JP5901920B2 - Solar heat utilization system - Google Patents

Description

  The present invention relates to a solar heat utilization system in which water in a hot water storage tank is heated by solar heat and used for hot water.

  There is a system in which the temperature in the hot water storage tank is raised by exhaust heat from solar heat or power generation equipment, and used for hot water supply or bath pouring. For example, in a fuel cell type power generation device, since cooling of the power generation device is essential for power generation, it is generally performed to raise the temperature of hot water in a hot water storage tank with exhaust heat from the power generation device.

  However, when the temperature of the hot water in the hot water storage tank rises, the heat of the power generation device becomes difficult to move to the hot water in the hot water storage tank, and the cooling efficiency of the power generation device decreases, making it impossible to continue power generation. So, if the hot water in the hot water storage tank is hot and the automatic hot water filling of the bath is reserved, even before the reservation time, the hot water in the hot water storage tank is used to fill the bathtub. There has been proposed a hot water supply system that replenishes hot water in a hot water storage tank to lower the temperature of the hot water in the tank and allows the power generator to be cooled (see, for example, Patent Document 1).

  In addition, a heat pump water heater is proposed that mixes the hot water in the middle and hot water of the hot water storage tank with a pump to lower the temperature of the hot water in the middle and low water on average, and hot water is stored in the upper part of the hot water storage tank. (For example, see Patent Document 2).

JP 2006-029655 A JP 2006-343056 A

  In a solar heat utilization system that collects solar heat and heats the water in the hot water storage tank with that heat, when the temperature of the hot water in the hot water storage tank rises, the heat recovery efficiency of the solar heat in the heat collecting device decreases and the solar heat becomes effective. It becomes unavailable.

  In addition, the technique disclosed in Patent Literature 1 cannot be used unless automatic bath filling is reserved. Moreover, since hot water cannot be poured when there is already a set water level in the bathtub, the temperature of the hot water in the hot water storage tank cannot be lowered. In addition, since the hot water is poured to the set water level at a time, a large amount of hot water in the hot water storage tank is used, and it becomes easy to run out of hot water.

  The present invention is intended to solve the above-described problem, and an object of the present invention is to provide a solar heat utilization system that can suppress the occurrence of a situation in which the hot water storage tank can no longer store heat and the utilization efficiency of solar heat decreases. It is said.

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

[1] A hot water storage tank in which a water supply pipe is connected to the inlet, and a pipe connected to the bathtub via a pouring valve controlled to open and close is connected to the outlet;
A heating device for raising the temperature of the water in the hot water storage tank with heat obtained by a heat collecting device for collecting solar heat;
A control unit for controlling a heat collecting operation for collecting heat obtained by the heat collecting device;
Have
The heat collecting operation includes a heat collecting operation for raising the temperature of the water in the hot water storage tank by the heating device by the heat obtained by the heat collecting device, and the temperature of the hot water in the hot water storage tank is increased, thereby reducing the heat recovery efficiency. A heat evacuation operation to move the heat in the hot water storage tank to the hot water in the bathtub when
As one of the heat evacuation operations, the controller opens the pouring valve so that the hot water in the hot water storage tank is transferred to the bathtub on the condition that the temperature of the hot water in the hot water storage tank is at least a predetermined temperature. A solar heat utilization system characterized by performing a first control to be poured into the water.

  In the above invention, on the condition that the temperature of the hot water in the hot water storage tank becomes equal to or higher than the predetermined temperature and the heat recovery efficiency (utilization efficiency) of solar heat is lowered, the hot water supply valve opens and the hot water in the hot water storage tank is transferred to the bathtub. The first control for pouring is performed. When hot water is discharged from the outlet of the hot water storage tank due to the pouring, the water supply is replenished by that amount, and the temperature of the hot water in the hot water storage tank is lowered to recover the heat recovery efficiency. In addition, you may add other requirements, for example, the automatic hot water filling of the bath is reserved, the bathtub water level is below a setting water level, etc. as execution start conditions of 1st control.

[2] The inlet is provided at a lower portion of the hot water storage tank,
The outlet is provided in the upper part of the hot water storage tank,
The heating device heats hot water in the lower part of the hot water storage tank,
The said control part determines whether the temperature of the hot water of the lower part of the said hot water storage tank is more than the said predetermined temperature. The solar-heat utilization system as described in [1] characterized by the above-mentioned.

  In the said invention, a heating apparatus heats the hot water of the lower part of a hot water storage tank, and a control part judges the fall of heat recovery efficiency based on the water temperature of the lower part of a hot water storage tank. Also, water is supplied from the lower part of the hot water storage tank, and hot water comes out from the upper outlet. In this configuration, when hot water is poured in the first control, the water temperature around the heating device provided in the lower part of the hot water storage tank is lowered, but hot water is secured in the upper part of the hot water storage tank where the hot water outlet is located. Can be prepared.

[3] When the temperature of the hot water in the hot water storage tank is lowered to a second temperature lower than the predetermined temperature, the control unit stops the first control and intermittently performs pouring by the first control little by little. solar heating system according to [1] or [2], wherein the performed manner.

  In the above invention, the first control (pouring) is started when the temperature of the hot water in the hot water tank reaches the first temperature, and the first control is stopped when the temperature drops to the second temperature. That is, the pouring by the first control is intermittently performed little by little.

[4] A bathtub water circulation path in which one end is connected to a bathtub water intake opening opened in the bathtub and the other end is connected to a bathtub water return opening opened in the bathtub and the bathtub water can be circulated by a pump. A second heating device that is provided in the middle and heats hot water in the bathtub water circulation path using hot water in the hot water storage tank as a heat source;
The controller, as one of the heat evacuation operations, is provided that at least the temperature of the hot water in the hot water storage tank is equal to or higher than a predetermined temperature, and the water level in the bathtub reaches the bathtub water intake port. And the second water heating device acts to heat the hot water in the hot water storage tank and heat the hot water in the hot water storage tank to perform the second control. The solar heat utilization system according to any one of claims 1 to 3.

