JP4126282B2 - Water heater - Google Patents

Description

  The present invention relates to an apparatus for storing hot water heated by heat generated by power generation or solar heat in a heat storage tank and supplying hot water when necessary.

If an apparatus that stores hot water in a heat storage tank and supplies hot water when necessary is used, heat energy can be obtained at a low cost and is expected to spread.
In the case of a solar heat utilization system, if the heat storage tank is enlarged, it may be possible to prevent the situation where the hot water stored in the hot water is used up, but the capital investment is excessive. In the case of a system that uses hot water to generate hot water, it is possible to prevent the occurrence of a situation where the hot water stored in the hot water is exhausted if the operation of generating electricity unnecessarily is performed. ineffective. The total efficiency of the combined heat and power supply system (cogeneration system) will not increase unless there is an operation of generating electricity and storing it with the generated heat because there is power demand. The spread of cogeneration systems that use fuel cells is urgent, but because of the high power generation efficiency of fuel cells (the ratio of power generation heat / power generation amount is low), it is often impossible to store a sufficient amount of heat. That is expected.
Therefore, in an apparatus that stores hot water in a heat storage tank and supplies hot water when necessary, a situation occurs where the stored hot water is exhausted.

In order to prepare for the situation where the hot water that has been stored is exhausted, hot water is stored in the heat storage tank and hot water is supplied when necessary. The heat storage tank that stores the hot water and the hot water and tap water from the heat storage tank Are used in combination with a mixer in which the mixing ratio can be adjusted and a water heater that heats the water that has passed through the mixer as necessary to supply hot water to the hot water use location.
In conventional equipment, while hot water at the required temperature is supplied from the heat storage tank, heating operation is not performed in the hot water heater, and hot water adjusted to the required temperature by the mixer passes through the hot water heater and uses hot water. Hot water is supplied to the location. When the hot water stored in the hot water is exhausted and the temperature of the hot water supplied from the heat storage tank is lowered, the heating operation of the water heater is started, and the hot water is heated to a necessary temperature and continuously supplied to the hot water use location.
To put it simply, when hot water stored is available, it is given priority, and when the stored hot water is used up, it begins to heat in the water heater.

JP 2003-61245 A

As long as the hot water stored in the hot water is available, the energy for obtaining the hot water cannot be saved unless it is used with priority. It can be said that the conventional method is reasonable.
However, when actually used, the user may feel uncomfortable. For example, if the user uses up the hot water stored in the middle of the shower while using the hot water stored by the user, the hot water stored in the shower will continue to be heated by the water heater. And hot water will be supplied. At this time, it is difficult to compensate for the decrease in hot water temperature caused by exhausting the hot water stored in the hot water heater, and it is avoided that the hot water temperature for the shower changes temporarily during switching. I can't. In the heat storage tank, hot water and cold water are stored in a temperature-stratified state, and when the stored hot water is exhausted, it changes rapidly to cold water. It is very difficult to compensate for the decrease in temperature with the heating amount of the water heater.

  In the present invention, the hot water stored in the hot water can be used so that the hot water stored in the hot water heater remains unusable even though it is not necessary to heat in the water heater. We propose a technology that prevents the occurrence of the problem and prevents the user from feeling uncomfortable when the stored hot water is used up.

The hot water supply device created in the present invention includes a heat storage tank that stores hot water, a mixer that mixes hot water and tap water from the heat storage tank, and the mixing ratio of which can be adjusted, and water that has passed through the mixer as needed. Use a water heater that heats and supplies hot water to the hot water. This is the same as the conventional hot water supply apparatus.
The hot water supply device created in the present invention includes a hot water supply demand record storage device that stores the actual time of hot water supply demand time and the amount of hot water supply when heat is supplied from the heat storage tank according to the hot water supply demand, and the following control device. It is characterized by having. The control device at a predetermined timing in a day, that the predetermined hot-water demand Ryo以is generated according to one of the hot water demand during the day is predicted from the stored contents of the hot-water demand performance storage device that the whether to determine, if it is predicted, it determines information on whether the or unutilized amount thermal storage of the heat storage tank by the hot water demand as possible is used remains. The control device (1) allows the hot water heater to perform a heating operation before the hot water supply demand time of the hot water supply demand stored in the hot water supply demand record storage device when it can be used. When the usage remains, the hot water heater is prohibited from performing the heating operation before the hot water supply demand time of the hot water supply demand stored in the hot water demand actual storage device. The term “one day” here is not limited to 0:00 to 24:00 as a time, but includes the meaning that one day is from the start of use of the hot water supply device to the end of use by the user. Here, “hot water supply” means both supplying hot water directly and conveying heat to a circulation destination by circulating hot water as a heat medium (the same applies hereinafter).

Incidentally, in the above of the water heater, the predetermined hot water demand is, the hot water supply to the hot water supply and hot water type heating system to accumulate hot water to the bathtub, that is set to hot water demand that can be identified from other hot water supply.
In this case, the hot water stored during hot water operation or heating operation will be used up, and it will not be heated unnecessarily, or it may cause discomfort to the user due to temporary temperature fluctuations. Absent.

If the heat storage tank is to store hot water heated by the heat generated by power generation, that is, if it has a generator that generates power in response to power demand, the results of changes in power generation over time It is preferable to provide a power generation record storage device that stores.
Then, the control device includes a heat storage amount at the present time, the power generation amount of up to hot water demand time stored in the hot-water demand performance storage device, may be predicted calculate amount of heat stored in the hot-water demand time. Furthermore, when the can on the predetermined hot-water demand Ryo以is generated according to one of the hot water demand during the same day is predicted from the stored contents of the hot-water demand performance storage device, stored in the hot-water demand performance storage device and a hot water demand and the predicted calculated heat storage amount of the hot water demand are, heat storage of the heat storage tank by the hot water demand may determine whether the whether the unutilized fraction remains as possible is utilized.

In the hot water supply apparatus described above, it is preferable that the hot water supply demand result storage device and / or the power generation result storage device store the results for each day of the week, and the control device performs control using the results of the same day of the week.
On the same day, the same heat supply is often performed. For this reason, when the hot water supply demand record storage device and / or the power generation record storage device stores the results for each day of the week and the control device uses the results of the same day of the week, the control can be performed more accurately.

In the hot water supply apparatus described above, when hot water supply demand for the hot water type heating apparatus is stored in the hot water supply demand record storage device, control for performing preheating operation for circulating hot water through the hot water circulation path prior to the hot water supply demand time Preferably means are added.
If such preheating operation is performed, the heating start-up time can be shortened.

