JP2013002677A - Hot water storage system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hot water storage system preventing hot water in a hot water storage tank from being cooled by circulation of a heating medium, naturally caused in night time.SOLUTION: During the heat collecting operation, a switching valve 25 is set to an open state and a circulation pump 24 is operated to make the heating medium circulate in a heating medium circulation path 22 so as to pass through a heat collection device 21, heat obtained by the circulating heating medium in the heat collection device 21 is radiated in a heat exchanger 18 to perform control to heat water in the hot water storage tank 14. After finishing the heat collecting operation, in order to prevent the heat radiation phenomenon of the heat in the hot water storage tank side in the heat collection device due to natural circulation of the heating medium in the heating medium circulation path, even when the circulation pump 24 is stopped, the switching valve 25 is switched to a closed state to prevent flow of the heating medium into the heat collection device 21 side (broken line part in a figure).

Description

  The present invention heats water in a hot water storage tank provided for hot water by circulating a heat medium in a circulation path that passes through a solar heat collector and a heat exchanger for heating the water in the hot water storage tank. It relates to a hot water storage system.

  In a hot water storage system that heats a heat medium with a heat collector that uses solar heat and releases the heat of the heat medium with a heat exchanger to raise the temperature of the water in the hot water storage tank, usually the heat medium in the heat collector When the temperature is higher than the water temperature around the heat exchanger by a predetermined temperature or more, the heat medium circulation pump is driven to start the heat collecting operation, and when the temperature difference becomes a certain value or less, the heat collecting operation is stopped. Done.

  In addition, since the heat collection effect is poor at night and the drive sound of the circulation pump is likely to be a problem, the sunshine sensor is used to distinguish between daytime and nighttime, and the above temperature difference satisfies the conditions for starting heat collection operation. Even so, there is a system that prohibits heat collection operation at night (see, for example, Patent Document 1).

JP-A-1-302070

  At night, the heat medium in the heat collector is cooled as the outside air temperature decreases. On the other hand, since the hot water storage tank is wrapped with a heat insulating material, the water in the hot water storage tank is maintained at a high temperature unless hot water heated in the daytime heat collecting operation is used.

  By the way, in order to control to stop or prohibit the heat collecting operation at night, the circulation pump is stopped, but nevertheless, the heat medium may start to circulate for some reason. Once circulation begins, as described above, the heat collector is cold and the hot water in the hot water tank is hot, so the hot water in the hot water tank rises by the draft force (specific gravity difference) and reaches the heat collector. On the other hand, there is a problem that the heat medium cooled by the heat collecting device flows toward the hot water storage tank below and stops circulating, and the hot water in the hot water storage tank is completely cooled the next morning.

  An object of the present invention is to provide a hot water storage system capable of preventing the hot water in a hot water storage tank from being cooled by circulation of a heat medium naturally generated at night.

  The gist of the present invention for achieving the object lies in the inventions of the following items.

[1] A solar heat collector,
A hot water storage tank that stores hot water supplied to the hot spring and is replenished with water from the water supply channel;
A heat exchanger for heating the water in the hot water storage tank;
A heat medium circulation path for circulating a heat medium via the heat exchanger and the heat collector;
A circulation pump for circulating the heat medium in the heat medium circulation path;
A switching valve that is provided in the heat medium circulation path and switches between a state where the path between the heat collector and the heat exchanger is blocked and a state where the path is opened;
By setting the switching valve to the opened state and operating the circulation pump, the heat medium is circulated in the heat medium circulation path, and the circulating heat medium generates the heat obtained by the heat collector. A controller for controlling a heat collecting operation for heating the water in the hot water storage tank by discharging it with a heat exchanger;
Have
The control unit is the heat collecting device in which the heat medium naturally circulates in the heat medium circulation path and the heat on the hot water storage tank side is cooled even if the circulation pump is stopped after the heat collecting operation is finished. A hot water storage system, wherein the switching valve is in the shut-off state in order to prevent a released heat radiation phenomenon.

  In the above invention, even if the circulation pump is stopped after the end of the heat collection operation, the heat medium naturally circulates in the heat medium circulation path and the heat dissipation phenomenon in which the heat on the hot water storage tank side is released by the heat collection device is prevented. Therefore, the switching valve is switched to the shut-off state. The switching may be performed by detecting an arbitrary matter capable of detecting the situation where the heat dissipation phenomenon occurs. For example, the night may be detected and switched based on the sunshine situation and time, or the temperature may be switched depending on the temperature condition such that the temperature on the heat collecting device side is lower than the water temperature on the hot water storage tank side. When the occurrence is actually detected by a flow sensor or the like, it may be switched to a cut-off state or any other method. As long as the period in which the heat dissipation phenomenon occurs can be covered, the other period may be included in the blocking period. The heat collecting operation is performed at least when the temperature of the heat medium in the heat collecting device is higher than the water temperature around the heat exchanger of the hot water storage tank.

[2] In the above [1], the control unit prevents the heat dissipation phenomenon by setting the switching valve to the shut-off state at night after the heat collecting operation for one day is completed. The hot water storage system described.

  In the above-described invention, switching to the shut-off state can be performed once a day, so that deterioration of the switching valve due to frequent switching is prevented.

[3] A flow sensor is provided in the heat medium circulation path,
The control unit prevents the heat dissipation phenomenon by switching the switching valve to the shut-off state when the flow sensor detects circulation of the heat medium while the circulation pump is stopped. The hot water storage system according to 1].

  In the above invention, the switching valve is switched to the shut-off state when it is detected that natural circulation has actually occurred. Thereby, since switching is performed only when necessary, deterioration of the switching valve due to frequent switching is prevented.

[4] A first temperature sensor for detecting the temperature of the heat medium in the heat collecting device;
A second temperature sensor for detecting a water temperature around the heat exchanger;
With
The controller prevents the heat dissipation phenomenon by causing the switching valve to be shut off when the temperature detected by the first temperature sensor is lower than the temperature detected by the second temperature sensor. The hot water storage system according to [1].

  In the said invention, generation | occurrence | production of the circulation by draft force is estimated from a temperature difference, and when the temperature conditions which can generate | occur | produce natural circulation are satisfied, a switching valve is switched to a cutoff state.

[5] The hot water storage system according to [1], wherein the control unit switches the switching valve to the shut-off state when the heat collecting operation is not performed.