  In the said invention, the 2nd heating apparatus which uses the hot water in a hot water storage tank as a heat source on the condition that the temperature of the hot water in a hot water storage tank is more than predetermined temperature and the water level of the bathtub has reached the bathtub water intake port The second control for heating the hot and cold water in the bathtub is performed. In the second control, the heat of the hot water in the hot water storage tank moves to the bathtub water, and the temperature of the hot water in the hot water storage tank decreases. In addition, other requirements as the execution start condition of the second control, for example, automatic bath filling is reserved, the bath water level has reached the set water level, the bath water temperature is lower than the set temperature, etc. May be added.

[5] The control unit performs the first control on the condition that the water level in the bathtub is less than the set water level, and performs the second control when the water level in the bathtub has reached the set water level. The solar-heat utilization system as described in [4] characterized by the above-mentioned.

  In the above invention, if the water level of the bathtub is lower than the set water level, the first control for pouring hot water in the hot water storage tank is performed, and when the water level of the bathtub has already reached the set water level, the hot water in the hot water tank is used as the heat source. 2nd control which heats the hot water in a bathtub with the 2nd heating device to perform is performed.

[6] The heating device includes the heat collecting device, a heat exchanger for heating the hot water in the hot water storage tank, and a heat medium fluid formed between the heat collecting device and the heat exchanger. A circulation path, and a circulation pump for circulating a heat medium fluid between the heat collector and the heat exchanger through the circulation path,
In the second heating device, a first heat exchange pipe is connected in the middle of the circulation path, and a second heat exchange pipe that exchanges heat with the first heat exchange pipe is connected in the middle of the bathtub water circulation path. Have a heat exchanger,
A switching valve for switching the circulation path to a normal path that passes through the heat collector and a bypass path that bypasses the heat collector;
In the second control, the control unit sets the circulation path to the bypass path with the switching valve to operate the circulation pump at full speed, and the temperature of the hot water in the hot water storage tank is lower than the predetermined temperature. The solar heat utilization system according to [4] or [5], wherein the second control is stopped when the temperature falls to two temperatures.

[7] The outlet of the hot water storage tank is connected to a pipe that has the pouring valve and leads to the water inlet of a bath water heater having a function of pouring water into the bathtub,
The controller according to any one of [1] to [6], wherein in the first control, the bath water heater is instructed to perform a pouring operation without heating. Solar heat utilization system.

  In the said invention, the bath water heater which can pour into a bathtub is connected to a back | latter stage. In the first control, the control unit instructs the bath water heater to pour hot water into the bathtub without heating.

[8] The bath water heater has a function of circulating hot water in the bathtub with the pump through the bathtub water circulation path to replenish the hot water in the bathtub,
In the second control, the control unit instructs the bath water heater to operate the pump without heating. Citation is given in any one of [4] to [6]. [7] The solar heat utilization system according to [7].

  In the said invention, the bath water heater which has the function of reheating a bath is connected to a back | latter stage. In the second control, the control unit instructs the bath water heater to operate the reheating pump without heating. Thereby, bathtub water circulates in the bathtub water circulation path which passes along the 2nd heating device, and bathtub water is heated.

[8] The solar heat utilization system according to [7] or [8], including the bath water heater.

  According to the solar heat utilization system which concerns on this invention, generation | occurrence | production of the situation which becomes unable to store heat any more in a hot water storage tank is suppressed, and the utilization factor of solar heat can be raised.

It is explanatory drawing which shows schematic structure of the hot water supply system containing the solar-heat utilization system of this invention. It is explanatory drawing which shows schematic structure of a bath water heater. It is explanatory drawing which shows the path | route of the hot water in a hot water supply driving | operation. It is explanatory drawing which shows the circulation path of the heat medium in heat collection operation | movement. It is explanatory drawing which shows the path | route of the hot water in 1st heat evacuation operation | movement. It is explanatory drawing which shows the circulation path | route of the hot water and heat medium in 2nd heat evacuation operation | movement. It is a flowchart which shows the control in heat collection driving | operation. It is explanatory drawing which shows the path | route of the heat medium and bathtub water in the case of performing heat collecting operation | movement and 2nd heat evacuation operation | movement in parallel.

  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 solar heat utilization system (hereinafter referred to as a hot water storage system) of the present invention. The hot water supply system 10 includes a hot water storage system 11 and a bath water heater 12.

  The hot water storage system 11 includes a hot water storage tank 14 for storing hot water heated using sunlight, and supplies hot water from the hot water storage tank 14 to the water supply port of the bath water heater 12. The bath water heater 12 fulfills the function of heating the hot 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 using sunlight to suppress heating by the bath water heater 12 (hereinafter referred to as “follow-up heating”), and to supply hot water with energy saving. to 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. A terminal end of the water supply pipe 15 is connected to the bottom pipe connection port (inlet). One end of the connection pipe 16 is connected to the pipe connection port (exit) of the ceiling, and the other end of the connection pipe 16 is connected to the water supply port of the bath 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 bath 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 connected to the connecting pipe 16 on the outlet side (bath water heater 12 side) of the mixing valve 17, and the temperature of hot water after mixing by the mixing valve 17 is further downstream (bath water heater 12 side). A mixed temperature sensor 49 is provided to detect the above.