Preferred embodiments of the present invention will be described.
(Form 1)
A heat storage tank for storing hot water,
A water heater that heats the hot water for circulation heated by the hot water in the heat storage tank as needed and supplies heat to the hot water heater,
A heat supply record storage device that stores the record of the time when the water heater started supplying heat to the hot water heating device;
When the heat supply start time is stored in the heat supply record storage device when the heat supply start time is stored in the hot water heating device, the hot water supply device is provided with a control means for performing a preheating operation for circulating the hot water in the hot water circulation path prior to the start time. .
According to this hot water supply apparatus, since the heating apparatus can be preheated before the start of heating, the heating start-up time at the start of heating can be shortened.
(Form 2)
The heat supply record storage means stores the record for each day of the week,
A control means controls using the results of the same day of the week.
Heating is often started at similar times on the same day of the week. Therefore, according to said hot water supply apparatus, heating start time can be estimated more correctly.

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 heat storage tank 20, an auxiliary heat source device 22, a mixing unit 24, a plurality of paths that connect these, a controller 21, and the like.
A water supply path 26 for supplying tap water to the heat storage tank 20 is connected to the bottom of the heat storage 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 heat storage tank 20 and the mixing unit 24 to a predetermined pressure regulation value. When the hot water in the heat 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 heat storage tank 20 decreases, tap water is supplied to the heat storage 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 top of the heat storage 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 heat storage 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 heat storage tank 20.
The bottom of the heat storage 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 heat storage 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 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. The remote controller 23 is provided with switches and buttons for operating the hot water supply device 10, a liquid crystal display for displaying the operating state of the hot water supply device 10, and the like.

The heat storage tank 20 is connected to the power generation unit 110 through 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 heat storage tank 20. The circulation outward path 128 b is connected to the lower part of the heat storage 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 from the bottom of the heat storage tank 20. The hot water sucked out from the heat 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 flows through the circulation return path 128 a and returns to the upper part of the heat storage tank 20. In this way, the hot water sucked out from the bottom of the heat storage tank 20 is heated by the heat exchangers 116 and 118 of the power generation unit 110 to become a higher temperature, and circulation that is returned to the upper part of the heat storage tank 20 is performed. Hot water is stored in the heat storage tank 20. When high-temperature hot water is supplied from the power generation unit 110 to the heat storage tank 20 in a state where the temperature in the heat storage tank 20 is low (the heat storage tank 20 is not fully stored), the supply is supplied to the upper part of the heat storage tank 20. Since it is performed, a high temperature hot water layer (temperature stratification) is formed in the upper part of the hot water stored in the heat storage tank 20. The temperature of the hot water along the depth direction of the heat storage tank 20 is drastically lowered when it becomes deeper than the temperature stratification. When the supply of high-temperature hot water to the heat storage tank 20 is continued, the thickness (depth) of the temperature stratification gradually increases, and in the state where the heat storage tank 20 is fully stored, hot heat water is added to the entire heat storage tank 20. Will be accumulated. By forming the temperature stratification, high-temperature hot water is sent out from the outlet 20a provided at the uppermost part of the heat storage tank 20, even if the heat storage tank 20 is not fully stored.
A forward thermistor 44 that detects the temperature of the hot water sucked from the heat 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 heat storage tank 20 is attached 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 heat storage 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 heat storage tank 20. The intermediate thermistor 39 detects the intermediate temperature of the heat storage tank 20. The lower thermistor 36 detects the lower temperature of the heat storage 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 hot water outlet 24b, a first water amount sensor 67, a hot water inlet thermistor 50, a water supply thermistor 48, a hot water outlet thermistor 54, a high-cut thermistor 55, and the water inlet 24a already described. The outlet 20 a of the heat storage 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 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 hot water outlet thermistor 54 and the high cut thermistor 55 detect the temperature of the hot water flowing out from the 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 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 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 heat storage tank 20 and tap water (cold water) is adjusted. When the mixing ratio between the hot water from the heat storage tank 20 and the tap water is adjusted, the temperature of the hot water flowing out from the 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 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 opens 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.
A hot water outlet 24 b of the mixing unit 24 and a burner heat exchanger 52 (described later) of the auxiliary heat source machine 22 are connected by a hot water path 51. A second water amount sensor 47 is attached to the 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.
Hot water flows from the mixing unit 24 into the burner heat exchanger 52 via the hot 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 in which the hot water supply burner 56 operates will be described in detail later.

From the middle of the 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 heat storage tank path 88 that connects the A port 86 a of the three-way valve 86 and the middle of the low-temperature water return path 87 is provided. In the heat storage tank path 88, a heat exchange coil portion 88a passing through the upper part of the heat storage 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 are communicated, the hot water from the low temperature water path 70 bypasses the heat storage 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 86a and the C port 86c communicate with each other, the hot water from the low temperature water path 70 flows through the heat storage tank path 88. The hot water flowing through the heat storage tank path 88 is heated by the hot water stored in the upper part of the heat storage 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 heat storage tank path 88 only when the hot water stored in the upper part of the heat storage tank 20 can heat the heat exchange coil portion 88a of the heat storage tank path 88.

The hot water supply apparatus 10 can prevent the hot water in the heat storage tank 20 from being used up, can suppress fluctuations in the hot water supply temperature, and can shorten the heating start-up time. Hereinafter, the structure which implement | achieves them is demonstrated.
The graph of FIG. 2 shows the electric power demand generated for the power generation unit 110, the hot water supply demand generated for the hot water supply device 10, and the amount of heat stored in the heat storage tank 20 of the hot water supply device 10 for a certain day. ing. The horizontal axis of the graph is time, the left vertical axis is power demand (Wh), and the right vertical axis is hot water supply demand (kJ) and heat storage amount (kJ). Electric power demand is shown by a solid line. The amount of stored heat is indicated by a dotted line. Hot water demand is indicated by vertical bars.
The power generation unit 110 is operated so as to supply electric power according to electric power demand (electric power load). As already described, when the power generation unit 110 is operated, the hot water heated by the power generation unit 110 is stored in the heat storage tank 20 of the hot water supply device 10, whereby heat storage is performed in the heat storage tank 20. As the power generation unit 110 is operated, the amount of heat stored in the heat storage tank 20 increases. When hot water supply demand occurs and the hot water in the heat storage tank 20 is consumed, and the hot water supply demand exceeds the increase in the heat storage amount, the heat storage amount in the heat storage tank 20 decreases. For example, in FIG. 2, the heat storage amount peaks at around 16:30 (hereinafter described as “16:30”). In this case, the hot water supply demands 150 and 151 are generated before the heat storage amount peaks at “16:30”, but the demand is small and the heat storage is performed by the hot water supplied from the power generation unit 110. Since the amount of heat applied to the tank 20 is greater, the amount of stored heat increases. And when the hot water supply demand 152 occurs, the amount of stored heat decreases. Even if the heat storage amount decreases, the hot water supply demand 152 is small, so the heat storage amount of the heat storage tank 20 remains above the hot water supply demand 152. That is, the hot water supply is completed before the temperature stratification formed in the heat storage tank 20 is used up. Small hot water demands, such as hot water demands 150, 151, 152, occur when using a shower or hot water from a hot water tap.
The heating demand for supplying hot water to the heating system is generated in the same manner as the hot water supply demand shown in FIG.

