JP2011226664A - Storage type hot water supply system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a storage type hot water supply system for easily and highly accurately calculating a minimum necessary tank heat storage amount for a reheating heat amount, controlling a heating means on the basis of the calculated value and suppressing the heat storage amount of a hot water storage tank.SOLUTION: The storage type hot water supply system includes: the heating means 2 for turning water from the hot water storage tank 1 to hot water at a high temperature; stored hot water temperature sensors 501a-501f for detecting the temperature of stored hot water in the hot water storage tank 1; a control circuit 100; and a reheating heat exchanger 5 for reheating the hot water in a bathtub 6 with the hot water at the high temperature from the hot water storage tank 1. The control circuit 100 predicts the reheating return temperature of the hot water returning to the hot water storage tank 1 through the reheating heat exchanger 5, calculates a reheating effective heat storage amount effective for reheating in the heat storage amount that the hot water in the hot water storage tank 1 has on the basis of the reheating return temperature and the stored hot water temperature, predicts a reheating load which is the heat amount of the hot water supplied to the bathtub 6 by reheating, and controls the heating means 2 so that the calculated reheating effective heat storage amount becomes larger than the predicted reheating load.

Description

  The present invention relates to a hot water storage hot water supply system that uses hot hot water in a hot water storage tank heated by a heating means to replenish hot water in a bathtub.

The hot water storage type hot water supply system is a system that is applied when the heating capability of the heating means is relatively small as compared with an instantaneous hot water supply system or the like, or when the rise of the capability at the time of activation of the heating means is slow.
Also, the hot water storage hot water supply system stores hot water for hot water boiled in advance by a heating means in a hot water storage tank so that the hot water does not run out due to the occurrence of a hot water supply load. It is a system that supplies hot water.
In addition, the hot water storage hot water supply system raises the temperature of hot water in the bath tub by using hot water in the hot water storage tank not only through direct discharge of hot water from the tap, but also through a memorial operation through heat exchange. This system has a function, and heat is stored in the hot water storage tank in advance by heating means so that there is no shortage of heat even for such a heat load.

  As such a conventional hot water storage type hot water supply system, for example, a hot water storage tank is proposed that performs reheating only when there is more than the amount of heat that can be reheated in the bathtub. (For example, refer to Patent Document 1).

  In addition, as such a conventional hot water storage type hot water supply system, for example, there is a system in which the heating means is heated up so that the amount corresponding to the reheating heat amount calculated by the reheating heat amount calculating means is stored in the hot water storage tank (for example, , See Patent Document 2).

Japanese Patent No. 2689028 (Claim 2, FIG. 5) Japanese Patent No. 3868908 (Claim 6, FIG. 2)

  The hot water storage hot water supply system described in Patent Document 1 is a hot water storage tank that stores hot water in a hot water storage tank only when the hot water stored in the bathtub is hot enough to replenish the hot water. Circulating into the bathtub and exchanging heat in the bathtub to reheat the hot water in the bathtub to prevent waste of heat and water and keep the hot water temperature in the bathtub constant even when bathing is repeated be able to. As a result, it is possible to avoid a situation in which the amount of heat in the hot water storage tank disappears after memorialization.

  Further, the hot water storage type hot water supply system described in Patent Document 2 is being reheated by causing the heating means to boil up so that the amount equivalent to the reheating heat amount obtained by the reheating heat amount calculation means is stored in the hot water storage tank. It is possible to reliably recharge the bath water without causing the hot water to run out.

  However, in both of Patent Documents 1 and 2 mentioned above, there is no description at all regarding a specific calculation method of the heat storage amount required for the hot water storage tank of “corresponding to the amount of reheating heat”. In many cases, the heat storage amount is controlled to be stored in the hot water storage tank, which is several times larger than the reheating heat amount. For this reason, the amount of heat stored in the hot water storage tank is maintained more than the original minimum value, and there has been a problem that energy saving has been impaired.