  In the above invention, when the heat collecting operation is not performed, the switching valve is switched to the shut-off state. The switching timing can be easily determined and the control is simplified.

[6] The control unit prohibits the heat collection operation when the time indicated by the clock unit is not within a predetermined heat collection operation permission time zone. Any one of [1] to [5] Hot water storage system as described in one.

  In the said invention, it is judged based on the time which a timepiece measures whether it is in the state which should prohibit heat collection driving | operation. For example, if the permitted time zone is from 4 o'clock to 19 o'clock and the time of the clock is outside the time zone, the heat collecting operation is prohibited. Note that the switching valve may be switched to a shut-off state during a time period in which the heat collection operation is prohibited.

[7] The control unit may be configured such that the temperature of the heat medium in the heat collecting device is equal to or higher than a predetermined temperature even when the clock unit is not set or the time indicated by the clock unit is not within the permitted time zone. The hot water storage system according to [6], wherein the heat collecting operation is started.

  In the above invention, when the time is not set in the timepiece unit or the time may be out of order, such a case is assumed, and temperature conditions suitable for heat collection (for example, outside the permitted time zone (for example, If a temperature condition that can reliably determine that there is solar radiation from the temperature of the high temperature sensor is established, the heat collection operation is started.

[8] The heat medium circulation path includes a cross-linked polyethylene pipe portion;
The control unit prohibits the heat collection operation while the temperature of the heat medium in the heat collection device is equal to or higher than the heat resistant temperature of the crosslinked polyethylene pipe. Any one of [1] to [7] Hot water storage system as described in one.

  In the above invention, when the heat medium in the heat collecting device exceeds the heat resistance temperature of the crosslinked polyethylene pipe, the heat collecting operation is prohibited (the circulation pump is stopped) so that the high-temperature heat medium does not reach the part of the crosslinked polyethylene pipe. )

[9] The switching valve forms the shut-off state by switching the heat medium circulation path to a circulation path that bypasses the heat collecting device. Any one of [1] to [8] Hot water storage system as described in one.

  In the said invention, interruption | blocking is performed by switching a heat-medium circulation path so that a heat collecting device may be bypassed.

  According to the hot water storage system according to the present invention, the hot water in the hot water storage tank heated by the heat collecting operation during the day is prevented from being cooled by the circulation of the heat medium naturally generated at night.

It is explanatory drawing which shows the structure of the hot water supply system containing the hot water storage system of this invention. It is explanatory drawing which shows schematic structure of the water heater as an auxiliary heat source machine. It is explanatory drawing which shows schematic operation | movement of heat collecting operation. It is explanatory drawing which shows the interruption | blocking state after completion | finish of heat collection driving | operation. It is explanatory drawing which shows schematic operation | movement of a hot water supply driving | operation. It is explanatory drawing which shows schematic operation | movement of a solar reheating operation. It is explanatory drawing which shows schematic operation | movement of a bath heat recovery driving | operation. It is explanatory drawing which shows the driving | running state in hot water storage hot water prohibition. It is a flowchart which shows the operation | movement of the whole heat collection driving | operation including a start determination. It is a flowchart which shows the operation | movement in heat collection driving | operation.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 shows a configuration of a hot water supply system 10 including a hot water storage system of the present invention. The hot water supply system 10 includes a hot water storage system 11 and a hot water heater 12 as an auxiliary heat source machine.

  The hot water storage system 11 includes a hot water storage tank 14 that stores hot water heated using sunlight, and supplies hot water from the hot water storage tank 14 to the water inlet of the water heater 12. The hot water heater 12 serving as an auxiliary heat source device fulfills the function of heating the water supplied from the hot water storage system 11 to a set temperature as needed and discharging the hot water to the hot water supply pipe 13. The hot water storage system 11 preferentially uses hot water heated by sunlight to suppress heating by the hot water heater 12 (hereinafter referred to as “follow-up heating”), and to save hot water with energy saving. Enable.

  A detailed configuration of the hot water storage system 11 will be described. The hot water storage tank 14 is a hollow, substantially cylindrical tank, and has piping connection ports at the bottom and the ceiling. The terminal end of the water supply pipe 15 is connected to the bottom pipe connection port. One end of the connection pipe 16 is connected to the pipe connection port of the ceiling, and the other end of the connection pipe 16 is connected to the water inlet of the water heater 12.

  A mixing valve 17 that mixes hot water and hot water from the hot water storage tank 14 is provided in the middle of the connection pipe 16. Here, the mixing valve 17 includes two valves, a first valve 17a and a second valve 17b. The first valve 17 a is inserted in the connection pipe 16. The second valve 17b is inserted in the middle of the branch water supply pipe 15a which branches from the middle of the water supply pipe 15 and merges with the connection pipe 16 on the water heater 12 side of the first valve 17a. The first valve 17a and the second valve 17b are water amount adjusting valves whose opening degrees (water flow amount) can be adjusted from 0% to 100%, respectively. The mixing ratio of hot water and hot water from the hot water storage tank 14 is adjusted by the opening degree of the first valve 17a and the second valve 17b.

  The hot water storage tank 14 has, for example, a capacity of 100 liters, and a first temperature sensor 41 for detecting the water temperature at a water level of 20 liters from the bottom is located at a water level of 40 liters from the bottom. The second temperature sensor 42 for detecting the water temperature of the water is located at a location where the water level is 60 liters from the bottom, and the third temperature sensor 43 for detecting the water temperature at that location is located at the location where the water level is 80 liters from the bottom. A fourth temperature sensor 44 for detecting the above is provided.

  In addition, the connection piping 16 in the vicinity of the piping connection port on the ceiling of the hot water storage tank 14 is provided with a tank hot water temperature sensor 46 that detects the temperature of the hot water coming out of the hot water storage tank 14. A water supply temperature sensor 47 for detecting the water supply temperature is provided in the middle of the water supply pipe 15. Further, a water amount sensor 48 is detected in the connection pipe 16 on the outlet side (hot water heater 12 side) of the mixing valve 17, and the temperature of hot water after mixing is detected by the mixing valve 17 on the downstream side (hot water heater 12 side). A mixed temperature sensor 49 is provided.

  A heat exchange pipe 18 that forms part of the heat medium circulation path 22 is inserted through the lower part of the hot water storage tank 14. The heat medium circulation path 22 circulates the heat medium (here, water) via the heat exchange pipe 18, the cistern 19, the water-water heat exchanger 20, and the solar heat collecting device 21. It is a route.

