JP4725202B2 - Hot water storage water heater - Google Patents

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 medium-temperature water is stored, the heating operation of the heat pump cycle is performed in a state where the incoming water temperature to 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.

One example of the control method is disclosed in Patent Document 2. As shown in FIG. 4, the control method disclosed in Patent Document 2 uses the hot water from the upper part of the hot water storage tank 2, the hot water from the intermediate part of the hot water storage tank 2, and the 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, when the currant is squeezed and changed to a flow rate of 2L, the hot water storage tank is compared with the flow rate fluctuation in the high flow rate region due to the flow rate variation to the low flow 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, when using hot water mixed with an intermediate mixing valve for currant hot water supply or bath hot water filling having different operating temperatures, various problems occur depending on the usage. For example, when hot water filling is instructed when hot water is supplied and the hot water temperature is higher than the hot water temperature, the intermediate mixing valve supplies hot water at a predetermined temperature higher than the hot water temperature. In order to control, the hot water side of the hot water mixing valve that supplies hot water to the curan is supplied with hot water at a temperature higher than the hot water temperature that has been supplied up to now. There arises a problem that hot water having a higher temperature is discharged.

  In addition, this problem occurs even when the hot water temperature is not so high and about the same as the hot water temperature, and when a hot water hot water instruction is given while hot water is supplied, In consideration of safety, the water side of the hot water mixing valve is temporarily reduced as the bath mixing valve starts to operate, and the hot water side until now. Since the amount of medium-temperature water in the street is supplied, hot water with a temperature higher than the hot water supply set temperature is discharged from the curan for a short period when the decrease in the water-side water supply is recovered. When the bath hot water filling operation is started during use, a so-called overshoot phenomenon in which the temperature of the hot water from the currant rises temporarily occurs, and the overshoot increases as the hot water temperature rises. It was.

  The present invention solves the above-described conventional problem, suppresses a transient overshoot phenomenon at the start of simultaneous use of a plurality of usage-side mixing valves, and stabilizes a predetermined hot water temperature regardless of the use flow range. In addition to supplying, a hot water mixing control method capable of preferentially using medium hot water by setting the target hot water temperature of the intermediate mixing valve as low as possible is provided to improve 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 for mixing hot water from a pipe, a plurality of use side mixing valves 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 different terminal sides, and A control unit configured to control a valve opening degree of the first mixing valve and the plurality of usage-side mixing valves, and the control unit is configured to control an outlet temperature of the first mixing valve and a set temperature of the predetermined usage-side mixing valve. When the difference is within a predetermined temperature, when the other usage-side mixing valve starts operating while the predetermined usage-side mixing valve is operating among the plurality of usage-side mixing valves, the opening of the predetermined usage-side mixing valve The ratio is corrected so as to open to the water side by a predetermined opening degree.

  According to the above invention, the hot water filling valve is instructed when the hot water mixing valve is operated by using the hot water mixing valve among the plurality of use side mixing valves and the bath mixing valve. When the operation of the mixing valve is started, the opening ratio of the hot water supply mixing valve is forcibly corrected in a direction to open a predetermined opening to the water side. Even when the temperature rises, the hot water mixing valve has a larger opening on the water side than before, so the temperature of the hot water from the hot water mixing valve does not cause an overshoot, and the bath mixing valve starts operating. By reducing the amount of water supplied from the water supply pipe, the water supply amount as before can be secured by opening the water side opening much, and the overshoot phenomenon of the tapping temperature from the hot water mixing valve can be prevented. Is. In this way, by performing so-called feed-forward control that predicts in advance and corrects a predetermined amount of transient hot water temperature when a plurality of usage-side mixing valves are used simultaneously from a single use to a plurality of simultaneous uses, It is possible to suppress a transitional fluctuation when the form changes and to stably supply hot water to the load side.