  The present invention has been made to solve the above-described problems, and the minimum required amount of tank heat storage for the amount of additional heat is easily calculated from the amount of additional heat, tank temperature distribution, bath temperature, and target bath temperature. The purpose of the present invention is to obtain a hot water storage hot water supply system having higher energy saving than before by controlling the heating means based on the calculated value with high accuracy and suppressing the heat storage amount of the hot water storage tank as much as possible. And

  The hot water storage type hot water supply system according to the present invention includes a heating means for heating water to make hot water, a hot water storage tank for storing hot water heated by the heating means, and a temperature of hot water in the hot water storage tank (hereinafter referred to as “hot water storage temperature”). A hot water storage temperature detecting means for detecting the hot water in the bathtub, and a control means for controlling the heating operation of the heating means; The control means includes a return return temperature prediction means for predicting a return return temperature of hot water that passes through the return heat exchanger and returns to the hot water storage tank, and a return return predicted by the return return temperature prediction means. A reheating effective heat storage amount calculating means for calculating a reheating effective heat storage amount effective for reheating out of the heat storage amounts of the hot water in the hot water storage tank based on the temperature and the hot water storage temperature detected by the hot water storage temperature detecting means; The hot water supplied to the bathtub by chasing A memorized load predicting means for predicting the memorized load that is the amount of heat, and the memorized effective heat storage amount calculated by the memorized effective heat storage amount calculating means is larger than the memorized load predicted by the memorized load predicting means. Thus, the heating operation of the heating means is controlled.

  In the present invention, predicting the return temperature of hot water returning to the hot water storage tank through the additional heat exchanger, and based on the predicted return temperature of hot water and the hot water temperature detected by the hot water temperature detecting means, Of the amount of heat stored in the hot water in the hot water storage tank, the amount of effective heat storage for reheating is calculated. Then, the reheating load that is the amount of heat of hot water supplied to the bathtub by the reheating is predicted, and the heating operation of the heating means is controlled so that the calculated effective revolving heat storage amount becomes larger than the predicted reheating load. As a result, the amount of heat stored in the hot water storage tank can be reduced as much as possible, and the system efficiency can be improved.

It is a schematic diagram which shows the structure of the hot water storage type hot water supply system which concerns on Embodiment 1 of this invention. It is a block diagram which shows the circuit structure of the hot water storage type hot-water supply system which concerns on Embodiment 1 of this invention. It is a schematic diagram which shows the calculation model of the memorial effective heat storage amount in the hot water storage type hot water supply system which concerns on Embodiment 1 of this invention. It is a schematic diagram which shows another calculation model of the memorial effective heat storage amount in the hot water storage type hot water supply system which concerns on Embodiment 1 of this invention. It is a schematic diagram which shows the prediction method of the supplementary return temperature in the hot water storage type hot-water supply system which concerns on Embodiment 1 of this invention. It is a schematic diagram which shows another calculation model of the memorial effective heat storage amount in the hot water storage type hot water supply system which concerns on Embodiment 1 of this invention. It is a schematic diagram which shows the structure of the hot water storage type hot-water supply system which concerns on Embodiment 2 of this invention. It is a block diagram which shows the circuit structure of the hot water storage type hot-water supply system which concerns on Embodiment 2 of this invention. It is a schematic diagram which shows the calculation model of the memorial effective heat storage amount in the hot water storage type hot-water supply system which concerns on Embodiment 2 of this invention. It is a figure which shows the advantage of the hot water storage type hot-water supply system which concerns on Embodiment 2 of this invention.

Embodiment 1 FIG.
FIG. 1 is a schematic diagram showing a configuration of a hot water storage type hot water supply system according to Embodiment 1 of the present invention.
The hot water storage type hot water supply system in the first embodiment includes a hot water storage tank 1 for storing hot water, a heating means 2, a heating pump 31, a remedy pump 32, a bathtub pump 33, a remedy heat exchanger 5, and a bath A bathtub 6 for storing hot water at around 40 ° C., a heating pipe 301, a water supply pipe 302, a bathtub return pipe 306a, a bathtub return pipe 306b, an additional return pipe 307a, an additional return pipe 307b, a control circuit 100, etc. ing.

  The hot water storage tank 1 is provided with, for example, six hot water storage temperature sensors 501a to 501f which are hot water storage temperature detection means arranged at predetermined intervals in the height direction. Although the number of the hot water storage temperature sensors 501a to 501f is six, the present invention is not limited to this, and a sufficient number of temperature sensors are provided to measure the temperature distribution inside the hot water storage tank 1. Also good. The heating means 2 is constituted by, for example, a heat pump cycle device, and is provided in the middle of a heating pipe 301 connecting the lower and upper parts of the hot water storage tank 1. The heating pump 31 is inserted into a heating pipe 301 between the hot water storage tank 1 and the heating means 2. The remedy pump 32 is provided in the middle of a remedy return pipe 307b that connects the remedy heat exchanger 5 and the side of the hot water storage tank 1. The bathtub pump 33 is provided in the middle of the bathtub return pipe 306 b that connects the remedy heat exchanger 5 and the bathtub 6.

