JP4523809B2 - Water heater - Google Patents

Description

  The present invention relates to an apparatus for storing hot water heated by power generation generated by power generation or solar heat in a hot water storage tank and supplying hot water to a hot water use location when necessary. Specifically, the present invention relates to a hot water supply apparatus that displays the amount of mixed hot water that can be used at a hot water use location.

  An apparatus has been developed in which hot water heated by generated heat or solar heat is stored in a hot water storage tank, and hot water is supplied to a hot water use location when necessary.

This type of hot water supply device includes a hot water storage tank for storing hot water, and a mixing unit that mixes the hot water from the hot water storage tank and tap water and sends mixed hot water adjusted to a hot water supply set temperature. The hot water set temperature can be set by the user, and the temperature set by the user is stored in the hot water set temperature storage means.
When the temperature of the hot water stored in the hot water tank is higher than the hot water set temperature stored in the hot water set temperature storage means, the hot water is mixed with low-temperature tap water by the mixing unit. The mixing unit sends out the mixed hot water adjusted to the hot water supply set temperature.
In order to maintain hot water supply even when the temperature of the hot water stored in the hot water storage tank is lower than the hot water supply set temperature, an auxiliary heat source device is often incorporated into the hot water supply device.
Usually, they are arranged in the order of hot water storage tank, mixing unit, and auxiliary heat source machine. When the temperature of the hot water stored in the hot water storage tank is higher than the hot water supply set temperature, mixed hot water adjusted to the hot water supply set temperature is sent out by mixing with tap water in the mixing unit. In this case, the mixed hot water adjusted to the hot water supply set temperature passes through the auxiliary heat source machine, and the mixed hot water adjusted to the hot water supply set temperature is supplied to the hot water use location. When the temperature of the hot water stored in the hot water storage tank is lower than the hot water supply set temperature, the hot water sent out from the mixing unit (which may be cold water) is heated by the auxiliary heat source machine and heated to the hot water supply set temperature by the auxiliary heat source machine. Supply the warm water to the hot water use location.

This type of hot water supply apparatus is often installed by a user in anticipation of an energy saving effect. Patent Document 1 discloses a technique for displaying the extent to which hot water that has been stored contributes to hot water supply. In this technique, a value (reach rate) obtained by dividing the temperature difference between the hot water temperature and the tap water temperature stored in the hot water tank by the temperature difference between the hot water set temperature and the tap water temperature is calculated and displayed. When the amount of hot water to be mixed in the mixing unit is low due to the hot water temperature of the hot water being stored, a large reaching rate is displayed, and when the amount of hot water to be mixed in the mixing unit is increased due to a decrease in the hot water temperature of the hot water, a small reaching rate is displayed. The
Japanese Patent Laid-Open No. 2003-4302

The technique of Patent Document 1 is excellent in that it can grasp how much the hot water stored in the hot water tank contributes to the hot water supply of the mixed hot water.
However, users want to know how much hot water can be used or how much time it can be used by using hot water stored in the hot water tank more directly. Also have. Even if the amount of heat stored in the hot water storage tank is the same, a large amount of mixed hot water can be used if the hot water supply set temperature is lowered, and a large amount of mixed hot water can be used if the tap water temperature is high. There is a demand for users to know the amount of heat stored in units of time such as the amount of water or the continuous usable time, rather than the amount of abstract dimension of heat. If the heat storage amount can be known in units of water amount or time, it becomes easy to study a method for effectively using the mixed hot water within the range of the heat storage amount, and it becomes easy to plan a method for using the mixed hot water useful for energy saving.

  In this invention, the magnitude of the heat storage amount stored in the hot water storage tank is displayed as the amount of mixed hot water that can be used when the user continues the hot water supply currently used. The amount of mixed hot water that can be used varies depending on the adjustment of the hot water supply set temperature. If the hot water supply set temperature is lowered, the available mixed hot water amount increases, and if the hot water supply set temperature is raised, the available mixed hot water amount decreases. The user can know the amount of mixed hot water that can be used within the range of the heat storage amount, and can easily plan a method of using the mixed hot water that is useful for energy saving.

(Hand stage for Solving the Problems)
The hot water supply apparatus of the present invention includes a hot water storage tank for storing hot water, a heat storage amount calculating means for calculating the heat storage amount stored in the hot water storage tank at predetermined time intervals, a hot water tap for supplying hot water to the shower and bath tub, Hot water set temperature storage means for storing a set temperature of hot water to be supplied to a hot water use location including at least one other hot water tap, and hot water from a hot water tank and tap water are mixed to a hot water set temperature storage means Mixing unit for sending mixed hot water adjusted to stored hot water supply set temperature, tap water temperature detection means for detecting tap water temperature, and heat storage amount and hot water supply set temperature calculated by heat storage amount calculation means at predetermined time intervals Based on the hot water supply set temperature stored in the storage means and the tap water temperature detected by the tap water temperature detecting means, the amount of mixed hot water available at the hot water use location is calculated at predetermined time intervals. And stage, a mixed hot water flow rate and the hot water flow rate storage unit for storing the flow rate of the mixed hot water when the hot water supply to the other water tap, available mixed hot water amount calculation means predetermined time interval when the hot water in the shower It is possible to supply hot water to the shower with the mixed hot water adjusted to the hot water set temperature from the calculated available hot water amount, the mixed hot water flow rate stored in the hot water flow rate storage means, and the mixed hot water flow rate of other hot water taps. Available time calculating means for calculating hot water and other hot water supply time available at predetermined time intervals, available mixed hot water amount calculated by the available mixed hot water amount calculating means at predetermined time intervals, and available time with calculating means is displayed together available time shower available time and other water tap of the calculated at predetermined time intervals, the available mixing amount of hot water does not exceed the bath tub volume Displays the bath water level in the bath tub, and when the bath tub volume is exceeded, the shower availability time and other hot water taps can be used by subtracting the bath tub volume. Display means for displaying time together .
The heat storage amount calculation means can be configured by various methods. For example, if hot water temperature measurement means are prepared at a plurality of locations in the depth direction of the hot water storage tank, hot water storage at a depth corresponding to each hot water temperature measurement means. The heat storage amount of the entire hot water storage tank can be calculated by summing the heat storage amount obtained by multiplying the volume by the hot water temperature in the depth direction. Alternatively, the remaining heat storage amount may be calculated from the heat storage amount calculated at a certain point in time and the hot water temperature and the hot water amount sent out from the hot water tank thereafter.

