JP2006343033A - Hot water storage type water heater - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To preferentially utilize water of intermediate temperature, and to improve usability and COP by securing stable hot water temperature in a narrow temperature range. <P>SOLUTION: This hot water storage type water heater comprises a control portion 134 having a first mixing control mode for controlling mixing by a first mixing valve 120 and use-side mixing valves 122, 125 at predetermined valve opening and closing speeds, and a second mixing control mode for controlling mixing in a state of reversing the relationship of the valve opening and closing speeds of the first mixing valve 120 and the use-side mixing valves 122, 125 with respect to the first mixing control mode, switching the first mixing control mode and the second mixing control mode under a predetermined condition when the use-side mixing valves 122, 125 are separately used, and applying the first mixing control mode when both are simultaneously used. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a hot water storage type hot water supply apparatus, and particularly to hot water mixing control using an electric mixing valve.

  Conventionally, this type of hot water storage type hot water supply device stores hot water heated by a heat pump circuit in a stratified state from the upper part of the hot water storage tank, and the hot water stored in the hot water storage tank is taken out from the upper hot water discharge pipe and mixed with the water supplied from the water supply pipe. Then, it is adjusted to a predetermined hot water temperature and supplied to a load side such as a hot water supply terminal. Further, in recent years, hot water storage type hot water supply devices having a function of using this hot water storage for bathing and heating are drawing attention. However, in this case, the hot water whose temperature has dropped after being used for bathing or heating is collected again in the hot water storage tank, so the hot water inside the hot water tank is called halfway hot water below the upper hot water. A large amount of hot and cold water will be stored. When the whole amount boiling operation is performed in a state where the intermediate temperature water is stored, the heating operation of the heat pump cycle is performed in a state where the temperature of water entering the heat pump circuit is high. Become.

  Therefore, as disclosed in Patent Document 1, as disclosed in Patent Document 1, an intermediate temperature water outlet is provided in the middle portion of the hot water storage tank, and the intermediate temperature water extracted from the outlet and the high temperature water extracted from the upper outlet pipe are disposed. A predetermined hot water temperature is ensured by mixing, and the mixed water and water supplied from a water supply pipe are mixed to obtain hot water at a set temperature with high accuracy. According to this method, the medium-temperature water can be actively taken out, so that low-temperature water can be secured below the hot water tank, and the use of high-temperature water above the hot water tank can be minimized. It is possible to suppress the boiling operation of the COP and the hot water phenomenon.

  However, when a plurality of mixing valves are specifically controlled in the configuration disclosed in Patent Document 1, there are various problems depending on the control method.

An example of the control method is disclosed in Patent Document 2. As shown in FIG. 7, the control method disclosed in Patent Document 2 uses hot water from the upper part of the hot water storage tank 2, hot water from the intermediate part of the hot water storage tank 2, and water from the water supply pipe 29 to the upstream side. Are mixed by the intermediate mixing valve 25 and the hot water mixing valve 28 on the downstream side, the valve opening is feedback controlled so that the outlet temperature of the intermediate mixing valve 25 becomes the target mixing temperature, and the outlet temperature of the hot water mixing valve 28 is set to the hot water setting temperature. In the hot water storage type hot water supply apparatus in which the valve opening is feedback controlled so that the hot water at the hot water supply set temperature is supplied, the control response speed of the feedback control of the intermediate mixing valve 25 is determined from the control response speed of the feedback control of the hot water mixing valve 28. Is also a late one.
JP 2003-240342 A JP 2004-340461 A

  According to the control method of Patent Document 2, when the intermediate mixing valve and the hot water mixing valve are controlled at the same control response speed, the feedback control of the hot water mixing valve cannot catch up with the temperature change of the hot water from the intermediate mixing valve. The response speed of the intermediate mixing valve <hot water mixing so that the control response speed of the feedback control of the hot water mixing valve is superior to the temperature change of the hot water from the intermediate mixing valve. By controlling in relation to the response speed of the valve, the overshoot or undershoot of the hot water temperature has been greatly reduced, and the conventional problems have been solved.

  In other words, in this control method, in the region where the flow rate used by the curan or the like is high, the mixing balance of the high-temperature water and the intermediate-temperature water of the intermediate mixing valve is not easily affected by the flow rate fluctuation of the curan or the like. It is possible to suppress and control well. For example, when hot water is used at a flow rate of 10L with a curan, if the curan is squeezed and changed to a flow rate of 7L, this flow rate change is transmitted as a pressure fluctuation to the hot water storage tank side, which affects the mixing balance of the intermediate mixing valve. However, when the flow rate of the intermediate mixing valve is high, the degree of influence is small, and the phenomenon that the mixing balance is not greatly lost does not occur, and the response speed of the intermediate mixing valve <the response speed of the hot water mixing valve By controlling it, it is possible to stably secure the prescribed mixed hot water temperature.

  However, when the above control method is in a region where the flow rate used by the curan is low, the mixing balance of the high temperature water and the intermediate temperature water of the intermediate mixing valve is greatly affected by the flow rate fluctuation of the curan etc. Hot water temperature fluctuates. When the mixed hot water temperature of the intermediate mixing valve fluctuates, the hot water supply mixing valve adjusts the mixing balance of the mixed water and the water supplied from the water supply pipe so as to absorb this fluctuation so as to reach the set temperature. When the water side opening degree is adjusted by the control of the hot water supply mixing valve, the water supply pressure fluctuates and is transmitted as pressure fluctuation to the hot water storage tank side, which affects the mixing balance of the intermediate mixing valve. The influence of the pressure fluctuation on the mixing balance of the intermediate mixing valve is large when the flow rate is small, and the response speed of the intermediate mixing valve is set to be slow, so that it takes time to correct the mixing balance. As a result, the mixed water from the intermediate mixing valve fluctuates, and this fluctuation is amplified by the hot water supply mixing valve that responds at high speed, and the fluctuation range further increases. By repeating this, since the intermediate mixing valve and the hot water supply mixing valve continue to fluctuate without converging to a stable region, there is a problem that a predetermined mixed hot water temperature cannot be stably supplied. For example, when hot water is used at a flow rate of 10L with a curan, if the currant is squeezed and changed to a flow rate of 2L, the hot water storage tank compared to the flow rate fluctuation in the high flow rate region due to the flow rate variation to the low flow rate region. This is transmitted as a large pressure fluctuation to the side and greatly affects the mixing balance of the intermediate mixing valve. Furthermore, since the flow rate is as small as 2 L, if the mixing balance is broken even a little, it appears as a large hot water temperature fluctuation. Therefore, the intermediate mixing valve is controlled in order to correct this variation, but the control is performed in the relationship of the response speed of the intermediate mixing valve <the response speed of the hot water mixing valve. The phenomenon of repeated fluctuations occurred with the valve, and stable hot water supply was not possible.