  The bathtub going-out pipe 306a connects the remedy heat exchanger 5 and the bathtub 6, and the remedy going-out pipe 307a connects the upper part of the hot water storage tank 1 and the remedy heat exchanger 5. The water supply pipe 302 is a pipe for supplying city water from the lower part of the hot water storage tank 1. The memorial heat exchanger 5 heats the hot water in the hot water storage tank 1 that flows in the memorial delivery pipe 307a by the operation of the memorial pump 32 and the hot water in the bathtub 6 that flows in the bathtub return pipe 306b by the operation of the bathtub pump 33. Exchange. The control circuit 100 controls the heating operation of the heating means 2 and the operation of the heating pump 31, the remedy pump 32, and the bathtub pump 33.

  The heating pipe 301 is provided with a boiling temperature sensor 502 that detects the temperature of hot water heated by the heating means 2. The water supply pipe 302 is provided with a water supply temperature sensor 504 that detects the temperature of the inflowing water. In addition, a derivation temperature sensor 503 that detects the temperature of hot water derived from the hot water storage tank 1 is provided at the top of the hot water storage tank 1. The bathtub return pipe 306b is provided with a bathtub return temperature sensor 506 that detects the temperature of hot water flowing from the bathtub 6 into the memorial heat exchanger 5. The bathtub return temperature sensor 506 is also used as means for detecting the bathtub temperature by operating the bathtub pump 33 periodically.

FIG. 2 is a block diagram showing a circuit configuration of the hot water storage type hot water supply system according to Embodiment 1 of the present invention.
In FIG. 2, the control circuit 100 includes a tracking effective heat storage amount calculation unit 101a, a tracking load prediction unit 104a, a heating control unit 105, a tracking return temperature prediction unit 106, a target bathtub temperature setting unit 107, and the like. . The control circuit 100 receives temperature information detected by the hot water storage temperature sensors 501a to 501f, the boiling temperature sensor 502, the derived temperature sensor 503, the feed water temperature sensor 504, and the bath return temperature sensor 506, respectively. The control circuit 100 controls the heating means 2, the heating pump 31, the remedy pump 32, and the bathtub pump 33 based on each input temperature information. This control will be described later.

  The memorial load predicting means 104a predicts memorial loads based on the past measurable use results of the user, the current hot water temperature and the amount of hot water in the bathtub 6, or both information. The target bath temperature setting means 107 sets the temperature value input by the user's manual operation as the target bath temperature of the hot water of the bathtub 6 during the memorial operation. The remedy return temperature predicting means 106 has a target bathtub temperature set by the target bathtub temperature setting means 107 and the bathtub return detected by the bathtub return temperature sensor 506 (tub temperature detecting means) when the remedy operation is performed. Based on the temperature, the return temperature for returning to the hot water storage tank 1 from the additional heat exchanger 5 is predicted.

  The remedy effective heat storage amount calculation means 101a includes the remedy return temperature predicted by the remedy return temperature prediction means 106, the hot water storage temperature at each position in the height direction of the hot water storage tank 1 detected by the hot water storage temperature sensors 501a to 501f. Based on the above, among the heat storage amounts of the hot water in the hot water storage tank 1, the effective tracking heat storage amount effective for the tracking is calculated. The heating control unit 105 controls the heating operation of the heating unit 2 so that the calculated effective tracking heat storage amount is larger than the measured tracking load predicted by the tracking load prediction unit 104a.

  Next, the operation of the hot water storage type hot water supply system in the first embodiment will be described. In the following description, the operation will be described with specific numerical values, but the present invention is not limited to this.