(The action and effect)
In the hot water storage tank, hot water heated by generated heat, solar heat, or the like is stored, and the amount of heat of the hot water is stored.
The amount of heat stored in the hot water tank can be calculated by various methods. In the simplest example, hot water having an average temperature of 70 ° C. is stored in a hot water tank having a volume of 30 liters, and if the tap water temperature is 10 ° C., (70−10) × 30 = 1800 (liters) X ° C) can be calculated as the amount of heat stored by being heated from the tap water temperature. If the amount of stored heat is calculated, the amount of mixed hot water capable of supplying hot water can be calculated from the tap water temperature and the hot water supply set temperature.
For example, if the tap water temperature is 10 ° C. and the hot water supply set temperature is 40 ° C., the mixing unit can mix hot water from the hot water tank with the same amount of tap water, and 60 liters of mixed hot water It turns out that hot water can be supplied. That is, when the difference between the tap water temperature and the hot water supply set temperature is 30 ° C., it is found from the heat storage amount that 1800 ÷ (40−10) = 60 liters of hot water can be supplied. If the tap water temperature is 10 ° C and the hot water supply set temperature is 50 ° C, the mixing unit can mix hot water from the hot water storage tank with half of the tap water, and supply 45 liters of hot water. It turns out that. That is, when the difference between the tap water temperature and the hot water supply set temperature is 40 ° C., it is found from the heat storage amount that 1800 ÷ (50−10) = 45 liters can be supplied. If the tap water temperature is 10 ° C and the hot water supply set temperature is 30 ° C, the mixing unit can mix hot water from the hot water tank with double the amount of tap water, and can supply hot water of 90 liters of hot water. It turns out that. That is, when the difference between the tap water temperature and the hot water supply set temperature is 20 ° C., it is found from the above heat storage amount that 1800 ÷ (30−10) = 90 liters can be supplied.
In the hot water supply apparatus of the present invention, the calculated mixed hot water amount capable of hot water supply is displayed. In the case of the above example, if the hot water supply set temperature is 30 ° C., it is displayed that 90 liters of hot water can be supplied, and if the hot water supply set temperature is 40 ° C., it is displayed that 60 liters of hot water can be supplied. If it is 50 degreeC, it will be displayed that 45 liters hot water supply is possible. If the hot water supply set temperature is reset, the available amount of mixed hot water is recalculated, and the newly calculated available amount is displayed.
According to the hot water supply apparatus of the present invention, it is possible to directly know the amount of mixed hot water that can be used when hot water supply is continued at the hot water supply set temperature currently used. The user can devise a method for finishing work that requires hot water supply within the already stored range.
Further, in the hot water supply apparatus of the present invention, for example, when the flow rate of the mixed hot water to be supplied in the shower is stored as 10 (liters / minute), if the available mixed hot water amount is 60 (liters), 60 ÷ 10 = 6 (minutes) is calculated as the available time for hot water supply in the shower. If the flow rate of the mixed hot water to be supplied with the hot water tap is stored as 6 (liters / minute), if the available mixed hot water amount is 90 (liters), 90 ÷ 6 = 15 (minutes) is hot water supplied with the hot water tap. Calculated as possible available time. The display shows the available time for the shower and the available time for the hot water tap. For this reason, it becomes easy for the user to take energy saving measures such as keeping the shower within 6 minutes or using the hot water tap within 15 minutes.
For example, when the bath water level is 150 (liters) and the available mixed hot water amount is 35.0 (liters), 35.0 ÷ 150 × 10 = 2.3 is the bath water level. If the calculated mixed hot water amount is 150 (liters), the water level of the bath is calculated as the highest water level (full water level) 10. When the amount of hot water that can be used exceeds 150 (liters), based on the value obtained by subtracting 150 (liters) from the amount of hot water that can be used, the time that hot water can be supplied to the shower and the time that hot water can be supplied to other hot water taps Is calculated, and the available time of the shower and the available time of other hot water taps are displayed together. From these displays, the user can use the hot water without impairing the energy saving effect.
Moreover, the heat storage amount stored in the hot water storage tank increases, for example, when the recovered heat amount is added, and decreases when the mixed hot water is used. According to the hot water supply apparatus of the present invention, the heat storage amount calculation means calculates the heat storage amount at a predetermined time interval, for example, in seconds or minutes, and the available mixed hot water amount calculation means can use the available mixed hot water based on the heat storage amount. If the amount is calculated, the display means can display the amount of mixed hot water that can be used that changes with the amount of heat storage that changes every moment. Further, if the heat storage amount calculation means calculates the heat storage amount at a predetermined time interval, and the available time calculation means calculates the available time based on the heat storage amount, the display means displays the heat storage amount that changes every moment. The available time of the shower and the available time of the hot water tap that change with the display can be displayed together.

The best mode for carrying out the invention is listed below.
(Embodiment 1) When the amount of available mixed hot water exceeds the bathtub volume of the bath, the display unit displays the available time of other hot water supply usage locations with a value obtained by subtracting the bathtub volume.

A hot water supply apparatus 10 according to an embodiment of the present invention and a power generation unit 110 that supplies heat to the hot water supply apparatus 10 will be described with reference to the drawings.
First, the power generation unit 110 will be described. As shown in FIG. 1, the power generation unit 110 includes a reformer 112, a fuel cell 114, heat exchangers 116 and 118, a heat medium radiator 120, a heat medium three-way valve 122, a path for connecting them, and the like. I have.
The reformer 112 includes a burner 131. When the burner 131 is operated to generate heat, the reformer 112 generates hydrogen gas from hydrocarbon-based gas. One end of a combustion gas path 126 is connected to the reformer 112. The other end of the combustion gas path 126 is open to the outside. The combustion gas path 126 passes through the heat exchanger 116. The combustion gas generated by the burner 131 flows through the combustion gas path 126 and is discharged outside after the temperature is lowered by the heat exchanger 116. The circulation path 128 also passes through the heat exchanger 116. The circulation path 128 includes a circulation return path 128 a and a circulation outward path 128 b and is connected to the hot water supply apparatus 10. The connection state between the circulation path 128 and the hot water supply device 10 will be described in detail later. The circulation path 128 circulates hot water. When the hot water flowing through the circulation path 128 passes through the heat exchanger 116, it is heated by the combustion gas flowing through the combustion gas path 126, and the temperature rises.

The fuel cell 114 has a plurality of cells. The fuel cell 114 and the reformer 112 are connected by a hydrogen gas supply path 121. The hydrogen gas generated by the reformer 112 flows through the hydrogen gas supply path 121 and is supplied to the fuel cell 114. The fuel cell 114 generates power by reacting the hydrogen gas supplied from the reformer 112 with oxygen in the air. The fuel cell 114 generates heat when it generates power. The generated electric power is supplied to the outside (for example, a house).
The heat medium circulation path 124 forms a path that returns to the fuel cell 114 via the fuel cell 114, the heat exchanger 118, the reserve tank 125, the heat medium pump 127, and the heat medium three-way valve 122. As the heat medium flowing through the heat medium circulation path 124, for example, pure water can be used. A heat medium temperature sensor 117 is attached to the heat medium circulation path 124 on the downstream side of the fuel cell 114. The heat medium temperature sensor 117 detects the temperature of the heat medium flowing through the heat medium circulation path 124. The detection signal of the heat medium temperature sensor 117 is output to a controller 21 (described later) provided in the hot water supply apparatus 10.
The heat medium three-way valve 122 includes one inlet 122a and two outlets 122b and 122c. The heat medium three-way valve 122 communicates the inlet 122a and the outlet 122b or communicates the inlet 122a and the outlet 122c by switching the internal flow path.
A cooling path 129 that connects the outlet 122b of the heat medium three-way valve 122 and the heat medium circulation path 124 on the downstream side of the outlet 122c is provided. In the middle of the cooling path 129, a heat medium radiator 120 is mounted. A heat medium cooling fan 119 is provided adjacent to the heat medium radiator 120. When the heat medium cooling fan 119 rotates, air is blown to the heat medium radiator 120 to cool the heat medium flowing through the cooling path 129.
The reformer 112, the fuel cell 114, the burner 131, the heat medium three-way valve 122, the heat medium pump 127, and the heat medium cooling fan 119 are controlled by the controller 21.