  Specifically, the heat medium circulation path 22 includes the first heat medium pipe 22 a extending from the outlet side of the heat exchange pipe 18 to the inlet side of the cistern 19 and the inlet of the water-water heat exchanger 20 from the outlet side of the cistern 19. The second heat medium pipe 22b extending to the side, the third heat medium pipe 22c extending from the outlet side of the water-water heat exchanger 20 to the inlet side of the heat collector 21, and for heat exchange from the outlet side of the heat collector 21. It consists of a fourth heat medium pipe 22d that reaches the entry side of the pipe 18. In the figure, the heat collecting device 21 is a component of the hot water storage system 11, but may be an external device.

  The cistern 19 is a tank for storing a heat medium circulating in the heat medium circulation path 22. The cistern 19 is a tank that is open to atmospheric pressure, and absorbs volume fluctuations due to expansion and contraction of the heat medium. The cistern 19 includes a water level sensor 19a that detects the internal water level. The water level sensor 19a of this example includes a low water level detection electrode, a high water level detection electrode, and a common electrode.

  The water-water heat exchanger 20 has two pipes in close contact with each other over a predetermined length, and plays a role of transferring heat from a high temperature side pipe to a low temperature side pipe. The heat medium circulation path 22 is connected to the entry side and the exit side of one pipe line (in the figure, the inner pipe line 20a) of the water-water heat exchanger 20.

  A circulation pump 24 is provided in the middle of the third heat medium pipe 22c from the outlet side of the water-water heat exchanger 20 (inner pipe line 20a) to the inlet side of the heat collector 21. The circulation pump 24 sends the heat medium in the third heat medium pipe 22c to the heat collector 21 side. A switching valve 25 is inserted in the third heat medium pipe 22 c on the downstream side of the circulation pump 24. A third heat medium pipe 22c from the circulation pump 24 side is connected to the first connection port 25a of the switching valve 25, and a third heat medium reaching the heat collector 21 side is connected to the second connection port 25b of the switching valve 25. A pipe 22c is connected. One end of a connection pipe 26 is connected to the third connection port 25c of the switching valve 25, and the other end of the connection pipe 26 is a fourth heat medium pipe extending from the heat collecting device 21 to the entrance side of the heat exchange pipe 18. 22d is joined and connected in the middle.

  The main body of the hot water storage system 11 such as the hot water storage tank 14 is installed on the ground, and the heat collecting device 21 is installed on the roof above the main body of the hot water storage system 11. Of the third heat medium pipe 22c, a part of the connecting piping from the connecting part 27a with the main body side of the hot water storage system 11 to the heat collecting device 21 and a part returning from the heat collecting apparatus 21 to the connecting part 27b with the main body side of the hot water storage system 11 Cross-linked polyethylene pipe is used for the connecting pipe. The heat resistance temperature of the cross-linked polyethylene pipe is 90 ° C. to 95 ° C. depending on the water pressure and the set service life.

  The heat collector 21 is provided with a high temperature sensor 51 that detects the temperature of hot water in the heat collector 21. Further, a heat medium temperature sensor 52 for detecting the temperature of the heat medium passing through the fourth heat medium pipe 22d on the heat exchanging pipe 18 side is provided in the middle of the joint connection place of the connecting pipe 26.

  The water heater 12 heats the hot water supplied from the water inlet to a set temperature and discharges it to the hot water supply pipe 13, and also heats the water supplied from the water inlet to the set temperature of the bath and pours it into the bathtub 3. It has a tensioning function and a chasing function for chasing hot water in the bathtub 3.

  The recirculation path for circulating hot water during reheating is a bath return pipe 32 for taking hot water from the bathtub 3 into the water heater 12, a pipe passing through the heat exchanger in the water heater 12, and the heat exchanger. It comprises a bath outlet pipe 31 for sending warm hot water to the bathtub 3 and the like. The bath outlet pipe 31 reaches the bathtub 3 via the other pipe line (outer pipe line 20b in the figure) of the water-water heat exchanger 20 on the way.

  Between the water heater 12 and the water-water heat exchanger 20, a bath temperature sensor 53 for detecting the temperature of hot water taken from the bathtub 3 is provided.

  In addition, the connecting pipe 16 between the tank hot water temperature sensor 46 and the mixing valve 17 (first valve 17a) is provided with a hot water prohibiting electromagnetic valve 54 for switching between closing and opening of the connecting pipe 16. Further, two branch pipes branched from the connection pipe 16 are provided between the hot water prohibition solenoid valve 54 and the tank hot water temperature sensor 46, and a drain electromagnetic valve 55 is provided at one end of the branch pipe and the other branch pipe is provided. Is provided with a pressure relief valve 56. Further, a water filter, a pressure reducing valve, a check valve and the like are inserted in the water supply pipe 15.

  The hot water storage system 11 includes a control unit 60 that performs overall control of the operation of the hot water storage system 11. The control unit 60 temporarily stores a CPU (Central Processing Unit), a flash ROM (Read Only Memory) in which programs executed by the CPU, fixed data, and the like are stored, and various information when the CPU executes the programs. A RAM (Random Access Memory), an I / F unit for inputting / outputting various signals, and the like are configured as circuits. Detection signals from various sensors of the hot water storage system 11 are input to the control unit 60. In addition, a control signal is output from the control unit 60 to the control target such as each valve and the circulation pump 24.

  The control unit 60 of the hot water storage system 11 exchanges necessary information with the control base 70 of the water heater 12. Here, the control unit 60 provides information on the set temperature set on the water heater 12 side, information indicating whether or not the water heater 12 is in a chasing operation, time information on the clock unit of the water heater 12, and the like. Obtained from the vessel 12. Further, a signal for instructing combustion prohibition / permission and a signal for driving the bath circulation pump 85 (see FIG. 2) without burning the burner 73 (bath pump drive signal) are sent from the control unit 60 to the control board 70 of the water heater 12. Send.

  FIG. 2 shows a schematic configuration of the water heater 12. The water heater 12 includes a hot water supply water pipe 72a in which a water inlet pipe 71 is connected to the inlet side and a hot water supply pipe 13 to the outlet side, and a bath return pipe 31 on the outlet side and a bath return pipe 32 to the inlet side. A one-can two-water channel type heat exchanger 72 provided with a water pipe 72b for watering is provided. The starting end of the water intake pipe 71 is a water inlet to which the connection pipe 16 from the hot water storage system 11 side is connected.