[Basic operation]
First, the basic operation of the hot water storage type hot water supply system in the first embodiment will be described.
The hot water storage tank 1 stores low-temperature water (city water) flowing through the water supply pipe 302. The low-temperature water collected from the lower part of the hot water storage tank 1 is drawn into the heating pipe 301 by the heating pump 31 and guided to the heating means 2. The led low-temperature water is heated by the heating means 2 and boils into high-temperature hot water. The hot water flows from the upper part of the hot water storage tank 1 through the heating pipe 301 and is stored. On the other hand, hot water at around 40 ° C. for bathing is stored in the bathtub 6. The hot water in the bathtub 6 may be stored by supplying hot water stored in the hot water storage tank 1 through a hot water supply pipe (not shown), or hot water generated by a combustion type hot water supply device (not shown). It may be used and stored.

  The hot water stored in the upper part of the hot water storage tank 1 is the target bath temperature set in the target bath temperature setting means 107 by the bath temperature detected forcibly by the user's operation or periodically by the bath return temperature sensor 506. The chasing operation is automatically performed when the value becomes lower than the predetermined value. In this case, in order to raise the bath temperature, the hot water in the hot water storage tank 1 is guided to the memorial heat exchanger 5 through the memorizing forward piping 307a by the memorizing pump 32, and almost simultaneously with this timing, the bath 6 The hot water inside is guided to the memorial heat exchanger 5 through the bathtub return pipe 306b by the bathtub pump 33.

  The hot water of the tank system whose temperature has dropped due to heat applied to the bathtub system by the memory heat exchanger 5 returns to the hot water storage tank 1 through the memory return pipe 307b. At this time, the hot water of the bathtub system that has received heat at the memory heat exchanger 5 and has risen in temperature returns to the bathtub 6 through the bathtub outlet pipe 306a. Also, forcibly by the user's operation or automatically when the bathtub temperature detected by the bathtub return temperature sensor 506 is higher than the target bathtub temperature set in the target bathtub temperature setting means 107 by a predetermined value. The memorial operation ends.

  Thereby, low-temperature water is boiled by the heating means 2, and hot water is stored in the hot water storage tank 1, and hot water stored in the hot water storage tank 1 is used to replenish hot water in the bathtub 6. it can.

[Predicting memorial load]
Next, the operation for predicting the memory load will be described.
The memorial load is the amount of heat required to raise the hot water temperature (tub temperature) of the bathtub 6 from the current hot water temperature (hereinafter referred to as “current bath temperature”) to the target bath temperature. The memorial load is obtained by adding the temperature difference between the target bath temperature (for example, 40 ° C.) and the current bath temperature (for example, 30 ° C.) to the amount of hot water (for example, 200 L) of the bathtub 6, and the density (for example, 1 kg / L). And the specific heat (for example, 1 kcal / g ° C.).

  Here, as the amount of hot water in the bathtub 6, for example, a general value (for example, 200 L) may be used, or a value set by the user by operating the remote controller may be used. Further, in the case of a system that directly discharges hot water from the hot water storage tank 1 to the bathtub 6, a flow meter may be installed in the discharge path, and the amount of hot water in the bathtub 6 may be determined by an integrated value of the flow rate. In the system, for example, a water level detection means such as a pressure sensor is provided in the bathtub return pipe 306b, and when the hot water is directly discharged from the hot water storage tank 1 to the bathtub 6, an initial learning is made between the integrated flow rate and the water level. After that, the amount of hot water in the bathtub 6 estimated from the water level may be used.

  In the case of a system that learns and stores past memorial loads, the memorized load that is predicted on the day is predicted in the form of the maximum value or average value within a predetermined period in the past as the learning result. It may be. The learning of the remedy load may be learned by using a value calculated from the amount of hot water in the bathtub 6 and the temperature difference between the start and end of the remedy operation, or the bathtub return pipe 306b or the bathtub return pipe 306a. The circulating flow rate is calculated directly from the flow meter or indirectly from the control signal to the bathtub pump 33, and from the temperature difference between the inlet and outlet of the system on the bathtub 6 side of the additional heat exchanger 5. You may learn with a value.

[Calculation of effective memorial heat storage amount and control of heating means]
Next, a method for calculating the effective heat storage amount for tracking in the hot water storage tank 1 and the control of the heating means 2 based on the result will be described.
The hot water led from the hot water storage tank 1 to the memorial heat exchanger 5 through the memorizing piping 307a is supplied with heat to the bathtub system in the memorial heat exchanger 5, and the temperature is lowered. It is returned to the hot water storage tank 1 from the pipe 307b. Accordingly, the thermal energy that can be effectively used in memory among the thermal energy of the hot water in the hot water storage tank 1 is obtained by subtracting the hot water storage temperatures detected by the hot water storage temperature sensors 501a to 501f, respectively, by the return temperature. Only part.