When the fuel cell 114 is activated, the inlet 122a and the outlet 122c of the heat medium three-way valve 122 are communicated and the heat medium pump 127 is operated. When the heat medium pump 127 is operated, the heat medium circulates through the heat medium circulation path 124. When the heat medium circulates through the heat medium circulation path 124, the generated heat is recovered from the fuel cell 114. The generated heat recovered by the heat medium is transported together with the heat medium to the heat exchanger 118 and heats the hot water flowing through the circulation path 128.
If the heat medium temperature detected by the heat medium temperature sensor 117 becomes too high, the inlet 122a and the outlet 122b of the heat medium three-way valve 122 are communicated. At the same time, the heat medium cooling fan 119 rotates. When the inlet 122 a and the outlet 122 b of the heat medium three-way valve 122 communicate with each other, the heat medium flows into the cooling path 129 and passes through the heat medium radiator 120. The heat medium is cooled by passing through the heat medium radiator 120. Since the heat medium cooling fan 119 blows air to the heat medium radiator 120, the heat medium radiator 120 radiates heat with high efficiency. When the temperature of the heat medium decreases, the inlet 122a and the outlet 122c of the heat medium three-way valve 122 are communicated again. In this way, the switching of the internal flow path of the heat medium three-way valve 122 is repeated, and the temperature of the heat medium is maintained within a predetermined range.

The hot water supply device 10 will be described.
As shown in FIG. 1, the hot water supply apparatus 10 includes a hot water tank 20, a mixing unit 24, an auxiliary heat source machine 22, a plurality of paths that communicate these, a controller 21, and the like.
A water supply path 26 for supplying tap water to the hot water tank 20 is connected to the bottom of the hot water tank 20. In the vicinity of the inlet 26 a of the water supply path 26, a pressure reducing valve 28 is attached. The water supply path 26 on the downstream side of the pressure reducing valve 28 and the water supply inlet 24 a of the mixing unit 24 are connected by a mixing unit water supply path 30. The pressure reducing valve 28 adjusts the water supply pressure to the hot water storage tank 20 and the mixing unit 24 to a predetermined pressure regulation value. When the hot water in the hot water storage tank 20 decreases or the water supply inlet 24a of the mixing unit 24 opens, the downstream pressure of the pressure reducing valve 28 decreases. The pressure reducing valve 28 opens when the downstream pressure decreases, and tries to maintain the pressure at a regulated pressure value. For this reason, when the hot water in the hot water tank 20 decreases, tap water is supplied to the hot water tank 20. When the water supply inlet 24 a of the mixing unit 24 is opened, tap water is supplied to the mixing unit 24.
An outlet 20a is provided at the upper part of the hot water tank 20, and a relief valve 31 is mounted thereon. The valve opening pressure of the relief valve 31 is set slightly higher than the pressure regulation value of the pressure reducing valve 28. When the pressure regulation of the pressure reducing valve 28 becomes impossible, the relief valve 31 is opened to prevent the pressure in the hot water tank 20 from exceeding the pressure resistance. One end 32 a of a pressure release path 32 is connected to the relief valve 31. The other end 32 b of the pressure release path 32 is open to the outside of the hot water tank 20.
The bottom of the hot water tank 20 and the vicinity of the other end 32 b of the pressure release path 32 are connected by a drainage path 33. A drain valve 34 that can be manually opened and closed is mounted in the middle of the drain passage 33. When the drain valve 34 is opened, the water in the hot water tank 20 is drained to the outside through the drain path 33 and the pressure release path 32.

The controller 21 includes a CPU, a ROM, a RAM, and the like, and the hot water supply device 10 is controlled by the CPU processing a control program stored in the ROM. The ROM stores data necessary for various calculations such as the flow rate of a shower and other hot water taps. The RAM temporarily stores various signals input to the controller 21 and various data generated in the course of execution of processing by the CPU.
A remote controller 23 is connected to the controller 21. As shown in FIG. 4 and the like, the remote controller 23 is provided with switches and buttons for operating the hot water supply device 10, a liquid crystal display 23a, and the like. Information displayed on the display 23a will be described in detail later.

As shown in FIG. 1, the hot water storage tank 20 is connected to the power generation unit 110 by a circulation path 128 (a circulation return path 128a and a circulation outward path 128b). The circulation return path 128 a is connected to the upper part of the hot water tank 20. The circulation outward path 128 b is connected to the lower part of the hot water tank 20. A circulation pump 40 is mounted in the middle of the circulation outward path 128b.
When the circulation pump 40 is activated, hot water is sucked out from the bottom of the hot water tank 20. The hot water sucked out from the hot water storage tank 20 flows through the circulation path 128b and then passes through the heat exchangers 116 and 118 of the power generation unit 110. The hot water that has passed through the heat exchangers 116 and 118 is heated and the temperature rises. The hot water whose temperature has risen returns to the upper part of the hot water tank 20 through the circulation return path 128a. In this way, the hot water sucked out from the bottom of the hot water tank 20 is heated by the heat exchangers 116 and 118 of the power generation unit 110 to be further heated, and circulation is performed to return to the upper part of the hot water tank 20. Hot water is stored in the hot water tank 20. When hot water is supplied from the power generation unit 110 to the hot water tank 20 in a state where the temperature in the hot water tank 20 is low (the hot water tank 20 is not fully stored), the supply is supplied to the upper part of the hot water tank 20. Since it is performed, a hot water layer (temperature stratification) is formed on top of the hot water stored in the hot water tank 20. The temperature of the hot water along the depth direction of the hot water storage tank 20 rapidly decreases as it becomes deeper than the temperature stratification. When the supply of hot hot water to the hot water tank 20 is continued, the thickness (depth) of the temperature stratification gradually increases, and when the hot water tank 20 is fully stored, hot water in the entire hot water tank 20 is heated. Will be accumulated. By forming the temperature stratification, high-temperature hot water is sent out from the outlet portion 20a provided at the uppermost portion of the hot water storage tank 20 even if the hot water storage tank 20 is not fully stored.
A forward thermistor 44 that detects the temperature of hot water sucked from the hot water storage tank 20 is mounted in the middle of the circulation outward path 128b. A return thermistor 45 that detects the temperature of the hot water returned to the hot water tank 20 is mounted in the middle of the circulation return path 128a. Detection signals from the forward thermistor 44 and the return thermistor 45 are output to the controller 21.