When a large hot water supply demand occurs like the hot water supply demand 153 generated around “19:30”, the heat storage amount of the heat storage tank 20 falls below the hot water supply demand. That is, the temperature stratification formed in the heat storage tank 20 is used up. When the temperature stratification of the heat storage tank 20 is used up, the temperature of the hot water sent out from the heat storage tank 20 decreases rapidly. A large demand for hot water supply is generated by hot water filling the bathtub 79 or the like.
When the temperature stratification of the heat storage tank 20 is used up, the temperature of the hot water sent out from the heat storage tank 20 decreases rapidly. When the temperature of the hot water delivered from the heat storage tank 20 decreases, the hot water thermistor 65 detects a value equal to or lower than the hot water supply set temperature. The hot water supply set temperature is set by operating the remote controller 23. When the hot water supply thermistor 65 detects a value equal to or lower than the hot water supply set temperature, the controller 21 operates the hot water supply burner 56 to heat the burner heat exchanger 52 to maintain the hot water supply temperature. However, if the hot water supply burner 56 is operated after the hot water thermistor 65 detects a value equal to or lower than the hot water supply set temperature, it is inevitable that the operation is delayed. If there is a delay in the operation of the hot water supply burner 56, the hot water supply temperature once decreases and then returns to a high temperature.
Even if such fluctuations in the hot water supply temperature occur when the bathtub 79 is filled with hot water, no particular problem occurs. However, if the hot water temperature fluctuates when using a shower or hot water from a hot water tap, the user feels uncomfortable. The hot water supply temperature fluctuates when hot water supply is performed using a shower or hot water tap with a small demand for hot water supply, when the amount of heat stored in the heat storage tank 20 is small. In such a case, even if hot water supply is performed using a shower or a hot water tap that has a small demand for hot water supply, the temperature stratification is used up halfway, and the hot water supply temperature fluctuates. This hot water supply apparatus 10 prevents the user from feeling uncomfortable by preventing fluctuations in the hot water temperature during hot water supply using a shower or a hot water tap. Further, when it is determined whether or not the hot water in the heat storage tank 20 is used up at the end of the day, and the operation of the hot water supply burner 56 and the heating burner 57 is controlled based on that, the hot water in the heat storage tank 20 is not used up (used). It is possible to prevent waste that remains).

  In the conventional hot water supply apparatus, hot water is supplied to the low temperature water path 70 and the high temperature water path 73 after the user operates the remote controller 23 or the operation switch 76 a of the heating terminal 76. Therefore, even if the remote controller 23 is operated, the floor heated by the floor heater 91 is not immediately warmed, and even if the operation switch 76a of the heating terminal 76 is operated, the heating terminal 76 immediately blows out hot air. Absent. That is, the heating start-up is slow. If the floor is not immediately warmed by operating the remote controller 23, or if the heating terminal 76 does not blow hot air immediately by operating the operation switch 76a, the user will feel stress. The hot water supply apparatus 10 can prevent such a problem.

In order to suppress fluctuations in the hot water supply temperature and shorten the heating start-up time, the controller 21 executes a hot water supply learning process S10, a heating learning process S30, a hot water supply temperature stabilization process S40, and a heating system pre-heat treatment S70. These processes are executed in parallel. Hereinafter, each processing will be described.
As shown in FIG. 3, in the first process S12 of the hot water supply learning process S10, it is determined whether or not a hot water supply demand has occurred. For this determination, a detection signal of the second water amount sensor 47 or the hot water amount sensor 83 provided in the hot water path 51 is used. When the second water amount sensor 47 detects a water flow, it is determined that a hot water supply demand has occurred. When the second water amount sensor 47 does not detect the water flow, it is determined that no hot water supply demand has occurred. If it is determined in S12 that no hot water supply demand has occurred (NO), the process waits as it is. If it is determined in S12 that a hot water supply demand has occurred (YES), S14 is executed. In S14, the date, day of the week, and time when hot water supply demand is generated (started) are stored. In S16 subsequent to S14, the hot water demand is calculated and stored in association with the date, day of the week, and time when the hot water demand occurred (how to calculate the hot water demand will be described in detail later). To do).
Subsequent to S16, S18 is performed. In S18, it is determined whether or not the hot water supply demand has ended. If it is determined in S18 that the hot water supply demand has not ended (NO), S16 is executed again. That is, the calculation of the hot water supply demand is continued until the hot water supply demand ends. If it is determined in S18 that the hot water supply demand has ended (in the case of YES), the process returns and the processes from S12 onward are performed again.
In this way, whenever hot water demand occurs, the hot water demand is stored as a hot water learning result corresponding to the date, day of the week, and time of occurrence.

  FIG. 4 illustrates the hot water demand stored in correspondence with the date of occurrence, day of the week, and time. The hot water supply demand on Friday, December 5 corresponds to the graph of FIG. For example, the first hot water supply demand on Friday, December 5 occurs at “5:52”, and the hot water supply demand at that time is 3100 (kJ). The largest hot water supply demand was 26120 (kJ) generated at “19:39”. The last hot water demand on that day was 3750 (kJ) generated at “20:44”.