  In other words, the zero point of the heat energy effective for the remedy (the remedy energy reference temperature) is the remedy return temperature from the remedy heat exchanger 5 to the hot water storage tank 1. Therefore, if the return temperature during the chasing operation is known, the temperature is set as the zero point of the heat energy, and as shown in FIG. ) Is calculated. In addition, between the water supply temperature 9 degreeC shown in the figure-the memorial return temperature Tbk, it is the amount of heat which is effective for hot water supply but is invalid for memorial.

The tracking return temperature is predicted by the tracking return temperature prediction means 106 as described above.
Hereinafter, a method for predicting the return return temperature and a method for calculating the additional effective heat storage amount will be described with reference to FIGS. 4 and 5.

  It is desirable to control the return temperature as low as possible so that the effective heat storage amount for the same hot water storage temperature distribution is as large as possible. In this case, the remedy return temperature substantially coincides with a value obtained by adding a predetermined temperature difference ΔTp1 (for example, 5 ° C.) depending on the heat exchange performance of the remedy heat exchanger 5 to the bath temperature. Therefore, the remedy return temperature changes during the remedy operation as shown in FIG. 4B, and the remedy effective heat storage amount is represented by the shaded area shown in FIG. 4A. In addition, in order to enlarge the memory effective heat storage amount, the temperature difference (DELTA) Tp1 is so preferable that it is small (refer FIG.4 (b)).

  For example, as shown in FIG. 5 (a), assuming that the bath temperature is constant as the target bath temperature, a predetermined temperature difference ΔTp1 depending on the performance of the additional heat exchanger 5 is added to the target bath temperature, and the return is performed. In the case of temperature, the effective heat storage amount can be estimated to be slightly small for easy and safe running out of hot water.

  Next, the heating means 2 is activated when the value of the predicted tracking load plus a predetermined margin is compared with the current tracking effective heat storage amount, and the tracking effective heat storage amount is smaller. Here, in consideration of the amount of heat heated by the heating means 2 during the chasing operation, the heating means 2 can be increased during the chasing operation from a value obtained by adding a predetermined margin to the predicted chasing load. You may compare the value which subtracted the remedy effective heat storage amount, and the present remedy effective heat storage amount.

  Further, the method for predicting the return temperature is not limited to the example described above. For example, as shown in FIG. 5B, the average value of the current bath temperature and the target bath temperature is obtained and assumed to be constant. Alternatively, a value obtained by adding a predetermined temperature difference ΔTp1 depending on the performance of the memory heat exchanger 5 may be used as the predicted memory return temperature. According to this method, as can be seen from FIG. 5B, the effective heat storage amount can be estimated more accurately in the hot water storage tank 1 only in the region where the hot water is used for reheating. In addition, when estimating the additional effective heat storage amount more accurately, the additional return temperature may be predicted using the fact that the temperature change of the bathtub 6 takes the form of the reciprocal of an exponential function.

  In addition, when the remedy return position where the remedy return pipe 307b is connected to the hot water storage tank 1 is not the lowermost part of the hot water storage tank 1, as shown in FIG. Alternatively, it may be excluded from the memorial effective heat storage amount. This is due to the following reason.

  The amount of effective heat storage in the area below the recuperation return position is raised by mixing the medium and low temperature hot water returned from the recuperation heat exchanger 5, and the heated hot water is circulated again to the top of the hot water storage tank 1 again. Is transmitted to the bathtub 6 side only in the form of being sent to the heat exchanger 5 and radiating heat to the bathtub 6 side. However, the temperature of the heated hot water is generally not high, and the remedy ability at this time shows a small value, so by removing the area below the remedy return position from the remedy effective heat storage amount, It is possible to maintain the memorial ability while driving.

  As described above, in Embodiment 1, the effective heat storage amount of the hot water storage tank 1 that is effective for the predicted additional load is calculated based on the tank temperature distribution (hot water temperature), the bath temperature, and the bath target temperature. Then, the heating operation of the heating means 2 is controlled so that the calculated value becomes larger than the predicted tracking load. As a result, it is possible to calculate the amount of effective heat storage required in the hot water storage tank 1 with high accuracy with respect to the predicted heat load, and avoid running out of hot water with the smallest amount of effective heat storage possible. Thus, heat dissipation loss can be minimized. Therefore, it is possible to realize a hot water storage hot water supply system with high energy saving performance.