The hot water tank 20 is provided with an upper thermistor 35, an intermediate thermistor 39, and a lower thermistor 36. The upper thermistor 35 detects the upper temperature of the hot water tank 20. The intermediate thermistor 39 detects the intermediate temperature of the hot water tank 20. The lower thermistor 36 detects the lower temperature of the hot water tank 20. Detection signals from the upper thermistor 35, the intermediate thermistor 39, and the lower thermistor 36 are output to the controller 21.
The mixing unit 24 includes a hot water inlet 24c, a mixed hot water outlet 24b, a first water amount sensor 67, a hot water inlet thermistor 50, a water supply thermistor 48, a mixed hot water outlet thermistor 54, a high-cut thermistor 55, and the water supply inlet 24a already described. Yes. The outlet 20 a of the hot water tank 20 and the hot water inlet 24 c of the mixing unit 24 are connected by a hot water path 42. The first water amount sensor 67 detects the flow rate of the warm water flowing out from the mixed warm water outlet 24b. The hot water inlet thermistor 50 detects the temperature of the hot water flowing into the hot water inlet 24c. The water supply thermistor 48 detects the temperature of the tap water flowing into the water supply inlet 24a. The mixed hot water outlet thermistor 54 and the high cut thermistor 55 detect the temperature of the hot water flowing out from the mixed hot water outlet 24b. Detection signals of the first water amount sensor 67, the hot water inlet thermistor 50, the water supply thermistor 48, the mixed hot water outlet thermistor 54, and the high cut thermistor 55 are output to the controller 21.

The controller 21 uses the detection signal of the mixed hot water outlet thermistor 54 to change the opening on the hot water inlet 24c side and the opening on the water supply inlet 24a side. When the opening degree on the hot water inlet 24c side and the opening degree on the water supply inlet 24a side are changed, the mixing ratio between the hot water from the hot water storage tank 20 and tap water (cold water) is adjusted. When the mixing ratio between the hot water from the hot water tank 20 and the tap water is adjusted, the temperature of the hot water flowing out from the mixed hot water outlet 24b is maintained at a predetermined value. When the high-cut thermistor 55 detects that the temperature of the hot water flowing out from the mixed hot water outlet 24b has greatly exceeded the predetermined value (that is, when there is a high possibility that the mixing unit 24 has failed), the controller 21 detects the hot water inlet 24c. Close. When the hot water inlet 24c is closed, it is possible to prevent the hot water whose temperature is too high from being supplied to the auxiliary heat source unit 22.
The mixed hot water outlet 24 b of the mixing unit 24 and the burner heat exchanger 52 (described later) of the auxiliary heat source unit 22 are connected by a mixed hot water path 51. A second water amount sensor 47 is attached to the mixed hot water path 51. A detection signal from the second flow sensor 47 is output to the controller 21.

The auxiliary heat source unit 22 includes burner heat exchangers 52 and 60, a hot water supply burner 56, a heating burner 57, a reheating heat exchanger 58, a replenishing water valve 59, a cistern 61, and the like.
The mixed warm water flows from the mixing unit 24 into the burner heat exchanger 52 via the mixed warm water path 51. The hot water supply burner 56 heats the burner heat exchanger 52 by burning gas. The downstream side of the burner heat exchanger 52 and the hot water tap 64 are connected by a hot water tap path 63. The hot-water tap 64 is arranged in a bathroom, a washroom, a kitchen, etc. (in FIG. 1, these plural hot-water taps 64 are shown as one representative). A shower is connected to one of the hot water taps 64 arranged in the bathroom. A hot water supply thermistor 65 is attached to the hot-water tap path 63. The hot water thermistor 65 detects the temperature of the hot water flowing out of the burner heat exchanger 52. A detection signal from the hot water thermistor 65 is output to the controller 21. The controller 21 controls the operation of the hot water supply burner 56 based on the hot water temperature detected by the hot water thermistor 65. The case where the hot water supply burner 56 operates will be described later.

From the middle of the mixed hot water path 51 in the auxiliary heat source unit 22, a systern water inlet path 62 is branched. The open end of the cistern water inlet path 62 is inserted into the upper part of the cistern 61. A makeup water valve 59 is provided in the middle of the cistern water intake path 62. The makeup water valve 59 is controlled by the controller 21 and is driven by a built-in solenoid to open and close. When the replenishing water valve 59 is opened, hot water from the mixing unit 24 is supplied to the cistern 61.
A water level electrode 66 is mounted in the cis turn 61. The water level electrode 66 has a rod-shaped high level switch 66a and a low level switch 66b. The lower end of the high level switch 66 a is located at the high level water level of the cistern 61. The lower end of the low level switch 66 b is located at the low level water level of the cistern 61. The high level switch 66a and the low level switch 66b output a detection signal to the controller 21 when they are in contact with water. Based on the detection signal from the water level electrode 66, the controller 21 determines whether the water level of the cistern 61 exceeds the high level water level, is between the high level water level and the low level water level, or is lower than the low level water level. The controller 21 controls the opening and closing of the replenishing water valve 59 based on the water level detection signal from the water level electrode 66, and maintains the water level of the cistern 61 between the high level water level and the low level water level.

One end of a cistern water discharge path 68 is connected to the bottom of the cistern 61. A heating pump 69 is installed in the middle of the cistern water discharge path 68. The heating pump 69 is controlled by the controller 21. The other end of the cistern water discharge path 68 and the upstream end of the burner heat exchanger 60 are connected by a burner upstream path 71. A heating thermistor 72 that detects the temperature of hot water flowing through the burner upstream path 71 is mounted. The detection signal of the heating thermistor 72 is output to the controller 21. A low temperature water path 70 is also connected to the other end of the cistern water discharge path 68.
The heating burner 57 burns gas to heat the burner heat exchanger 60. The downstream of the burner heat exchanger 60 and the cistern 61 are connected by a high-temperature water path 73. A high temperature thermistor 74, a heating terminal thermal valve 75, and a heating terminal 76 are attached to the high temperature water path 73 in order from the upstream side.
The high temperature thermistor 74 detects the temperature of the hot water flowing through the high temperature water path 73. A detection signal from the high temperature thermistor 74 is output to the controller 21.

The heating terminal 76 includes a heat exchanger 76b, an operation switch 76a, and an electric fan (not shown). The heat exchanger 76 b performs heat exchange between the surrounding air and hot water flowing through the high temperature water path 73. The operation switch 76 a is connected to the heating terminal thermal valve 75 and the controller 21.
The heating terminal thermal valve 75 includes an expansion element and an on-off valve mechanically connected to the expansion element. When the operation switch 76a of the heating terminal 76 is turned on, power is supplied to the expansion element of the heating terminal thermal valve 75. The energized expansion element becomes hot and expands. The expanded expansion element drives the on-off valve, thereby opening the heating terminal thermal valve 75. Further, when the operation switch 76 a is turned on, the controller 21 operates the heating pump 69. As described above, when the operation switch 76 a is turned on, the heating terminal thermal valve 75 is opened, and the heating pump 69 is operated, hot water is sucked out from the cistern 61. The controller 21 controls the heating burner 57 based on the hot water temperature detected by the heating thermistor 72 and the high temperature thermistor 74, and maintains the temperature of the hot water flowing out of the burner heat exchanger 60 within a predetermined range. The electric fan of the heating terminal 76 rotates when the operation switch 76a is turned on, and blows air to the heat exchanger 76b. The air blown to the heat exchanger 76b is heated by exchanging heat with warm water via the heat exchanger 76b. The heated air is heated from the heating terminal 76 to heat the room. The temperature of the hot water that has passed through the heat exchanger 76b is reduced due to heat being taken away (by heat exchange) by the air. The hot water whose temperature has decreased flows through the high-temperature water path 73 and returns to the cistern 61.

