JP2005140441A - Hot water supply device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize a hot water supply device never causing shortage of hot water in a hot water storage tank at the time of bath reheating. <P>SOLUTION: This device comprises the hot water storage tank 11; a plurality of residual hot water temperature detection means 28, 29 and 30; a heating means 14; a reheating heat exchanger 22 provided out of the storage tank 11; a high-temperature hot water temperature detection means 25 for detecting the primary-side temperature of the reheating heat exchanger; a bathtub hot water temperature detection means 27 for detecting the secondary-side temperature of the reheating heat exchanger; a setting means 20 for setting a bath hot water temperature; a first arithmetic part 31 for computing a reheating necessary heating value by use of a predetermined arithmetic equation from the bath setting temperature and the bath hot water temperature; and a second arithmetic part 31 for computing the residual hot water heating value in each residual hot water position by use of a predetermined arithmetic equation from the residual hot water temperatures. At the time of bath reheating, an additional boiling time by a heating means is determined based on the reheating necessary heating value determined by the first arithmetic part 31 and the residual hot water heating value determined by the second arithmetic part 31. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a hot water outflow prevention sequence of a hot water storage type water heater having a bath replenishing function.

  This type of conventional hot water supply apparatus is provided with heaters at the upper and lower parts of the hot water storage tank, and a reheating heat exchanger for exchanging heat with the hot water in the tank is built above the upper heater. The bath water is recirculated in the bath to replenish the bath. While the bath water is circulating, the upper heater is energized, and the hot water temperature at the top of the hot water storage tank before heat exchange is detected. In addition, after the heat exchange, the upper heater is energized to return the hot water temperature at the upper part of the hot water storage tank to the original temperature, or the heater is energized by the amount of heat exchanged by the reheating heat exchanger. There was what was made to heat (for example, refer to patent documents 1).

FIG. 8 shows a conventional hot water supply apparatus described in the publication. As shown in FIG. 8, the bath is reheated by the bath reheating heat exchanger 2 configured in the hot water storage tank 1, and the hot water temperature in the hot water storage tank 1 is detected by the remaining hot water thermistor 3. When the hot water temperature of the remaining hot water thermistor 3 falls below 60 ° C., the heating device 4 (heat pump) is operated and boils up to 70 ° C. At the time of bathing, the hot water in the hot water storage tank 1 and the hot water circulated by the bath pump 5 are heat-exchanged to raise the bath water temperature. The hot water temperature of the hot water storage tank 1 is configured to determine whether to boil up based on the temperature detected by the remaining hot water thermistor 3 regardless of bathing.
Japanese Patent Laid-Open No. 11-83156

  However, in the above-described conventional hot water supply device, when the remaining amount of hot water in the hot water storage tank is small or the hot water temperature is low at the start of bath reheating, there is remaining hot water that can be used for reheating in the hot water storage tank during bath reheating. If there is a problem that the heater is turned on while heating the bath, the heating operation is performed even if there is a sufficient amount of remaining hot water remaining in the hot water storage tank. Therefore, useless boiling is performed.

  Furthermore, since the conventional water heater has a built-in heat exchanger in the hot water tank, natural convection occurs due to heat exchange when the bath water is circulated during bathing, and the hot water temperature in the hot water tank is totally There exists a subject that it will fall and cannot secure high temperature water.

  The present invention solves the above-mentioned problem, and is configured to store hot water in a hot water tank in a stacked state in order from the top, and to exchange heat with the bath water from the upper part of the hot water tank, reheating heat exchange This is a hot water supply device that uses an external heat exchange system that returns to the bottom of the hot water storage tank via a water heater. At the start of reheating the bath, it was determined that the remaining hot water in the hot water storage tank was insufficient based on the amount of heat required for reheating. In this case, an object of the present invention is to provide a hot water supply device that boils the hot water storage tank so as to prevent the hot water from running out when the bath is replenished in order to secure a necessary amount of hot water in the hot water storage tank.

  In order to solve the above-described conventional problems, the hot water supply apparatus of the present invention heats a hot water storage tank, a plurality of remaining hot water temperature detection means provided on the surface of the hot water storage tank, and circulates from the lower part to the upper part of the hot water storage tank. Heating means, reheating heat exchanger for exchanging heat with bathtub water while circulating from the upper part to the lower part of the hot water storage tank, and high temperature hot water temperature detecting means for detecting the temperature of circulating water flowing on the primary side of the reheating heat exchanger; A bath water temperature detecting means and a hot water bath temperature detecting means for detecting an inlet temperature of the bath water flowing through the secondary side of the reheating heat exchanger and an outlet temperature after the heat exchange, and a setting means for setting the bath temperature; A first calculation unit that calculates a reheating required heat amount from a bath set temperature set by the setting means and a bath water temperature detected by the bathtub hot water temperature detection means using a predetermined calculation formula; and the remaining hot water temperature detection From the remaining hot water temperature detected by the means And a second calculating unit that calculates the amount of remaining hot water at each remaining hot water position using the calculation formula, and calculated by the second calculating unit and the reheating required heat amount determined by the first calculating unit when bathing The additional boiling time by the heating means is obtained based on the amount of remaining hot water.

  Thus, with reference to the amount of heat necessary for reheating obtained by the first calculation unit, the amount of remaining hot water in the hot water storage tank is sequentially compared with the amount of remaining hot water at each remaining hot water position of the hot water storage tank obtained by the second calculation unit. If there is a shortage of heat, it is possible to select only the amount of heat necessary for reheating and secure the remaining amount of hot water in the hot water storage tank, so that it is possible to realize reheating operation without running out of hot water without wasteful boiling. .