  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. In addition, the cistern 19 is a tank that is open to atmospheric pressure, and removes air mixed in the heat medium circulation path 22 and absorbs volume fluctuation due to expansion and contraction of the heat medium. The heat medium outlet is located at the bottom of the cistern 19, and the heat medium inlet from the heat exchange pipe 18 is provided to some extent above the outlet. The opening 19b for opening to the atmosphere is provided in the upper part (above the assumed maximum water level) of the cis turn 19, and a tube 19c extending downward and having an open end is connected to the outside of the opening 19b for opening to the atmosphere. ing. In addition, the cistern 19 includes a water level sensor 19a that detects an 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. One pipe line (in the drawing, an inner pipe line (first heat exchange pipe) 20a) of the water-water heat exchanger 20 is inserted and connected in the middle of the heat medium circulation path 22.

  A circulation pump 24 is provided in the middle of the third heat medium pipe 22 c from the outlet side of the inner pipe 20 a of the water-water heat exchanger 20 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 switching valve 25 allows the first connection port 25a and the second connection port 25b to communicate with each other and the third connection port 25c to close, and the first connection port 25a and the third connection port 25c to communicate with each other. It switches to the 2nd state which closed connection port 25b.

  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 connecting pipe of a part from the main body side connection part 27a of the hot water storage system 11 to the heat collecting device 21 and a part of the third heat medium pipe 22c returning to the main body side connecting part 27b of the hot water storage system 11 are connected. Cross-linked polyethylene pipes are used for the piping. 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 bath water heater 12 heats the hot water supplied from the hot water storage system 11 through a connection pipe 16 connected to the water supply port to a set temperature and discharges the hot water to the hot water supply pipe 13, and sets the hot water supplied from the water supply port to the bath. It has a hot water filling function (hot water pouring function) for pouring hot water into the bathtub 3 by heating to a temperature and the like, and a reheating function for chasing hot water in the bathtub 3.

  The recirculation circulation path for circulating hot water during reheating includes a bath return pipe 32 for taking hot water from the bathtub 3 into the bath water heater 12, a pipe passing through the heat exchanger in the bath water heater 12, and a heat exchanger. The hot water heated after that is composed of a bath outlet pipe 31 that sends out hot water to the bathtub 3. The bath outlet pipe 31 reaches the bathtub 3 through the other pipe line (outer pipe line (second heat exchange pipe) 20b) of the water-water heat exchanger 20 on the way.

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

  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 transmits and receives necessary information from a common remote controller (hereinafter referred to as a common remote controller) for the hot water storage system 11 and the bath water heater 12, and the control base 70 of the bath water heater 12 is also a common remote controller. Send and receive necessary information. Here, the control unit 60 acquires information on the set temperature set by the common remote controller, information indicating whether or not the bath water heater 12 is instructed to perform a reheating operation, and the like from the common remote controller. In addition, 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 common remote controller 12. It transmits using the signal etc. which are used at the time of maintenance. The control board 70 of the bath water heater 12 receives information indicated by these signals from the above-described common remote controller.

  FIG. 2 shows a schematic configuration of the bath water heater 12. The bath water heater 12 includes a hot water supply water pipe 72a in which a water inlet pipe 71 is connected to the outlet side and a hot water supply pipe 13 to the outlet side, and a bath outlet pipe 31 on the outlet side, and a bath return pipe 32 to the inlet side. A can-two-water channel heat exchanger 72 provided with a reheating water pipe 72b is provided. The starting end of the water intake pipe 71 is a water supply port 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. By the bypass pipe 81 and the bypass adjustment valve 82, even if hot water having a temperature higher than the set temperature is produced in the hot water supply water pipe 72a, the hot water having the set temperature is produced by mixing with the water fed from the water inlet pipe 71. . For this purpose, a hot water supply pipe outlet temperature sensor 91 for measuring the hot water supply pipe 72a outlet temperature is provided.

  Then, the bypass adjustment valve 82 is adjusted so that the hot water temperature set in the common remote controller matches the measured value of the hot water temperature sensor 80 while referring to the hot water supply pipe outlet temperature sensor 91 and the incoming water temperature described later. In addition, the inlet pipe 71 upstream of the branch 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 water 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 hot water in the bathtub 3 through the recirculation circulation path (bath return pipe 32, reheating water pipe 72b, bath return 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 bath water heater 12 has are connected to the control board 70.

  Furthermore, an operation panel (common remote controller) 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.

  The control base 70 of the bath water heater 12 is configured so that the amount of combustion of the burner 73 and the bypass adjustment valve 82 are adjusted so that hot water at the hot water supply set temperature set by the user on the operation panel 89 is discharged in the hot water supply operation. Control the opening.

  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. Thereby, the hot water in the bathtub 3 is taken into the bath 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 going pipe 31.

  The bath water heater 12 can perform a pouring operation (a pouring operation without combustion) without burning the burner 73 in accordance with an instruction from the hot water storage system 11. In addition, an operation for operating the bath circulation pump 85 without burning the burner 73 (a reheating operation without combustion) can be executed in accordance with an instruction from the hot water storage system 11.

  The burner 73 of the bath water heater 12 cannot be burned below a predetermined minimum heating amount (minimum number). Therefore, the control base 70 of the bath 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 discharging 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.

<Hot water supply operation>
FIG. 3 shows a schematic operation of the hot water supply operation. In FIG. 3, 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, the hot water from the hot water storage tank 14 and the water supplied from the branch water supply pipe 15a are mixed by the mixing valve 17 and supplied to the water supply port (water intake pipe 71) of the bath water heater 12. The bath water heater 12 heats the supplied water as needed and discharges it to the hot water supply pipe 13.

