JP2017194203A - Heat storage system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat storage system capable of executing operations of various modes with a constitution reduced in the number of switch valves.SOLUTION: A storage type hot water supply system 1 includes a hot water storage tank 10, a heat pump unit 60, a first four-way valve 31, a use-side heat exchanger 22, and a circulation pump 21. A first flow channel configuration in which a low-temperature pipe 40 connecting a lower portion of the hot water storage tank 10 and the first four-way valve 31 is connected to a heat pump inlet pipe 41 through the first four-way valve 31, a second flow channel configuration in which a high-temperature pipe 48 connecting an upper portion of the hot water storage tank 10 and the first four-way valve 31 is connected to a bypass passage 45 through the first four-way valve 31, and a third flow channel configuration in which the low-temperature pipe 40 is connected to the bypass passage 45 through the first four-way valve 31, can be selected.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a heat storage system.

  The conventional hot water storage type hot water supply system disclosed in the following Patent Document 1 can perform a heat recovery operation for recovering waste heat of bathtub water in a hot water storage tank, in addition to a boiling operation and a reheating operation.

JP2013-245919A

  The system of Patent Document 1 has an advantage that the number of pumps can be reduced because the circulation pump (21) can be commonly used in any of the boiling operation, the reheating operation, and the heat recovery operation. However, there is a problem that the product cost is increased in that two switching valves, that is, a three-way valve (31) and a three-way valve (33) are required on the upstream side of the circulation pump (21).

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a heat storage system capable of performing various modes of operation with a configuration having a small number of switching valves.

  A heat storage system according to the present invention includes a heat storage tank that stores a heat medium, a heating unit that heats the heat medium, a four-way valve, and a use-side heat exchanger that exchanges heat between the heat medium and the use-side medium. A low-temperature pipe connecting between the circulation pump, the lower part of the heat storage tank and the four-way valve, a high-temperature pipe connecting between the upper part of the heat storage tank and the four-way valve, and heating means from the four-way valve via the circulation pump An inlet-side path that leads to the inlet of the heater, an outlet-side path that leads to the outlet of the heating means, a bypass path that leads from the four-way valve to the upstream side of the circulation pump of the inlet-side path via the user-side heat exchanger, and a four-way valve A first flow path configuration in which the low temperature piping communicates with the inlet side path via the four-way valve, and a second flow path configuration in which the high temperature piping communicates with the bypass path via the four-way valve; The third flow path where the low-temperature pipe communicates with the bypass path via the four-way valve On purpose, it is those that are can be selected.

  According to the heat storage system of the present invention, it is possible to execute various modes of operation with a configuration having a small number of switching valves.

It is a figure which shows the hot water storage type hot-water supply system of Embodiment 1. FIG. FIG. 3 is a circuit configuration diagram in a standby state in the hot water storage type hot water supply system of the first embodiment. FIG. 3 is a circuit configuration diagram at the time of a single heat storage operation in the hot water storage type hot water supply system of the first embodiment. FIG. 3 is a circuit configuration diagram of a bath water replenishment single operation using hot water in the hot water storage type hot water supply system of the first embodiment. FIG. 3 is a circuit configuration diagram at the time of bathtub water waste heat recovery operation in the hot water storage type hot water supply system of the first embodiment. It is a circuit block diagram when the hot water storage type hot water supply system of Embodiment 1 performs a thermal storage operation and a bath function operation simultaneously. FIG. 3 is a circuit configuration diagram in the freeze prevention operation of the heat pump pipe in the hot water storage type hot water supply system of the first embodiment. It is a circuit block diagram at the time of the heat pump piping freezing prevention operation using the waste heat of the bathtub water in the hot water storage type hot water supply system of Embodiment 1. FIG. It is a circuit block diagram at the time of the heat storage driving | operation using the waste heat of the bathtub water in the hot water storage type hot-water supply system of Embodiment 1. FIG. FIG. 3 is a circuit configuration diagram at the time of heat pump piping freezing prevention operation using high-temperature water in a hot water storage tank in the hot water storage type hot water supply system of the first embodiment.

  Hereinafter, embodiments will be described with reference to the drawings. Elements common to the drawings are denoted by the same reference numerals, and redundant description is simplified or omitted.

Embodiment 1 FIG.
FIG. 1 is a diagram showing a hot water storage type hot water supply system 1 according to a first embodiment. As shown in FIG. 1, the hot water storage type hot water supply system 1 according to the first embodiment includes a hot water storage tank unit 20, a heat pump unit 60, a control device 70, and a remote controller 80. The hot water storage type hot water supply system 1 is an example of a heat storage system.

  The hot water storage tank unit 20 and the heat pump unit 60 are connected via a heat pump inlet pipe 41, a heat pump outlet pipe 42, and electrical wiring (not shown). In the present embodiment, a control device 70 is built in the hot water storage tank unit 20. Operations of various valves, pumps and the like provided in the hot water storage tank unit 20 and the heat pump unit 60 are controlled by a control device 70 electrically connected thereto. Hereinafter, each component of the hot water storage type hot water supply system 1 will be described.

  The heat pump unit 60 is an example of a heating unit that heats the heat medium. The heat medium in the present embodiment is water. The heat medium may be a liquid heat medium other than water, such as an aqueous calcium chloride solution, an aqueous ethylene glycol solution, or alcohol. The heating means is not limited to the heat pump unit 60. The heating means may be a combustion heating device that heats with the combustion heat of a fuel such as gas, kerosene, heavy oil, or coal. The heating means may be a device that heats the heat medium by solar heat.