The hot water supply demand used in the hot water supply learning process S <b> 10 described above can be calculated by different methods based on various values detected by the hot water supply apparatus 10. These calculation methods will be specifically described in (1) to (7) described below.
(1) Hot water supply demand is calculated based on detection values of the hot water thermistor 65, the water supply thermistor 48, and the first water amount sensor 67;
In the following calculation formula, “detected value of the hot water thermistor 65” and the like are simply abbreviated as “hot water thermistor”. Other detection values are described in the same manner.
Hot water supply demand (per unit time) is given by the following equation.
Hot water demand (per unit time) = 4.19x
(Tapping hot water thermistor-water supply thermistor) x first water amount sensor;
“4.19” in the above formula is the specific heat of water (kJ / (liter · K)).
For example, when the detection value of the hot water thermistor 65 is 45 (° C.), the detection value of the water supply thermistor 48 is 20 (° C.), and the detection value of the first water amount sensor is 10 (liters / minute), the hot water supply demand (unit time) The hit is as follows.
Hot water demand (per unit time) = 4.19 x (45-20) x 10
= 1047.5 (kJ / min);
The product of the hot water supply demand (per unit time) and the time during which the hot water supply continues is the hot water supply demand for one time. For example, if hot water supply continues for 10 minutes, the hot water supply demand during that time will be the following value.
Hot water demand = 1047.5 × 10 = 10475 (kJ);

(2) The hot water supply demand can also be calculated by the following equation in which the first water amount sensor in the equation (1) is replaced with the second water amount sensor 47. The following formula is established when the replenishing water valve 59 is closed and all of the hot water sent from the mixing valve 24 passes through the burner heat exchanger 52.
Hot water demand (per unit time) = 4.19x
(Tapping hot water thermistor-water supply thermistor) x second water amount sensor;
(3) Hot water supply demand is calculated based on the hot water supply set temperature of the remote controller 23, the water supply thermistor 48, and the detection values of the first water amount sensor;
The hot water supply apparatus 10 supplies hot water according to a hot water supply set temperature set by the user operating the remote controller 23. Therefore, the hot water supply demand (per unit time) is given by the following equation.
Hot water demand (per unit time) = 4.19x
(Hot water set temperature-water supply thermistor) x first water amount sensor;
For example, when the hot water supply set temperature of the remote controller 23 is 40 (° C.), the detection value of the water supply thermistor 48 is 18 (° C.), and the detection value of the first water amount sensor is 12 (liters / minute), the hot water supply demand (unit time) The hit is as follows.
Hot water demand (per unit time) = 4.19 x (40-18) x 12
= 1106.2 (kJ / min);
(4) The hot water supply demand can also be calculated by the following equation in which the first water amount sensor in the equation (3) is replaced with the second water amount sensor. The following formula is established when the replenishing water valve 59 is closed and all of the hot water sent from the mixing valve 24 passes through the burner heat exchanger 52.
Hot water demand (per unit time) = 4.19x
(Hot water set temperature-water supply thermistor) x second water amount sensor;

(5) Estimate hot water demand based on burner command current value or hot water fan command value;
The hot water supply burner 56 is controlled by the controller 21 to burn, and heats the hot water supply via the burner heat exchanger 52. At this time, the controller 21 controls the gas input by outputting the burner command current value to a proportional valve (not shown) that supplies gas to the hot water supply burner 56. Here, “gas input” means the amount of heat per unit time given to the hot water by the hot water supply burner 56, that is, the demand for hot water supply (per hour). The gas input corresponding to the burner command current value is known. Therefore, the gas input can be estimated from the burner command current value output from the controller 21 to the hot water supply burner 56.
The hot water supply device 10 includes a hot water supply fan (not shown). When the hot water supply fan is activated, combustion air for gas combustion is blown by the hot water supply burner 56. The hot water supply fan changes the strength of blowing air according to the hot water supply fan command value output by the controller 21. The hot water supply fan command value corresponds to the gas input. Therefore, the gas input can be estimated from the hot water supply fan command value output from the controller 21 to the hot water supply fan.
FIG. 5 illustrates the burner command current value and hot water supply fan command value corresponding to the gas input for each burner combustion state. As described above, the gas input corresponds to the hot water supply demand. Therefore, for example, when the burner combustion state is “large combustion” and the burner command current value is 163 (mA), it can be estimated that the hot water supply demand at that time is 3068 (kJ / min). For example, when the burner combustion state is “small combustion” and the hot water supply fan command value is 175 (Hz), it can be estimated that the hot water supply demand at that time is 301 (kJ / min).

(6) Hot water supply demand is calculated based on detection values of the bath inlet thermistor 97, the water supply thermistor 48, and the hot water amount sensor 83;
When hot water is filled in the bathtub 79, the hot water supply demand can be calculated by the following equation.
Hot water demand = 4.19 x (bath entrance thermistor-water thermistor)
× Integrated value of hot water filling sensor;
The integrated value of the hot water filling amount sensor in the above formula is an integrated value of values detected by the hot water filling amount sensor 83 from the start to the end of hot water filling, and corresponds to the hot water filling amount to the bathtub 79. To do.
For example, when the detected value of the bath inlet thermistor 97 is 39 (° C.), the detected value of the water supply thermistor 48 is 21 (° C.), and the integrated value of the hot water filling amount sensor 83 is 200 (liters), the hot water supply demand is low. It becomes like the formula.
Hot water demand = 4.19 x (39-21) x 200
= 15084 (kJ);
(7) Calculate hot water supply demand based on the bath set temperature of the remote controller 23, the detected temperature of the water supply thermistor 48, and the bath set water level of the remote controller 23;
The hot water supply apparatus 10 supplies hot water at a temperature (bath set temperature) set by the user by operating the remote controller 23 to the bathtub 79. Further, the user can select the bath setting water level from “1 to 9” by operating the remote controller 23. When the bath setting water level is selected, the bathtub 79 is filled with a filling amount corresponding to the bath setting water level. Therefore, when hot water is filled in the bathtub 79, the hot water supply demand can be calculated by the following equation.
Hot water demand = 4.19 x (bath set temperature-water thermistor) x
The amount of water filling according to the bath setting water level;
FIG. 6 illustrates the relationship between the bath setting water level and the amount of hot water filling. For example, when the bath setting water level is “5”, the hot water filling amount is 180 (liters). In this case, assuming that the bath set temperature of the remote controller 23 is 40 (° C.) and the detected value of the water supply thermistor 48 is 19 (° C.), the hot water supply demand is expressed by the following equation.
Hot water demand = 4.19 x (40-19) x 180 = 15838.2 (kJ);
Note that the hot water supply demand can also be calculated using “the amount of hot water estimated from the detection value of the bath water level sensor 81” instead of “the amount of hot water according to the bath setting water level” in the above equation.