  The hot water storage type hot water supply apparatus of the present invention can suppress a transient overshoot phenomenon at the start of simultaneous use of a plurality of use side mixing valves, and can stably supply a predetermined hot water temperature regardless of use conditions. It is possible to actively take out the medium temperature water, secure low temperature water below the hot water tank, minimize the use of high temperature water above the hot water tank, and raise high COP Operation and suppression of the hot water phenomenon 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 part 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, and a control unit that performs valve opening control of the first mixing valve and the plurality of usage-side mixing valves. The control unit is configured to open an opening ratio of the predetermined usage-side mixing valve when the other usage-side mixing valve starts operating while the predetermined usage-side mixing valve is operating among the plurality of usage-side mixing valves. Was adjusted to open the water side by a predetermined opening. The one in which the features.

  And, among hot water mixing valves and bath mixing valves that are a plurality of usage side mixing valves, when hot water mixing valve is operated and currant hot water is used, bath hot water filling instruction is performed and bath mixing valve is operated Is started, the opening ratio of the hot water mixing valve is forcibly corrected in a direction to open the predetermined opening to the water side, so that the hot water temperature is high and the hot water temperature of the first mixing valve is increased. Even in this case, the hot water mixing valve has a larger opening on the water side than before, so the hot water temperature from the hot water mixing valve does not cause an overshoot. As for the decrease in the water supply amount, the water supply amount as before can be secured by opening the water side opening much, and the overshoot phenomenon of the tapping temperature from the hot water mixing valve can be prevented. In this way, by performing so-called feed-forward control that predicts in advance and corrects a predetermined amount of transient hot water temperature when a plurality of usage-side mixing valves are used simultaneously from a single use to a plurality of simultaneous uses, It is possible to suppress a transitional fluctuation when the form changes and to stably supply hot water to the load side.

Further, in the first invention, when the difference between the outlet temperature of the first mixing valve and the set temperature of the predetermined usage side mixing valve is within the predetermined temperature, the control unit starts operating the other usage side mixing valve. The opening ratio of the predetermined use side mixing valve is corrected in a direction to open the predetermined opening to the water side.

  And, among hot water mixing valves and bath mixing valves that are a plurality of usage side mixing valves, when hot water mixing valve is operated and currant hot water is used, bath hot water filling instruction is performed and bath mixing valve is operated Is started, when the outlet temperature of the first mixing valve is lower than the set temperature of the hot water mixing valve by a predetermined temperature, the opening ratio of the hot water mixing valve is forcibly corrected in a direction to open the predetermined opening to the water side. Therefore, only when there is a risk that the outlet temperature of the first mixing valve will rise more than before due to the hot water filling instruction of the bath and the temperature of the hot water supplied to the hot water side of the hot water mixing valve may rise. It is possible to prevent the overshoot phenomenon of the tapping temperature from the hot water supply mixing valve by correcting the opening of the water side in a direction to open a large amount in advance. In addition, when the outlet temperature of the first mixing valve is higher than the set temperature of the hot water supply mixing valve by a predetermined temperature and the hot water temperature of the first mixing valve does not change even when a hot water filling instruction is given, for example, hot water in a hot water storage tank When the temperature is almost filled with high-temperature water, hot water is discharged even if the first mixing valve is fully opened on the water side. In this case, the correction operation is not performed.

A second aspect of the present 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 the terminal side using the hot water. 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 part 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, and a control unit that performs valve opening control of the first mixing valve and the plurality of usage-side mixing valves. And the controller is configured to use the other use side mixing valve while the predetermined use side mixing valve is operating among the plurality of use side mixing valves when the temperature of the medium temperature water from the intermediate temperature hot water discharge pipe is equal to or lower than a predetermined temperature. When the operation starts, the predetermined use side mixing valve is opened. The ratio is characterized in that so as to correct the direction of opening by a predetermined angle in the water side.