The downstream side of the high temperature thermistor 74 in the high temperature water path 73 and the upstream side of the connection portion of the high temperature water path 73 with the cistern 61 are connected by a tracking path 77. The tracking path 77 passes through the tracking heat exchanger 58. On the upstream side of the tracking heat exchanger 58 in the tracking path 77, a tracking thermal valve 78 is mounted. The reheating heat valve 78 is controlled by the controller 21.
The bathtub 79 is provided with a suction port 79a and a supply port 79b. The suction port 79 a and the supply port 79 b are connected by a bath circulation path 80. The bath circulation path 80 passes through the reheating heat exchanger 58. As described above, the tracking path 77 also passes through the tracking heat exchanger 58. For this reason, in the reheating heat exchanger 58, heat exchange is performed between the hot water flowing in the bath circulation path 80 and the reheating path 77. A bath water level sensor 81, a bath circulation pump 82, and a bath water flow switch 84 are mounted on the upstream side of the reheating heat exchanger 58 in the bath circulation path 80. The bath circulation pump 82 is controlled by the controller 21. The bath water level sensor 81 and the bath water flow switch 84 output detection signals to the controller 21. The bath water level sensor 81 detects water pressure. The controller 21 estimates the water level of the hot water stretched on the bathtub 79 from the water pressure detected by the bath water level sensor 81. The detection signal of the bath water flow switch 84 is used to determine whether or not there is a water flow in the bath circulation path 80.
A bath inlet thermistor 97 is provided on the downstream side of the reheating heat exchanger 58 in the bath circulation path 80. The bath inlet thermistor 97 detects the temperature of hot water filled in the bathtub 79. On the upstream side of the bath water level sensor 81 in the bath circulation path 80, a bath outlet thermistor 85 that detects the temperature of the hot water sucked out from the bathtub 79 is mounted. Detection signals from the bath entrance thermistor 97 and the bath exit thermistor 85 are output to the controller 21.

  When the reheating heat valve 78 is opened while the heating burner 57 and the heating pump 69 are operating, hot water flows into the reheating path 77 and passes through the reheating heat exchanger 58. When the bath circulation pump 82 is activated, the hot water is sucked out from the suction port 79a of the bathtub 79, flows through the bath circulation path 80, and returns to the bathtub 79 from the supply port 79b again. The hot water flowing through the bath circulation path 80 is heated by the reheating heat exchanger 58 by the hot water flowing through the reheating path 77, whereby the hot water in the bathtub 79 is reclaimed.

A hot water filling path 25 that connects the middle of the hot-water tap path 63 and the downstream side of the bath circulation pump 82 of the bath circulation path 80 is provided. A solenoid drive type pouring valve 27 and a hot water filling amount sensor 83 are attached to the hot water filling passage 25. The pouring valve 27 is controlled by the controller 21 and opens and closes the hot water filling path 25. The hot water filling amount sensor 83 detects the amount of water supplied to the bathtub 79 through the hot water filling passage 25. The detection value of the hot water filling amount sensor 83 is output to the controller 21 and is used to estimate how much hot water filling is applied to the bathtub 79.
When hot water is filled in the bathtub 79, the pouring valve 27 is opened and the replenishing water valve 59 is closed. When the hot water supply valve 27 is opened and the replenishment water valve 59 is closed, hot water from the mixing valve 24 flows into the bath circulation path 80 from the hot water tap path 63 through the hot water filling path 25. When the temperature of the hot water from the mixing valve 24 is low, the hot water supply burner 56 operates. The hot water that has flowed into the bath circulation path 80 is supplied to the bathtub 79 from the suction port 79a and the supply port 79b, and fills the bathtub 79. At this time, the bath circulation pump 82 is not driven, and the hot water filling to the bathtub 79 is performed by the water pressure applied to the hot water filling passage 25.

The three-way valve 86 includes an A port 86a, a B port 86b, and a C port 86c. The three-way valve 86 is controlled by the controller 21 to switch between communication between the A port 86a and the C port 86c or communication between the B port 86b and the C port 86c.
The cistern water discharge path 68 and the C port 86 c of the three-way valve 86 are connected by a low-temperature water path 70. A floor heating thermistor 94 is mounted upstream of the low-temperature water path 70. The floor heating thermistor 94 detects the temperature of the hot water flowing through the low temperature water path 70. A detection signal of the floor heating thermistor 94 is output to the controller 21. The low-temperature water path 70 is branched into two low-temperature water branch paths 70a and 70b. The low-temperature water branch paths 70 a and 70 b pass through the floor heater 91. On the upstream side of the floor heater 91 in the low-temperature water branch paths 70a and 70b, floor heating thermal valves 95 and 96 are provided, respectively. The floor heating thermal valves 95 and 96 are controlled by the controller 21. The low-temperature water branch paths 70 a and 70 b merge on the downstream side of the floor heater 91 to become the low-temperature water path 70 again.
When performing floor heating, the remote controller 23 is operated. Then, the floor heating thermal valves 95 and 96 are opened, the hot water is guided to the floor heater 91 through the low-temperature water branch paths 70a and 70b, and the floor is warmed. The floor can also be partially warmed by operating the remote controller 23 and selecting which of the floor heating thermal valves 95, 96 to open.
The B port 86 b of the three-way valve 86 and the downstream side of the heating terminal 76 in the high temperature water path 73 are connected by a low temperature water return path 87. A low temperature return thermistor 89 is attached to the low temperature water return path 87. The low temperature water return thermistor 89 detects the temperature of the hot water flowing through the low temperature water return path 87. The detection signal of the low temperature water return thermistor 89 is output to the controller 21.
A hot water tank path 88 is provided to connect the A port 86a of the three-way valve 86 and the middle of the low-temperature water return path 87. In the hot water tank path 88, a heat exchange coil portion 88a passing through the upper part of the hot water tank 20 is formed.

  The controller 21 compares the temperatures detected by the floor heating thermistor 94 and the upper thermistor 35 and switches the three-way valve 86 according to the result. Specifically, when the temperature detected by the upper thermistor 35 is lower than the temperature detected by the floor heating thermistor 94, the B port 86b and the C port 86c of the three-way valve 86 are switched to communicate with each other. When the B port 86 b and the C port 86 c communicate with each other, the hot water from the low temperature water path 70 bypasses the hot water tank path 88, flows through the low temperature water return path 87 and the high temperature water path 73, and returns to the cistern 61. The hot water that has returned to the cistern 61 is sucked into the cistern water discharge path 68 again. When the temperature detected by the upper thermistor 35 is higher than the temperature detected by the floor heating thermistor 94, the A port 86a and the C port 86c of the three-way valve 86 are communicated. When the A port 86 a and the C port 86 c communicate with each other, the hot water from the low temperature water path 70 flows through the hot water tank path 88. The hot water flowing through the hot water tank path 88 is heated by the hot water stored in the upper part of the hot water tank 20 by the heat exchange coil section 88a, and the temperature rises. The hot water whose temperature has risen flows through the low-temperature water return path 87 and the high-temperature water path 73 and is returned to the cistern 61. That is, hot water is guided to the hot water tank path 88 only when the hot water stored in the upper part of the hot water tank 20 can heat the heat exchange coil portion 88a of the hot water tank path 88.