  The heat exchanger 72 includes a large number of fins 72c for receiving heat from the burner 73 disposed below. A gas supply pipe 74 is connected to the burner 73. In the middle of the gas supply pipe 74, a gas valve 75 for switching supply / cutoff of gas, a proportional valve 76 for adjusting the amount of supply gas, and the like are provided.

  The hot water supply pipe 13 and the bath return pipe 32 are connected by a connecting pipe 77, and a pouring electromagnetic valve 78 that switches between closing and opening of the connecting pipe 77 is provided in the middle of the connecting pipe 77. Further, in the middle of the hot water supply pipe 13 upstream from the connection point of the connecting pipe 77, a water amount servo 79 capable of adjusting the opening degree from the closed state to the fully opened state is provided in order to adjust the amount of discharged hot water. A tapping temperature sensor 80 for detecting tapping temperature is provided on the downstream side of the water amount servo 79.

  Furthermore, a bypass pipe 81 branched from the water inlet pipe 71 and joined to and connected to the hot water supply pipe 13 at a predetermined location on the hot water supply water pipe 72a side from the water quantity servo 79 is provided. A bypass adjustment valve 82 capable of adjusting the degree is provided. The inlet pipe 71 upstream of the branching point of the bypass pipe 81 is provided with a flow rate sensor 83 that detects the flow rate of water in the inlet pipe 71 and an incoming temperature sensor 84 that detects the incoming water temperature. In addition, in the instrument which estimated the incoming water temperature by calculation, the incoming water temperature sensor 84 may not be provided.

  In the middle of the bath return pipe 32, there is provided a bath circulation pump 85 for circulating the water in the bathtub 3 through the reheating circulation path (the bath return pipe 32, the reheating water pipe 72b, the bath going-out pipe 31). . A flowing water switch 86 provided in the bath return pipe 32 detects whether water is actually circulating in the recirculation path when the bath circulation pump 85 is operated.

  In addition, a bath-out temperature sensor 87 and a bath-return temperature sensor 88 are provided in the bath-out tube 31 and the bath-return tube 32, respectively.

  The control board 70 includes a CPU, a flash ROM that stores programs executed by the CPU, fixed data, and the like, and a RAM that temporarily stores various types of information when the CPU executes programs. Has been. Various sensors, valves, bath circulation pumps 85 and the like that the water heater 12 has are connected to the control base 70.

  Further, an operation panel (remote control) 89 is connected to the control board 70 via wiring. The operation panel 89 includes a switch for receiving various operations from the user, such as designation of a set temperature for hot water supply and a set temperature for a bath, start / end instructions for hot water filling and reheating, and power on / off, It consists of a display unit that displays the set temperature. The operation panel 89 also includes a clock unit 89a that measures time. The time counted by the clock unit 89a is displayed on the display unit of the operation panel 89. Further, the time information counted by the clock unit 89a is notified to the control unit 60 of the hot water storage system 11.

  In the hot water supply operation for discharging hot water from the hot water supply pipe 13, the control base 70 of the water heater 12 opens the combustion amount of the burner 73 and opens the bypass adjustment valve 82 so that hot water at the hot water supply set temperature set by the user on the operation panel 89 is discharged. Control the degree.

  In the hot water filling operation for pouring water into the bathtub 3, the control base 70 is heated through the hot water supply water pipe 72 a of the heat exchanger 72 by opening the hot water solenoid valve 78 and the water amount servo 79 with the burner 73 burned. Hot water is sent from the hot water supply pipe 13 to the connecting pipe 77 and flows into the bathtub 3 through both the bath return pipe 32 and the bath outlet pipe 31. At this time, the control board 70 controls the combustion amount of the burner 73, the opening degree of the bypass adjustment valve 82, and the like so that hot water having a bath set temperature set by the user on the operation panel 89 is poured. Further, when the water level in the bathtub 3 reaches the set water level, the pouring operation is stopped and the reheating operation is performed.

  In the reheating operation, the pouring electromagnetic valve 78 is closed, and the burner 73 is burned with the bath circulation pump 85 activated. As a result, the hot water in the bathtub 3 is taken into the water heater 12 through the bath return pipe 32 and heated, and the hot water after overheating is sent out to the bathtub 3 through the bath outlet pipe 31.

  The burner 73 of the water heater 12 cannot be combusted below a predetermined minimum heating amount (minimum number). Therefore, the control board 70 of the water heater 12 controls the burner 73 to be in a state where the burner 73 is burned off when the heating amount necessary for taking out the hot water at the set temperature is smaller than the minimum heating amount. The necessary amount of heating is calculated based on the temperature difference between the set temperature and the incoming water temperature detected by the incoming water temperature sensor 84, the flow rate detected by the flow sensor 83, the thermal efficiency, and the like.

  Next, various operations of the hot water storage system 11 will be described.

<Heat collection operation>
FIG. 3 shows a schematic operation of the heat collecting operation performed by the hot water storage system 11. The heat collecting operation is an operation of heating the water in the hot water storage tank 14 using heat obtained from sunlight by the heat collecting device 21. The heat collection operation is performed when an operation condition is satisfied such that the temperature detected by the high temperature sensor 51 of the heat collection device 21 is higher than the water temperature in the hot water storage tank 14 by a certain temperature or more.

  The hot water storage tank 14 receives supply of water from a water supply pipe 15 connected to a pipe connection port at the bottom, and is normally in a full state. During the heat collection operation, the control unit 60 sets the switching valve 25 in a state where the first connection port 25a and the second connection port 25b communicate with each other and closes the third connection port 25c (heat collection side), and then circulates. The pump 24 is driven.

  In FIG. 3, the path through which the heat medium (water) circulates in the heat collecting operation is indicated by a bold line. The direction in which the heat medium flows in each part is indicated by arrows. Specifically, the heat medium in the cistern 19 flows toward the heat collecting device 21 through the third heat medium pipe 22c or the like by the action of the circulation pump 24, and is heated and heated when passing through the heat collecting device 21. Then, the refrigerant circulates from the fourth heat medium pipe 22d through the heat exchanging pipe 18 in the hot water storage tank 14 to return to the system 19. When the water temperature in the hot water storage tank 14 is lower than the heat medium passing through the heat exchange pipe 18, the heat of the heat medium moves to the water in the hot water storage tank 14 through the heat exchange pipe 18 and the water in the hot water storage tank 14 is heated. Is done.