  And, among hot water mixing valves and bath mixing valves that are a plurality of usage side mixing valves, when hot water mixing valve is operated and currant hot water is used, bath hot water filling instruction is performed and bath mixing valve is operated When the temperature of the hot water from the hot hot water pipe is lower than the set temperature of the hot water mixing valve by a predetermined temperature, the opening ratio of the hot water mixing valve is forcibly corrected in the direction to open the predetermined opening to the water side. Therefore, only when there is a risk that the outlet temperature of the first mixing valve will rise more than before due to the hot water filling instruction of the bath and the temperature of the hot water supplied to the hot water side of the hot water mixing valve may rise. By correcting the water side opening of the mixing valve in a direction to open a large amount in advance, it is possible to prevent the overshoot phenomenon of the tapping temperature from the hot water supply mixing valve. Further, when the temperature of the medium temperature water from the medium temperature hot water discharge pipe is high and the hot water filling temperature of the first mixing valve does not change even when a hot water filling instruction is given, the correction operation is not performed.

The third aspect of the invention is characterized in that when the control unit performs the correction operation of the use side mixing valve under a predetermined condition, the control unit performs the valve opening / closing speed in the fastest mode set faster than that in the normal operation. is there.

  And, among hot water mixing valves and bath mixing valves that are a plurality of usage side mixing valves, when hot water mixing valve is operated and currant hot water is used, bath hot water filling instruction is performed and bath mixing valve is operated Since the correction operation of the hot water mixing valve performed under the predetermined conditions is performed in the fastest mode set faster than the normal operation, the hot water mixing valve hot water accompanying the start of the operation of the bath mixing valve A rise in the side temperature or a decrease in the water supply amount can be quickly dealt with in advance, and an overshoot phenomenon of the tapping temperature from the hot water mixing valve can be prevented.

According to a fourth aspect of the present invention, the control unit performs mixing control of the first mixing valve and the plurality of usage-side mixing valves at a predetermined valve opening / closing speed, and the first mixing valve in the first mixing control mode. And a second mixing control mode for performing mixing control by reversing the relationship between the opening and closing speeds of the use-side mixing valve, and switching between the first mixing control mode and the second mixing control mode under a predetermined condition. It is characterized by this.

  Since the opening and closing speeds of the first mixing valve and the plurality of use-side mixing valves are switched under a predetermined condition, the mixing balance of the first mixing valve is lost, and there is a possibility that fluctuations in hot water temperature may occur. When this happens, the mixing temperature of the first mixing valve is switched to a valve opening / closing speed that can be quickly corrected, and the first mixing valve preferentially controls the mixing so that the hot water temperature of the mixed water from the first mixing valve By switching the valve opening / closing speed of the user-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 alleviated and the transmission of the pressure fluctuation to the hot water storage tank is suppressed. The influence on the mixing balance of the first mixing valve 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.

The fifth invention sets the valve opening / closing speed of the first mixing valve as 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 sixth aspect of the present invention, switching from the first mixing control mode to the second mixing control mode has continued for a predetermined time when the deviation between the outlet temperature of the first mixing valve and the use-side mixing valve and the target temperature is within a predetermined value. It is characterized by what is sometimes done.

  As a condition that the mixing balance of the first mixing valve may be lost and the hot water temperature fluctuation may occur, the outlet temperature of the first mixing valve approaches the target temperature and the first mixing valve enters the mixing control range. The second mixing control mode in which the first mixing valve preferentially performs the mixing control when the mixing valve approaches the set temperature that is the target temperature and the use side mixing valve enters the mixing control range and the state continues for a predetermined time. Therefore, it is possible to switch to the optimal mixing control mode before the hot water temperature fluctuation occurs, and to secure a stable hot water temperature with a small fluctuation range.

The seventh invention is characterized in that the valve opening / closing speeds of the first mixing valve and the use-side mixing valve 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 what.