  In the hot water supply apparatus 10, when the hot water temperature requested by the user is set with the remote controller 23, the display 23a displays how much mixed hot water is available from the hot water storage tank 20 at the set temperature. Is done. Hereinafter, a configuration for realizing this display will be described.

The graph of FIG. 2 shows the amount of hot water demand generated for the hot water supply device 10 for a certain day, and the amount of heat stored in the hot water storage tank 20 of the hot water supply device 10 ( The amount of heat stored from the tap water temperature is shown. The horizontal axis of the graph is time, and the vertical axis is the accumulated hot water demand (kJ) and the heat storage amount (kJ). The accumulated hot water demand is indicated by a solid line. The length of the bottom of the shaded part surrounded by the solid line corresponds to the length of time that the hot water demand has continued. The amount of stored heat is indicated by a dotted line. c1-c6 have shown the time when the user confirmed the display of the indicator 23a on this day, and the time of the time slot | zone when the hot water demand has generate | occur | produced.
When the hot water demand is generated and the hot water in the hot water tank 20 is consumed, and the accumulated hot water demand exceeds the increase in the heat storage quantity, the heat storage quantity in the hot water tank 20 decreases. For example, in FIG. 2, the heat storage amount reaches a peak at the time point c4. At this time, although the hot water demand 152 is generated and the heat storage amount is reduced, the accumulated amount of the hot water demand 152 is small, so that the heat storage amount of the hot water tank 20 remains higher than the hot water demand 152. Further, at the time point c5, the hot water demand 154 is generated and the heat storage amount is reduced, and further, at the time point c6, the hot water demand 155 is newly generated and the heat storage amount is continuously reduced.
FIG. 3 is a correspondence table in which the graph of FIG. 2 is represented by specific times and numerical values. Here, only the time zone when the hot water demand occurs is extracted and shown. The accumulated hot water demand (kJ) for each time zone, the recovered heat amount (kJ) recovered from the generated heat in that time zone and stored in the hot water tank 20, and the heat storage amount (kJ) are shown. For example, in the time zone (5:52 (time of c1) to 5:58) when the first hot water demand occurs, the accumulated hot water demand during that period is 3117 (kJ) and the recovered heat amount is 184 (kJ). It is shown that the heat storage amount was 2933 (kJ) at 5:52 but decreased to 0 (kJ) at 5:58.

In the present embodiment, the hot water demand is generated at the hot water use locations of baths, showers, and other hot water taps (hereinafter simply referred to as “hot water taps”). The amount of hot water demand at each hot water use location is calculated as follows.
Hot water demand in bath = bath volume x (set temperature-feed water temperature) x 4.19;
Hot water demand in the shower = shower water supply per unit time x usage time x (set temperature-water supply temperature) x 4.19;
Hot water demand at hot water tap = hot water supply amount per unit time x usage time x (set temperature-water temperature) x 4.19;
“4.19” in the above formula is the specific heat of water (kJ / (liter · K)).
In this embodiment, the “tub volume” is 150 (liters), the “shower water supply amount per unit time” is 10 (liters / minute), and the “hot water supply amount per unit time” is 6 (liters / minute). These values are stored in advance.

In addition, the amount of heat storage is determined by the detected values of the upper thermistor 35, the intermediate thermistor 39, the lower thermistor 36, and the water supply thermistor 48 (hereinafter referred to as “water supply temperature”) and the volume of the upper portion of the hot water tank 20 (hereinafter referred to as “hot water tank upper portion” Volume ”), the volume of the intermediate part of the hot water tank 20 (hereinafter referred to as“ the hot water tank intermediate part volume ”), and the volume of the lower part of the hot water tank 20 (hereinafter referred to as“ the hot water tank lower volume ”). Can be obtained from the following equation.
Heat storage amount = {(Upper thermistor detection value−Water supply temperature) × Hot water storage tank upper volume
+ (Intermediate thermistor detection value-feed water temperature) x hot water tank intermediate volume
+ (Lower thermistor detection value-feed water temperature) x hot water tank lower volume} x 4.19;
This heat storage amount is calculated and memorized every moment.

Hereinafter, the relationship between the accumulated hot water demand, the recovered heat amount, and the heat storage amount in the time period shown in FIGS. 2 and 3 and the information displayed on the display 23a of the remote controller 23 will be described.
In the following, (1) 5:52 (time point c1) to 5:58, (2) 6:41 (time point c2) to 6:50, and (3) 19:39 (time point c5) to 20 Let's take a look at three time zones: 0:00.

(1) From 5:52 (at time c1) to 5:58
As shown in FIG. 2, the first hot water demand occurs at 5:52 (at the time of c1). At this time, the user has turned on the hot water supply operation switch of the remote controller 23 for washing the face, and the screen of the display 23a is turned on. The user confirms whether or not the hot water stored in the hot water tank 20 can be used with the display device 23a.
The amount of mixed hot water that can be used at the set temperature from the amount of heat stored in the hot water tank 20 can be obtained from the following equation.
Available mixed hot water amount = heat storage amount / 4.19 / (set temperature-water supply temperature);
3 to 5:52 (at time c1), the heat storage amount is 2933 (kJ). As shown in FIG. 4, the user sets the set temperature to 40 ° C., and the water supply temperature at this time is 20 ° C. For example, the amount of mixed hot water that can be used is as follows.
Available amount of mixed hot water = 2933 ÷ 4.19 ÷ (40−20) = 35.0 (liter);
In FIG. 4, it is displayed that 35 (liters) of hot water can be used.
As shown in FIG. 4, the indicator 23 a displays the water level of the bath stored in the available mixed hot water amount, the shower available time, and the hot water tap available time in characters and graphics, respectively. The water level of the bath that can be stored with the amount of hot water available, the available time of the shower, and the available time of the hot water tap can be obtained from the following equations, respectively.
Bath water level = available mixed hot water volume / bathtub volume x 10
Shower availability time = available mixed hot water volume ÷ shower water supply per unit time;
Hot water tap available time = available mixed hot water amount ÷ hot water supply amount per unit time;
The following values are obtained from the above-mentioned amount of available mixed hot water.
Bath water level = 35.0 ÷ 150 × 10 = 2.3;
Available shower time = 35.0 ÷ 10 = 3.5 (minutes);
Hot water tap availability time = 35.0 ÷ 6 = 5.8 (minutes);
FIG. 4 shows that with 35 (liter) hot water, the bath is stored up to the water level 2, the shower can be used for 4 minutes, and the hot water tap can be used for 6 minutes. It can be understood that the hot water stored in the hot water tank 20 can be used up to 6 minutes in the face washing using the hot water tap.