  Furthermore, the above problem is more likely to occur as the target hot water temperature of the intermediate mixing valve is closer to the set temperature, and it is difficult to set the target temperature of the intermediate mixing valve as low as possible for the purpose of preferentially using medium-temperature water. there were.

  In addition, in the case of the above-mentioned Patent Document 2, even when curan hot water and bath pouring are used simultaneously as loads, the response speed relationship with the intermediate mixing valve is controlled to be constant, and the response is considered in consideration of simultaneous use. When conditions such as speed were set, the above-described problems were encountered in single use.

  The present invention solves the above-described conventional problems, and by selectively using a control mode for single use and simultaneous use, a predetermined hot water temperature can be stably supplied regardless of the use flow range, and an intermediate mixing valve can be used. The target hot water temperature is set as low as possible to provide a hot water mixing control method capable of preferentially using medium hot water, thereby improving usability and COP.

In order to solve the above-described conventional problems, a hot water storage type hot water supply apparatus of the present invention includes a tapping pipe for taking out hot water at an upper part of a tank, an intermediate temperature hot water pipe for taking out hot water at a substantially middle part of the tank, the tapping pipe and the intermediate temperature hot water. A first mixing valve that mixes hot water from a pipe, a plurality of usage-side mixing valves that mix hot water from the first mixing valve and water from a water supply pipe and supply hot water at a predetermined temperature to different terminal sides, respectively. A control unit that performs valve opening control of the first mixing valve and the plurality of usage-side mixing valves, and the control unit sets the first mixing valve and the plurality of usage-side mixing valves at a predetermined valve opening / closing speed. A first mixing control mode for performing mixing control, and a second mixing control mode for performing mixing control by reversing the relationship between the valve opening and closing speeds of the first mixing valve and the plurality of usage-side mixing valves in the first mixing control mode. And one of the plurality of use side mixing valves is used alone The first mixing control mode and the second mixing control mode are switched under a predetermined condition, and when the plurality of use mixing mixing valves are used simultaneously, control is performed only in the first mixing control mode. It is a thing.

  According to the above invention, the control mode is selectively used depending on whether a plurality of use side mixing valves are used alone or simultaneously. Since the valve opening / closing speed of the side mixing valve is switched under a predetermined condition, when the mixing condition of the first mixing valve is lost and the hot water temperature may change, the first mixing valve Switching to a valve opening / closing speed that can quickly correct the disruption of the mixing balance, and the first mixing valve preferentially controls the mixing, thereby stabilizing the hot water temperature of the mixed water from the first mixing valve and mixing on the use side By switching the valve opening / closing speed to a setting slower than the valve opening / closing speed of the first mixing valve, the fluctuation of the feed water pressure is reduced, the transmission of the pressure fluctuation to the hot water storage tank is suppressed, and the mixing balance of the first mixing valve is reduced. The influence can be reduced. Thereby, the amplification effect | action of the hot water temperature fluctuation between a 1st mixing valve and a utilization side mixing valve can be prevented, and the stable hot water temperature with a small fluctuation range can be ensured.

  Further, under the condition that the mixing balance of the first mixing valve is not disturbed, the use-side mixing valve is set to a valve opening / closing speed that preferentially performs the mixing control, and the valve opening / closing speed of the first mixing valve is set to the use-side mixing valve. By setting a slower setting, it is possible to accurately control the set temperature.

  Further, under the condition that the first mixing valve preferentially performs the mixing control, it is possible to set the target hot water temperature from the first mixing valve as close as possible to the set temperature. The hot water can be secured below the hot water tank, and the use of the hot water above the hot water tank can be kept to a minimum. Can be achieved.

  And when using it simultaneously, since control is not performed, but it controls by the relationship of the valve opening / closing speed defined beforehand, the stable hot water temperature can be supplied to a some user side terminal.

  The hot water storage type hot water supply apparatus of the present invention can stably supply a predetermined hot water temperature regardless of use conditions by actively using the control mode in the single use and the simultaneous use, and actively supplies the medium hot water. It can be taken out, low-temperature water can be secured below the hot water tank, and the use of high-temperature water above the hot water tank can be kept to a minimum. Can be achieved.

1st invention is the hot water storage type hot water supply apparatus which stores the hot water heated using the heat pump circuit in the stratified state from the tank upper part, and supplies desired hot water to the terminal side using the hot water, Comprising: A hot-water pipe for taking out hot water, a medium-temperature hot-water hot-water pipe for taking out hot water in a substantially intermediate portion of the tank, a first mixing valve for mixing hot water from the hot-water pipe and the intermediate-temperature hot water pipe, and hot water and water supply from the first mixing valve A plurality of usage-side mixing valves that mix water from the pipes and supply hot water of a predetermined temperature to different terminals, respectively, and a controller that controls the opening of the first mixing valve and the plurality of usage-side mixing valves The control unit includes: a first mixing control mode for performing mixing control on the first mixing valve and the plurality of usage-side mixing valves at a predetermined valve opening / closing speed; and a first mixing valve in the first mixing control mode; The relationship between the valve opening and closing speeds of multiple user-side mixing valves In the case of having a second mixing control mode for performing mixing control by rotating and using one of the plurality of usage-side mixing valves alone, the first mixing control mode and the second mixing control mode are set to predetermined conditions. When the plurality of used mixing and mixing valves are used at the same time, control is performed only in the first mixing control mode.

  In addition, the control mode is selectively used depending on whether a plurality of use side mixing valves are used independently or simultaneously. When used independently, the first mixing valve and the use side mixing valve Since the valve opening / closing speed is switched under a predetermined condition, the mixing balance of the first mixing valve is lost when the mixing balance of the first mixing valve is lost and there is a risk of fluctuations in hot water temperature. Is switched to a valve opening / closing speed that can be quickly corrected, and the first mixing valve preferentially controls the mixing, thereby stabilizing the hot water temperature of the mixed water from the first mixing valve and opening / closing the use-side mixing valve By switching the speed to a setting slower than the valve opening / closing speed of the first mixing valve, the fluctuation of the feed water pressure is reduced, the transmission of the pressure fluctuation to the hot water storage tank is suppressed, and the influence on the mixing balance of the first mixing valve is reduced. be able to. Thereby, the amplification effect | action of the hot water temperature fluctuation between a 1st mixing valve and a utilization side mixing valve can be prevented, and the stable hot water temperature with a small fluctuation range can be ensured.