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

In an eighth 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 ninth 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. The hot water mixing valve and bath mixing have a second mixing control mode in which mixing control is performed based on the set high speed pattern and the valve opening / closing speed of the hot water mixing valve or bath mixing valve is set at a low fixed value set in advance. Valves move simultaneously When opening and closing, 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 tapping temperature, and the valve opening / closing speed of the hot water mixing valve or bath mixing valve is set as the target. A first mixing control mode for performing mixing control by setting based on a high-speed pattern set in advance according to a deviation between the temperature and the tapping temperature, and the bath mixing valve starts operating while the hot water mixing valve is operating In this case, the hot water mixing valve has a fastest mode for correcting the water supply mixing valve in a direction to open a predetermined opening degree on the water side at a speed faster than the valve opening / closing speed set in the 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. As a pattern, by selecting and using a low-speed pattern and a high-speed pattern according to a predetermined condition, it is possible to stably supply a predetermined hot water temperature regardless of use conditions in hot water use or bath use. It is possible to actively take out the medium temperature water, secure low temperature water below the hot water tank, minimize the use of high temperature water above the hot water tank, and raise high COP Operation and suppression of the hot water phenomenon can be achieved. In addition, when the hot water mixing valve is operated and the currant hot water is used, when the hot water filling instruction is given and the operation of the bath mixing valve is started, the opening ratio of the hot water mixing valve is set to the water side. Since the correction is forcibly corrected in the direction of opening, only the hot water filling temperature is high and the hot water temperature of the first mixing valve rises, so that the hot water supply mixing valve opens more on the water side than before. Therefore, the temperature of the hot water from the hot water supply mixing valve does not cause overshoot, and the decrease in the water supply amount from the water supply pipe with the start of the operation of the bath mixing valve will increase the water side opening until now. Therefore, it is possible to secure a sufficient amount of water supply, and to prevent the overshoot phenomenon of the temperature of the hot water from the hot water supply mixing valve. In this way, it is used by performing so-called feed-forward control that predicts and corrects a predetermined amount of transient hot water temperature fluctuations when the hot water mixing valve is used simultaneously with the bath mixing valve. It is possible to suppress a transitional fluctuation when the form changes and to stably supply hot water to the load side.

  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 is provided in the vicinity of the currant 124, and a bath remote controller 133 is provided in the bathroom. 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 a desired hot water supply temperature is set by the hot water supply remote controller 132 and the currant 124 is opened, the water supply Water supply from the pipe 105 to the hot water storage tank 101 is started, and hot water and intermediate temperature water in the hot water storage tank 101 are discharged from the hot water discharge pipe 111 and the intermediate hot water discharge pipe 112 by the supply water pressure, and the hot water side a and water of the first mixing valve 120 are discharged. Supplied to side b. 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 a temperature set by the hot water supply 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 target set temperature is reached. 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 the temperature difference between the outlet temperature of the first mixing valve 120 and the target temperature is equal to or higher than a predetermined temperature set in advance, the valve opening / closing speed of the first mixing valve 120 is changed to the hot water supply mixing valve 122 which is a load side mixing valve. The mixing control is performed using a low-speed pattern set slower than the valve opening / closing speed of the water, and the hot water mixing valve 122 is controlled using a high-speed pattern set faster than the valve opening / closing speed of the first mixing valve 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.

  Although 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, the same control is performed when the bath mixing valve 125 is used alone as the load side mixing valve. By doing so, desired hot water can be secured stably, 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, the description is omitted.

  Next, a case will be described in which a hot water filling operation instruction is given in a state where the hot water supply mixing valve 122 is used alone.