  The heat pump unit 60 includes a refrigerant circuit in which a compressor 61, a water-refrigerant heat exchanger 62, an expansion valve 63, and an air heat exchanger 64 are annularly connected by a refrigerant circulation pipe 65. The heat pump unit 60 operates the refrigeration cycle, that is, the heat pump cycle by circulating the refrigerant in the refrigerant circuit. In the water-refrigerant heat exchanger 62, water is heated by exchanging heat between the high-temperature and high-pressure refrigerant compressed by the compressor 61 and water.

  The HP outlet side temperature sensor 66 installed in the heat pump outlet pipe 42 is an example of a temperature sensor that detects the temperature of high-temperature water heated by the water-refrigerant heat exchanger 62. In order to obtain high-temperature water with the heat pump unit 60, it is preferable that the heat pump cycle is operated at a pressure exceeding the critical pressure using carbon dioxide as a refrigerant.

  The hot water storage tank unit 20 incorporates the following various parts and piping. The hot water storage tank 10 stores hot water. The hot water storage tank 10 is an example of a heat storage tank that stores a heat medium. A water supply pipe 2 for supplying low-temperature water from a water source such as a water supply communicates with the lower part of the hot water storage tank 10. A hot water supply pipe 3 and a tank upper pipe 43 communicate with the upper part of the hot water storage tank 10. The hot water supply pipe 3 is a pipe for sending hot water to a hot water supply terminal outside the hot water storage type hot water supply system 1. In the configuration shown in the figure, the hot water supply pipe 3 and the tank upper pipe 43 merge and are connected to the upper part of the hot water storage tank 10. Not limited to this configuration, the hot water supply pipe 3 and the tank upper pipe 43 may be separately connected to the upper part of the hot water storage tank 10.

  The hot water storage type hot water supply system 1 can execute a heat storage operation. The heat storage operation is an operation in which high-temperature water heated using the heat pump unit 60 is accumulated in the hot water storage tank 10. At the time of heat storage operation, it is as follows. Hot water heated using the heat pump unit 60 flows into the hot water storage tank 10 from the tank upper pipe 43. A low temperature pipe 40 communicates with the lower part of the hot water storage tank 10. The water stored in the lower part of the hot water storage tank 10 is sent to the heat pump unit 60 through the low temperature pipe 40. Inside the hot water storage tank 10, a temperature stratification is formed in which the upper side is hot and the lower side is cold due to the difference in water density depending on the temperature.

  On the surface of the hot water storage tank 10, a plurality of hot water storage temperature sensors 11, 12, 13 are attached at different height positions. By detecting the temperature distribution of the hot water in the hot water storage tank 10 in the vertical direction by the hot water storage temperature sensors 11, 12, and 13, the amount of hot water stored and the amount of heat stored in the hot water storage tank 10 can be calculated. The control device 70 controls the start and stop of the heat storage operation based on the amount of stored hot water or the amount of stored heat.

  A circulation pump 21 and a use side heat exchanger 22 are built in the hot water storage tank unit 20. The circulation pump 21 is a pump for circulating hot water through various pipes to be described later in the hot water storage tank unit 20. The usage-side heat exchanger 22 exchanges heat between the hot water supplied from the hot water storage tank 10 or the heat pump unit 60 and the secondary-side usage-side medium, thereby heating the usage-side medium. It is an exchanger.

  The usage-side medium may be, for example, bathtub water led from the bathtub 50 or a heating heat medium. In the first embodiment, as a secondary side configuration of the use side heat exchanger 22, a bathtub water circulation circuit 51 that circulates bathtub water led from the bathtub 50 will be described as an example. The use side heat exchanger 22 is installed in the middle of the bathtub water circulation circuit 51. In the middle of the bathtub water circulation circuit 51, a bathtub water circulation pump 52 for circulating the bathtub water and a bathtub water temperature sensor 53 for detecting the temperature of the bathtub water discharged from the bathtub 50 are installed. The bathtub water circulation pump 52 is an example of a second circulation pump that circulates the use-side medium.

  Next, the valves and piping provided in the hot water storage tank unit 20 will be described. The hot water storage tank unit 20 includes a first four-way valve 31 and a second four-way valve 32. The first four-way valve 31 is a flow path switching means having an a port and a b port that are inlets through which hot water flows and a c port and a d port that are outlets through which hot water flows out. The first four-way valve 31 is configured to be able to switch the hot water path so that hot water flows in from either the a port or the b port and flows out of either the c port or the d port. That is, the first four-way valve 31 is configured to be able to switch the flow path form among four paths, that is, the a-c path, the a-d path, the bc path, and the b-d path.

  The second four-way valve 32 is a flow path switching means having a b port and a c port that are inlets for hot water to flow in, and an a port and a d port that are outlets for hot water to flow out. The second four-way valve 32 is configured to be able to switch the flow path form among three paths, that is, an ab path, an ac path, and a cd path. The second four-way valve 32 may be configured to be able to switch the flow path form among four paths, that is, an ab path, an ac path, a cd path, and a dd path.