  Further, under the condition that the mixing balance of the first mixing valve is not disturbed, the use-side mixing valve is set to a valve opening / closing speed that preferentially performs the mixing control, and the valve opening / closing speed of the first mixing valve is set to the use-side mixing valve. By setting a slower setting, it is possible to accurately control the set temperature.

  Further, under the condition that the first mixing valve preferentially performs the mixing control, it is possible to set the target hot water temperature from the first mixing valve as close as possible to the set temperature. The hot water can be secured below the hot water tank, and the use of the hot water above the hot water tank can be kept to a minimum. Can be achieved.

  And when using it simultaneously, since control is not performed, but it controls by the relationship of the valve opening / closing speed defined beforehand, the stable hot water temperature can be supplied to a some user side terminal.

  The second invention sets the valve opening / closing speed of the first mixing valve slower than the valve opening / closing speed of the use-side mixing valve as the first mixing control mode, and uses the valve opening / closing speed of the first mixing valve as the second mixing control mode. It is characterized by being set faster than the valve opening / closing speed of the side mixing valve.

  Under the condition that the mixing balance of the first mixing valve is not lost, the valve opening / closing speed of the first mixing valve is set slower than the valve opening / closing speed of the user-side mixing valve, and the user-side mixing valve preferentially performs the mixing control. By setting the first mixing control mode to be performed, it is possible to accurately control the set temperature. In addition, when the mixing balance of the first mixing valve is lost and there is a risk of fluctuations in the hot water temperature, the valve opening / closing speed of the first mixing valve is set faster than the valve opening / closing speed of the user-side mixing valve. By setting the second mixing control mode in which the first mixing valve preferentially performs mixing control, the mixing balance of the first mixing valve is quickly corrected and the hot water temperature of the mixed water from the first mixing valve is stabilized. By switching the valve opening / closing speed of the use-side mixing valve to a setting slower than the valve opening / closing speed of the first mixing valve, the fluctuation of the feed water pressure is reduced, the transmission of the pressure fluctuation to the hot water storage tank is suppressed, and the first The influence on the mixing balance of the mixing valve can be reduced, the amplification effect of the hot water temperature fluctuation between the first mixing valve and the use side mixing valve can be prevented, and a stable hot water temperature with a small fluctuation width can be secured. it can.

According to a third aspect of the present invention, when switching from the first mixing control mode to the second mixing control mode is using one of a plurality of usage side mixing valves alone, the first mixing valve and the usage side mixing This is performed when the deviation between the outlet temperature of the valve and the target temperature is within a predetermined value and continues for a predetermined time.

  As a condition that the mixing balance of the first mixing valve may be lost and the hot water temperature fluctuation may occur during single use, the outlet temperature of the first mixing valve approaches the target temperature and the first mixing valve is within the mixing control range. When the use side mixing valve approaches the set temperature, which is the target temperature, the use side mixing valve enters the mixing control range, and the state continues for a predetermined time, the first mixing valve preferentially performs the mixing control. Since switching to the second mixing control mode is performed, it is possible to switch to the optimal mixing control mode before the hot water temperature fluctuation occurs, and to ensure a stable hot water temperature with a small fluctuation range.

  According to a fourth aspect of the present invention, the valve opening / closing speeds of the first mixing valve and the plurality of use side mixing valves in the first mixing control mode are changed according to the deviation between the outlet temperature of each mixing valve and the target temperature. It is characterized by.

  And the control precision with respect to target temperature can be raised by setting valve opening / closing speed late | slow as outlet temperature of a 1st mixing valve and several utilization side mixing valve approaches target temperature.

  In a fifth aspect of the invention, the valve opening / closing speed of the first mixing valve in the second mixing control mode is changed according to the deviation between the outlet temperature and the target temperature, and the valve opening / closing speed of the use-side mixing valve is changed between the outlet temperature and the target temperature. It is characterized by a fixed value at a low speed regardless of the deviation.

  In the second mixing control mode in which the first mixing valve preferentially performs mixing control, the valve opening / closing speed of the use side mixing valve is set to a low fixed value, and the valve opening / closing speed of the first mixing valve is set to the value of the use side mixing valve. It is faster than the valve opening / closing speed, and the valve opening / closing speed is gradually slowed as the outlet temperature approaches the target temperature.This increases the control accuracy for the target temperature and prevents the intermediate mixing valve and load-side mixing valve from interfering with each other. This ensures a stable hot water temperature with little fluctuation.

  A sixth invention is a hot water storage type hot water supply apparatus that stores hot water heated using a heat pump circuit in a stratified state from the upper part of the tank and supplies the desired hot water to a plurality of terminals using the hot water. A tapping pipe for taking out hot water, a medium temperature tapping pipe for taking out hot water at a substantially intermediate part of the tank, a first mixing valve for mixing hot water from the tapping pipe and the middle temperature tapping pipe, and mixing from the first mixing valve A first temperature detector for detecting the temperature of hot water, a hot water mixing valve for mixing hot water from the first mixing valve and water from a water supply pipe and supplying hot water at a predetermined temperature to a hot water supply terminal, and the hot water mixing valve A hot water temperature detector for detecting the temperature of the mixed hot water, a bath mixing valve for mixing hot water from the first mixing valve and water from the water supply pipe and supplying hot water at a predetermined temperature to the bath terminal, and the bath mixing valve Bath temperature to detect the temperature of mixed hot water from A detector, temperature setting means for setting the temperature of hot water supplied to the hot water supply terminal and bath terminal, and the first mixing valve, the hot water supply mixing valve, and the bath mixing valve are adjusted to control the hot water at a set temperature. And a control unit that, when one of the hot-water supply mixing valve or the bath mixing valve is operating independently, the deviation between the detected temperature of the first temperature detector and the set temperature is a predetermined value. In the following, and when the deviation between the detected temperature of the hot water supply temperature detector or the bath temperature detector and the set temperature is within a predetermined range, the valve opening / closing speed of the first mixing valve is determined in advance according to the deviation between the target temperature and the hot water temperature. Set based on the set high-speed pattern and perform mixing control at a preset fixed value of the hot water mixing valve or bath mixing valve, and the hot water mixing valve and bath mixing valve operate simultaneously. When the first The valve opening / closing speed of the joint valve is set based on a low-speed pattern set in advance according to the deviation between the target temperature and the tapping temperature, and the valve opening / closing speed of the hot water mixing valve or bath mixing valve is set in advance according to the deviation between the target temperature and the tapping temperature. The mixing control is performed based on the set high-speed pattern.