  When hot water is supplied from the curan 124 based on a temperature set by the hot water remote controller 132 (for example, 40 ° C.), a hot water filling instruction is given by the bath remote controller 133, and the hot water filling temperature at that time is 48 ° C. The first mixing valve 120 controls the opening ratio by setting the control target temperature to 53 ° C., which is higher than the preset target temperature by 41 ° C. from the current target control temperature (41 ° C.), and raises the tapping temperature of the first mixing valve 120. Let If this control state is left as it is, the hot water supply mixing valve 122 initially performs hot water discharge at a ratio of opening with respect to the target control temperature (41 ° C.) until now when the hot water filling instruction is given. The hot water having a temperature different from the set temperature is supplied from the currant 124 under the influence of the rise in the hot water temperature of the first mixing valve 120 in accordance with the instruction, and the influence of the large hot water temperature fluctuation that is not expected by the user. Will receive. However, as shown in FIG. 3, in the case where almost the entire amount in the hot water storage tank 101 is filled with high-temperature water as shown in FIG. 3, the hot water temperature from the first mixing valve 120 is Since it does not change, the opening ratio of the hot water supply mixing valve 122 does not change, and the hot water temperature from the currant 124 does not change.

  As shown in FIG. 4, the condition for causing the above phenomenon is that the hot water temperature in the hot water storage tank 101 in the vicinity of the intermediate hot water pipe 112 is lower than the set temperature, and the first mixing valve 120 is mixed with hot water from the hot water pipe 111. It occurs in the region controlled to the target control temperature, and this state is judged by the difference between the hot water temperature of the first mixing valve 120 and the set temperature of the hot water supply mixing valve 122, and the temperature difference is a predetermined temperature. Is within the region where the first mixing valve 120 performs control by mixing hot water from the hot water outlet pipe 111 with respect to the target control temperature, and when the control target temperature is increased by a bath hot water filling instruction, the first mixing valve 120 There is a possibility that the hot water temperature rises and hot hot water is discharged from the currant 124. Further, as a method of determining this state, when the temperature of the intermediate hot water is equal to or lower than a predetermined temperature using the signal from the remaining hot water temperature detector 136 that detects the temperature of the intermediate hot water, the first mixing valve 120 is brought into the control range. It can also be judged that there is.

  Then, when a bath hot water filling instruction is given during the Karan hot water while satisfying the above fluctuation occurrence condition, the control unit 134 sets the valve opening ratio of the hot water mixing valve 122 to the water side opening by a predetermined opening. Drive in the direction of opening. By this correction operation, the hot water supply mixing valve 122 corrects the water side opening degree in the direction of opening the water side opening in the fastest mode set at a higher speed than the normal operation at the same time when the hot water temperature of the first mixing valve 120 starts to rise due to the hot water filling instruction. Therefore, the overshoot phenomenon of the hot water supply mixing valve 122 due to the rise of the hot water temperature of the first mixing valve 120 can be prevented.

  Further, the reason why this correction operation is performed in the fastest mode is to suppress the influence caused by the decrease in the water supply flow rate in addition to the rise in the hot water temperature of the first mixing valve 120 accompanying the bath hot water filling instruction. That is, the operation of the bath mixing valve 125 during the bath hot water operation starts from the water side fully open state in consideration of safety, and when the bath water hot water operation is started while using Karan hot water, In this state, a large amount of water flows on the water side of the bath mixing valve 125 and the flow rate flowing on the water side of the hot water mixing valve 122 temporarily decreases. Due to this phenomenon, the hot water mixing valve 122 is in a direction in which the hot water balance is lost and the hot water temperature is further raised. This situation occurs transiently in a short period of time when the bath mixing valve 125 shifts to the control range, but the temperature currently used fluctuates to a high temperature side in a situation that is not anticipated by the user. Therefore, it was extremely inconvenient. Therefore, when it is judged that there is a risk of hot water temperature fluctuations during Karan hot water, the corrective action is performed quickly in the fastest mode, so that fluctuations in the hot water temperature are suppressed even if the bath hot water filling operation is started while using Karan. Is.