  The heat exchange pipe 18 is located below the hot water storage tank 14, and water is supplied from the bottom of the hot water storage tank 14, and hot water flows out from the ceiling of the hot water storage tank 14 to the connection pipe 16. Has a lower temperature and a higher temperature gradient at the ceiling.

  The control unit 60 of the hot water storage system 11 sets the switching valve 25 in a shut-off state in which the first connection port 25a and the third connection port 25c communicate with each other and the second connection port 25b is closed when the heat collecting operation of the day ends. To do. FIG. 4 shows a blocking state. In the shut-off state, the heat medium circulation path 22 is switched to a circulation path that circulates the heat medium bypassing the heat collecting device 21, and is collected from the second connection port 25b of the switching valve 25 in the third heat medium pipe 22c. The part leading to the heat device 21 is separated from the circulation path. Thereby, in the shut-off state, heat is generated in a pipe portion (a portion indicated by a broken line in the drawing) from the second connection port 25b of the switching valve 25 to the joining connection location with the connecting pipe 26 via the heat collecting device 21. There is no medium flow.

  By setting the shut-off state, the heat dissipation phenomenon that the hot water in the hot water storage tank 14 warmed by the heat collecting operation during the day is cooled by the heat collecting device 21 due to the circulation of the heat medium naturally generated at night is prevented.

  That is, at night, the heat medium in the heat collector 21 is cooled as the outside air temperature decreases, but since the hot water storage tank is wrapped with a heat insulating material, the hot water heated by the heat collecting operation during the day is used. Is not used much, the water in the hot water tank is maintained at a high temperature. At night, the heat collecting operation is stopped or prohibited to stop the circulation pump 24. Nevertheless, the heat medium may start to circulate naturally for some reason. Once the circulation starts, the warm water in the hot water storage tank 14 rises by the draft force (specific gravity difference) and reaches the heat collecting device 21, and the heat medium cooled by the heat radiation from the cold heat collecting device 21 is downward. Since the heat flows toward the hot water storage tank 14, a heat dissipation phenomenon occurs in which the circulation does not stop. As a result, the next morning, the hot water in the hot water storage tank 14 is completely cooled.

  In the hot water storage system 11 of the present invention, after the heat collecting operation of the day is finished, the switching valve 25 is switched to a shut-off state to prevent the heat dissipation phenomenon from occurring. Detailed control of the heat collection operation will be described later.

<Hot water supply operation>
FIG. 5 shows a schematic operation of the hot water supply operation. In FIG. 5, the path through which hot water flows in the hot water supply operation is indicated by a thick line. The direction in which hot water flows in each part is indicated by arrows. In the hot water supply operation, hot water from the hot water storage tank 14 and water supplied from the branch water supply pipe 15a are mixed by the mixing valve 17 and supplied to the water inlet (water inlet pipe 71) of the water heater 12. The hot water heater 12 heats the supplied water as necessary so that the hot water is discharged at a set temperature, and discharges the hot water to the hot water supply pipe 13.

<Solar chasing operation>
FIG. 6 shows a schematic operation of the solar reheating operation. The solar reheating operation is an operation in which hot water in the bathtub 3 is supplementarily replenished using heat obtained from sunlight by the heat collecting device 21.

  In the solar reheating operation, the control unit 60 sets the switching valve 25 in a state where the first connection port 25a communicates with the second connection port 25b and closes the third connection port 25c, and then drives the circulation pump 24. To do. That is, the heat medium is circulated in the same manner as in the heat collection operation, and the heat medium is heated by the heat collection device 21. Further, in the solar reheating operation, the control unit 60 instructs the water heater 12 to drive the bath circulation pump 85 in a state where combustion (heating operation) is stopped.

  In FIG. 6, the path through which the heat medium (water) circulates in the solar reheating operation is indicated by a thick line. Moreover, the circulation path of bathtub water is shown with the thick broken line. Furthermore, the direction in which the heat medium flows and the direction in which the bath water flows are indicated by arrows in each part. In the solar reheating operation, the operation condition is that the temperature of the heat medium circulating in the heat medium circulation path 22 is higher than the temperature of the bath water, and the water-water heat exchanger 20 passes through the inner pipe line 20a. The bathtub water is heated by heat moving from the heat medium to the bathtub water passing through the outer pipe line 20b.

<Bath heat recovery operation>
FIG. 7 shows a schematic operation of the bath heat recovery operation. The bath heat recovery operation is an operation of heating the hot water in the hot water storage tank 14 using the heat of the remaining hot water in the bath.

  In the bath heat recovery operation, the control unit 60 sets the switching valve 25 in the above-described shut-off state in which the first connection port 25a and the third connection port 25c communicate with each other and closes the second connection port 25b, and then the circulation pump 24 is driven. As a result, the heat medium circulates through the water-water heat exchanger 20 and the hot water storage tank 14 without passing through the heat collector 21. Further, the hot water heater 12 is instructed to drive the bath circulation pump 85 in a state where combustion (heating operation) is stopped. As a result, the bathtub water circulates in the recirculation circulation path including the outer conduit 20 b of the water-water heat exchanger 20.

  In FIG. 7, the path through which the heat medium (water) circulates in the bath heat recovery operation and the circulation path of the bath water are indicated by bold lines. Moreover, the circulation path of bathtub water is shown with the thick broken line. Furthermore, in each part, the direction in which the heat medium flows and the direction in which the bathtub water flows are indicated by arrows. The bath heat recovery operation has an operation condition such that the water temperature in the hot water storage tank 14 (first temperature sensor 41) is lower than the water temperature in the bathtub 3, and the water-water heat exchanger 20 passes through the outer conduit 20b. Heat moves from the bathtub water to the bathtub water passing through the inner pipe line 20a, and this heat moves to the water in the hot water storage tank 14 through the heat exchange pipe 18, whereby the water in the hot water storage tank 14 is heated. Thereby, the burden of heat collection operation is reduced.