The load-side mixing valve is composed of a hot water mixing valve and a bath mixing valve, and the valve opening / closing speeds of the first mixing valve and the hot water mixing valve or the bath mixing valve are set to a low-speed pattern and a high-speed respectively according to the deviation between the target temperature and the hot water temperature. Set as a pattern, and when using a hot water mixing valve or a bath mixing valve alone, select and use a low speed pattern and a high speed pattern according to the specified conditions. The specified hot water temperature can be supplied stably and medium hot water can be actively taken out. Low temperature water can be secured below the hot water tank, and hot water above the hot water tank can be used. Can be kept to a minimum, the high COP boiling operation and the suppression of hot water can be suppressed, and the hot water mixing valve and bath mixing valve are used simultaneously. In this case, the control mode for selecting the low-speed pattern and the high-speed pattern is not switched, and the control is performed according to a predetermined valve opening / closing speed, so that a stable hot water temperature is supplied to a plurality of user terminals. Can do.

  The seventh invention is characterized in that the valve opening / closing speed based on the high-speed pattern during simultaneous operation of the hot water mixing valve and the bath mixing valve is set so that the hot water mixing valve is faster than the bath mixing valve. Is.

  And, when the use of currant and bath pouring are performed at the same time, the valve opening / closing speed of the hot water mixing valve is made faster than the bath mixing valve in order to prioritize hot water temperature control on the curran side, and supplied from the first mixing valve By responding quickly to fluctuations in the hot water from the bath side, stable hot water supply with little fluctuation from the currant side can be achieved.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a configuration diagram of a hot water storage type hot water supply apparatus according to a first embodiment of the present invention.

  The hot water storage tank 101 is provided with a boiling pipe 102 in which a lower part and an upper part are communicated with each other, and a boiling pump 103 and a heat exchanger 104 are provided in the middle thereof. The water in the lower part of the hot water storage tank 101 is guided to the heat exchanger 104 by the boiling pump 103 through this boiling path, and heated in the process of passing through the heat exchanger 104 to become hot water, and is guided to the upper part of the hot water storage tank 101. The hot water supplied to the hot water storage tank 101 is accumulated in layers in the hot water storage tank 101 in such a manner that the hot water is separated into the upper part and the water is separated into the lower part due to the difference in specific gravity. When the hot water in the hot water storage tank 101 is used, water is supplied from the water supply pipe 105 into the hot water storage tank 101, and the hot water reduced in accordance with the use state is placed in the hot water storage tank 101 at the upper part. The water supplied from 105 is stored in a separated state at the bottom.

  The heat pump circuit 106 serving as a heat source for the heat exchanger 104 is composed of a compressor 107, an expansion valve 108, and a forced air-cooled evaporator 110 using a fan 109. Carbon dioxide is used as a refrigerant, and a critical pressure is set on the high-pressure side. It is possible to store hot water close to 90 ° C. by operating in a temperature exceeding that, and hot water storing about 65 ° C. considering Legionella bacteria can be performed at a high COP.

  Next, a use side circuit configuration for supplying hot water in the hot water storage tank 101 to the load side will be described. A hot water discharge pipe 111 for taking out high temperature water is provided at the upper part of the hot water storage tank 101, and the hot water discharge pipe 111 and the water supply pipe 105 are provided. An intermediate hot water discharge pipe 112 for taking out the medium-temperature water is provided at a substantially intermediate portion.

A bath utilization circuit 116 connected to a lower part of the hot water storage tank 101 through a circulation pump 115 is provided from the hot water outlet pipe 111 to a bath heat exchanger 114 for exchanging heat with hot water in the bathtub 113 and performing a reheating operation. On the secondary side of the bath heat exchanger 114, a bath circulation circuit 119 is connected to the bath adapter 117 of the bathtub 113 and the bath pump 118 circulates the bath water. With the above configuration, the hot water supplied from the upper part of the hot water storage tank 101 is heat-exchanged with the bath water flowing through the bath circulation circuit 119 by the bath heat exchanger 114 and the temperature is lowered, and then returned to the hot water storage tank 101 as intermediate hot water. . If this bath chasing operation continues, the amount of high-temperature water in the upper part of the hot water storage tank 101 decreases and the amount of medium-temperature water accumulated below it increases. This increase phenomenon of intermediate temperature water causes various adverse effects, and is largely related to a decrease in the operating efficiency (COP) of the heat pump circuit 106 during the boiling operation. That is, when the medium temperature water is increased in the lower part of the hot water storage tank 101, heat exchange with the refrigerant of the heat pump circuit 106 is performed in a state where the incoming water temperature of the heat exchanger 104 at the time of boiling is high, and the temperature difference between the refrigerant and the hot water decreases. Heating capacity is reduced. In particular, in a heat pump cycle using carbon dioxide as a refrigerant, since the high-pressure side pressure of the heat pump is high, the degree of decrease in the operating efficiency (COP) of the heat pump becomes significant when the incoming water temperature increases.

  Further, the increase in the medium-temperature water means that the high-temperature water in the upper part of the hot water storage tank 101 is reduced, and the hot water storage capacity is lowered as a whole, leading to a shortage of hot water.

  Therefore, in the present embodiment, as a countermeasure against the warm water, an intermediate hot water pipe 112 is provided at a substantially intermediate portion of the hot water storage tank 101, and hot water supplied from the intermediate hot water pipe 112 and the upper hot water pipe 111 is mixed to obtain a predetermined mixed water. The first mixing valve 120 is provided to obtain the desired temperature, and the valve opening is adjusted by feeding back the hot water temperature detected by the first temperature detector 121 to ensure a predetermined target temperature. By providing the first mixing valve 120, it is possible to preferentially take out the hot water according to the purpose of use, and the hot water in the hot water storage tank 101 can be reduced.

  On the output side of the first mixing valve 120, a load-side circuit corresponding to the application is configured. First, as hot water use, the mixed water from the first mixing valve 120 and the water from the water supply pipe 105 are mixed to set the set temperature. A hot water supply mixing valve 122 which is one of the load side mixing valves for obtaining hot water is provided and supplied to the currant 124. A hot water temperature detector 123 is attached to the output side of the hot water mixing valve 122, and the valve opening is adjusted by feeding back the hot water temperature detected by the hot water temperature detector 123 so as to ensure a set temperature. Yes.