In addition, the heat storage amount stored in the hot water storage tank 20 changes every moment, for example, increases when the recovered heat amount is added and decreases when the hot water demand is generated. Therefore, the display on the display 23a also changes every moment with the fluctuation of the heat storage amount. For example, at 5:53 when 1 minute has passed since 5:52, the amount of hot water required is greater than the amount of stored heat to which the amount of recovered heat is added, the amount of stored heat is reduced, and the amount of available mixed hot water is less than the display at 5:52 And available time are displayed.
Similarly, the display on the display unit 23a changes from moment to moment as the amount of heat stored changes.

In addition, the actual amount of water supply per unit time of the shower and hot water tap is determined by the degree to which the user opens and closes the tap, and may differ from the value stored in advance. The second water amount sensor 47 detects the amount of water supplied from the shower or hot water tap, and can know the actual amount of water supplied per unit time when the use of the mixed hot water is started at the shower or hot water tap. In this embodiment, when the use of the mixed hot water is started in a shower or a hot water tap, the available time is calculated using the water supply amount per unit time detected by the second water amount sensor 47. Therefore, if the detected water supply amount per unit time varies, the calculated available time also changes. In addition, the display on the indicator 23a also changes as the water supply amount per unit time varies.
For example, if 3 minutes from 5:52 to 5:55 are used at 4 (liters / minute) and 1 minute from 5:55 to 5:56 are used at 8 (liters / minute), 5:55 The hot water tap available time calculated and displayed in
Hot water tap available time = (35-4 x 3) ÷ 4 = 5.8 (minutes)
The hot water tap available time calculated and displayed at 5:56 is
Hot water tap available time = (35-4 × 3-8) ÷ 8 = 1.9 (minutes)
It becomes.

The user used the hot water tap from 6:52 (c1) to 5:58 for a little over 6 minutes (6.2 minutes). Here, it is assumed that the actual water supply amount per unit time is 4 (liters / minute) in the first half of 3.1 minutes and 8 (liters / minute) in the second half of 3.1 minutes. From the above formula, the hot water demand in this time zone is the following value.
Hot water demand at hot water tap = 4 × 3.1 × (40-20) × 4.19
+ 8 * 3.1 * (40-20) * 4.19
≈ 3117 (kJ);
This value is shown in FIG.
On the other hand, the amount of heat stored in the hot water storage tank 20 at 5:52 is 2933 (kJ), and since the amount of recovered heat is only 184 (kJ) from 5:52 to 5:58, the amount of stored heat is “2933 + 184 = 3177 (kJ) ". However, since the hot water demand (3117 (kJ)) is the same value as the increased heat storage amount (3117 (kJ)), the heat storage amount is used up at 5:58 and becomes zero.

(2) From 6:41 (at time c2) to 6:50
As shown in FIG. 3, at 6:41 (time point c2), the amount of heat stored in the hot water tank 20 is restored to 2514 (kJ). At this time, the user turns on the hot water supply operation switch of the remote controller 23 for cleaning up after breakfast, and checks whether or not the hot water stored in the hot water storage tank 20 can be used with the display unit 23a.
As shown in FIG. 5, if the set temperature is 38 ° C. and the feed water temperature at this time is 20 ° C., the amount of mixed hot water that can be used is as follows.
Available mixed hot water amount = 2514 ÷ 4.19 ÷ (38−20) ≈33.3 (liter);
In FIG. 5, it is displayed that 33 (liters) of hot water can be used.
Moreover, the water level of the bath stored with the amount of mixed hot water that can be used, the shower availability time, and the hot water tap availability time are as follows.
Bath water level = 33.3 ÷ 150 × 10≈2.2;
Shower available time = 33.3 ÷ 10 ≒ 3.3 (minutes);
Hot water tap available time = 33.3 ÷ 6 ≒ 5.6 (minutes);
FIG. 5 shows that with 33 (liter) hot water, the bath is stored up to the water level 2, the shower is available for 3 minutes, and the hot water tap is available for about 6 minutes. It can be seen that the hot water in the hot water storage tank 20 can be used for about 6 minutes in the post-cleaning using the hot water tap.

Here, the user takes time to clean up and uses the hot water tap from 6:41 (c2) to 6:50 for a little less than 9 minutes (8.9 minutes). In addition, it is assumed that the actual water supply amount per unit time at this time is 6 (liters / minute). Then, the amount of hot water demand in this time zone becomes the following value.
Hot water demand at hot water tap = 6 × 8.9 × (38-20) × 4.19≈4027 (kJ);
This value is shown in FIG.
The amount of heat stored in the hot water storage tank 20 at 6:41 is 2514 (kJ), and since the amount of recovered heat is only 282 (kJ) from 6:41 (point of c2) to 6:50, the amount of stored heat is “2514 + 282. = 2796 (kJ) ". On the other hand, the demand for hot water is 4027 (kJ), which exceeds the increased amount of heat storage (2796 (kJ)). Therefore, at 6:50, the heat storage amount is used up and becomes zero.
At this time, the heat storage amount is insufficient by “4027−2796 = 1231 (kJ)”. When the heat storage amount is insufficient as described above, the controller 21 operates the hot water supply burner 56 to heat the burner heat exchanger 52 and maintain the set temperature.

(3) From 19:39 (at time c5) to 20:00
At 19:39 (at time c5), the user turns on the hot water supply operation switch of the remote controller 23 in order to start bathing. As shown in FIG. 3, the heat storage amount at this time is 36000 (kJ).
As shown in FIG. 6, if the set temperature is 42 ° C. and the feed water temperature at this time is 20 ° C., the amount of mixed hot water that can be used becomes the following value.
Available mixed hot water amount = 36000 ÷ 4.19 ÷ (42−20) ≈390.5 (liter);
As shown in FIG. 6, the display 23a displays that 391 (liters) of hot water is available.
Moreover, the water level of the bath stored with the amount of mixed hot water that can be used, the shower availability time, and the hot water tap availability time are as follows.
Bath water level = 390.5 ÷ 150 × 10≈26.0;
Available shower time = 390.5 ÷ 10 ≒ 39.1 (minutes);
Hot water tap available time = 390.5 ÷ 6 ≒ 65.1 (minutes);
Although the bath water level is 25.8 in calculation, the highest water level (full water level) is 10, so it is corrected to 10.
When the bath water level exceeds 10 in the calculation, it is also displayed how much the shower and hot water tap can be used after filling the bath.
In FIG. 6, out of 391 (liters) of the available mixed hot water amount, if 150 (liters) is used for the bathtub, the remaining 241 (liters) can be used for 24 minutes, and the hot water tap is used for 41 minutes. It has been shown to be possible.

Here, when the user changes the set temperature to 40 ° C., the amount of available mixed hot water becomes the following value.
Available amount of mixed hot water = 36000 ÷ 4.19 ÷ (40−20) ≈429.6 (liter);
As shown in FIG. 7, the display 23a displays that 430 (liters) of hot water is available.
Moreover, the water level of the bath stored with the amount of mixed hot water that can be used, the shower availability time, and the hot water tap availability time are as follows.
Bath water level = 429.6 ÷ 150 × 10≈28.6;
Available shower time = 429.6 ÷ 10≈43.0 (minutes);
Hot water tap availability time = 429.6 ÷ 6 ≒ 71.6 (minutes);
In FIG. 7, in a hot water storage of 430 (liters), the bath is stored up to water level 10, the shower is available for 43 minutes (28 minutes after filling), and the hot water tap is available for 72 minutes (47 minutes after filling). It is shown that.
When the user changes the set temperature in this way, the amount of mixed hot water that can be used changes. At the same time, the available time at each hot water use location also changes.