  Further, in the first embodiment, the memory return temperature is calculated as a value obtained by adding a predetermined temperature difference ΔTp1 to the target bath temperature. As a result, it is possible to easily calculate the amount of effective heat storage required for the hot water storage tank 1 with respect to the predicted heat load, and to avoid running out of hot water with the smallest amount of effective heat storage required. Thus, heat dissipation loss can be minimized. Therefore, a hot water storage hot water supply system with high energy saving can be realized more easily.

  In the first embodiment, the return temperature is calculated as a value obtained by adding a predetermined temperature difference ΔTp1 to the average value of the target bath temperature and the current bath temperature. As a result, it is possible to easily and accurately calculate the amount of effective heat storage required for the hot water storage tank 1 with respect to the predicted additional load, and avoid running out of hot water with the smallest possible effective heat storage amount. And heat dissipation loss can be minimized. Therefore, a hot water storage hot water supply system with high energy saving can be realized more simply and with high accuracy.

  Further, in the first embodiment, since the heat storage amount in the region below the recuperation return position in the hot water storage tank 1 is excluded, hot water can be cut out with as little heat storage amount as possible while maintaining a high regenerative capability. This can be avoided and heat dissipation loss can be minimized. Accordingly, it is possible to realize a hot water storage hot water supply system with higher user satisfaction and higher energy savings.

Embodiment 2. FIG.
In the second embodiment, the calculation of the effective heat storage amount in the hot water storage tank and the control of the heating means based on the calculated value will be described in a situation where not only the hot water load but also the hot water supply load is predicted. In addition, in the configuration of the hot water storage type hot water supply system in the second embodiment, the same reference numerals are given to the same parts as those in the first embodiment.

FIG. 7 is a schematic diagram showing a configuration of a hot water storage type hot water supply system according to Embodiment 2 of the present invention.
The hot water storage hot water supply system in the second embodiment includes the mixing means 4, the outlet pipe 303, the mixing pipe 304, the hot water supply pipe 305, etc. in addition to the components provided in the hot water storage hot water supply system in the first embodiment. Yes.

  The mixing means 4 is composed of, for example, an electric three-way mixing valve. One outlet is connected to the outlet pipe 303 connected to the upper part of the hot water storage tank 1, and the other inlet is branched from the water supply pipe 302. A mixing pipe 304 is connected. A hot water supply pipe 305 is connected to the outlet. The mixing means 4 adjusts the mixing ratio between the amount of hot water and the amount of water based on the control from the control circuit 100. The hot water supply pipe 305 is a pipe for supplying hot water mixed by the mixing means 4 to the load side (tub 6) to be used, and a hot water tap (not shown) is provided on the tip side. The hot water supply pipe 305 is provided with a hot water supply temperature sensor 505 for detecting the temperature of hot water used on the load side, and a hot water supply flow rate sensor 601 for detecting the amount of hot water used on the load side.

FIG. 8 is a block diagram showing a circuit configuration of a hot water storage type hot water supply system according to Embodiment 2 of the present invention.
In FIG. 8, the control circuit 100 includes a hot water supply effective heat storage amount calculation unit 101b, a hot water supply necessary heat storage amount prediction unit 104b, and the like. The control circuit 100 determines the opening degree of the valve of the mixing unit 4 based on the time information from the time detection unit 602 (timer), the hot water supply temperature detected by the hot water supply temperature sensor 505 and the hot water supply amount detected by the hot water supply flow rate sensor 601. Control.

  The hot water supply effective heat storage amount calculation means 101b calculates the hot water supply effective heat storage amount effective for hot water out of the heat storage amount of the hot water in the hot water storage tank 1 based on the hot water storage temperatures detected by the hot water storage temperature sensors 501a to 501f. . The required hot water storage heat amount predicting means 104b predicts the required hot water storage amount necessary for avoiding running out of hot water with respect to the predicted hot water supply load, based on the past hot water use history of the user or a predetermined design value. To do.