  That is, when there is a predetermined amount or more of hot water having a temperature higher than the set temperature by a first temperature (margin temperature considering the temperature drop in the middle, for example, 2 ° C.) or more than the set temperature (with hot water), the set temperature + The mixing ratio of the mixing valve 17 is controlled so that hot water at the first temperature is sent from the outlet side of the mixing valve 17 to the bath water heater 12. In this case, the bath water heater 12 determines that combustion in the own apparatus is unnecessary, and hot water supplied from the hot water storage system 11 side is discharged to the hot water supply pipe 13 without heating. For example, the above operation is performed when the third temperature sensor 43 provided in the hot water storage tank 14 detects a temperature equal to or higher than (set temperature + predetermined temperature).

  On the other hand, if hot water having a temperature higher than the preset temperature by a first temperature (margin temperature considering the temperature drop in the middle) or more than a predetermined amount does not exist in the hot water storage tank 14 (hot water shortage), follow-up heating in the bath water heater 12 The mixing ratio of the mixing valve 17 is adjusted so that hot water having a temperature lower than the second temperature by a second temperature or more is sent from the outlet side of the mixing valve 17 to the bath water heater 12 so that hot water having a set temperature is discharged. Control. When hot water having a temperature equal to or lower than the set temperature-second temperature is supplied, the bath water heater 12 always burns the burner 73.

  For example, when the temperature of the hot water in the hot water storage tank 14 is lower than the set temperature by a second temperature or more, the hot water in the hot water storage tank 14 is directly supplied to the bath water heater 12 without mixing the water supplied from the branch water supply pipe 15a by the mixing valve 17. send. When the hot water in the hot water storage tank 14 is higher than the set temperature + second temperature but lower than the set temperature + first temperature, the hot water from the hot water storage tank 14 is mixed with hot water from the branch water supply pipe 15a by the mixing valve 17. The hot water whose temperature has been lowered to the preset temperature minus the second temperature is sent to the bath water heater 12. Thus, additional heating is performed in the bath water heater 12. Moreover, even if additional heating is performed, the tapping temperature does not exceed the set temperature.

  In the hot water supply operation, various controls for stabilizing the hot water temperature at the set temperature may be further added. For example, when the heat exchanger 72 of the bath water heater 12 is cold (so-called cold start), the hot water storage tank 14 has a predetermined amount or more of hot water having a temperature equal to or higher than the (set temperature + first temperature). Even if there is, a cold start measure for controlling the temperature of the hot water sent from the outlet side of the mixing valve 17 to the bath water heater 12 to (set temperature−second temperature) or less so that the bath water heater 12 performs additional heating. Add. That is, without additional heating, the cooled heat exchanger 72 is deprived of heat, and the hot water temperature decreases accordingly. In addition, since the temperature of the cooled heat exchanger 72 is gradually raised by the hot water passing through the heat exchanger 72, the hot water temperature does not easily rise, and it takes a long time for the hot water to reach the set temperature. With this cold start measure, it becomes possible to discharge hot water at a preset temperature from the beginning.

<Heat collection operation>
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.

  In the heat collection operation, the heat collection operation for heating the water in the hot water storage tank 14 using the heat obtained from sunlight by the heat collecting device 21, and the temperature of the hot water in the hot water storage tank 14 rises and the heat recovery efficiency decreases. In this case, the heat evacuation operation moves the hot water in the hot water storage tank 14 to the hot water in the bathtub 3. The heat evacuation operation includes a first heat evacuation operation for pouring hot water from the hot water storage tank 14 into the bathtub 3, and a second heat evacuation operation for moving the heat of the hot water storage tank 14 to the bathtub water through the water-water heat exchanger 20. There is.

  FIG. 4 shows an outline of the heat collecting operation performed by the hot water storage system 11. The hot water storage tank 14 receives supply of water from a water supply pipe 15 connected to a pipe connection port (inlet) at the bottom, and is usually in a full state. During the heat collecting operation, the control unit 60 drives the circulation pump 24 after setting the switching valve 25 in a state where the first connection port 25a and the second connection port 25b communicate with each other and the third connection port 25c is closed. .

  In FIG. 4, 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 around the heat exchange pipe 18 in the hot water storage tank 14 is lower than the temperature of 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. Thus, the water in the hot water storage tank 14 is heated.

  The heat exchange pipe 18 is located below the hot water storage tank 14. In addition, since water is supplied from the bottom of the hot water storage tank 14 and the hot water flows out from the pipe connection port (exit) of the ceiling of the hot water storage tank 14 to the connection pipe 16, the water temperature in the hot water storage tank 14 is lower at the bottom and closer to the ceiling. The temperature gradient is high.

  If the heat collection operation continues for a long time without the hot water in the hot water storage tank 14 being used for hot water or the like, the water temperature around the heat exchange pipe 18 below the hot water storage tank 14 rises, and the heat medium flowing in the heat exchange pipe 18 The temperature difference with the water around the heat exchange pipe 18 is reduced, and the heating efficiency of the hot water in the hot water storage tank 14 by the heat exchange pipe 18 is lowered. In other words, since the temperature of the heat medium does not decrease much when passing through the heat exchange pipe 18, the temperature of the heat medium sent to the heat collector 21 via the cistern 19 becomes relatively high, and the heat collector 21 The heat recovery efficiency of solar heat (utilization efficiency of solar heat) decreases.

  Accordingly, the hot water storage system 11 performs the first heat evacuation operation of pouring hot water in the hot water storage tank 14 into the bathtub 3 if the water level in the bathtub 3 satisfies conditions such as the water level being lower than the set water level and can be poured into the bathtub 3. I do. Further, when there is hot water at the set water level in the bathtub 3 and no more hot water can be poured, a second heat evacuation operation is performed to move the hot water in the hot water storage tank 14 to the bathtub water via the water-water heat exchanger 20. To do.