  The low-temperature pipe 40 is a flow path that connects between the lower part of the hot water storage tank 10 and the a port of the first four-way valve 31. The heat pump inlet pipe 41 is a flow path that leads from the c port of the first four-way valve 31 to the inlet of the heat pump unit 60 via the circulation pump 21. That is, the heat pump inlet pipe 41 includes a flow path that connects the c port of the first four-way valve 31 and the inlet of the circulation pump 21, and a flow path that connects the outlet of the circulation pump 21 and the inlet of the heat pump unit 60. The heat pump outlet pipe 42 is a flow path that connects between the outlet of the heat pump unit 60 and the c port of the second four-way valve 32. The heat pump inlet pipe 41 is an example of an inlet-side path that does not pass through the use-side heat exchanger 22. The heat pump outlet pipe 42 is an example of an outlet side path.

  The tank upper pipe 43 is a flow path that connects between the d port of the second four-way valve 32 and the upper part of the hot water storage tank 10. The tank return pipe 44 is a flow path that connects between the a port of the second four-way valve 32 and the return port 14 of the hot water storage tank 10. The position of the return port 14 is at a height between the upper part and the lower part of the hot water storage tank 10. The return port 14 is located closer to the lower end than the upper end of the hot water storage tank 10.

  The bypass path 45 is a flow path that leads from the d port of the first four-way valve 31 to the branch portion 33 via the use side heat exchanger 22. The branch portion 33 is on the upstream side of the circulation pump 21 of the heat pump inlet pipe 41. The hot water that has passed through the bypass path 45 and the use side heat exchanger 22 joins the heat pump inlet pipe 41 at the branch portion 33 and is sucked into the circulation pump 21.

  One end of the high-temperature pipe 48 communicates with the upper part of the hot water storage tank 10. The other end of the high temperature pipe 48 is connected to the b port of the first four-way valve 31. The bypass pipe 47 is a flow path that connects between the branch portion 34 and the b port of the second four-way valve 32. The branch portion 34 is on the downstream side of the circulation pump 21 of the heat pump inlet pipe 41.

  The downstream side of the hot water supply pipe 3 is connected to hot water supply terminals such as a faucet, a shower, and a bathtub 50, for example. Hot water stored in the hot water storage tank 10 can be supplied to the hot water supply terminal via the hot water supply pipe 3. When hot water in the hot water storage tank 10 flows out into the hot water supply pipe 3, low temperature water flows into the hot water storage tank 10 from the water supply pipe 2, so that the hot water storage tank 10 is maintained in a full state. A mixing valve (not shown) for adjusting the hot water supply temperature by mixing low temperature water from a water source may be provided in the middle of the hot water supply pipe 3.

  In the hot water storage type hot water supply system 1 according to the first embodiment, the control device 70 controls the first four-way valve 31 in accordance with the states shown in FIGS. The hot water flow path in the hot water storage tank unit 20 is switched between the four flow path forms of the form, the third flow path form, and the fourth flow path form.

  The “first flow path configuration” that can be selected by the first four-way valve 31 is a flow path configuration in which the low-temperature pipe 40 communicates with the heat pump inlet pipe 41 via the a port and the c port of the first four-way valve 31. is there. The “second flow path configuration” that can be selected by the first four-way valve 31 is a flow path configuration in which the high-temperature pipe 48 communicates with the bypass path 45 through the b port and the d port of the first four-way valve 31. . The “third flow path configuration” that can be selected by the first four-way valve 31 is a flow channel configuration in which the low-temperature pipe 40 communicates with the bypass path 45 via the a port and the d port of the first four-way valve 31. . The “fourth flow path configuration” that can be selected by the first four-way valve 31 is a flow path configuration in which the high-temperature pipe 48 communicates with the heat pump inlet pipe 41 via the b port and the c port of the first four-way valve 31. is there.

  In the hot water storage hot water supply system 1 according to the first embodiment, the control device 70 controls the second four-way valve 32 in accordance with the states shown in FIGS. The hot water flow path in the hot water storage tank unit 20 is switched between the three flow path forms of the form and the third flow path form.

  The “first flow path configuration” that can be selected by the second four-way valve 32 is a flow path configuration in which the heat pump outlet pipe 42 communicates with the tank upper pipe 43 via the c port and the d port of the second four-way valve 32. It is. The “second flow path configuration” that can be selected by the second four-way valve 32 is a flow path configuration in which the heat pump outlet pipe 42 communicates with the tank return pipe 44 via the c port and a port of the second four-way valve 32. It is. The “third flow path configuration” that can be selected by the second four-way valve 32 is a flow path configuration in which the bypass pipe 47 communicates with the tank return pipe 44 via the a port and the b port of the second four-way valve 32. is there.

  The second four-way valve 32 can further select a “fourth flow path configuration” which is a flow path configuration in which the bypass pipe 47 communicates with the tank upper pipe 43 via the b port and the d port of the second four-way valve 32. May be configured.

  FIG. 2 is a circuit configuration diagram in a standby state in the hot water storage type hot water supply system 1 according to the first embodiment. This standby state is a state in which any operation such as a heat storage operation and a bath water retreat operation is not performed. In the standby state: All of circulation pump 21, heat pump unit 60, and bathtub water circulation pump 52 are in a stopped state. The first four-way valve 31 is controlled so as to be in the first flow path form. The second four-way valve 32 is controlled to be in the second flow path form.

