth embodiment, any one of the following effects can be obtained. (1) In the hot water supply system 2, the stratified state of the hot water HW1 and the hot water HW2 in the tank unit 4 is not disturbed, and the regularity of the heat storage form can be maintained.

[0140] (2) Since the stratified state of the hot water HW1 and the hot water HW2 can be maintained, the hot water HW1 or the hot water HW2 can be selectively discharged from the tank unit 4, thereby improving the functions of hot water supply, heat exchange, bath water supply, bath reheating, etc. using the hot water HW1 or the hot water HW2, thereby realizing a highly reliable hot water supply function.

[0141] Other Embodiments The present disclosure includes the following other embodiments. (1) In the first embodiment, a propane refrigerant (R290), which has good thermal efficiency at low temperatures (below 60° C.), is used as refrigerant 56 (FIG. 2), and low-temperature heat storage is the main focus. However, the hot water supply method and system disclosed herein are not limited to propane refrigerant, and other refrigerants may be used.

[0142] (2) In the second embodiment, a single tank unit 4 and HP unit 6 are installed, but there may be multiple tank units 4 and HP units 6, and other heat source devices such as an electric hot water heater or a gas water heater may be used in place of the HP unit 6.

[0143] (3) Although a flow rate sensor is not shown in FIG. 1, a flow rate sensor may be provided to detect the inflow rate of the water W and the supply rate of the hot water HW3.

[0144] (4) In the above embodiment, two types of hot water HW1, HW2 with different temperatures are generated from the supply water W and stored in the tank unit 4. However, three or more types of hot water with different temperatures may be generated and stored in the tank unit 4. The hot water stored in the tank unit 4 is not limited to HW1, HW2.

[0145] As described above, the most preferred embodiment of the present disclosure has been described. The present disclosure is not limited to the above description. Various modifications and changes are possible for those skilled in the art based on the gist of the claims or the disclosure of the embodiments of the invention. It goes without saying that such modifications and changes are included in the scope of the present disclosure. [Industrial Applicability]

[0146] According to the hot water supply system and hot water supply method disclosed herein, hot water at different set temperatures is stored in a hot water storage tank and heat is accumulated, and by using only a heat pump as the heat source unit, in combination with the heat storage in the hot water storage tank, highly convenient hot water supply including bath water supply and bath reheating can be realized.In addition, by providing the hot water storage tank with a first hot water outlet and a second hot water outlet, the first hot water or the second hot water can be selectively extracted, thereby realizing a variety of hot water supply forms. [Explanation of symbols]

[0147] W Water Supply HW1 1st hot water HW2 Second hot water HW3 Third hot water Tc1 1st set temperature Tc2 2nd set temperature 2. Hot water system 4 Hot water tank unit 6. Heat pump unit 8 Hot water supply control unit 10 Remote control device 12 Water supply channel 13-1 First hot water outlet port 13-2 Second hot water outlet port 14 Hot water outlet 15-1, 15-2, 15-3 Three-way valve 16 Distribution valve 18 Flow control valve 20 Bypass Road 22 Hot water supply 24 Pump 26 HP control unit 28-1 1st circulation route 28-2 Second circulation route 28-3 Third circulation route 28-4 4th circulation route 28-5 5th circulation route 28-6 6th circulation route 28-7 7th circulation route 28-8 8th circulation route 30 Reheating circulation route 36 Heat exchanger 38 Bath 40 Circulation port 42 Pump 44-1, 44-2, 44-3, 44-4, 44-5, 44-6, 44-7, 44-8, 44-9, 44-10, 44-11, 44-12, 44-13 Temperature Sensors 46 Refrigerant circuit 48-1, 48-2 heat exchanger 50 Expansion valve 52 Air heat exchanger 54 Compressor 56 Refrigerants 58 Control Systems 60 processors 62 Storage section 64 Input / output section (I / O) 66 Communications Department 68 Hot water inlet / outlet 70 Hot water introduction pipe 72 Hot water outlet pipe 74 Buffer section 76 Buffer Panel 78, 79 Standing Wall 80 Ceiling 82 Oval opening 84 Opening 86 Cover