<First heat escape operation>
FIG. 5 shows a path through which hot water flows in the first heat evacuation operation by a bold line. The first heat evacuation operation is performed in parallel with the above-described heat collection operation, or the heat collection operation during the first heat evacuation operation is stopped. In the first heat evacuation operation, the control unit 60 of the hot water storage system 11 opens the hot water solenoid valve 78 in a state in which the combustion (heating operation) of the burner 73 is stopped with respect to the bath water heater 12, that is, no combustion. Instruct the pouring operation.

  When the hot water solenoid valve 78 is opened, hot water in the upper part of the hot water storage tank 14 is supplied to the bath water heater 12 through the connection pipe 16 and the mixing valve 17. Part of this hot water passes through the heat exchanger 72 in the bath water heater 12, and the remaining hot water passes through the bypass pipe 81 to the connecting pipe 77, passes through the pouring solenoid valve 78, and then goes to the bath outlet pipe 31 and the bath. The hot water is poured into the bathtub 3 in two paths of the return pipe 32.

  In the first heat evacuation operation, the mixing ratio of the mixing valve 17 is set so that the temperature of the hot water poured into the bathtub 3 becomes the set temperature of the bath. Here, the mixing ratio of the mixing valve 17 is controlled so that the temperature at the outlet side of the mixing valve 17 becomes the set temperature of the bath + 2 ° C. in consideration of the temperature drop when passing through the connecting pipe 16 and the heat exchanger 72. .

  When the hot water in the upper part of the hot water storage tank 14 is used for pouring, cold water is replenished to the lower part of the hot water storage tank 14 from the water supply pipe 15 and the water temperature around the heat exchange pipe 18 is lowered. Thereby, the heat recovery efficiency (solar heat utilization efficiency) of solar heat in the heat collecting operation is improved and recovered.

  The first heat evacuation operation ends when the solar heat recovery efficiency in the heat collection operation is restored. And if the heat recovery efficiency of solar heat falls again, the 1st heat escape operation will be started. Therefore, pouring into the bathtub 3 by the first heat evacuation operation is performed little by little intermittently. Thus, since the hot water pouring into the bathtub 3 by the first heat evacuation operation is intermittently carried out little by little, it is possible to maintain a state in which a sufficient amount of hot water is accumulated in the upper part of the hot water storage tank 14, and the next by the user. It is possible to meet the demand for hot water.

<Second heat escape operation>
FIG. 6 shows the heat medium circulation path and the bath water circulation path in the second heat evacuation operation. In FIG. 6, the path through which the heat medium (water) circulates in the second heat evacuation operation is indicated by a thick line, and the circulation path of the bath water is indicated by a 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.

  In the second heat evacuation operation, the control unit 60 sets the switching valve 25 in a state where the first connection port 25a and the third connection port 25c communicate with each other and the second connection port 25b is closed, and then the circulation pump 24 is turned on. To drive. Thereby, the heat medium bypasses the heat collecting device 21 and circulates in a bypass circulation path passing through the water-water heat exchanger 20 and the hot water storage tank 14. In addition, the bath water heater 12 is instructed to drive the bath circulation pump 85 in a state where combustion (heating operation) is stopped (instruction of a reheating operation without combustion). As a result, the bathtub water circulates through the recirculation circulation path that passes through the outer conduit 20 b of the water-water heat exchanger 20.

  The second heat evacuation operation has operating conditions such as the presence of hot water of a predetermined amount (predetermined water level) or more in the bathtub 3 and the temperature of the hot water in the bathtub 3 being a set temperature or lower. In the second heat escape operation, in the water-water heat exchanger 20, heat is transferred from the heat medium circulating through the inner pipe line 20a to the bath water circulating through the outer pipe line 20b, and the heat exchange pipe 18 The hot water in the hot water storage tank 14 moves to the heat medium. That is, using the heat medium, the hot water in the lower part of the hot water storage tank 14 moves to the bath water, the temperature of the hot water in the hot water tank 14 decreases, and the temperature of the hot water in the lower part of the hot water storage tank 14 decreases.

  In the second heat evacuation operation, the heat medium circulation path 24 is switched to a detour circulation path that bypasses the heat collecting device 21, and the heat medium circulation pump 24 is operated at full speed. When the bath circulation pump 85 of the bath water heater 12 that circulates the bath water is variable in speed, the bath circulation pump 85 is also operated at full speed.

  Since the cistern 19 is open to the atmosphere, if the circulation path of the heat medium is shortened by bypassing the heat collecting device 21, the pressure loss in the circulation path is reduced, the amount of heat medium transported by the circulation pump 24 is increased, and the lower part of the hot water storage tank 14. The efficiency of lowering the temperature of hot water is improved. However, since the heat medium does not flow through the heat collecting device 21 by bypassing the heat collecting device 21, the temperature of the heat medium stopped in the heat collecting device 21 is increased due to solar heat. As described above, the connecting pipe that connects the heat collector 21 and the main body of the hot water storage system 11 has a heat-resistant temperature of 90 ° C. to 95 ° C. Therefore, before the heat medium that is retained in the heat collector 21 exceeds this heat-resistant temperature. It is necessary to return the circulation path to the normal state so that the heat medium circulates through the heat collector 21.

  Therefore, the circulation pump 24 that circulates the heat medium and the bath circulation pump 85 of the bath water heater 12 that circulates the bath water are operated at full speed. Thereby, since the amount of heat transfer per unit time from the hot water in the hot water storage tank 14 to the bathtub water increases, the temperature of the hot water in the lower part of the hot water storage tank 14 is efficiently reduced in a short time. As a result, the second heat evacuation operation is completed in a short time, and the period during which the heat medium circulates around the heat collecting device 21 can be shortened.