  FIG. 3 is a circuit configuration diagram at the time of a single heat storage operation in the hot water storage type hot water supply system 1 of the first embodiment. The single heat storage operation is an operation in which the heat storage operation for accumulating high-temperature water heated by the heat pump unit 60 in the hot water storage tank 10 is performed independently.

  In the case of single operation of heat storage, it is as follows. Circulation pump 21 and heat pump unit 60 are operated. The first four-way valve 31 is controlled so as to be in the first flow path form. The second four-way valve 32 is controlled to be in the first flow path form.

  In heat storage single operation, water circulates in the following circuit. Water flowing out from the lower part of the hot water storage tank 10 is led to the heat pump unit 60 via the low temperature pipe 40, the first four-way valve 31, the heat pump inlet pipe 41 and the circulation pump 21, and in the water-refrigerant heat exchanger 62. Heated. The heated high temperature water flows into the upper part of the hot water storage tank 10 via the heat pump outlet pipe 42, the second four-way valve 32 and the tank upper pipe 43. By executing such a single heat storage operation, high-temperature water is stored in the hot water storage tank 10 from the upper layer portion, and the high-temperature water layer gradually becomes thicker downward.

  FIG. 4 is a circuit configuration diagram of a bath water replenishment single operation using hot water in the hot water storage type hot water supply system 1 of the first embodiment. The bath water pursuit single operation using the hot water storage is an operation in which the hot water stored in the hot water storage tank 10 is used to independently heat the bath water in the use side heat exchanger 22.

  In the case of independent operation of bathing water using a hot water storage, the operation is as follows. Circulation pump 21 and bathtub water circulation pump 52 are operated. The heat pump unit 60 stops operating. The first four-way valve 31 is controlled so as to be in the second flow path form. The second four-way valve 32 is controlled to be in the third flow path configuration.

  In a bath water replenishment single operation using hot water storage, water circulates in the following circuit. The high temperature water flowing out from the upper part of the hot water storage tank 10 is guided to the use side heat exchanger 22 via the high temperature pipe 48, the first four-way valve 31, and the bypass path 45. The hot water is deprived of heat by the bath water in the use side heat exchanger 22, so that the temperature is lowered to become medium hot water. This medium-temperature water is supplied from the use side heat exchanger 22 via the branch part 33, the circulation pump 21, the heat pump inlet pipe 41, the branch part 34, the bypass pipe 47, the second four-way valve 32, and the tank return pipe 44. Then, it flows into the hot water storage tank 10 from the return port 14. In the hot water storage tank 10, the high-temperature water layer is gradually thinned.

  In the bathtub water pursuit single operation using hot water storage, the bathtub water circulates in the bathtub water circulation circuit 51 and the bathtub water heated by the use side heat exchanger 22 returns to the bathtub 50, so that the hot water stretched in the bathtub 50 is supplied. Is warmed.

  FIG. 5 is a circuit configuration diagram in the bathtub water waste heat recovery operation in the hot water storage type hot water supply system 1 of the first embodiment. The bathtub water waste heat recovery operation is an operation of recovering the remaining heat of the bathtub 50, that is, the waste heat of the bathtub water, into the hot water storage tank 10.

  At the time of bathtub water waste heat recovery operation, it is as follows. Circulation pump 21 and bathtub water circulation pump 52 are operated. Bathtub water circulates in the bathtub water circulation circuit 51. The heat pump unit 60 stops operating. The first four-way valve 31 is controlled so as to be in the third flow path configuration. The second four-way valve 32 is controlled to be in the third flow path configuration.

  In the bathtub water waste heat recovery operation, water circulates in the following circuit. Low temperature water (for example, 10 ° C.) flowing out from the lower part of the hot water storage tank 10 is guided to the use side heat exchanger 22 via the low temperature pipe 40, the first four-way valve 31, and the bypass path 45. This low temperature water receives the heat of bathtub water (for example, 40 degreeC) with the use side heat exchanger 22, and temperature rises and becomes medium temperature water (for example, 30 degreeC). This medium-temperature water is supplied from the use side heat exchanger 22 via the branch part 33, the circulation pump 21, the heat pump inlet pipe 41, the branch part 34, the bypass pipe 47, the second four-way valve 32, and the tank return pipe 44. Then, it flows into the hot water storage tank 10 from the return port 14 and is stored in the hot water storage tank 10.

  The control device 70 may determine whether or not to execute the bathtub water waste heat recovery operation state, that is, whether or not the waste water recovery of the bathtub water is feasible. After operating the bathtub water circulation pump 52, the control device 70 performs the bathtub water waste heat recovery operation when a water flow detection sensor (not shown) installed in the bathtub water circulation circuit 51 detects the presence of a water flow within a predetermined time. You may start. Further, the temperature detected by the bathtub water temperature sensor 53 when a time (for example, 30 seconds) has elapsed until the bathtub water in the bathtub 50 reaches the bathtub water temperature sensor 53 by operating the bathtub water circulation pump 52 is a predetermined value. When it is (for example, 35 ° C.) or higher, the bath water waste heat recovery operation may be started. Alternatively, the bath water waste heat recovery operation may be started when the detected temperature is higher than the water temperature in the lower part of the hot water storage tank 10 detected by the hot water storage temperature sensor 12.