  For bath use, a bath mixing valve 125 is provided as one of the load side mixing valves for mixing the mixed water from the first mixing valve 120 and the water from the water supply pipe 105 to obtain hot water at a set temperature. The bath 113 is connected to the bath circulation circuit 119 via the pouring valve 126 to fill the bathtub 113 with hot water. A bath temperature detector 127 is attached to the output side of the bath mixing valve 125. By adjusting the valve opening by feeding back the hot water temperature detected by the bath temperature detector 127, the set temperature is secured. Yes.

  Note that a check valve 128 is provided in the high temperature water side supply path of the first mixing valve 120 so as to prevent the back flow of the medium temperature water from the intermediate tapping pipe 112. In addition, check valves 129 and 130 are provided in the hot water supply path of the hot water supply mixing valve 122 and the bath mixing valve 125, and a check valve 131 is provided on the output side of the hot water supply mixing valve 122.

  A hot water remote controller 132 having a switch for setting a hot water supply temperature is provided in the vicinity of the currant 124, and the bathroom has a switch for instructing the bath temperature, the amount of hot water, and the hot water hot water. A remote control 133 is provided. The operation instruction from the hot water remote controller 132 or the bath remote controller 133 is sent wirelessly or by wire to a control unit 134 provided on the apparatus body side, and various operations are performed based on the control operations previously defined by the control unit 134 according to the transmitted conditions. I try to do it.

  The hot water storage type hot water supply apparatus in the present embodiment is configured to boil the entire amount of the hot water storage tank 101 in accordance with a heating mode preset in a midnight power time zone (for example, from 23:00 to 7:00) by a boiling circuit 102 as shown in FIG. The amount of remaining hot water decreases and the amount of hot water decreases based on the temperature detected by the remaining hot water temperature detectors 135, 136, and 137 attached to the wall surface of the hot water storage tank 101 during the daytime period (7 to 23:00). When it seems that a shortage occurs, an additional boiling operation is performed to secure a necessary amount of hot water in the upper part of the hot water storage tank 101. By the above boiling operation, the hot water storage tank 101 accumulates in layers in the order of high temperature water, medium temperature water, and low temperature water from the top.

  The stored hot water is supplied from the hot water remote controller 132 or the bath remote controller 133 so that the control unit 134 controls the load side mixing valve of the usage side circuit to supply desired hot water to the usage side terminal. Yes.

  In the hot water storage type hot water supply apparatus configured as described above, the operation of the use side circuit in the present embodiment will be described. First, when hot water is used alone from the hot water side terminal Karan 124, the hot water supply remote controller 132 is used. When a desired hot water supply temperature is set and the currant 124 is opened, water supply is started from the water supply pipe 105 to the hot water storage tank 101, and the hot water and intermediate temperature water in the hot water storage tank 101 are discharged from the hot water supply pipe 111 and the intermediate hot water by the supply water pressure. It is discharged from the pipe 112 and supplied to the hot water side a and the water side b of the first mixing valve 120. At this time, if the water side b is kept fully open as an initial setting of the first mixing valve 120, the medium temperature water in the hot water storage tank 101 is discharged preferentially and supplied to the next stage from the mixing outlet side c. When this hot water temperature is detected by the first temperature detector 121 and the detected hot water temperature is higher than the temperature set by the hot water remote controller 132 by a predetermined temperature (for example, 2 ° C.), the valve opening / closing speed of the first mixing valve 120 As shown in (Table 1), the valve openings on the hot water side and the water side are adjusted so as to reach the target temperature based on a low speed pattern determined in advance in relation to the target temperature and the detected temperature.

In the above case, as shown in FIG. 3, in the hot water storage form in which substantially hot water is stored up to the intermediate tap pipe 112, the water side b is substantially fully open, so that the detected temperature may be adjusted to the target temperature. The valve opening cannot be adjusted further to the water side. For example, as the initial setting, the hot water side and the water side are stopped at a predetermined opening degree. In this state, the currant 124 is opened. If the detected temperature at that time is 48 ° C. and the set temperature is 40 ° C., the difference is 8 ° C., which is larger than the reference temperature difference of 2 ° C., so the first mixing valve 120 opens the water side opening. Control is made so that the outlet temperature on the output side c matches the target temperature by increasing the amount of medium temperature water. The valve opening / closing speed of the first mixing valve 120 at this time is set based on the low speed pattern (Table 1) because the difference between the detected temperature and the set temperature is larger than the predetermined temperature. To explain based on (Table 1), the water side is controlled to open at a speed of 30 pps until the difference between the target temperature and the detected temperature is less than 4 ° C., and the speed is switched to 15 pps when the temperature difference is less than 4 ° C. When the temperature is less than 2 ° C., the valve opening degree is controlled by switching to a speed of 5 pps. If the temperature difference is large even in the low speed pattern, it is set to be fast, and if the temperature difference becomes small, it is set to be slow. Yes. Note that the target temperature at this time is set to a temperature that is a predetermined temperature higher than the set temperature of the hot water supply remote controller 132. In the above case, the target temperature is set to 41 ° C. with respect to the set temperature of 40 ° C. It is desirable that the target temperature is set as low as possible as close to the set temperature as possible, because the contribution of the medium-temperature water can be increased, so that the medium-temperature water can be used preferentially.

  Thus, in a region where the difference between the outlet temperature of the first mixing valve 120 and the set temperature is large, the mixing control of the first mixing valve 120 is performed using a low speed pattern in which the valve opening / closing speed is set to be slow.

  The hot water mixing valve 122, which is a load-side mixing valve for adjusting hot water slightly higher than the set temperature secured by the first mixing valve 120 to the hot water temperature set by the hot water remote controller 132, is detected by the hot water temperature detector 123. Is fed back to the control unit 134 to adjust the hot water side opening and the water side opening so as to reach the set temperature. The valve opening / closing speed at this time is set based on a high-speed pattern determined in advance in relation to the set temperature and the detected temperature as shown in (Table 2).

  The valve opening / closing speed based on the high-speed pattern is changed in gain according to the hot water flow rate of the currant 124 as shown in (Table 3). For example, when the hot water flow rate is high, the valve opening / closing speed determined by the relationship between the set temperature and the detected temperature is set to a high gain, and when the hot water flow rate is medium, the medium gain is determined by the relationship between the set temperature and the detected temperature. The valve opening / closing speed is set slower than the high gain, and when the hot water flow rate is small, the valve opening / closing speed determined by the relationship between the set temperature and the detected temperature is set slower than the medium gain as a low gain.