  Next, the overall operation flow including the heat collection operation and the heat evacuation operation will be described.

  FIG. 7 shows an operation flow of the entire heat collecting operation. Here, the water temperature in the lower part of the hot water storage tank 14 is determined based on the temperature detected by the second temperature sensor 42. If the temperature detected by the second temperature sensor 42 is less than 40 ° C. (step S101; Yes), the hot water storage system 11 continues the normal heat collecting operation shown in FIG. 4 (step S102).

  When the temperature detected by the second temperature sensor 42 is 40 ° C. or higher (step S101; No), it is determined whether or not the water level in the bathtub 3 is lower than the set water level (step S103). The control unit 60 of the hot water storage system 11 requests the bath water heater 12 to detect the water level in the bathtub 3 and the temperature of the bathtub water, and receives the response from the bath water heater 12 to thereby detect the water level in the bathtub 3. Recognize the temperature of bathtub water.

  If the water level in the bathtub 3 is less than the set water level (step S103; Yes), the first heat evacuation operation shown in FIG. 5 is performed. Specifically, the bath water heater 12 is requested to open the hot water solenoid valve 78 without burning the burner 73. In addition, the mixing valve 17 is controlled so that the hot water temperature on the outlet side of the mixing valve 17 becomes, for example, the set temperature of the bath + 2 ° C. By performing the pouring operation by the first heat evacuation operation, the lower portion of the hot water storage tank 14 is supplemented with water supply, and the temperature of the hot water in the lower portion of the hot water storage tank 14 is lowered.

  After the start of the first heat evacuation operation, the control unit 60 determines whether or not the temperature detected by the second temperature sensor 42 is equal to or lower than a predetermined temperature lower than 40 ° C. (here 35 ° C.) (step S105). Whether the water level of the bathtub 3 reaches the set water level (step S106) and the detected temperature of the second temperature sensor 42 is 35 ° C. or lower (step S105; Yes), or the water level of the bathtub 3 Reaches the set water level (step S106; Yes), the first heat evacuation operation is stopped (step S107). Specifically, it instructs the bath water heater 12 to close the pouring solenoid valve 78, that is, stop the pouring operation without combustion. Then, it returns to step S101 and continues a process.

  As described above, when the temperature detected by the second temperature sensor 42 reaches 40 ° C., the first heat evacuation operation is started. When the temperature is lowered to 35 ° C., the first heat evacuation operation is stopped. It is repeated intermittently and poured into the bathtub 3 little by little. Therefore, the hot water in the upper part of the hot water storage tank 14 does not decrease in a large amount in a short time due to the first heat evacuation operation, and the hot water in the upper part of the hot water storage tank 14 is secured sufficiently, The temperature of the hot water can be lowered to prevent a decrease in solar heat recovery efficiency.

  When the water level of the bathtub 3 has reached the set water level (step S103; No), it is checked whether or not the temperature of the hot water in the bathtub 3 is lower than the set temperature of the bath (step S108). When the temperature of the hot water in the bathtub 3 is lower than the set temperature of the bath (step S108; Yes), the heat medium circulation path is switched to a bypass circulation path that bypasses the heat collecting device 21 (step S109), and FIG. The second heat evacuation operation shown in (2) is started (step S110). Specifically, the bath water heater 12 is instructed to drive the bath circulation pump 85 in a state where combustion (heating operation) is stopped. The heat medium circulation pump 24 is driven at full speed. If the bath circulation pump 85 of the bath water heater 12 is variable in speed, the bath water heater 12 is instructed to operate the bath circulation pump 85 at full speed.

  Thereby, the heat of the hot water in the lower part of the hot water storage tank 14 moves to the bathtub water in the water-water heat exchanger 20, and the temperature of the hot water in the lower part of the hot water storage tank 14 is lowered.

  After the start of the second heat evacuation operation, the control unit 60 monitors whether or not the temperature detected by the second temperature sensor 42 is equal to or lower than a predetermined temperature lower than 40 ° C. (here, 35 ° C.) (step S111). ). When the detected temperature of the second temperature sensor 42 becomes 35 ° C. or lower (step S111; Yes), the second heat evacuation operation is stopped. (Step S107). Specifically, the bath water heater 12 is instructed to stop the bath circulation pump 85. Furthermore, the circulation path of the heat medium is returned to the normal circulation path via the heat collecting device 21, and the speed control of the circulation pump 24 is returned to the normal control. (Step S113). Thereafter, the process proceeds to step S101 to continue the processing.

  When the temperature of the hot water in the bathtub 3 has reached the set temperature of the bath (step S108; No), a normal heat collecting operation is performed (step S102). In this case, since neither the first or second heat evacuation operation can be performed, the solar heat recovery efficiency is low, but the solar heat can be stored in the hot water in the hot water storage tank 14 by performing the heat collection operation.

  Note that when the detected water temperature of the second temperature sensor 42 or the like reaches a specified upper limit temperature (for example, 80 ° C.), the heat collection operation itself (the process of FIG. 7) is stopped.

  As described above, even when the bathtub 3 has already reached the set water level and cannot be poured, the temperature of the hot water in the lower part of the hot water storage tank 14 can be lowered by the second heat evacuation operation for chasing the bathtub water. A decrease in heat recovery efficiency can be prevented.

  In the present invention, even when the temperature of the hot water in the hot water storage tank 14 rises during the heat collecting operation and it becomes difficult to store heat further, the first heat evacuation operation for pouring hot water in the hot water storage tank 14 into the bathtub 3 is performed. Alternatively, the temperature of the hot water in the hot water storage tank 14 is lowered by performing a second heat evacuation operation for raising the temperature of the bathtub water with the heat of the hot water in the hot water storage tank 14. Decline can be prevented. In other words, the first and second heat evacuation operations are operations using the bathtub 3 as a solar heat storage place, and the bathtub 3 plays a sub-tank role of the hot water storage tank 14.