  In the present embodiment, the following effects can be obtained. The bath water waste heat recovery operation can be executed using the component configuration used for the heat storage operation and the bath water replenishment operation which are the basic functions of the hot water storage type hot water supply system 1. That is, it is not necessary to add a new part such as a heat exchanger or a switching valve only for performing the bath water waste heat recovery operation. Recover waste water from bathtub water with high efficiency with a configuration having a smaller number of switching valves than before, that is, a configuration in which the switching valve on the upstream side of the circulation pump 21 is only one of the first four-way valves 31. Is possible.

  Next, the bath function operation during the heat storage operation will be described with reference to FIG. The bath function operation is a state in which the bathtub water circulation pump 52 is operated. The bath function operation includes, for example, at least one of bath water presence / absence detection operation, bath pipe freezing prevention operation, and bath water temperature detection operation. The bathtub water presence / absence detection operation is a state in which the bathtub water circulation pump 52 is operated in order to detect the presence / absence of bathtub water in the bathtub 50 by a water flow detection sensor (not shown) installed in the bathtub water circulation circuit 51. The piping forming the bathtub water circulation circuit 51 often passes outdoors at least partially. For this reason, the water in the piping of the bathtub water circulation circuit 51 may freeze in winter. The bath piping freezing prevention operation is a state in which the bathtub water circulation pump 52 is operated for the purpose of preventing the water in the piping of the bathtub water circulation circuit 51 from freezing. The bathtub water temperature detection operation is a state in which the bathtub water circulation pump 52 is operated for the purpose of drawing the bathtub water in the bathtub 50 to the bathtub water temperature sensor 53 in order to check the temperature of the bathtub water in the bathtub 50. The bath water temperature detection operation is executed, for example, during the automatic bath operation that automatically keeps the temperature of the bath water in the bath 50.

  The control device 70 may control the heat storage operation based on the amount of stored hot water or the amount of heat stored in the hot water storage tank 10 and information obtained by learning the past usage record of the user. Alternatively, the control device 70 may perform the heat storage operation in the late-night time zone (for example, 23:00 to 7:00 on the next day) until the hot water storage tank 10 is fully hot. At this time, the heat storage operation is performed regardless of the bath function.

  FIG. 6 is a circuit configuration diagram when the hot water storage type hot water supply system 1 according to the first embodiment simultaneously executes the heat storage operation and the bath function operation. The circuit of the heat storage operation of FIG. 6 is the same as the circuit of the heat storage single operation of FIG. The bath water circulation pump 52 operates when the bath function operation (for example, bath water presence / absence detection operation, bath pipe freezing prevention operation, or bath water temperature detection operation) is required during the execution of the single heat storage operation of FIG. Is started, the state shown in FIG. 6 is obtained. In the present embodiment, since the circuit in the heat storage isolated operation is a circuit that does not pass through the use-side heat exchanger 22, the heat storage operation and the bath function can be performed without affecting the heat storage operation and the bath function operation. Operation can be performed simultaneously.

  FIG. 7 is a circuit configuration diagram in the freeze prevention operation of the heat pump piping in the hot water storage type hot water supply system 1 of the first embodiment. The heat pump inlet pipe 41 and the heat pump outlet pipe 42 often pass at least partially outdoors. For this reason, the water in the heat pump inlet pipe 41 and the heat pump outlet pipe 42 may freeze in winter. The freeze prevention operation of the heat pump pipe is an operation aimed at preventing the water in the heat pump inlet pipe 41 and the heat pump outlet pipe 42 from freezing.

  At the time of the freeze prevention operation of the heat pump pipe, it is as follows. The circulation pump 21 is operated. The heat pump unit 60 may not be operated. The first four-way valve 31 is controlled so as to be in the first flow path form. The second four-way valve 32 is controlled to be in the second flow path form.

  The control device 70 may execute the freeze prevention operation of the heat pump pipe when an outside air temperature sensor (not shown) that detects the outdoor temperature detects a temperature lower than a predetermined temperature (for example, 5 ° C. or lower).

  In the freeze prevention operation of the heat pump pipe, water circulates in the following circuit. Water flowing out from the lower part of the hot water storage tank 10 is led to the water-refrigerant heat exchanger 62 of the heat pump unit 60 via the low temperature pipe 40, the first four-way valve 31, the heat pump inlet pipe 41 and the circulation pump 21. Water that has passed through the water-refrigerant heat exchanger 62 flows into the hot water storage tank 10 from the return port 14 via the heat pump outlet pipe 42, the second four-way valve 32, and the tank return pipe 44.

  When the water temperature in the pipe detected by, for example, the HP outlet side temperature sensor 66 is lower than a predetermined temperature (for example, 3 ° C.) during the operation of the freeze prevention operation of the heat pump pipe, the control device 70 causes the heat pump unit 60 to By starting and heating water in the water-refrigerant heat exchanger 62, a temperature drop in the pipe may be prevented.

  Next, the heat pump piping freezing prevention operation using the waste heat of bathtub water will be described with reference to FIG. The control device 70 may determine whether or not the heat pump pipe freezing prevention operation using the waste heat of the bathtub water shown in FIG. 8 can be performed as follows. The control device 70 operates the bathtub water circulation pump 52 and detects the temperature of the bathtub water in the bathtub 50 with the bathtub water temperature sensor 53. When the temperature of the bathtub water in the bathtub 50 (for example, 40 ° C.) is higher than the water temperature in the heat pump inlet pipe 41 and the heat pump outlet pipe 42, for example, the water temperature detected by the HP outlet side temperature sensor 66 (for example, 5 ° C.) The control device 70 may determine that the heat pump piping freezing prevention operation using the waste heat of the bath water is executable. Otherwise, the control device 70 may determine that the heat pump pipe freezing prevention operation using the waste heat of the bath water is not executable.