  By changing the valve opening / closing speed pattern in the high-speed pattern according to the difference in the hot water supply flow rate, the response of the hot water supply mixing valve 122 is optimized and the interference with the first mixing valve 120 is prevented.

The specific operation will be described using (Table 2). When mixed water is supplied from the first mixing valve 120 to the hot water side d of the hot water supply mixing valve 122, the hot water side opening degree and the water side opening degree at that time are changed. Under the circumstances, mixed water having a temperature at the output side f is mixed with water supplied from the water side e and discharged. When the hot water temperature detector 123 detects this hot water temperature and the mixed hot water temperature is low, the hot water side d is closed and the hot water side d is opened. When the hot water supply flow rate is high and a high gain is selected, the valve opening / closing speed at this time is set based on a pattern set in accordance with the relationship between the set temperature of the high gain and the detected temperature. For example, the temperature difference is 10 ° C. In some cases, the valve opening is controlled at a high speed of 100 pps, and when the temperature difference becomes less than 4 ° C, the speed is switched to 50 pps. When the temperature difference further approaches the set temperature and becomes less than 2 ° C, it is switched to 18 pps. The valve opening is controlled so that the set temperature is the target. At this time, the valve opening / closing speed of the hot water mixing valve 122 is made faster than the valve opening / closing speed of the first mixing valve 120 so that the hot water mixing valve 122 and the first mixing valve 120 do not interfere with each other. By increasing the valve opening / closing speed, the responsiveness and accuracy to the set temperature are ensured.

  As described above, when one of the plurality of load side mixing valves, for example, the hot water mixing valve 122 is used alone, the temperature deviation between the outlet temperature of the first mixing valve 120 and the target temperature is equal to or higher than a predetermined temperature. In some cases, mixing control is performed using a low speed pattern in which the valve opening / closing speed of the first mixing valve 120 is set slower than the valve opening / closing speed of the hot water supply mixing valve 122 which is the load side mixing valve, and the hot water supply mixing valve 122 is controlled by the first mixing valve. Mixing control is performed using a high-speed pattern set faster than the valve opening / closing speed of 120. This control mode is defined as the first control mode.

  Next, the outlet temperature of the first mixing valve 120 approaches the target temperature, the temperature difference becomes equal to or less than a predetermined temperature set in advance, the outlet temperature of the hot water supply mixing valve 122 approaches the set temperature and falls within the predetermined temperature range, If this state continues for a predetermined time, it is determined that the first mixing valve 120 has entered the control region, and the control is performed by reversing the relationship of the conventional valve opening / closing speed. It is defined as control mode.

  That is, the valve opening / closing speed of the first mixing valve 120 that has been set based on the low speed pattern is set based on the high speed pattern, and the valve opening / closing speed of the hot water mixing valve 122 is set low regardless of the hot water supply flow rate. When the first mixing valve 120 enters the control area and is susceptible to the mixing balance due to fluctuations in the feed water pressure, the first mixing valve 120 has priority for mixing control. Thus, a high-speed pattern in which the responsiveness of the valve opening / closing speed is improved is used. The pattern switching of the valve opening / closing speed of the first mixing valve 120 and the hot water supply mixing valve 122 is maintained until the hot water supply operation is stopped, and is released when the hot water supply operation is stopped.

  The above operation will be specifically described in the hot water storage form of FIG. 4. For example, if the set temperature is 40 ° C., the target temperature of the first mixing valve 120 is 41 ° C., and the intermediate hot water discharge pipe 112 is used to secure this target temperature. The medium temperature water supplied and the high temperature water supplied from the high temperature outlet pipe 111 are mixed. At this time, when the temperature of the medium temperature water is higher than the target temperature as shown in FIG. Since there is no need to mix high-temperature water, the water side is fully opened and medium-temperature water is preferentially supplied and is not affected by the mixing balance, so the hot water supply mixing valve 122 has priority and is fast relative to the set temperature. Control is performed in the first control mode corresponding to the response speed.

Here, as shown in FIG. 4, when the temperature of the intermediate temperature water decreases and falls below the set temperature, the first mixing valve 120 opens the hot water side opening by the signal from the first temperature detector 121, and the hot hot water discharge pipe. High-temperature water from 111 is taken in and mixed with medium-temperature water to control the valve opening so that the target temperature is reached (hot water flows through the path indicated by the thick line). By this control, the outlet temperature of the first mixing valve 120 gradually approaches the target temperature. Then, the difference between the outlet temperature of the first mixing valve 120 and the set temperature becomes 2 ° C. or less, and the outlet temperature of the hot water supply mixing valve 122, that is, the hot water temperature from the currant 124 is within a predetermined temperature range with respect to the set temperature. (Within ± 2 ° C.), when both the first mixing valve 120 and the hot water supply mixing valve 122 enter a control region in which fine adjustment is made to the target temperature or set temperature, the valve opening / closing speed of the first mixing valve 120 is reduced. It sets using the high-speed pattern shown in FIG. 3, and sets the valve opening / closing speed of the hot-water supply mixing valve 122 as a low fixed value of 5 pps, for example, irrespective of the hot-water supply flow rate. By switching from the first control mode to the second control mode, the valve opening / closing speed of the first mixing valve 120 is switched from 5 pps to 18 pps when the hot water supply flow rate is 5 L, and the first mixing valve 120 is fast. The mixing control is performed with the hot water supply mixing valve 122 at a low speed, and the interference between the hot water mixing valve 122 and the first mixing valve 120, which is a problem when the control is performed with a constant relationship as in the prior art, That is, the influence on the mixing balance of the first mixing valve 120 due to the high-speed control of the hot water mixing valve 122 can be avoided, and mixing control with suppressed hot water temperature fluctuation due to the priority control of the first mixing valve 120 becomes possible.

  The above operation has been described for the case where the hot water mixing valve 122 is used alone as the load side mixing valve. However, the same control is performed stably when the bath mixing valve 125 is used alone as the load side mixing valve. Desired hot water can be ensured, and hot water can be poured into the bathtub 113 via the bath circulation circuit 119 by opening / closing control of the pouring valve 126. Since the specific control operation is the same as in the case of using hot water supply, a brief description will be given. First, when a hot water pouring temperature, for example, 45 ° C. is set by the bath remote controller 125 and a hot water filling operation is instructed, the first mixing valve In 120, hot water and medium temperature water are mixed at a predetermined opening ratio and discharged. For example, as shown in FIG. 5, in a hot water storage configuration in which substantially high-temperature water is stored up to the vicinity of the intermediate hot water discharge pipe 112, the first temperature detector 121 is used even if the first mixing valve 120 is fully opened on the water side. Since the hot water temperature detected in step 1 exceeds the target temperature, the first mixing valve 120 is held in the water side fully open state. Further, as shown in FIG. 6, when the hot water temperature in the vicinity of the intermediate tap pipe 112 is stored in a state lower than the target temperature, the detected temperature of the first temperature detector 121 at this time is the set temperature (45 When the temperature is higher than (° C.) (for example, 60 ° C.), the first mixing valve 120 is set to a target temperature (for example, 46 ° C.) higher than the set temperature by using the low-speed pattern shown in (Table 1) above. It adjusts by increasing the opening ratio of the side b and taking in a lot of warm water.