  Next, a bath heat recovery operation for returning the heat evacuated to the bathtub 3 to the hot water storage tank 14 will be described.

  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. That is, it is an operation for returning the heat evacuated to the sub tank (tub) to the hot water storage tank 14.

  The hot water and heat medium circulation paths in the bath heat recovery operation are the same as those in the second heat evacuation operation shown in FIG. That is, in the bath heat recovery operation, the control unit 60 sets the switching valve 25 in a state where the first connection port 25a and the third connection port 25c communicate with each other and the second connection port 25b is closed, and then the circulation pump 24 Drive. 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 bath 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.

  The bath heat recovery operation is performed under the condition that the water temperature in the hot water storage tank 14 (for example, the temperature detected by the first temperature sensor 41) is lower than the water temperature in the bathtub 3, and the water-water heat exchanger 20 Heat is transferred from the bathtub water passing through the pipe line 20b to the heat medium passing through the inner pipe line 20a, and this heat is transferred to the water in the hot water storage tank 14 at the portion of the heat exchange pipe 18, whereby Water is heated.

  More specifically, in 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, operation stops. The time limit is based on the durability of the bath circulation pump 85.

  Thus, in the bath heat recovery operation, the heat retreated to the bathtub 3 as a sub tank can be returned to the hot water storage tank 14 as necessary. For example, if the bath heat recovery operation is performed when the heat collection operation of the day ends at night and the automatic operation of the bath is turned off, the burden of the heat collection operation on the next day is reduced.

  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.

  For example, during the first heat evacuation operation, the heat collection operation may be stopped, or the heat collection operation may be performed in parallel.

  In the embodiment, during the execution of the second heat evacuation operation, the circulation path of the heat medium is switched to the bypass circulation path. However, the circulation path of the heat medium is set in the same manner as the heat collection operation. You may comprise so that heat collection operation | movement may be performed in parallel during execution of heat evacuation operation | movement.

  FIG. 8 shows the paths of the bath water and the heat medium when the heat collection operation and the second heat evacuation operation are executed in parallel. In the figure, the path through which the heat medium (water) circulates in the heat collecting operation is indicated by a thick line, and the circulation path of the bathtub water is indicated by a thick broken line. If the heat collecting operation is executed in parallel, the heat medium does not stay in the heat collecting device 21, so that the second heat evacuation operation can be continued and the number of switching of the switching valve 25 can be reduced.

  In the embodiment, the temperature detected by the second temperature sensor 42 is used as a criterion for determining whether or not to execute the first heat evacuation operation and the second heat evacuation operation. Other sensors may be used as long as they detect the temperature of the lower hot water. It should be noted that other criteria may be used as a criterion for determining whether or not to execute the first heat evacuation operation and the second heat evacuation operation as long as it is possible to determine a decrease or recovery in solar heat recovery efficiency.

  In the embodiment, the start condition of the heat evacuation operation is that the detected temperature of the second temperature sensor 42 is 40 ° C. or more, and the stop of the heat evacuation operation is that the detected temperature of the second temperature sensor 42 is 35 ° C. or less. However, these temperatures are merely examples, and may be set appropriately.

  The temperature at which the end of the second heat evacuation operation is determined may be a temperature that is relatively close to 40 ° C., which is the starting condition for the second heat evacuation operation, such as 38 ° C. That is, since the temperature of the heat medium stopped in the heat collecting device 21 is increased while switching to the bypass circulation path, the second temperature is set so that the temperature does not exceed the heat resistance temperature of the connecting pipe made of cross-linked polyethylene. The temperature difference between the threshold temperature for determining the stop of the heat evacuation operation and the threshold temperature that is the start condition of the second heat evacuation operation is made smaller than that in the case of the first heat evacuation operation, and one second heat evacuation operation is short. You may make it stop and complete | finish in time.

  Further, when the second heat evacuation operation is performed by switching to the bypass circulation path, when the temperature of the high temperature sensor 51 provided in the heat collecting device 21 reaches a predetermined temperature close to the heat resistance temperature of the communication pipe, While the second heat evacuation operation is stopped or the second heat evacuation operation is continued, the heat medium circulation path is returned to the normal circulation path so that the heat medium circulates via the heat collector 21. It may be.

  In addition, in the embodiment, the bath water heater 12 of the type that burns and heats the burner 73 is used, but the heat source of the bath water heater is not limited to the burner.

  Further, it is only necessary that the hot water supplied from the hot water storage tank 14 can be used for hot water and pouring of the bath, and it is not essential to provide the bath water heater 12 at the rear stage of the hot water storage system 11. For example, the connection pipe 16 may be branched in the middle, one leading to a hot water tap and the other leading to the bathtub 3 via a pouring valve. In this case, the hot water storage system 11 can open and close the pouring valve. Control is sufficient. Further, the hot water storage system 11 may include a bathtub water circulation path and a pump for circulating the bathtub water.

  In the embodiment, the second heat evacuation operation is performed using the water-water heat exchanger 20. For example, the second heat exchange pipe is passed through the lower part of the hot water storage tank 14 to go to the bath. The second heat exchange pipe may be inserted in the middle of the pipe 31 or the bath return pipe 32. In addition, a valve that switches between passing or bypassing the second heat exchange pipe is provided, bypassing in a normal reheating operation, and bath water passing through the second heat exchange pipe in performing the second heat escape operation And may be configured to circulate.