In addition to calculating hot water demand, heating demand can also be calculated. In this case, the calculation result of the heating demand is stored, and the calculation result is added to the prediction of the hot water supply demand in the hot water supply stabilization process S40 described later. Specifically, the heating demand is calculated as described below.
(1) The heating demand is calculated using the high temperature thermistor 74, the heating thermistor 72, and the heating flow rate;
The heating demand is given by the following equation.
Heating demand = 4.19 x (high temperature thermistor-heating thermistor) x heating flow rate;
The controller 21 controls the rotation speed of the heating pump 69 according to the system in which heating is performed. The heating system here refers to a system that supplies hot water to the heating terminal 76 (hereinafter referred to as “hot air heating system”) and a system that supplies hot water to the floor heater 91 (hereinafter referred to as “floor heating system”). ")". For example, when heating is performed in the hot air heating system, the heating pump 69 is rotated at 225 (Hz). For example, when heating is performed in the hot air heating system and the floor heating system, the heating pump 69 is rotated at 275 (Hz). The number of rotations of the heating pump 69 and the heating flow rate corresponding to the number of operating systems are known. Therefore, the heating flow rate can be estimated from the heating system that performs heating.
For example, the detection value of the high temperature thermistor 74 is 65 (° C.), the detection value of the heating thermistor 72 is 55 (° C.), heating is performed in the hot air heating system, and the heating pump 69 rotates at 225 (Hz). When the corresponding heating flow rate is 3.5 (liters / minute), the heating demand (per unit time) is as follows.
Heating demand (per unit time) = 4.19 x (65-55) x 3.5
= 146.7 (kJ);
(2) Estimate heating demand based on heating burner command current value or heating fan command value;
The heating burner command current value and the heating fan command value correspond to the gas input to the burner heat exchanger 60 in the same manner as the “calculation of hot water supply demand in (5)” above. Therefore, the heating demand can be estimated from the heating burner command current value and the heating fan command value.

The heating learning process S30 will be described.
As shown in FIG. 7, in the process S32 of the heating learning process S30, it is determined whether or not the heating operation is started. Specifically, when the controller 21 outputs an operation command to the heating pump 69, it is determined that the heating operation has started. If it is determined that the heating operation is not started in S32 (in the case of NO), the process waits as it is. When it is determined that the heating operation is started in S32 (in the case of YES), the process proceeds to S34.
In S34, the date, day of the week, and time when the heating operation is started, and which heating system (warm air heating system, floor heating system) is used for heating are stored. It is judged from the information regarding the heating system selected with the remote control 23 which heating system was heated. Further, when the operation switch 76a of the heating terminal 76 is turned on without using the remote controller 23, it is determined by the operation signal of the operation switch 76a input to the controller 21 that heating has been performed in the hot air heating system. To do.
After processing S34, return and execute S32 again.

  FIG. 8 illustrates the heating learning result stored by executing the above-described heating learning process S30. For example, on January 16 (Friday), heating is started in the hot air heating system at “5:32”. Following the heating operation system, heating is started in the floor heating system at “6:10”. In this manner, the heating operation start time corresponding to the date and day of the week and the heating system in which the heating is performed are sequentially stored.

The hot water supply temperature stabilization process S40 will be described.
As shown in FIG. 9, in the first process S42 of the hot water supply temperature stabilization process S40, it is determined whether or not the operation of the hot water supply apparatus 10 has been started. When it is determined in S42 that the operation of the hot water supply apparatus 10 has not been started (in the case of NO), the process waits as it is. If it is determined in S42 that the operation of the hot water supply apparatus 10 has been started (in the case of YES), S44 is performed. Note that the determination in S42 is provided on the assumption that the operation start of the hot water supply device 10 is repeated every day. If the hot water supply device 10 is continuously operated, S42 is not provided. S44 may be executed at the same time every day (for example, 1 am).
In S44, it is determined whether or not occurrence of hot water supply demand (Y (kJ)) (hereinafter referred to as “higher than specified hot water supply demand”) that is greater than or equal to a predetermined specified hot water supply demand is predicted. This determination is the same as the day of the week, which is stored by executing the hot water supply learning process S10, and determines whether or not the occurrence of a hot water supply demand (Y (kJ)) more than a predetermined time is predicted. Use hot water learning results for the day of the week. When the hot water supply demand (Y (kJ)) exceeding the specified value is stored in the hot water supply learning result one week ago, it is determined that the occurrence of the hot water supply demand (Y (kJ)) or higher than the specified value is predicted. In the following, the description will be made assuming that the hot water supply demand is equal to or higher than the specified value = 15000 (kJ).

  A large hot water supply demand such as a hot water supply demand (Y (kJ)) or more than specified occurs when hot water is filled in the bathtub 79 or when floor heating is performed. There is a high possibility that the hot water filling and the floor heating to the bathtub 79 are performed at the same time as the same day of the past. This is because a person living in a house where the hot water supply device 10 is installed repeats the same life pattern every same day of the week. For example, in an office worker family, a bath is filled in the bathtub from Monday to Friday according to the time when the husband returns home. For this reason, in the home where the master's return time does not fluctuate so much, the bathtub is filled with water almost at the same time. On the other hand, since the master does not go to work on Saturday and Sunday, the bath is filled with water at a time earlier than Monday to Friday. Therefore, when the hot water supply learning result of the same day of the past is used, the time when the hot water is filled in the bathtub 79 can be predicted in consideration of the variation factor due to the different days of the week. Of course, since the hot water supply demand varies depending on seasonal factors, it is preferable to use the latest hot water learning result on the same day rather than the hot water learning result on the same day in the past. In the hot water supply demand prediction described above, the hot water supply learning result of one week ago is used, but from the average hot water supply learning result of a plurality of past same days (for example, the same day of the week before and two weeks ago) The time may be predicted. If it does in this way, hot water supply demand can be predicted with higher reliability.

If it is determined in S44 that the occurrence of hot water supply demand (Y (kJ)) equal to or higher than the specified hot water supply demand is not predicted (in the case of NO), the hot water supply temperature stabilization process S40 is terminated. As shown in FIG. 4, a hot water supply demand of 26120 (kJ) is generated at “19:39” on Friday, December 5th. Therefore, when S44 of hot water supply temperature stabilization processing S40 is executed on December 12 (Friday), one week after December 5 (Friday), hot water supply that exceeds the specified hot water supply demand (15000 (kJ)). It is determined that demand (Y (kJ)) is predicted. If it is determined in S44 that a hot water supply demand (Y (kJ)) greater than the specified hot water supply demand is predicted (YES), the process proceeds to S46.
In S46, the heat storage amount (Z (kJ)) at the time (after X (minutes)) when the hot water supply demand (Y (kJ)) equal to or greater than the specified hot water supply demand is predicted (hereinafter, this heat storage amount is predicted heat storage amount ( Z (kJ))). For example, when the operation of the power generation unit 110 is started at “4:10”, the hot water supply demand (26120 (kJ)) exceeding the specified value is “19:39”, so X = 929. Predict the amount of heat storage after (minutes).
In predicting the predicted heat storage amount (Z (kJ)), the amount of heat stored in the heat storage tank 20 at the time of the prediction (hereinafter referred to as “predicted heat storage amount”) and the hot water supply demand above the specified level (Y (KJ)) is generated, and the total amount of heat stored in the heat storage tank 20 (hereinafter referred to as “additional heat storage amount”) is calculated. That is, the predicted heat storage amount (Z (kJ)) is obtained from the following equation.
Predicted heat storage amount = Predicted heat storage amount + Additional heat storage amount;