  FIG. 8 is a circuit configuration diagram at the time of heat pump piping freezing prevention operation using waste heat of bathtub water in the hot water storage type hot water supply system 1 of the first embodiment. At the time of heat pump piping freezing prevention operation using the waste heat of bathtub water, it becomes as follows. Circulation pump 21 and bathtub water circulation pump 52 are operated. Bathtub water circulates in the bathtub water circulation circuit 51. The heat pump unit 60 may not be operated. The first four-way valve 31 is controlled so as to be in the third flow path configuration. The second four-way valve 32 is controlled to be in the second flow path form.

  In the heat pump piping freezing prevention operation using the waste heat of bathtub water, water circulates in the following circuits. The low temperature water flowing out from the lower part of the hot water storage tank 10 is guided to the use side heat exchanger 22 via the low temperature pipe 40, the first four-way valve 31, and the bypass path 45. This low-temperature water receives the heat of the bath water in the use side heat exchanger 22, so that the temperature rises and becomes medium-temperature water. This medium-temperature water is led from the use side heat exchanger 22 to the water-refrigerant heat exchanger 62 of the heat pump unit 60 via the branch portion 33, the circulation pump 21, and the heat pump inlet pipe 41. Water that has passed through the water-refrigerant heat exchanger 62 flows into the hot water storage tank 10 from the return port 14 via the heat pump outlet pipe 42, the second four-way valve 32, and the tank return pipe 44.

  When it is determined that the heat pump pipe freezing prevention operation using the waste water of the bath water is feasible, the control device 70 executes the freezing prevention operation of FIG. 8 and the heat pump pipe freezing prevention operation using the waste water of the bath water. 7 may be executed when the freeze prevention operation is determined to be impossible. When it is determined that the heat pump pipe freezing prevention operation using the waste heat of the bath water is executable during the freeze prevention operation of FIG. 7, the control device 70 causes the first four-way valve 31 to pass through the first flow path. While switching from the form to the third flow path form, the operation of the bathtub water circulation pump 52 may be started to shift to the freeze prevention operation of FIG.

  If it is this Embodiment, it will become possible to perform the freeze prevention driving | operation of heat pump piping using the waste heat of bathtub water, and effective use of thermal energy will be attained.

  Next, the heat storage operation using the waste heat of bathtub water is demonstrated using FIG. The control device 70 may determine whether or not the heat storage operation using the waste heat of the bath water shown in FIG. 9 can be executed during the heat storage single operation of FIG. 3 as follows. The control device 70 operates the bathtub water circulation pump 52 and detects the temperature of the bathtub water in the bathtub 50 with the bathtub water temperature sensor 53. When the temperature of the bathtub water in the bathtub 50 is higher than the water temperature in the lower part of the hot water storage tank 10 detected by the hot water storage temperature sensor 12, the control device 70 can execute the heat storage operation using the waste heat of the bathtub water. May be determined. When that is not right, the control apparatus 70 may determine with the heat storage driving | operation using the waste heat of bathtub water being infeasible.

  FIG. 9 is a circuit configuration diagram in a heat storage operation using waste heat of bathtub water in the hot water storage type hot water supply system 1 of the first embodiment. At the time of the heat storage operation using the waste heat of the bath water, it is as follows. Circulation pump 21, bathtub water circulation pump 52, and heat pump unit 60 are operated. Bathtub water circulates in the bathtub water circulation circuit 51. The first four-way valve 31 is controlled so as to be in the third flow path configuration. The second four-way valve 32 is controlled to be in the first flow path form.

  When it is determined that the heat storage operation using the waste heat of the bath water is feasible during the execution of the single heat storage operation of FIG. 3, the control device 70 moves the first four-way valve 31 from the first flow path configuration to the first. You may transfer to the heat storage operation | movement using the waste heat of the bathtub water of FIG. 9 by switching to a 3 flow path form and starting the driving | operation of the bathtub water circulation pump 52. FIG.

  In the heat storage operation using the waste heat of bathtub water, water circulates in the following circuit. The low temperature water flowing out from the lower part of the hot water storage tank 10 is guided to the use side heat exchanger 22 via the low temperature pipe 40, the first four-way valve 31, and the bypass path 45. This low-temperature water receives the heat of the bath water in the use side heat exchanger 22, so that the temperature rises and becomes medium-temperature water. This medium-temperature water is led from the use side heat exchanger 22 to the water-refrigerant heat exchanger 62 of the heat pump unit 60 via the branch portion 33, the circulation pump 21, and the heat pump inlet pipe 41. The medium temperature water is further heated in the water-refrigerant heat exchanger 62 to become high temperature water. The hot water flows into the upper part of the hot water storage tank 10 via the heat pump outlet pipe 42, the second four-way valve 32 and the tank upper pipe 43. By executing the heat storage operation using the waste heat of the bathtub water, high-temperature water is stored from the upper layer inside the hot water storage tank 10, and the high-temperature water layer is gradually thickened downward. Become.