The hot water demand for hot water filling from 20:00 to 19:39 (at time c5) is as follows.
Hot water demand in bath = 150 × (42−20) × 4.19≈13827 (kJ);
This value is shown in FIG.
The amount of heat stored at 19:39 (at time c5) is 36000 (kJ), and since the amount of heat recovered is 645 (kJ) from 19:39 to 20:00, the amount of stored heat is “36000 + 645 = 36645. (KJ) ". This amount of heat storage exceeds the hot water demand (13827 (kJ)). Therefore, as shown in FIGS. 2 and 3, the heat storage amount is reduced, but still remains.

As described above, according to the present embodiment, it is displayed how much mixed hot water is available from the hot water storage in the hot water storage tank at the temperature set by the user. In addition, the water level of the bath stored with the mixed hot water amount, the available time of the shower, and the available time of the hot water tap are also displayed.
From these displays, the user can use the hot water without impairing the energy saving effect.

Specific examples of the present invention have been described in detail above, but these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples illustrated above.
In this embodiment, the fuel cell system is adopted as the power generation unit, but this is not a limitation. For example, any power generation unit such as an engine drive type or a solar power generation method may be adopted.
In the present embodiment, the heat storage amount is calculated based on the thermistor detection value, the feed water temperature, and the hot water tank volume, but is not limited thereto. For example, any calculation method may be employed, such as obtaining as a difference between the heat generation amount (recovered heat amount) obtained from the operation state of the power generation unit and the heat usage amount.
In this embodiment, character display and image display on the display are adopted, but the present invention is not limited to these. For example, any display form such as lamp display or sound display may be adopted.
In addition, the technical elements described in the present specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology illustrated in the present specification or the drawings achieves a plurality of objects at the same time, and has technical utility by achieving one of the objects.

The system diagram of a hot-water supply apparatus. The figure which shows the change of warm water demand amount and heat storage amount. The table | surface which shows the amount of hot water demands, collection | recovery heat amount, and heat storage amount for every time slot | zone. The figure which shows the example of a display in the time slot | zone from 5:52 to 5:58. The figure which shows the example of a display in the time slot | zone from 6:41 to 6:50. The figure which shows the example of a display in the time slot | zone from 19:39 to 19:20. The figure which shows the example of a display in the time slot | zone from 19:39 to 19:20.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10: Hot water supply apparatus 20: Thermal storage tank, 20a: Outlet part 21: Controller 22: Auxiliary heat source machine 23: Remote control 24: Mixing unit, 24a: Water supply inlet, 24b: Mixed hot water outlet, 24c: Hot water inlet 25: Hot water filling path 26 : Water supply path, 26a: inlet 27: pouring valve 28: pressure reducing valve 30: mixing unit water supply path 31: relief valve 32: pressure release path, 32a: one end, 32b: other end 33: drainage path 34: drainage valve 35: Upper thermistor 36: Lower thermistor 39: Middle thermistor 40: Circulation pump 42: Hot water path 44: Outward thermistor 45: Return thermistor 47: Second water quantity sensor 48: Water supply thermistor 50: Hot water inlet thermistor 51: Hot water path 52: Burner heat Exchanger 54: Mixed hot water outlet thermistor 55: High cut thermistor 56: Hot water supply burner 57: Bunch burner 58: reheating heat exchanger 59: makeup water valve 60: burner heat exchanger 61: cis turn 62: cis turn water inlet path 63: hot water tap path 64: hot water tap 65: hot water thermistor 66: water level electrode, 66a: high level Switch, 66b: low level switch 67: first water amount sensor 68: systern water discharge path 69: heating pump 70: low temperature water path 70a, 70b: low temperature water branch path 71: burner upstream path 72: heating thermistor 73: high temperature water path 74 : High temperature thermistor 75: Heating terminal thermal valve 76: Heating terminal, 76a: Operation switch, 76b: Heat exchanger 77: Reheating path 78: Reheating thermal valve 79: Bathtub, 79a: Suction port, 79b: Supply Mouth 80: Bath circulation path 81: Bath water level sensor 82: Bath circulation pump 83: Hot water amount sensor 84: Bath water flow switch 85: Bath Mouth thermistor 86: Three-way valve, 86a: A port, 86b: B port, 86c: C port 87: Low temperature water return path 88: Heat storage tank path, 88a: Heat exchange coil section 89: Low temperature water return thermistor 91: Floor heater 94: Floor heating thermistor 95, 96: Floor heating thermal valve 97: Bath inlet thermistor 110: Power generation unit 112: Reformer 114: Fuel cell 116: Heat exchanger 117: Heat medium temperature sensor 118: Heat exchanger 119: Heat medium cooling fan 120: Heat medium radiator 121: Hydrogen gas supply path 122: Heat medium three-way valve, 122a: Inlet, 122b: Outlet, 122c: Outlet 124: Heat medium circulation path 125: Reserve tank 126: Combustion gas path 127 : Heat medium pump 128: Circulation path, 128a: Circulation return path, 128b: Circulation return path 129: Cooling path 131: Burner

Claims (1)

A hot water tank for storing hot water,
A heat storage amount calculating means for calculating a heat storage amount stored in the hot water storage tank at predetermined time intervals;
A hot-water supply set temperature storage means for storing a set temperature of hot water to be supplied to a hot water use location including a hot water tap for supplying hot water to a shower and bath tub and at least one other hot water tap;
A mixing unit that mixes hot water from a hot water tank and tap water, and sends mixed hot water adjusted to a hot water supply set temperature stored in a hot water set temperature storage means;
Tap water temperature detecting means for detecting the temperature of tap water;
Used in hot water usage locations based on the heat storage amount calculated by the heat storage amount calculation means at predetermined time intervals, the hot water set temperature stored in the hot water set temperature storage means, and the tap water temperature detected by the tap water temperature detection means Usable mixed hot water amount calculating means for calculating a possible mixed hot water amount at predetermined time intervals;
Hot water flow rate storage means for storing the flow rate of mixed hot water when supplying hot water to the shower and the flow rate of mixed hot water when supplying hot water to other hot water taps;
Set the hot water supply from the available mixed hot water amount calculated by the available mixed hot water amount calculation means at predetermined time intervals, the mixed hot water flow rate of the shower stored in the hot water flow rate storage means, and the mixed hot water flow rate of other hot water taps Available time calculating means for calculating the time during which hot water can be supplied to the shower and the time during which hot water can be supplied to other hot water taps at predetermined time intervals;
Combined use of the amount of available hot water mixed calculated by the available mixed water amount calculating means at predetermined time intervals, the available time of the shower calculated by the available time calculating means at predetermined time intervals, and the available time of other hot water taps When the amount of mixed hot water that can be used does not exceed the volume of the bath tub, the bath water level that can be supplied to the bath tub is displayed. Display means for displaying the available time of the shower and the available time of other hot water taps together with the value obtained by subtracting
A hot water supply device comprising:

Images