  In the embodiment, the bath water heater 12 is of a single can and two water channel type, but it may be a water heater that performs separate bathing and hot water supply using separate heat exchangers.

DESCRIPTION OF SYMBOLS 3 ... Bathtub 10 ... Hot water supply system 11 ... Hot water storage system 12 ... Bath water heater 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 ... 1st valve 17b ... 2nd Valve 18 ... Heat exchange pipe 19 ... Systurn 19a ... Water level sensor 19b ... Opening to atmosphere 19c ... Tube 20a ... Inner pipe line 20b ... Outer pipe line 21 ... Heat collector 22 ... Heat medium circulation path 22a ... First heat Medium piping 22b ... second heating medium piping 22c ... third heating medium piping 22d ... fourth heating medium piping 24 ... circulation pump 25 ... switching valve 25a ... first connection port 25b ... second connection port 25c ... third connection port 26 ... connecting pipes 27a, 27b ... connecting pipe connection part 31 ... bath outlet pipe 32 ... bath return pipe 41 ... first temperature sensor 42 ... second temperature sensor 43 ... third temperature sensor 44 ... Fourth temperature sensor 46 ... Tank hot water temperature sensor 47 ... Water supply temperature sensor 48 ... Water volume 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 base 71 ... Inlet pipe 72 ... Heat exchanger 72a ... Hot water supply water pipe 72b ... Additional cooking 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 volume servo 80 ... Hot water temperature 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 ... Bath temperature sensor 88 ... Bath return temperature sensor 89 ... Control panel (common remote control)
89a ... Clock unit 91 ... Hot water pipe outlet temperature sensor

Claims (9)

A hot water storage tank with a water supply pipe connected to the inlet, and a pipe connected to the bathtub through a pouring valve controlled to open and close;
A heating device for raising the temperature of the water in the hot water storage tank with heat obtained by a heat collecting device for collecting solar heat;
A control unit for controlling a heat collecting operation for collecting heat obtained by the heat collecting device;
Have
The heat collecting operation includes a heat collecting operation for raising the temperature of the water in the hot water storage tank by the heating device by the heat obtained by the heat collecting device, and the temperature of the hot water in the hot water storage tank is increased, thereby reducing the heat recovery efficiency. A heat evacuation operation to move the heat in the hot water storage tank to the hot water in the bathtub when
As one of the heat evacuation operations, the controller opens the pouring valve so that the hot water in the hot water storage tank is transferred to the bathtub on the condition that the temperature of the hot water in the hot water storage tank is at least a predetermined temperature. A solar heat utilization system characterized by performing a first control to be poured into the water. The inlet is provided in the lower part of the hot water storage tank,
The outlet is provided in the upper part of the hot water storage tank,
The heating device heats hot water in the lower part of the hot water storage tank,
The solar control system according to claim 1, wherein the control unit determines whether or not a temperature of hot water in a lower portion of the hot water storage tank is equal to or higher than the predetermined temperature. When the temperature of the hot water in the hot water storage tank drops to a second temperature lower than the predetermined temperature, the control unit stops the first control and intermittently performs hot water pouring by the first control. The solar-heat utilization system of Claim 1 or 2 characterized by the above-mentioned. One end is connected to the bathtub water intake opening opened in the bathtub, the other end is connected to the bathtub water return opening opened in the bathtub, and provided in the middle of the bathtub water circulation path through which the bathtub water can be circulated by a pump And a second heating device that heats the hot water in the bathtub water circulation path using the hot water in the hot water storage tank as a heat source,
The controller, as one of the heat evacuation operations, is provided that at least the temperature of the hot water in the hot water storage tank is equal to or higher than a predetermined temperature, and the water level in the bathtub reaches the bathtub water intake port. And the second water heating device acts to heat the hot water in the hot water storage tank and heat the hot water in the hot water storage tank to perform the second control. The solar heat utilization system according to any one of claims 1 to 3. The control unit performs the first control on condition that the water level in the bathtub is lower than a set water level, and performs the second control when the water level in the bathtub reaches the set water level. The solar heat utilization system according to claim 4. The heating device includes the heat collecting device, a heat exchanger for heating hot water in the hot water storage tank, and a heat medium fluid circulation path formed between the heat collecting device and the heat exchanger. A circulation pump for circulating a heat medium fluid between the heat collecting device and the heat exchanger through the circulation path,
In the second heating device, a first heat exchange pipe is connected in the middle of the circulation path, and a second heat exchange pipe that exchanges heat with the first heat exchange pipe is connected in the middle of the bathtub water circulation path. Have a heat exchanger,
A switching valve for switching the circulation path to a normal path that passes through the heat collector and a bypass path that bypasses the heat collector;
In the second control, the control unit sets the circulation path to the bypass path with the switching valve to operate the circulation pump at full speed, and the temperature of the hot water in the hot water storage tank is lower than the predetermined temperature. The solar heat utilization system according to claim 4 or 5, wherein the second control is stopped when the temperature falls to two temperatures. The outlet of the hot water storage tank is connected to a pipe leading to a water supply port of a bath water heater having the pouring valve and having a function of pouring water into the bathtub.
The solar control according to any one of claims 1 to 6, wherein the control unit instructs the bath water heater to perform a pouring operation without heating in the first control. system. The bath water heater has a function of circulating hot water in the bathtub by circulating the hot water in the bathtub to the bathtub water circulation path with the pump,
The said control part instruct | indicates to operate the said pump without heating with respect to the said bath water heater in said 2nd control. The citation of any one of Claims 4 thru | or 6 characterized by the above-mentioned. The solar heat utilization system according to 7.   The solar heat utilization system according to claim 7 or 8, comprising the bath water heater.

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