The predicted heat storage amount includes the detected values of the upper thermistor 35, the intermediate thermistor 39, the lower thermistor 36, the water supply thermistor 48, the upper volume of the heat storage tank 20 (hereinafter referred to as “heat storage tank upper volume”), the heat storage tank Using the following equation, the volume of the intermediate portion of 20 (hereinafter referred to as “heat storage tank intermediate volume”) and the volume of the lower portion of the heat storage tank 20 (hereinafter referred to as “heat storage tank lower volume”) are obtained. Can do.
Predicted heat storage amount = {(Upper thermistor-Feed water thermistor) x Heat storage tank upper volume
+ (Intermediate thermistor-feed water thermistor) x heat storage tank intermediate volume
+ (Lower thermistor-feed water thermistor) x heat storage tank lower volume}
X 4.19;
For example, the detected value of the upper thermistor 35 is 65 (° C.), the detected value of the intermediate thermistor 39 is 60 (° C.), the detected value of the lower thermistor 36 is 25 (° C.), and the detected value of the water supply thermistor 48 is 20 (° C.). Suppose that Further, it is assumed that the heat storage tank upper volume is 30 (liters), the heat storage tank middle volume is 30 (liters), and the heat storage tank lower volume is 50 (liters). In this case, the predicted heat storage amount is the following value.
Predicted time heat storage amount = {(65-20) × 30 + (60-20) × 30
+ (25-20) × 50} × 4.19
= 11732 (kJ);
Note that the predicted heat storage amount = 11732 (kJ) does not match the heat storage amount shown in the graph of FIG.

The additional heat storage amount is the detected value of the return thermistor 45 and the outward thermistor 44 and the flow rate of hot water circulating between the power generation unit 110 and the heat storage tank 20 by the operation of the circulation pump 40 (hereinafter referred to as “circulation flow rate”). ) And the time (X (minutes)) until the hot water supply demand (Y (kJ)) exceeds the specified level. The relationship shown in FIG. 10 exists between the rotation speed (Hz) of the circulation pump 40 and the circulation flow rate (liter / minute). Therefore, the circulation flow rate at that time can be estimated from the rotation speed command value output from the controller 21 to the circulation pump 40. For example, when the circulating pump 40 is commanded to rotate at a rotational speed command value of 100 (Hz), the circulating flow rate is estimated to be 0.6 (liters / minute).
The additional heat storage amount is given by the following equation.
Additional heat storage amount = 4.19 x (return thermistor-outbound thermistor)
X Circulating flow rate x X;
X in the above formula is the time (minutes) until the hot water supply demand (Y (kJ)) exceeds the specified level.
For example, when the detection value of the return thermistor 45 is 60 (° C.), the detection value of the outward thermistor 44 is 30 (° C.), the circulation flow rate is 0.3 (liter / minute), and X is 746 (minute), The additional heat storage amount is as follows.
Additional heat storage amount = 4.19 × (60-30) × 0.3 × 746
= 28131 (kJ);
This additional heat storage amount = 28131 (kJ) is not consistent with the heat storage amount shown in the graph of FIG.
Accordingly, the predicted heat storage amount is the following value.
Predicted heat storage amount = predicted heat storage amount + additional heat storage amount = 11732 + 28131
= 39863 (kJ);

Rather than calculating the additional heat storage amount as described above, the past additional heat storage amount (for example, the additional heat storage amount corresponding to the passage of time one week ago) is learned, and the additional heat storage is performed using the learning result. The amount can also be estimated. Also,
Furthermore, the additional heat storage amount can be estimated based on the power generation amount of the power generation unit 110. This is because the information related to the power generation amount is input to the controller 21, and the power generation amount corresponds to the heat amount (additional heat storage amount) given to the hot water circulated between the power generation unit 110 and the heat storage tank 20. For example, when the power generation amount of the power generation unit 110 is 1 (kW), the hot water circulating between the heat storage tanks 20 is given a heat amount of 4 (kJ), and when the power generation amount is 2 (kW), the hot water is An amount of heat of 8 (kJ) is given. The additional heat storage amount can be estimated using the correlation between the amount of heat generated and the amount of heat given to the hot water circulating between the heat storage tanks 20. In this case, since the amount of heat given to the hot water is an additional heat storage amount, the element of heat radiation from the heat storage tank 20 to the outside is not considered. On the other hand, in the calculation of the additional heat storage amount described above, the detection value of the forward thermistor 44 provided in the circulation outward path 128b through which the hot water returning from the heat storage layer 20 to the power generation unit 110 passes is used. Heat dissipation from the outside to the outside is considered indirectly. Therefore, if the additional heat storage amount is estimated based on the power generation amount of the power generation unit 110, the estimation accuracy decreases with the passage of time. In order to prevent this, it is preferable to reset the estimated heat storage amount. Specifically, when the detected temperatures of the feed water thermistor 48 and the hot water inlet thermistor 50 become equal, the additional heat storage amount is reset to zero assuming that the heat storage amount of the heat storage tank 20 becomes zero, and a new additional heat storage from that point. Start quantity estimation.

  As shown in FIG. 9, S48 is executed following S46. In S48, it is determined whether or not the predicted heat storage amount (Z (kJ)) is smaller than the specified hot water supply demand (Y (kJ)). When the predicted heat storage amount (Z (kJ)) is smaller than the specified hot water supply demand (Y (kJ)), the hot water supply demand (hereinafter referred to as “below the specified value”) is smaller than the specified hot water supply demand (Y (kJ)). When a large amount of “hot water supply demand”) occurs, the amount of heat stored in the heat storage tank 20 may become zero during the hot water supply demand below the specified value. When the amount of stored heat becomes zero during the hot water supply demand below the specified level, the hot water supply burner 56 operates to maintain the hot water supply temperature, but the hot water supply temperature fluctuates due to the operation delay. The hot water demand below the standard is generated by hot water supply from showers and hot water taps. Hot water supply from a shower or hot water tap is often performed randomly. When it is determined that the heat storage amount (Z (kJ)) predicted in S48 is smaller than the hot water supply demand (Y (kJ)) (in the case of YES), S50 is executed.