  As described above, the hot water supply apparatus according to the present invention operates when the hot water mixing valve 122 and the curan hot water are used among the hot water mixing valve 122 and the bath mixing valve 125, which are a plurality of use side mixing valves. When the hot water filling instruction is performed and the operation of the bath mixing valve 125 is started, the opening ratio of the hot water mixing valve 122 is forcibly corrected in a direction to open the water opening by a predetermined opening degree. Even when the tension temperature is high and the hot water temperature of the first mixing valve 120 rises, the hot water supply mixing valve 122 is more open than before, and the hot water temperature from the hot water mixing valve 122 causes overshoot. In addition, with the start of the operation of the bath mixing valve 125, a decrease in the amount of water supplied from the water supply pipe 105 can also ensure the same amount of water supply as before by opening a large amount of water side opening. Hot water temperature from valve 122 One in which it is possible to prevent an overshoot phenomenon. In this way, by performing so-called feed-forward control that predicts in advance and corrects a predetermined amount of transient hot water temperature when a plurality of usage-side mixing valves are used simultaneously from a single use to a plurality of simultaneous uses, It is possible to suppress a transitional fluctuation when the form changes and to stably supply hot water to the load side.

  In addition, since the valve opening / closing speed of the hot water mixing valve 120 or the bath mixing valve 122 which is the first mixing valve and the use side mixing valve is switched under a predetermined condition, the mixing balance of the first mixing valve 120 is disrupted and the hot water temperature fluctuates. When the condition is such that there is a risk of occurrence of a failure, the first mixing valve 120 is preferentially controlled by switching to a valve opening / closing speed of a high-speed pattern that can quickly correct the mixing balance breakdown of the first mixing valve 120. By performing the stabilization of the hot water temperature of the mixed water from the first mixing valve 120, the valve opening / closing speed of the hot water mixing valve 120 or the bath mixing valve 122 which is the use-side mixing valve is set to the valve of the first mixing valve 120. By switching to a low-speed pattern setting that is slower than the opening and closing speed, the fluctuation of the feed water pressure is alleviated, the transmission of the pressure fluctuation to the hot water storage tank 101 is suppressed, and the influence on the mixing balance of the first mixing valve 120 is reduced. Door can be. By the mixing control in the second control mode, the amplification effect of the hot water temperature fluctuation between the first mixing valve 120 and the hot water mixing valve 120 or the bath mixing valve 122 which is the use side mixing valve is prevented, and the fluctuation width is stable. Hot water temperature can be secured. Further, under the condition that the mixing balance of the first mixing valve is not lost, the valve opening speed of the first control mode in which the hot water mixing valve 120 or the bath mixing valve 122 which is the use side mixing valve preferentially performs the mixing control is set. By setting and setting the valve opening / closing speed of the first mixing valve 120 to be slower than the hot water supply mixing valve 120 or the bath mixing valve 122 which are the use-side mixing valves, it is possible to accurately control the set temperature.

  Furthermore, under the condition of the second control mode in which the first mixing valve 120 preferentially performs mixing control, it becomes possible to set the target hot water temperature from the first mixing valve 120 as close as possible to the set temperature. Therefore, medium-temperature water can be actively taken out, low-temperature water can be secured below the hot water storage tank 101, and use of high-temperature water above the hot water storage tank 101 can be minimized, and high COP It is possible to suppress the boiling operation and the hot water phenomenon.

  As described above, the hot water supply apparatus of the present invention can stably supply a predetermined hot water temperature regardless of the operating flow range, and can set the target hot water temperature of the intermediate mixing valve as low as possible to use the medium hot water with priority. A hot water mixing control method is provided 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 in the hot water storage type hot-water supply apparatus. The figure which shows operation | movement of the 2nd control mode in the hot water storage type hot-water supply apparatus. Configuration diagram of a conventional hot water storage hot water supply system

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 (9)