  If it is this Embodiment, the following effects are acquired by performing the thermal storage driving | operation using the waste heat of bathtub water. It becomes possible to preheat the water supplied to the heat pump unit 60 using the waste heat of the bath water. As a result, the power consumption of the heat pump unit 60 can be reduced, and energy can be used effectively.

  Next, the heat pump piping freezing prevention operation using the high temperature water of the hot water storage tank 10 will be described with reference to FIG. FIG. 10 is a circuit configuration diagram of the heat pump piping freezing prevention operation using the high temperature water in the hot water storage tank 10 in the hot water storage type hot water supply system 1 of the first embodiment. At the time of the heat pump piping freezing prevention operation using the high temperature water in the hot water storage tank 10, the operation is as follows. The circulation pump 21 is operated. The bathtub water circulation pump 52 and the heat pump unit 60 are stopped. The first four-way valve 31 is controlled so as to be in the fourth flow path configuration. The second four-way valve 32 is controlled to be in the second flow path form.

  In the heat pump pipe freezing prevention operation using the hot water in the hot water storage tank 10, the water circulates in the following circuit. Hot water flowing out from the upper part of the hot water storage tank 10 is led to the water-refrigerant heat exchanger 62 of the heat pump unit 60 via the high temperature pipe 48, the first four-way valve 31, the heat pump inlet pipe 41, and the circulation pump 21. It is burned. Water that has passed through the water-refrigerant heat exchanger 62 flows into the hot water storage tank 10 from the return port 14 via the heat pump outlet pipe 42, the second four-way valve 32, and the tank return pipe 44.

  If it is this Embodiment, the following effects are acquired by performing the heat pump piping freezing prevention operation using the high temperature water of the hot water storage tank 10. FIG. Freezing of the heat pump inlet pipe 41 and the heat pump outlet pipe 42 can be reliably prevented without operating the heat pump unit 60. Since the operation time and the number of start / stop times of the heat pump unit 60 can be reduced, the life of the heat pump unit 60 can be extended.

  The control device 70 determines whether or not there is a risk of freezing during the execution of the heat pump pipe freezing prevention operation of FIG. 7, that is, the heat pump pipe freezing prevention operation using the high-temperature water of the hot water storage tank 10 of FIG. It may be determined whether or not is necessary. The temperature of water flowing through the heat pump inlet pipe 41 and the heat pump outlet pipe 42 is detected by the HP outlet side temperature sensor 66. When the detected temperature of the HP outlet side temperature sensor 66 is a predetermined temperature or lower (for example, 5 ° C. or lower), the control device 70 may determine that the heat pump pipe freezing prevention operation using the high-temperature water in the hot water storage tank 10 is necessary. . The control device 70 switches the first four-way valve 31 from the first flow path configuration to the fourth flow path configuration, so that the heat pump using the hot water in the hot water storage tank 10 in FIG. Can shift to pipe freezing prevention operation.

  When the temperature detected by the HP outlet side temperature sensor 66 rises to a predetermined temperature or higher (for example, 10 ° C. or higher) after the transition to the heat pump pipe freezing prevention operation using the high-temperature water in the hot water storage tank 10 of FIG. 70 may determine that the risk of freezing has been eliminated. In that case, the control device 70 stops the operation of the circulation pump 21 or switches the first four-way valve 31 from the fourth flow path form to the first flow path form to perform the heat pump pipe freezing prevention operation of FIG. May continue further.

  The remote controller 80 has a function of accepting a user operation related to a change in driving operation command and set value. The remote controller 80 is an example of an operation terminal or a user interface device. The control device 70 and the remote controller 80 are connected so as to be capable of bidirectional data communication by wire or wireless. The remote controller 80 is equipped with a display unit that displays information such as the state of the hot water storage hot water supply system 1, an operation unit such as a switch operated by a user, a speaker, a microphone, and the like. The remote control 80 may be installed in the kitchen. The remote control 80 may be installed in a bathroom. The hot water storage type hot water supply system 1 may include a plurality of remote controllers 80.

  The hot water storage type hot water supply system 1 has means for notifying the user of information regarding the above-described plural types of operation states, which differ depending on the flow path configuration of the first four-way valve 31 and the flow path configuration of the second four-way valve 32. You may prepare. For example, information on which of the above-described plural types of driving is being performed may be displayed on the display unit of the remote controller 80 or may be guided by voice from the remote controller 80. By doing so, the user can easily check the operating state of the hot water storage type hot water supply system 1 and the user convenience is improved.

  In the second four-way valve 32 in the present embodiment, the heat pump outlet pipe 42 communicates with the upper part of the hot water storage tank 10 via the tank upper pipe 43, and the heat pump outlet pipe 42 passes through the tank return pipe 44. This is an example of the flow path switching means capable of switching the flow path form communicating with the return port 14 located at a position lower than the upper portion of the hot water storage tank 10. Further, the second four-way valve 32 in the present embodiment has a flow path configuration in which hot water downstream of the circulation pump 21 returns to the hot water storage tank 10 via the bypass pipe 47 without passing through the heat pump unit 60. It is an example of the flow path switching means which can be switched. By providing these flow path switching means, more various forms of operation can be performed. These flow path switching means are not limited to the second four-way valve 32, and can be replaced with other valve configurations that can exhibit the same function.

  In the first embodiment described above, the heat pump cycle is a supercritical heat pump cycle in which the refrigerant pressure is equal to or higher than the critical pressure, but it goes without saying that the heat pump cycle may be equal to or lower than the critical pressure. In this case, chlorofluorocarbon gas, ammonia, or the like may be used as the refrigerant.