  When S50 is executed, the operation of the hot water supply burner 56 is permitted. Then, when a hot water supply demand occurs, the hot water supply burner 56 operates. If the operation of the hot water supply burner 56 is permitted in S50, the temperature of the hot water delivered from the mixing valve 24 is adjusted to a value “4.5 / water volume” lower than the hot water temperature set by the remote controller 23. Is done. Here, “4.5 / water volume” means a hot water supply capacity capable of raising 4.5 (liter) of water by 25 (° C.). “4.5 / water volume” is set in consideration of the heating performance of the hot water supply burner 56. The hot water supply burner 56 can raise the temperature of No. 4.5 (4.5 (liter)) water by 25 (° C.) or more. For example, when the hot water supply set temperature of the remote controller 23 is 45 (° C.), the temperature of the hot water sent out from the mixing valve 24 is adjusted to 20 (° C.), which is 25 (° C.) lower than 45 (° C.). When the hot water supply burner 56 is operated in this way, the hot water supply demand (hot water from a shower or a hot-water tap) is often less than the specified hot water supply demand (Y (kJ)) and is often randomly generated and difficult to predict. ) Occurs and the amount of stored heat becomes zero, it is possible to prevent the hot water supply temperature from fluctuating in the middle of the hot water supply demand below the specified amount. Hot water supply temperature fluctuates when the amount of heat stored in the heat storage tank 20 becomes zero during the hot water supply demand (Y (kJ)) or more than the specified value and the hot water supply burner 56 is activated, but the user does not feel it. It will not be.

  It is determined whether or not the hot water supply demand (Y (kJ)) above the total specified amount is used up at the end of the day from the predicted hot water supply demand (Y (kJ)) above, and if it is used up, the burner 56, The operation of the burners 56 and 57 may be prohibited when the operation of the burner 56 is permitted. In this way, it is possible to prevent waste that hot water remains in the heat storage tank 20 at the end of the day.

In S52 following S50, it is determined whether or not X (minutes) has elapsed. As described above, X (minutes) is the time until the hot water supply demand (Y (kJ)) exceeds the specified level. If it is determined in S52 that X (minutes) has not elapsed (NO), S50 is executed again. Therefore, the operation permission of hot water supply burner 56 is continued until X (minutes) elapses. If it is determined in S52 that X (minutes) has elapsed (in the case of YES), the flow proceeds to S54. Instead of proceeding directly to S54 when X (minutes) elapses, the process may proceed to S54 after a time when a predetermined value is added to X (minutes). This is because the hot water supply demand (Y (kJ)) above the specified level may occur slightly later than expected.
In S54, it is determined whether or not a hot water supply demand (Y (kJ)) equal to or higher than the specified hot water supply demand is predicted next. This determination is provided in the case where a plurality of hot water supply demands (Y (kJ)) greater than the specified hot water supply demand are predicted. If it is determined in S54 that a hot water supply demand (Y (kJ)) exceeding the specified level is predicted next (YES), the processes after S46 are executed again. When it is determined in S54 that the hot water supply demand (Y (kJ)) equal to or higher than the specified hot water supply demand is not predicted next (NO), the hot water supply temperature stabilization process S40 is terminated.

On the other hand, when it is determined in S48 that the predicted heat storage amount (Z (kJ)) is not smaller than the hot water supply demand (Y (kJ)) (NO), S56 is performed. When S56 is performed, the operation of the hot water supply burner 56 is disabled. Then, when a hot water supply demand occurs, the hot water supply burner 56 does not operate, and hot water is supplied with hot water from the heat storage tank 20. This is because the predicted heat storage amount (Z (kJ)) is not smaller (larger) than the specified hot water supply demand, so that the possibility that the temperature stratification of the heat storage tank 20 is completely used up even if the hot water supply demand occurs is low. Because. If the temperature stratification of the heat storage tank 20 is not used up, hot water supply with a stable hot water supply temperature can be performed to the end without heating the hot water from the heat storage tank 20 with the hot water supply burner 56. Further, by not heating the hot water from the heat storage tank 20 with the hot water supply burner 56, gas consumption due to combustion of the hot water supply burner 56 can be saved. That is, even if hot water supply demand occurs, the heat stored in the heat storage tank 20 can be used without waste and the consumption of gas can be saved.
In S58 following S56, it is determined whether or not X (minutes) has elapsed. If it is determined in S58 that X (minutes) has not elapsed (NO), S56 is executed again. If it is determined in S58 that X (minutes) has elapsed (YES), the process proceeds to S54. Similarly to the case where the operation of the hot water supply burner 56 is permitted, it is also possible to shift to S54 after the time when a predetermined value is added to X (minutes) has elapsed.

The heating system pre-heat treatment S70 will be described. As shown in FIG. 11, in the first process S72 of the heating system pre-heat treatment S70, it is determined whether or not the time has passed 1 am. If it is determined in S72 that the time has not passed 1:00 am, the process waits as it is. If it is determined in S72 that the time has passed midnight (in the case of YES), S74 is performed.
In S74, it is determined whether or not the heating demand is predicted on that day. For this determination, the heating learning result for the previous week stored by the execution of the heating learning process S30 is used. Specifically, when it is stored in the heating learning result one week ago that heating has been performed, it is determined that the heating demand is predicted. For example, when the hot water supply apparatus 10 is operated on Friday, January 23, and heating is performed on Friday, January 16, one week before, the heating demand is predicted. Determine. As shown in FIG. 8, on January 16 (Friday), heating is started in the hot air heating system at “5:32”, and heating is started in the floor heating system at “6:10”. ing. Thus, the reason why the heating demand is predicted using the heating learning result one week ago (that is, the same day of the week) is that the heating demand is likely to start at the same time as the same day of the past. By executing S72 and S74, when it is 1 am every day, it is determined whether or not heating demand is predicted on that day. In the above-described prediction of heating demand, the heating learning result of one week ago is used, but the average of the past multiple same days (for example, the same day of the week before, two weeks ago, and three weeks ago) The heating demand can also be predicted from the heating learning result.
When it is determined that the heating demand is not predicted in S74 (in the case of NO), the heating system preheat treatment S70 is terminated. When it is determined that the heating demand is predicted in S74 (in the case of YES), S76 is executed.

In S76, a (minute) is set according to the heating system in which the heating demand is predicted. When heating demand is predicted in the floor heating system, a = 30 minutes is set. When heating demand is predicted in the hot air heating system, a = 20 minutes is set. As will be described later in detail, preheating of the heating system is started when a (minute) before the time when heating demand is predicted to occur. When the heating system is preheated, the heating start-up time can be shortened. The value of a (minute) is smaller when the heating demand of the hot air heating system is predicted than when the heating demand of the floor heating system is predicted. This is because it is larger than the hot air heating system, and it takes time to preheat.
In S78, it is determined whether or not it is a (minute) before the heating demand occurs. For example, on January 16 in FIG. 8, since the generation of heating demand in the hot air heating system is predicted at “5:32”, it became “5:12” 20 minutes before that. Sometimes it is determined that it is a (minute) before the heating demand occurs. Also, since the generation of heating demand is predicted in the floor heating system at “6:10” on January 16, the heating demand is generated when it reaches “5:40” 30 minutes before that. It is determined that it is a (minute) before. If it is determined in S78 that it is not before a (minute) when the heating demand is generated (in the case of NO), the process waits as it is. If it is determined in S78 that it is a (minute) before the heating demand is generated (in the case of YES), the process proceeds to S80.