  The bath heat recovery operation is performed, for example, when the operation (power) switch of the bath remote control of the bath is turned off, or when a set time (for example, 10 o'clock at night) comes, or a dedicated bath heat recovery operation button This is done when is pressed. At the start of the bath heat recovery operation, first, the bath circulation pump 85 is temporarily activated to check whether there is bathtub water. Then, when there is bathtub water and the temperature of the bathtub water is higher than the temperature detected by the first temperature sensor 41 by a predetermined temperature (for example, 15 ° C.) or more, the bath heat recovery operation is performed, and the difference is 10 ° C. or less or 1 hour. If it exceeds, driving is stopped. The time limit is based on the durability of the bath circulation pump 85.

<No hot water storage or hot water operation>
If the hot water in the hot water storage tank 14 is stopped for 100 hours or more, there is a problem due to reproduction of Legionella bacteria, and sterilization is performed as a countermeasure. In the hot water storage hot water prohibition operation, hot water discharge from the hot water storage tank 14 is prohibited, and sterilization is performed by continuing the state in which the water in the hot water storage tank 14 is 60 degrees or more for 15 minutes or longer.

  FIG. 8 shows an operating state when hot water storage and hot water discharge is prohibited. If most of the hot water in the hot water storage tank 14 is not used within 98 hours (here, 93 liters in 100 liters), the hot water storage hot water discharge prohibition operation is started. In the hot water storage hot water prohibition operation, the control unit 60 closes the hot water prohibition electromagnetic valve 54. Thereby, only the water supply from the branch water supply pipe 15 a is supplied to the water inlet of the water heater 12 through the connection pipe 16.

  Within 100 hours after entering the hot water storage / outflow prohibition operation, the entire hot water in the hot water storage tank 14 (first temperature sensor 41, second temperature sensor 42, third temperature sensor 43, fourth temperature sensor) by heat collection operation (solar heat). All the detected temperatures of 44) are monitored for 15 minutes or more in the state of 60 degrees or more (sterilization is completed). When sterilization is completed, the hot water prohibition solenoid valve 54 is opened to end the hot water storage and hot water prohibition operation. .

  If sterilization is not completed within 100 hours, the drainage solenoid valve 55 is opened, all hot water in the hot water storage tank 14 is drained with fresh water supplied from the bottom of the tank, and new water is filled in the hot water storage tank 14. Then, the hot water prohibition solenoid valve 54 is opened to end the hot water storage hot water prohibition operation.

<Detailed control of heat collection operation>
FIG. 9 shows the overall flow of the heat collection operation. When the power source of the hot water storage system 11 is turned on, the control unit 60 sets the switching valve 25 to the shut-off state (step S101). Next, it communicates with the control board 70 of the water heater 12 to obtain time information of the clock unit 89a on the water heater 12 side. If the time of the clock unit 89a is set (step S102; Yes), whether or not the time indicated by the acquired time information is within a preset allowable time zone for heat collection operation (between 4 o'clock and 19 o'clock in this example). Is determined (step S103).

  If it is in the allowable time zone for the heat collecting operation (step S103; Yes), the detected temperature of the high temperature sensor 51 provided in the heat collecting device 21 is the first temperature sensor 41 (TH1) provided near the bottom of the hot water storage tank 14. It is determined whether or not the temperature is higher than the detected temperature by a predetermined temperature (7 ° C. in this example) (step S104).

  When the temperature detected by the high temperature sensor 51 is not higher than the temperature detected by the first temperature sensor 41 (TH1) by a predetermined temperature (7 ° C. in this example) or more (step S104; No), the heat collecting device 21 and the heat exchange pipe Since there is little temperature difference with the water temperature around 18 and it is difficult to obtain a heating effect, the process returns to step S102 to inspect the heat collection operation start condition.

  If the detected temperature of the high temperature sensor 51 is higher than the detected temperature of the first temperature sensor 41 (TH1) by a predetermined temperature (7 ° C. in this example) or more (step S104; Yes), it is determined whether the high temperature sensor 51 is 85 ° C. or higher. Judgment is made (step S107). When the temperature is 85 ° C. or higher (step S107; No), the heat collection operation cannot be performed due to the problem of the heat resistance temperature of the connecting pipe made of the crosslinked polyethylene pipe, so the process returns to step S102 to check the start condition of the heat collection operation.

  If the high temperature sensor 51 is less than 85 ° C. (step S107; Yes), the heat collection operation is performed (step S108). When the heat collection operation is completed, the process returns to step S102 to check the start condition of the heat collection operation. . The control during the heat collection operation will be described with reference to FIG.

  When the clock is not set (step S102; No), or when the time indicated by the time information obtained from the clock unit 89a is not in the allowable time zone for the heat collection operation (step S103; No), the high temperature sensor 51 It is determined whether the detected temperature is 80 ° C. or higher. If it is not 80 degreeC or more (step S105; No), if the switching valve 25 exists in the heat collecting side, it will be switched to the interruption | blocking state (step S106), and it will transfer to step S102. That is, when the current time is not in the allowable time zone for the heat collecting operation, the heat medium is prevented from circulating naturally by switching the switching valve 25 to the shut-off state.

  When the detected temperature of the high temperature sensor 51 is 80 ° C. or higher (step S105; Yes), it is determined that the heat collecting operation can be allowed regardless of the time, and the process proceeds to step S107. That is, even if the clock unit 89a is not set or is set, the time may be greatly deviated. Therefore, if the temperature detected by the high temperature sensor 51 is 80 ° C. or higher, whether or not the heat collecting operation should be performed is determined by the time condition. Judgment based on temperature conditions.

  In step S107, as described above, it is determined whether or not the high temperature sensor 51 is 85 ° C. or higher (step S107). If it is 85 ° C. or higher (step S107; No), the process returns to step S102 to start the heat collecting operation. Check the conditions. If the high temperature sensor 51 is less than 85 ° C. (step S107; Yes), the heat collecting operation is performed (step S108).

  Thus, the hot water storage system 11 switches the switching valve 25 to the shut-off state when the heat collecting operation of the day ends and the heat collecting operation is outside the allowable time zone of the heat collecting operation (after 19:00). In addition, the heat medium does not naturally circulate through the heat collecting device 21 while the heat collecting operation is stopped at night, so that it is possible to prevent the night heat radiation phenomenon from occurring.

  In addition, when the time of the clock unit 89a is not set or is out of order, it is determined whether or not the heat collection operation is started based on the temperature of the high temperature sensor 51. Therefore, the time of the clock unit 89a is set. Even if it is not or crazy, the heat collecting operation can be started at an appropriate time.