Claims

1. A heat source machine that heats supply water to obtain at least a first hot water having a first set temperature and / or a second hot water having a second set temperature higher than the first set temperature; a hot water storage tank for storing the first hot water and storing the second hot water above the first hot water, the hot water storage tank including a first hot water outlet for taking out the first hot water or the second hot water, and a second hot water outlet for taking out the first hot water; a hot water outlet path for discharging the first hot water or the second hot water from the first hot water outlet or discharging the first hot water from the second hot water outlet at the time of discharging hot water; a valve interposed between the first hot water outlet and the second hot water outlet and the hot water outlet path, for adjusting an opening degree of the first hot water outlet side and / or an opening degree of the second hot water outlet side, and for discharging the first hot water and / or the second hot water to the hot water outlet path; , including a hot water system.

2. The hot water supply system according to claim 1 , wherein a temperature difference between the first hot water and the second hot water is 10° C. or more.

3. The hot water supply system according to claim 1 , wherein the second hot water outlet is provided outside a hot water storage area in which the second hot water is stored, or is provided within a hot water storage area in which the first hot water is stored.

4. a plurality of temperature sensors for detecting temperature information of the first hot water and / or the second hot water stored in the hot water storage tank; a control unit that determines the first hot water and / or the second hot water based on the temperature information, controls the switching or opening of the valve based on the determination result, and causes the first hot water to be discharged from the second hot water outlet to the hot water outlet; The hot water system of claim 1 .

5. a hot water supply passage for supplying third hot water obtained by mixing the first hot water or the second hot water with the supply water; A regulation valve that regulates the amount of the third hot water supplied; a distribution valve that distributes the supply water to the hot water supply passage and the hot water storage tank; A temperature sensor for detecting temperature information of the third hot water; The hot water supply system according to claim 1 or 4, further comprising: a control unit that acquires the temperature information and controls an opening degree of the regulating valve and / or the distributing valve to control the third hot water to a hot water supply setting temperature.

6. The hot water supply system according to claim 1 or 4, wherein the hot water storage tank includes a buffer section that buffers a hot water flow in the hot water storage tank when hot water is introduced.

7. The hot water supply system according to claim 1 or 4, wherein the second hot water outlet includes an outlet direction regulating portion for extracting the first hot water, and extracts the first hot water located on a lower layer side of the hot water storage tank.

8. A step in which a heat source unit heats the supply water to at least first hot water having a first set temperature and / or second hot water having a second set temperature higher than the first set temperature; storing the first hot water in a hot water storage tank and storing the second hot water above the first hot water; a control unit, when discharging hot water, adjusting the opening degree of the first hot water outlet side and the second hot water outlet side of the valve, and discharging the first hot water and / or the second hot water from the first hot water outlet to the hot water outlet passage, or discharging the first hot water from the second hot water outlet to the hot water outlet passage; A hot water supply method comprising:

9. The hot water supply method according to claim 8 , wherein a temperature difference between the first hot water and the second hot water is 10° C. or more.

10. A step of detecting temperature information representing the first hot water and / or the second hot water by a temperature sensor; A step in which a control unit acquires the temperature information, determines whether the first hot water and / or the second hot water is stored, and controls the switching or opening of the valve based on the determination result, thereby causing the first hot water to be discharged from the second hot water outlet to the hot water outlet path; The hot water supply method according to claim 8, comprising:

11. The hot water supply method according to claim 8 or 10, further comprising a step of exchanging heat between the second hot water discharged from the hot water storage tank and bath water.

12. a step of adjusting a third hot water obtained by mixing the first hot water discharged from the second hot water outlet with supply water to a hot water outlet setting temperature and supplying the third hot water; During hot water supply, the supply water is heated to the second hot water by the heat source device and stored in the hot water storage tank; The hot water supply method according to claim 8 or claim 10, comprising:

Images