In S80, it is determined whether or not heat is stored above the heat exchange coil portion 88a provided in the upper part of the heat storage tank 20. Specifically, when the upper thermistor 35 detects a temperature of 60 (° C.) or higher, it is determined that the heat is stored above the heat exchange coil portion 88a. When it is determined in S80 that the heat is not stored above the heat exchange coil portion 88a (in the case of NO), the heating system pre-heat treatment S70 is finished as it is. This is because the heating system cannot be preheated using the hot water in the heat storage tank 20 unless the heat is stored above the heat exchange coil portion 88a. When it is determined in S80 that the heat is stored above the heat exchange coil portion 88a (in the case of YES), S82 is executed.
If S82 is performed, it will be discriminate | determined whether heating is performed. When it is determined that heating is performed in S82 (in the case of YES), the heating preheat treatment S70 is ended. This is because it is not necessary to preheat if heating is performed. When it is determined that heating is not performed in S82 (in the case of NO), S84 is performed.

  When S84 is performed, hot water is supplied to a heating system in which heating demand is predicted. For example, when the heating demand is predicted in the floor heating system, the A port 86a and the C port 86c of the three-way valve 86 are communicated, the heating pump 69 is operated, and the floor heating thermal valves 95 and 96 are opened. . When heating of only one of the floor heating systems is predicted, the floor heating thermal valve (either 95 or 96) provided in the floor heating system is opened. When the floor heating thermal valves 95 and 96 are opened, the floor heating system is preheated by the hot water. For example, when heating demand is predicted in the hot air heating system, the heating terminal thermal valve 75 is opened. When the heating terminal thermal valve 75 is opened, the hot air heating system is preheated by the hot water. Even if it is determined in S80 that the heat is not stored above the heat exchange coil portion 88a, the heating burner 57 can be operated to preheat the heating system.

In S86 following S84, it is determined whether or not the detected temperature of the floor heating thermistor 94 or the heating thermistor 72 is 30 (° C.) or higher. This determination is provided to determine the completion of preheating of the floor heating system and the hot air heating system. When it is determined that the detected temperature of the floor heating thermistor 94 or the heating thermistor 72 is not 30 (° C.) or more (in the case of NO), the process of S84 is executed again. When it is determined that the detected temperature of the floor heating thermistor 94 or the hot air heating thermistor 72 is 30 (° C.) or more (in the case of YES), S88 is performed.
In S88, the hot water supply to the heating system is stopped. When the preheating of the floor heating system is completed, the floor heating thermal valves 95 and 96 are closed. When the preheating of the hot air heating system is completed, the heating terminal thermal valve 75 is closed.
After performing S88, heating system pre-heat treatment S70 is complete | finished.

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 addition, the technical elements described in the present specification or 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. Explanatory drawing of the electric power demand corresponding to progress of time, hot-water supply demand, and heat storage amount. The flowchart of a hot water supply learning process. The table | surface which illustrates the hot water supply learning process result. The table | surface which shows a response | compatibility with a gas input, a burner command electric current value, and a hot water supply fan command value. The table | surface which shows the relationship between a bath setting water level and the amount of hot water filling. The flowchart of a heating learning process. The table which illustrates a heating learning result. The flowchart of a hot water supply temperature stabilization process. The table | surface which shows the relationship between a circulating pump rotation speed and a circulating flow rate. The flowchart of heating system pre-heat treatment.

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: 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 part 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 exchange Appliance 54: Hot water outlet thermistor 55: High cut thermistor 56: Hot water supply burner 57: Heating bar 58: Reheating heat exchanger 59: Replenishing water valve 60: Burner heat exchanger 61: Sisturn 62: Sisturn water intake 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: Systurn 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 port 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 outlet sensor Star 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: burners 150, 151, 152, 1 53, 154, 155: Hot water supply demand

Claims (4)

A heat storage tank for storing hot water,
A mixer that mixes hot water and tap water from the heat storage tank and adjusts the mixing ratio;
A water heater that heats the water that has passed through the mixer as necessary and supplies hot water to the hot water use point;
A hot water supply demand storage device that stores the hot water supply demand time and the actual amount of hot water supply when the heat is supplied from the heat storage tank according to the hot water supply demand ;
And a control device for controlling the water heater,
A control unit, at predetermined timing during the day, that the predetermined hot-water demand Ryo以is generated according to one of the hot water demand during the day is predicted from the stored contents of the hot-water demand performance storage device that the whether determined, if it is predicted, it is determined with the how the or unutilized amount thermal storage of the heat storage tank by the hot water demand as possible is utilized remain,
(1) If as possible is utilized, water heater allows the driving heat until hot water demand time of the hot-water demand stored in the hot-water demand performance storage device,
(2) When the unused portion remains, the hot water heater is prohibited from performing a heating operation until the hot water demand time of the hot water demand stored in the hot water demand record storage device ,
The predetermined hot water supply demand amount is set to a hot water supply demand amount that can distinguish hot water supply for storing hot water in a bathtub and hot water supply to a hot water heating device from other hot water supplies. It further includes a generator that generates power in response to power demand and a power generation result storage device that stores the results of temporal changes in power generation amount,
The heat storage tank stores hot water heated by heat generated with power generation,
The controller is
From the amount of heat stored at the current time and the amount of power generated up to the hot water supply demand time stored in the hot water supply demand record storage device, the heat storage amount at the hot water supply demand time is predicted and calculated,
If it is predicted from the stored contents of the hot water supply demand result storage device that the amount of hot water supply demand or more will occur in response to one hot water supply demand during the same day, the hot water supply demand result storage device stores 2. The hot water supply apparatus according to claim 1, wherein it is determined from the hot water supply demand amount of the hot water supply demand and the heat storage amount calculated by prediction whether the heat storage in the heat storage tank can be used or unused due to the hot water supply demand. The hot water supply demand result storage device and / or the power generation result storage device stores the results for each day of the week,
The hot water supply apparatus according to claim 1 or 2, wherein the control device performs control using results of the same day of the week . If hot water supply demand to the hot water heating device is stored in the hot water demand record storage device, a control means for performing preheating operation for circulating hot water in the hot water circulation path prior to the hot water supply demand time of the hot water supply demand is added. any of the water heater of claim 1, characterized in that it is 3.

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