  The bath mixing valve 125 mixes the hot water supplied from the first mixing valve 120 and the water supplied from the water supply pipe 105 and feeds back the hot water temperature detected by the bath temperature detector 127 to the control unit 134. The valve opening ratio is adjusted so that the set temperature (45 ° C.) is obtained. The valve opening / closing speed of the bath mixing valve 125 at this time is set to be slower than the valve opening / closing speed based on the high speed pattern of the hot water mixing valve 122 shown in (Table 2) above (Table 4). Based on the setting.

  As described above, in the single operation of the bath mixing valve 125, the control mode in which the valve opening / closing speed of the first mixing valve 120 is set using the low-speed pattern and the valve opening / closing speed of the bath mixing valve 125 is set using the high-speed pattern. Is defined as the first mixed control mode.

  Next, in the first mixing control mode, the detected temperature of the first temperature detector 121 becomes a predetermined temperature (for example, 2 ° C.) or less with respect to the target temperature (46 ° C.), and the detected temperature of the bath temperature detector 127 is set. When the temperature is within a predetermined temperature range (± 2 ° C) with respect to the temperature (45 ° C) and this relationship continues for a predetermined time, the control is performed by reversing the relationship between the valve opening and closing speeds of the first mixing valve 120 and the bath mixing valve 125. Switching to the second mixing control mode to be performed is performed. That is, the valve opening / closing speed of the first mixing valve 120 is set based on the high speed pattern shown in the above (Table 2), and the bath mixing valve 125 is controlled with a low fixed value.

  By properly using the first mixing control mode and the second mixing control mode, even when the bath mixing valve 125 is used alone, the same effect as that when the hot water supply mixing valve 120 is used alone can be obtained.

  Next, the operation when the hot water mixing valve 122 and the bath mixing valve 125, which are load side mixing valves, are used simultaneously will be described.

  First, when a hot water filling instruction is given to the bath while hot water is being used from the curan 124 using the hot water mixing valve 120, or when the curan 124 is opened during the bath hot water filling operation When the first mixing control mode is selected as the control mode at the time of simultaneous use, the first mixing control mode is continued as it is, and the valve opening / closing speed of the first mixing valve 120 is set (Table 1). The valve opening / closing speed of the hot water mixing valve 122 is set based on the high speed pattern shown in (Table 2), and the valve opening / closing speed of the bath mixing valve 125 is set based on the high speed pattern shown in (Table 4). To set. Then, a temperature higher by a predetermined temperature than the temperature set by hot water remote controller 132 as the target temperature of first mixing valve 120 and the higher temperature set by bath remote controller 133 is set. It should be noted that the target temperature for simultaneous use and the target temperature for single use are set differently, and the difference between the set temperature in the case of single use and the set temperature in the case of simultaneous use is small. The difference is set to be large. For example, when the set temperature is 45 ° C., the target temperature is set to 46 ° C. when used alone, and the target temperature is set to 50 ° C. when used simultaneously, so that different temperatures are set. By setting the target temperature as close as possible to the set temperature as much as possible when using alone, it is possible to increase the contribution of medium-temperature water and reduce the use of high-temperature water. By setting, interference in the vicinity of the set temperature of the first mixing valve 120 and the bath mixing valve 125 or the hot water supply mixing valve 122 when mixing control is performed only in the first mixing control mode is avoided.

  Further, the relationship between the valve opening / closing speeds of the hot water mixing valve 122 and the bath mixing valve 125 during simultaneous use is controlled by the relationship of the valve opening / closing speed of the hot water mixing valve 122> the valve opening / closing speed of the bath mixing valve 125 as described above. Therefore, priority is given to the use of hot water, where the user actually feels the temperature fluctuation.

  As described above, the hot water supply apparatus of the present invention uses the control mode separately in whether to use a plurality of use-side mixing valves individually or simultaneously. Since the opening and closing speeds of the 1 mixing valve 120 and the hot water mixing valve 122 or the bath mixing valve 125, which are the use side mixing valves, are switched under predetermined conditions, the mixing balance of the first mixing valve 120 is disrupted and fluctuations in hot water temperature occur. When the condition becomes such that the first mixing valve 120 is preferentially controlled by switching to a valve opening / closing speed that can quickly correct the disruption of the mixing balance of the first mixing valve 120, The valve opening / closing speed of the hot water supply mixing valve 122 or the bath mixing valve 125 which is the use side mixing valve is set slower than the valve opening / closing speed of the first mixing valve 120 while stabilizing the hot water temperature of the mixed water from the first mixing valve 120. By switching to mitigate variations in supply pressure, suppressing the transmission of pressure fluctuations in the hot water storage tank 101, it is possible to reduce the influence of the mixing balance of the first mixing valve 120. This prevents an amplification effect of hot water temperature fluctuation between the first mixing valve 120 and the hot water mixing valve 122 or the bath mixing valve 125 which is the use side mixing valve, and ensures a stable hot water temperature with a small fluctuation range. it can.

  In addition, under conditions where the mixing balance of the first mixing valve 120 is not likely to be lost, the hot water mixing valve 122 or the bath mixing valve 125 that is the user-side mixing valve is set to a valve opening / closing speed that preferentially performs the mixing control. By setting the valve opening / closing speed of the one mixing valve 120 to be slower than that of the use-side mixing valve, it is possible to control the set temperature with high accuracy.

  Further, under the condition that the first mixing valve 120 preferentially performs the mixing control, it is possible to set the target hot water temperature from the first mixing valve 120 as close as possible to the set temperature. The hot water can be taken out positively, low temperature water can be secured below the hot water tank 101, and the use of high temperature water above the hot water tank 101 can be minimized. It is possible to suppress the cutting phenomenon.

  And when using at the same time, the control mode is not switched, and the control is performed according to a predetermined valve opening / closing speed, so that a stable hot water temperature can be supplied to a plurality of use side terminals. It is.