Next, the operation of the hot water storage type hot water supply system in the second embodiment will be described. In the following description, the operation will be described with specific numerical values, but the present invention is not limited to this. In the basic operation of the hot water storage type hot water supply system according to the second embodiment, portions different from the first embodiment will be described.
[Basic operation]
Hot water stored in the upper part of the hot water storage tank 1 flows out from the outlet piping 303 in response to a request for direct discharge of hot water from the load side, and is guided to the mixing means 4. The mixing means 4 guides water through the mixing pipe 304 branched from the water supply pipe 302, mixes it with the hot water introduced from the hot water storage tank 1, and passes through the hot water supply pipe 305 to an appropriate temperature (for example, 42 ° C.). Supply hot water.

[Prediction of necessary heat storage for hot water supply]
Next, the operation | movement which estimates the required heat storage amount for hot water supply is demonstrated.
The necessary amount of stored heat for hot water supply is predicted based on the past use of hot water supply by the user or a predetermined design value. When based on the past use history of hot water supply of the user, for example, the hot water supply load results for each time zone are stored every day based on the information from the time detection means 602, the hot water supply temperature sensor 505, and the hot water supply flow rate sensor 601, and the stored hot water supply is stored. There is a method of predicting the hot water supply load on the current day based on the load and predicting the necessary heat storage amount for hot water supply so that hot water shortage does not occur with respect to the predicted hot water supply load. Moreover, when based on a predetermined design value, for example, in a time zone in which a large amount of hot water supply is generally predicted (for example, from 6:00 pm to 11:00 pm), the required heat storage amount for hot water supply is designed to be large (for example, 42 L converted to 300 L). However, there is a method in which the other time zones are designed to be small (for example, 80 L converted to 42 ° C.).

[Calculation of effective hot water storage amount]
In hot water supply, the thermal energy of hot water in the hot water storage tank 1 is used by mixing it with city water by mixing, so the zero point (hot water supply energy reference temperature) of heat energy effective for hot water supply is the water supply temperature of city water. Therefore, the hot water supply effective heat storage amount is calculated by integrating the tank volume with the water supply temperature as the zero point of the heat energy.

[Calculation of memorial effective heat storage]
Hereinafter, a method for calculating the effective heat storage amount when the hot water supply load is predicted will be described with reference to FIG.
The memorial effective heat storage amount calculation unit 101a is configured to reach a position where the hot water supply effective heat storage amount calculated by the hot water supply effective heat storage amount calculation unit 101b is at least equal to the required hot water storage heat storage amount predicted by the hot water supply required heat storage amount prediction unit 104b. The effective heat storage amount is calculated except for the area.

  As shown in FIG. 9, the area assumed to be used for hot water supply is arranged above the area assumed to be used for hot water, and the hot water energy reference temperature is higher than the hot water energy reference temperature, and This is because the hot water storage temperature is higher in the upper part than in the lower part in the hot water storage tank 1. If the arrangement is reversed, as shown in FIG. 10, even if the hot water supply effective heat storage amount and the additional heat storage effective heat amount are more than the required heat storage amount for hot water supply, respectively, the heat storage amount is insufficient. As a result, hot water may run out.

  As described above, according to Embodiment 2, the hot water supply effective heat storage amount is accumulated from the upper part of the hot water storage tank 1 downward, and the value is predicted by at least the required hot water storage heat amount prediction means 104b. The region up to the position equal to the amount is assumed to be a region for use in hot water supply, and the effective heat storage amount is calculated excluding that region. Thereby, even in a situation where a hot water supply load is assumed in addition to the renewal load, it is possible to avoid running out of hot water with a minimum amount of heat storage, and to minimize heat dissipation loss. Therefore, it is possible to realize a hot water storage hot water supply system with high energy saving performance.

  DESCRIPTION OF SYMBOLS 1 Hot water storage tank, 2 Heating means, 31 Heating pump, 32 Reheating pump, 33 Bath pump, 4 Mixing means, 5 Reheating heat exchanger, 6 Bath, 100 Control circuit, 101a Renewal effective heat storage amount calculation means 101b hot water supply effective heat storage amount calculation means, 104a additional heat load prediction means, 104b required heat storage amount prediction means for hot water supply, 105 heating control means, 106 additional return temperature prediction means, 107 target bath temperature setting means, 301 heating pipe, 302 water supply pipe, 303 lead-out pipe, 304 mixing pipe, 305 hot water supply pipe, 306a bathtub return pipe, 306b bathtub return pipe, 307a additional return pipe, 307b additional return pipe, 501a to 501f hot water storage temperature sensor, 502 Boiling temperature sensor, 503 Derived temperature sensor, 504 Feed water temperature sensor, 505 Hot water temperature sensor, 506 bath return temperature sensor, 601 hot water flow sensor, 602 time detecting means.