  Each of the control device 70 of the hot water storage type hot water supply system 1 and the control device included in the remote controller 80 may be configured as follows. Each function of the control device may be realized by a processing circuit. The processing circuit of the control device may comprise at least one processor and at least one memory. When the processing circuit includes at least one processor and at least one memory, each function of the control device may be realized by software, firmware, or a combination of software and firmware. At least one of software and firmware may be described as a program. At least one of the software and firmware may be stored in at least one memory. The at least one processor may realize each function of the control device by reading and executing a program stored in at least one memory. The at least one memory may include a nonvolatile or volatile semiconductor memory, a magnetic disk, or the like.

  The processing circuit of the control device may include at least one dedicated hardware. When the processing circuit includes at least one dedicated hardware, the processing circuit may be, for example, a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an ASIC (Application Specific Integrated Circuit), or an FPGA (Field-). (Programmable Gate Array) or a combination thereof. The function of each part of the control device may be realized by a processing circuit. Further, the functions of the respective units of the control device may be collectively realized by a processing circuit. Some of the functions of the control device may be realized by dedicated hardware, and the other part may be realized by software or firmware. The processing circuit may realize each function of the control device by hardware, software, firmware, or a combination thereof.

  The configuration is not limited to the configuration in which the operation is controlled by a single control device, and the configuration may be such that the operation is controlled by cooperation of a plurality of control devices.

DESCRIPTION OF SYMBOLS 1 Hot water storage type hot water supply system, 2 Hot water supply piping, 3 Hot water supply piping, 10 Hot water storage tank, 11, 12, 13 Hot water storage temperature sensor, 14 Return port, 20 Hot water storage tank unit, 21 Circulation pump, 22 Use side heat exchanger, 31 1st No. 4 way valve, 32 2nd 4 way valve, 33, 34 branch, 40 Low temperature pipe, 41 Heat pump inlet pipe, 42 Heat pump outlet pipe, 43 Tank upper pipe, 44 Tank return pipe, 45 Bypass path, 47 Bypass pipe, 48 High temperature piping, 50 bathtubs, 51 bathtub water circulation circuit, 52 bathtub water circulation pump, 53 bathtub water temperature sensor, 60 heat pump unit, 61 compressor, 62 water-refrigerant heat exchanger, 63 expansion valve, 64 air heat exchanger, 65 refrigerant Circulation piping, 66 HP outlet side temperature sensor, 70 control device, 80 remote control

Claims (8)

A heat storage tank for storing a heat medium;
Heating means for heating the heat medium;
A four-way valve,
A use side heat exchanger for exchanging heat between the heat medium and the use side medium;
A circulation pump;
Low temperature piping connecting the lower part of the heat storage tank and the four-way valve;
A high-temperature pipe connecting the upper part of the heat storage tank and the four-way valve;
An inlet-side path leading from the four-way valve to the inlet of the heating means via the circulation pump;
An outlet side path leading to an outlet of the heating means;
A bypass path connected to the upstream side of the circulation pump of the inlet side path from the four-way valve via the use side heat exchanger;
Control means for controlling the four-way valve;
With
A first flow path configuration in which the low-temperature pipe communicates with the inlet-side path via the four-way valve;
A second flow path configuration in which the high-temperature pipe communicates with the bypass path via the four-way valve;
A third flow path configuration in which the low-temperature pipe communicates with the bypass path via the four-way valve;
The heat storage system that is selectable. During the operation of heating the utilization side medium, the four-way valve is controlled to be in the second flow path form,
2. The heat storage system according to claim 1, wherein the four-way valve is controlled so that the third flow path is configured in an operation of recovering waste heat of the use-side medium in the heat storage tank. Means for detecting the temperature of the user-side medium;
3. The control according to claim 1, wherein, in the freeze prevention operation, whether the four-way valve is in the first flow path configuration or the third flow path configuration is controlled according to the temperature of the use side medium. Heat storage system.   The heat medium preheated by waste heat of the use-side medium by forming the four-way valve in the third flow path form during the heat storage operation in which the heat medium heated by the heating means is stored in the heat storage tank. The heat storage system according to any one of claims 1 to 3, wherein the heat can be supplied to the heating means. A fourth flow path configuration in which the high-temperature pipe communicates with the inlet-side path via the four-way valve can be selected;
The four-way valve is configured as the fourth flow path, and the heating medium flowing out from the heat storage tank to the high-temperature pipe in the state where the heating unit is stopped is transferred to the inlet side path, the heating unit, and the outlet side path. The heat storage system as described in any one of Claims 1-4 which can perform the operation | movement returned to the said thermal storage tank via a.   The heat storage system according to any one of claims 1 to 5, further comprising means for notifying information on a plurality of types of operation states according to a flow path configuration of the four-way valve.   A flow path switching means capable of switching between a flow path form in which the outlet side path communicates with an upper part of the heat storage tank and a flow path form in which the outlet side path communicates with a position lower than the upper part of the heat storage tank. The heat storage system as described in any one of Claims 1-6.   The flow medium switching means according to any one of claims 1 to 7, further comprising a flow path switching means capable of switching to a flow path form in which the heat medium downstream of the circulation pump returns to the heat storage tank without passing through the heating means. Heat storage system.

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