  FIG. 10 shows details of the control from the start to the end of the heat collection operation (step S108 in FIG. 9).

  The control unit 60 switches the switching valve 25 to the heat collection side (open state) when starting the execution of the heat collection operation. Further, the rotational speed is set to a predetermined rotational speed (referred to as heat collection A), and the circulation pump 24 is operated (step S201).

  Two minutes have elapsed after starting the circulation of the heat medium in the heat medium circulation path 22 (step S202; No). 2 minutes is set as a time sufficient for the heat medium in the heat collecting device 21 to return to the installation location of the heat medium temperature sensor 52 in the vicinity of the hot water storage tank 14 (for removing air from the heat collecting device). ).

  When two minutes have elapsed (step S202; Yes), it is determined whether or not the temperature difference between the detected temperature of the high temperature sensor 51 and the detected temperature of the heat medium temperature sensor 52 has become 10 ° C. or less (step S203). If not (step S203; No), it is determined that one of the temperature sensors of the high temperature sensor 51 and the heat medium temperature sensor 52 has failed, and error processing is performed (step S204).

  If the temperature difference is 10 ° C. or less (step S203; Yes), the rotational speed of the circulation pump 24 is set to a predetermined rotational speed (referred to as heat collection 2) (step S205).

  Then, after waiting for 3 minutes (step S206; Yes), it is investigated whether the high temperature sensor 51 of the heat collecting apparatus 21 is 85 degreeC or more. If it is less than 85 ° C. (step S207; No), it is determined whether or not the temperature difference of each part is in an appropriate heat collection operation state (heat medium control temperature range) (step S212). Specifically, the detected temperature of the high temperature sensor 51 is in the range of + 5 ° C. to + 15 ° C. with respect to the detected temperature of the first temperature sensor 41 near the bottom of the hot water storage tank 14, and the detected temperature of the heat medium temperature sensor 52 is the first. When the temperature is 3 ° C. or more higher than the temperature detected by the one temperature sensor 41, it is determined that the temperature is within the heat medium control temperature range, and otherwise, it is determined that the temperature is outside the heat medium control temperature range.

  If it is in the heat medium control temperature range (step S212; Yes), since an appropriate heat collection operation is performed, the process proceeds to step S207, and the heat collection operation is continued as it is.

  If it is not in the heat medium control temperature range (step S212; No), it is less than the heat medium control temperature range (here, the detected temperature of the high temperature sensor 51 is less than + 5 ° C. with respect to the detected temperature of the first temperature sensor 41, or It is determined whether or not the temperature detected by the temperature sensor 52 is less than + 3 ° C. with respect to the temperature detected by the first temperature sensor 41 (step S213). If it is less than the heat medium control temperature range (step S213; Yes), it is checked whether or not the current rotational speed of the circulation pump 24 is the minimum rotational speed (referred to as heat collection 1) (step S214). (Step S214; No), in order to more efficiently receive heat in the heat collecting device 21, the rotational speed of the circulation pump 24 is lowered by one stage (Step S215), and the operation returns to Step S206 to continue the operation.

  If the current rotation speed of the circulation pump 24 is the minimum rotation speed (step S214; Yes), it is determined that heat cannot be collected efficiently due to factors such as clouding of the sky, and the circulation pump 24 is stopped. (Step S216) The heat collection operation is finished (return).

  On the other hand, when it is not less than the heat medium control temperature range (here, when the detected temperature of the high temperature sensor 51 exceeds + 15 ° C. with respect to the detected temperature of the first temperature sensor 41) (step S213; No), the circulation pump 24 It is checked whether the rotation speed is the maximum rotation speed (collecting heat 4) (step S208). If the rotation speed is not the maximum rotation speed (step S208; No), the rotation speed of the circulation pump 24 is increased by one stage (step S208). S209), the process proceeds to step S206 and the operation is continued.

  When the rotation speed of the circulation pump 24 is the maximum rotation speed (step S208; Yes), if the high temperature sensor 51 of the heat collecting device 21 is less than 80 ° C. (step S210; No), the operation returns to step S207 and continues operation. To do. If it is in the range of 80 ° C. or higher and lower than 90 ° C. (Step S210; Yes, S211; No), the temperature monitoring is continued as it is, and if it is 90 ° C. or higher (Step S211; Yes), the circulation pump 24 is stopped. (Step S216) The heat collection operation is finished (return). This is because the temperature of the heat medium has reached the heat resistance temperature of the crosslinked polyethylene pipe, so that the high temperature heat medium is retained in the heat collecting device 21 and is not circulated into the crosslinked polyethylene pipe, thereby protecting the crosslinked polyethylene pipe. Is.

  The embodiment of the present invention has been described with reference to the drawings. However, the specific configuration is not limited to that shown in the embodiment, and there are changes and additions within the scope of the present invention. Are also included in the present invention.

  In the embodiment, the switching valve 25 is switched to the shut-off state at 19:00 or later as nighttime. However, the time for determining that it is nighttime is not limited to this and may be arbitrary.

  Moreover, switching whether the switching valve 25 is in the shut-off state or the open state (heat collecting side) is not limited to the case where the time is used as a reference. Detects a situation where the heat medium naturally circulates by draft force due to the reversal of the temperature between the heat collector 21 side and the water temperature in the hot water tank 14 (the heat collector 21 side becomes lower than the hot water tank 14 side). And when such a situation arises, what is necessary is just to switch to the interruption | blocking state.

  For example, when the water temperature in the hot water storage tank 14 (preferably, the detected temperature of the first temperature sensor 41 close to the installation position of the heat exchange pipe 18) is higher than the detected temperature of the high temperature sensor 51 by a predetermined temperature or more, the shutoff state is set. You may control as follows. In addition, when the flow rate sensor detects the flow of the heat medium with the flow rate sensor provided in the heat medium circulation path 22, the switching valve 25 is set in the open state and the circulation pump 24 is stopped, the flow rate sensor is switched to the shut-off state. You may control as follows.

  In the embodiment, the system configuration in the case of additional heating with the hot water heater 12 is shown, but the heat source for additional heating is not limited to the gas water heater. Furthermore, the structure which does not provide the heat source apparatus for additional heating, such as the water heater 12, may be sufficient. That is, a system configuration in which hot water obtained by mixing hot water from the hot water storage tank 14 with hot water may be used. In the embodiment, the water-water heat exchanger 20 is provided for the solar reheating operation, the bath heat recovery operation, and the like, but the water-water heat exchanger 20 may not be provided. In this case, since the path for bypassing the heat collector 21 by the connecting pipe 26 is unnecessary, the switching valve 25 may simply switch the heat medium circulation path 22 between the open state and the closed state.