Claims (7)

Heating means for heating the water to hot water;
A hot water storage tank for storing hot water heated by the heating means;
Hot water storage temperature detecting means for detecting the temperature of hot water in the hot water storage tank (hereinafter referred to as “hot water storage temperature”);
Control means for controlling the heating operation of the heating means;
A recuperation heat exchanger that replenishes the hot water in the bathtub using the amount of hot water derived from the hot water storage tank;
The control means includes
A memorizing return temperature predicting means for predicting a memorizing return temperature of hot water that passes through the memorial heat exchanger and returns to the hot water storage tank;
Based on the return return temperature predicted by the return return temperature prediction means and the hot water storage temperature detected by the hot water storage temperature detection means, the amount of heat stored in the hot water in the hot water storage tank is effective for reheating. A memorial effective heat storage amount calculating means for calculating a memorial effective heat storage amount;
A renewal load predicting means for predicting a renewal load that is the amount of heat of hot water supplied to the bathtub by reheating,
The heating operation of the heating unit is controlled so that the effective tracking heat storage amount calculated by the tracking effective heat storage amount calculating unit is larger than the tracking load predicted by the tracking load predicting unit. Hot water storage hot water system. A target bath temperature setting means for setting a target bath temperature that is a target value of the hot water temperature of the bath at the time of remembrance,
The hot water storage type hot water supply system according to claim 1, wherein the additional return temperature predicting means predicts the additional return temperature based on the target bath temperature. A bath temperature detecting means for detecting a bath temperature which is a temperature of hot water in the bath,
The remedy return temperature predicting means predicts the remedy return temperature based on the target bath temperature set in the target bath temperature setting means and the bath temperature detected by the bath temperature detecting means. Item 3. A hot water storage hot water supply system according to item 2.   The remedy effective heat storage amount calculation means uses the remedy return temperature predicted by the remedy return temperature prediction means as a reference temperature, and the hot water storage tank in which the hot water temperature detected by the hot water storage temperature detection means is equal to or higher than the reference temperature. The hot water storage type hot water supply system according to any one of claims 1 to 3, wherein a value obtained by integrating thermal energy having the reference temperature as a zero point over an inner region is set as a memorized effective heat storage amount.   The remedy effective heat storage amount calculating means is located below the position in the hot water storage tank where the hot water storage temperature is equal to or higher than the reference temperature, and the position where the hot water that has passed through the remedy heat exchanger is returned to the hot water storage tank. 5. The hot water storage type hot water supply system according to claim 4, wherein a remnant effective heat storage amount is calculated excluding the region. A hot water tap that supplies hot water in the hot water storage tank to the load side by hot water supply that is directly discharged,
The control means includes
Based on the hot water storage temperature detected by the hot water storage temperature detection means, the hot water supply effective heat storage amount calculating means for calculating the hot water supply effective heat storage amount effective for hot water supply among the heat storage amounts of the hot water in the hot water storage tank;
A necessary heat storage amount prediction means for hot water supply for predicting a necessary heat storage amount for hot water supply for avoiding running out of hot water for a hot water supply load directly discharged from the hot water tap,
The memorial effective heat storage amount calculating means is configured such that the hot water supply effective heat storage amount calculated by the hot water supply effective heat storage amount calculation means is at least equal to the required hot water storage heat storage amount predicted by the hot water supply required heat storage amount prediction unit. The hot water storage type hot water supply system according to any one of claims 1 to 5, wherein a remnant effective heat storage amount is calculated excluding the region.   The hot water supply effective heat storage amount calculation means uses the temperature of city water supplied to the hot water storage tank as a reference temperature, and based on the hot water storage temperature detected by the hot water storage temperature detection means, heat energy having the reference temperature as a zero point The hot water storage type hot water supply system according to claim 6, wherein a value obtained by integrating the values from the upper part of the hot water storage tank is used as an effective hot water storage amount.

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