  As described above, the hot water supply apparatus of the present invention uses the control mode separately for single use and simultaneous use, so that a predetermined hot water temperature can be stably supplied regardless of the flow rate range used, and the target hot water of the intermediate mixing valve can be supplied. The present invention provides a hot water mixing control method capable of preferentially using medium hot water by setting the temperature as low as possible to improve usability and efficiency, and can be applied to general mixing control in a hot water bath heater.

The block diagram of the hot water storage type hot water supply apparatus in Embodiment 1 of this invention The figure which shows the boiling operation in the hot water storage type hot water supply apparatus The figure which shows operation | movement of the 1st control mode at the time of hot water supply utilization in the hot water storage type hot water supply apparatus. The figure which shows operation | movement of the 2nd control mode at the time of hot water use in the hot water storage type hot water supply apparatus. The figure which shows operation | movement of the 1st control mode at the time of bath use in the hot water storage type hot water supply apparatus. The figure which shows operation | movement of the 2nd control mode at the time of bath use in the hot water storage type hot water supply apparatus. Configuration diagram of a conventional hot water storage hot water supply system

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 Hot water storage tank 105 Water supply pipe 106 Heat pump circuit 111 Hot water discharge pipe 112 Medium temperature hot water supply pipe 120 1st mixing valve 122 Hot water supply mixing valve (load side mixing valve)
125 Bath mixing valve (load-side mixing valve)
134 Control unit

Claims (7)

A hot water storage type hot water supply device that stores hot water heated using a heat pump circuit in a stratified state from the upper part of the tank and supplies the desired hot water to the terminal side using the hot water,
A tapping pipe for taking out hot water at the upper part of the tank, a medium temperature tapping pipe for taking out hot water at a substantially middle part of the tank, a first mixing valve for mixing hot water from the tapping pipe and the middle temperature tapping pipe, and the first mixing valve. A plurality of usage-side mixing valves that mix hot water and water from a water supply pipe and supply hot water at a predetermined temperature to different terminals, respectively, and perform valve opening control of the first mixing valve and the plurality of usage-side mixing valves A control unit,
The control unit includes: a first mixing control mode for performing mixing control on the first mixing valve and the plurality of usage-side mixing valves at a predetermined valve opening / closing speed; a first mixing valve in the first mixing control mode; Having a second mixing control mode for performing mixing control by reversing the valve opening / closing speed relationship of the use side mixing valve;
When using one of the plurality of use side mixing valves alone, the first mixing control mode and the second mixing control mode are switched under a predetermined condition,
A hot water storage type hot water supply apparatus that is controlled only in the first mixing control mode when the plurality of use side mixing valves are used simultaneously. In the first mixing control mode, the valve opening / closing speed of the first mixing valve is set slower than the valve opening / closing speeds of the plurality of usage side mixing valves, and in the second mixing control mode, the valve opening / closing speed of the first mixing valve is set to the plurality of usage sides. The hot water storage type hot water supply apparatus according to claim 1, wherein the hot water supply apparatus is set faster than a valve opening / closing speed of the mixing valve. The switching from the first mixing control mode to the second mixing control mode is performed when the outlet temperature of the first mixing valve and the use side mixing valve and the target are set when one of the plurality of use side mixing valves is used alone. The hot water storage type hot water supply apparatus according to claim 1 or 2, wherein the temperature deviation is within a predetermined value and is performed when the temperature continues for a predetermined time. The valve opening / closing speed of the first mixing valve and the plurality of usage-side mixing valves in the first mixing control mode is changed according to the deviation between the outlet temperature of each mixing valve and the target temperature. The hot water storage type hot water supply apparatus according to claim 1. The valve opening / closing speed of the first mixing valve in the second mixing control mode is changed according to the deviation between the outlet temperature and the target temperature, and the valve opening / closing speed of the use side mixing valve is related to the deviation between the outlet temperature and the target temperature. The hot water storage type hot water supply apparatus according to any one of claims 1 to 4, wherein the hot water storage apparatus has a fixed value at a low speed. A hot water storage hot water supply device that stores hot water heated using a heat pump circuit in a stratified state from the upper part of the tank and supplies the desired hot water to a plurality of terminals using the hot water.
A tapping pipe for taking out hot water at the upper part of the tank, a medium temperature tapping pipe for taking out hot water at a substantially middle part of the tank, a first mixing valve for mixing hot water from the tapping pipe and the middle temperature tapping pipe, and the first mixing valve. A first temperature detector for detecting the temperature of the mixed hot water, a hot water mixing valve for mixing hot water from the first mixing valve and water from the water supply pipe and supplying hot water at a predetermined temperature to the hot water supply terminal, and the hot water mixing A hot water supply temperature detector for detecting the temperature of the mixed hot water from the valve, a bath mixing valve for mixing hot water from the first mixing valve and water from the water supply pipe and supplying hot water at a predetermined temperature to the bath terminal, and the bath A bath temperature detector for detecting the temperature of the mixed hot water from the mixing valve, a temperature setting means for setting the hot water temperature supplied to the hot water supply terminal and the bath terminal, the first mixing valve, the hot water mixing valve, and the bath mixing valve. Control to adjust the valve opening to hot water at the set temperature. And a part,
The controller is configured such that when one of the hot water supply mixing valve or the bath mixing valve is operating independently, a deviation between a detection temperature of the first temperature detector and a set temperature is a predetermined value or less, and the hot water supply temperature When the deviation between the detected temperature of the detector or bath temperature detector and the set temperature is within a predetermined range, the valve opening / closing speed of the first mixing valve is set based on a preset high-speed pattern according to the deviation between the target temperature and the tapping temperature. In addition, the mixing control is performed at a low fixed value set in advance to the opening and closing speed of the hot water mixing valve or the bath mixing valve,
When the hot water mixing valve and the bath mixing valve are operating simultaneously, the valve opening / closing speed of the first mixing valve is set based on a low speed pattern set in advance according to the deviation between the target temperature and the hot water temperature, and the hot water mixing A hot water storage type hot water supply apparatus that performs mixing control by setting a valve opening / closing speed of a valve or a bath mixing valve based on a high-speed pattern set in advance according to a deviation between a target temperature and a tapping temperature. The hot water storage type hot water supply apparatus according to claim 6, wherein the valve opening / closing speed based on the high-speed pattern during simultaneous operation of the hot water mixing valve and the bath mixing valve is set to be faster for the hot water mixing valve than for the bath mixing valve.