  Since the hot water heater 12 cannot perform a heating operation below the minimum heating amount, the burner 73 is not combusted when the tapping temperature exceeds the set temperature when the minimum heating amount is heated. Although it is made not to burn when filling with hot water, it may be made to burn when using a shower or hot water supply. This is because there are people who enter the tub as “donbon” (it takes time to get hot water), but when you use the shower or hot water, you can avoid the shower, This is because it can be removed. Further, since the temperature at which the shower is taken is considered to be 45 degrees or less, for example, when the hot water is filled in the bathtub, the hot water is not burned when the hot water is used at a predetermined temperature or lower, but may be burned when the hot water is used at a predetermined temperature or higher.

DESCRIPTION OF SYMBOLS 3 ... Bathtub 10 ... Hot water supply system 11 ... Hot water storage system 12 ... Hot water supply device 13 ... Hot water supply pipe 14 ... Hot water storage tank 15 ... Water supply pipe 15a ... Branch water supply pipe 16 ... Connection pipe 17 ... Mixing valve 17a ... First valve 17b ... Second valve DESCRIPTION OF SYMBOLS 18 ... Piping for heat exchange 19 ... Systurn 19a ... Water level sensor 20 ... Water-water heat exchanger 20a ... Inner pipe line 20b ... Outer pipe line 21 ... Heat collecting device 22 ... Heat-medium circulation path 22a ... First heat-medium pipe 22b 2nd heat medium pipe 22c ... 3rd heat medium pipe 22d ... 4th heat medium pipe 24 ... Circulation pump 25 ... Switching valve 25a ... 1st connection port 25b ... 2nd connection port 25c ... 3rd connection port 26 ... Connection pipe 27a ... Connection with the main body (outward)
27b: Connection with the main body (return)
DESCRIPTION OF SYMBOLS 31 ... Bath going pipe 32 ... Bath return pipe 41 ... 1st temperature sensor 42 ... 2nd temperature sensor 43 ... 3rd temperature sensor 44 ... 4th temperature sensor 46 ... Tank hot water temperature sensor 47 ... Supply water temperature sensor 48 ... Water quantity sensor 49 ... Mixing temperature sensor 51 ... High temperature sensor 52 ... Heat medium temperature sensor 53 ... Bath temperature sensor 54 ... Hot water prohibition solenoid valve 55 ... Drainage solenoid valve 56 ... Pressure relief valve 60 ... Control unit 70 ... Control board 71 ... Inlet pipe 72 ... Heat Exchanger 72a ... Hot water supply pipe 72b ... Reheating water pipe 72c ... Fin 73 ... Burner 74 ... Gas supply pipe 75 ... Gas valve 76 ... Proportional valve 77 ... Connecting pipe 78 ... Pouring solenoid valve 79 ... Water quantity servo 80 ... Hot water temperature 80 Sensor 81 ... Bypass pipe 82 ... Bypass adjustment valve 83 ... Flow rate sensor 84 ... Incoming water temperature sensor 85 ... Bath circulation pump 86 ... Running water switch 87 ... Bathing temperature sensor 88 ... Bath return temperature sensor 89 ... Operation panel (remote control)
89a ... Clock part

Claims (9)

A solar heat collector,
A hot water storage tank that stores hot water supplied to the hot spring and is replenished with water from the water supply channel;
A heat exchanger for heating the water in the hot water storage tank;
A heat medium circulation path for circulating a heat medium via the heat exchanger and the heat collector;
A circulation pump for circulating the heat medium in the heat medium circulation path;
A switching valve that is provided in the heat medium circulation path and switches between a state where the path between the heat collector and the heat exchanger is blocked and a state where the path is opened;
By setting the switching valve to the opened state and operating the circulation pump, the heat medium is circulated in the heat medium circulation path, and the circulating heat medium generates the heat obtained by the heat collector. A controller for controlling a heat collecting operation for heating the water in the hot water storage tank by discharging it with a heat exchanger;
Have
The control unit is the heat collecting device in which the heat medium naturally circulates in the heat medium circulation path and the heat on the hot water storage tank side is cooled even if the circulation pump is stopped after the heat collecting operation is finished. A hot water storage system, wherein the switching valve is in the shut-off state in order to prevent a released heat radiation phenomenon. 2. The hot water storage device according to claim 1, wherein the control unit prevents the heat dissipation phenomenon by setting the switching valve to the shut-off state at night after the heat collecting operation for one day is finished. system. A flow sensor is provided in the heat medium circulation path,
The control unit prevents the heat dissipation phenomenon by switching the switching valve to the shut-off state when the flow sensor detects circulation of a heat medium while the circulation pump is stopped. Item 2. A hot water storage system according to item 1. A first temperature sensor for detecting the temperature of the heat medium in the heat collecting device;
A second temperature sensor for detecting a water temperature around the heat exchanger;
With
The controller prevents the heat dissipation phenomenon by causing the switching valve to be shut off when the temperature detected by the first temperature sensor is lower than the temperature detected by the second temperature sensor. The hot water storage system according to claim 1. The hot water storage system according to claim 1, wherein the control unit switches the switching valve to the shut-off state when the heat collecting operation is not performed. 6. The control unit according to claim 1, wherein the control unit prohibits the heat collection operation when the time indicated by the clock unit is not within a predetermined time period for permitting the heat collection operation. Hot water storage system. If the temperature of the heat medium in the heat collecting device is equal to or higher than the predetermined temperature even when the timepiece is not set or the time indicated by the timepiece is not in the permitted time zone, the control unit The hot water storage system according to claim 6, wherein the heat collection operation is started. The heating medium circulation path comprises a cross-linked polyethylene pipe part;
The said control part prohibits the said heat collection operation | movement as long as the temperature of the heat medium in the said heat collecting apparatus is more than the heat-resistant temperature of the said crosslinked polyethylene pipe. Hot water storage system described in one. The said switching valve forms the said interruption | blocking state by switching the said heat-medium circulation path | route to the circulation path | route which detoured the said heat collecting apparatus. The one thing of Claim 1 thru | or 8 characterized by the above-mentioned. Hot water storage system.

Images