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 use-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, and perform valve opening control of the first mixing valve and the plurality of use-side mixing valves A control unit, and when the difference between the outlet temperature of the first mixing valve and the set temperature of the predetermined usage side mixing valve is within a predetermined temperature , the control unit is configured to select a predetermined one of the plurality of usage side mixing valves. When the other use side mixing valve starts operating while the use side mixing valve is in operation, the hot water storage type is configured to correct the opening ratio of the predetermined use side mixing valve in the direction to open the predetermined opening to the water side. Hot water supply device. 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 use-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, and perform valve opening control of the first mixing valve and the plurality of use-side mixing valves A control unit, and when the temperature of the intermediate temperature water from the intermediate temperature hot water pipe is equal to or lower than a predetermined temperature, the control unit is the other of the plurality of usage side mixing valves while the predetermined usage side mixing valve is operating. A hot water storage type hot-water supply apparatus that corrects the opening ratio of the predetermined use-side mixing valve in a direction to open the water side by a predetermined opening when the use-side mixing valve starts operating. The hot water storage type hot water supply apparatus according to claim 1 or 2, wherein when the control unit performs the correction operation of the use side mixing valve under a predetermined condition, the control unit performs the valve opening / closing speed in the fastest mode set faster than the normal operation. . The control unit includes a first mixing control mode for performing mixing control of the first mixing valve and the plurality of usage-side mixing valves at a predetermined valve opening / closing speed, and the first mixing valve and the usage-side mixing valve in the first mixing control mode. reversed the valve opening and closing speed of the relationship has a second mixed control mode for mixing control, claim 1-3 in which the first mixing control mode and the second mixing control mode to switch under predetermined conditions The hot water storage type hot water supply apparatus according to any one of the above. In the first mixing control mode, the valve opening / closing speed of the first mixing valve is set slower than the valve opening / closing speed of the utilization side mixing valve, and in the second mixing control mode, the opening / closing speed of the first mixing valve is set to the valve of the utilization side mixing valve. The hot water storage type hot water supply apparatus according to claim 4, wherein the hot water storage type hot water supply apparatus is set to be faster than an opening / closing speed. Switching from the first mixing control mode to the second mixing control mode is performed when the deviation between the outlet temperature of the first mixing valve and the use side mixing valve and the target temperature is in a state where a plurality of use side mixing valves are used independently. The hot water storage type hot water supply device according to claim 4 or 5, wherein the hot water storage type hot water supply device is performed when the time is within a predetermined value and continued for a predetermined time. Valve speed of the first mixing valve and the user side mixing valve in the first mixing control mode, the claim 4 which is adapted to change in accordance with the deviation of the outlet temperature and the target temperature of each mixing valve 1 The hot water storage type hot water supply apparatus according to item. 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 4 to 7 , wherein the hot water storage apparatus has a fixed value at a low speed. A hot water storage type hot water supply device that stores hot water heated by 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, and a hot water outlet pipe for taking out the hot water from the upper part of the tank Detecting the temperature of the mixed hot water from the first mixing valve, the first hot water pipe from which the hot water from the intermediate hot water pipe is taken out, the hot water from the hot hot water pipe from the intermediate hot water pipe, A temperature detector, 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 a temperature of the mixed hot water from the hot water mixing valve. A hot water temperature detector to detect, a bath mixing valve for mixing hot water from the first mixing valve and water from the water supply pipe and supplying hot water of a predetermined temperature to the bath terminal, and a temperature of the mixed hot water from the bath mixing valve Detecting bath temperature detector and before A temperature setting means for setting a hot water temperature to be supplied to the hot water supply terminal and the bath terminal, and a control unit for adjusting the valve opening of the first mixing valve, the hot water supply mixing valve, and the bath mixing valve to control the hot water at the set temperature. Prepared,
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. And having a second mixing control mode in which mixing control is performed at a low fixed value in which the valve opening / closing speed of the hot water mixing valve or bath mixing valve is preset,
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 first mixing control mode for performing 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;
Further, when the bath mixing valve starts operating while the hot water supply mixing valve is operating, the hot water supply mixing valve is opened in a direction that opens a predetermined opening to the water side at a speed faster than the valve opening / closing speed set in the high speed pattern. Hot water storage type hot water supply device with the fastest mode to correct.