  The hot water supply apparatus of the present invention is a circulation circuit that takes out high temperature water from the upper side of a hot water storage tank in which hot water is stored in a stacked state sequentially from the upper part, returns the hot water after heat exchange to the lower part of the hot water storage tank through a reheating heat exchanger Since the hot water operation is always performed by the hot water supplied from the hot water storage tank and the bathtub water, the hot water can be reheated to the desired temperature in a short time. Furthermore, even when a hot water supply operation is requested during or after reheating, hot water at a desired temperature can be supplied using the high-temperature water remaining in the upper part of the hot water storage tank.

  In addition, when the amount of remaining hot water in the hot water storage tank is small, an appropriate amount of remaining hot water should be ensured by comparing with the amount of remaining hot water determined at each remaining hot water position based on the amount of heat required for reheating obtained in advance. Since the additional boiling time is obtained, it is possible to realize a reheating operation without wasteful boiling and without running out of hot water.

  The first invention is a hot water storage tank, a plurality of remaining hot water temperature detecting means provided on the surface of the hot water tank, heating means for heating while circulating from the lower part of the hot water tank to the upper part, and circulation from the upper part of the hot water tank to the lower part. Reheating heat exchanger for exchanging heat with bath water, high temperature hot water detecting means for detecting the temperature of circulating water flowing on the primary side of the reheating heat exchanger, and the secondary side of the reheating heat exchanger Bath water temperature detecting means and hot bath water temperature detecting means for detecting the inlet temperature of the flowing bath water and the outlet temperature after heat exchange, setting means for setting the bath temperature, and the bath setting temperature set by the setting means A first calculation unit that calculates the amount of heat required for reheating from a bath water temperature detected by the bath water temperature detection means using a predetermined equation, and a predetermined calculation from the remaining hot water temperature detected by the remaining hot water temperature detection means The remaining amount at each remaining hot water position using the equation A second calculating unit that calculates the amount of heat, and an additional boiling time by the heating means is calculated based on the amount of heat required for reheating obtained by the first calculating unit and the amount of remaining hot water determined by the second calculating unit when bathing It is characterized by the fact that it is calculated, and sequentially compared with the amount of remaining hot water at each remaining hot water location of the hot water storage tank determined by the second arithmetic unit, based on the amount of heat required for reheating determined by the first arithmetic unit. However, if the amount of remaining hot water in the hot water storage tank is insufficient, the amount of heat remaining in the hot water storage tank can be secured by selecting only the amount of heat necessary for reheating, so that hot water can be heated without wasting water. A continuous driving operation can be realized.

  In the second invention, when the additional boiling time is obtained, the remaining hot water calorie is obtained in order from the remaining hot water temperature detecting means provided above using the second arithmetic unit, and is compared with the reheating necessary heat amount. The amount of remaining hot water in the hot water storage tank is calculated using a predetermined calculation formula for each of the remaining hot water temperature detecting means attached to the tank surface, and the amount of heat required to be replenished sequentially from the upper remaining hot water heat amount. By comparing with, it is possible to obtain the appropriate amount of remaining hot water necessary for reheating, and by performing additional boiling only for the time to secure the remaining hot water, without making useless boiling, It is possible to achieve a chasing operation without running out of hot water.

  According to a third aspect of the present invention, when the temperature detected by the remaining hot water temperature detecting means provided at the uppermost level at the time of bathing is below a predetermined temperature, the chasing operation is stopped and the remaining hot water temperature detecting means at a predetermined position is stopped. When a predetermined temperature is detected, the reheating operation is started. If there is no remaining hot water at the top of the hot water storage tank, the reheating operation is performed. Even if instructed to do so, the reheating operation is not performed. First, an additional boiling operation of the hot water storage tank is performed, and the reheating operation is performed when a predetermined remaining hot water temperature detecting means detects a temperature at which the reheating operation can be performed. Thus, it is possible to avoid an unnecessary chasing operation and to secure an effective chasing operation.

  According to a fourth aspect of the present invention, a cumulative hot water detection circuit is provided in a hot water bath circuit that joins the secondary side of the reheating heat exchanger, and when the required reheating heat amount is obtained, based on the amount of hot water detected by the cumulative flow detecting device. It is characterized in that the calculation is performed using the first calculation unit, and the amount of heat required for reheating is accurately determined as a reference for determining whether or not the additional boiling operation of the hot water storage tank is performed during the reheating operation. By obtaining a more accurate amount of remaining hot water, it is possible to achieve a reheating operation without running out of hot water without wasteful boiling.

  The fifth invention is characterized in that the hot water temperature by the heating means at the time of chasing the bath is operated at the maximum setting, and the remaining time of hot water is secured to shorten the chasing time. In addition, an efficient boiling operation can be secured by reducing the amount of remaining hot water as much as possible.

  A sixth invention includes a time function and an accumulated time counter, and reflects the bath replenishment time of the past specific period detected by the accumulated time counter in the heating operation time performed in the night time zone of the next day. The accumulated boiling time counter detects the additional boiling time during reheating operation during the daytime hours, and this detection time is used for normal boiling during the nighttime hours when the rate is low by learning control. By reflecting in the driving operation, it is possible to maintain the amount of tank heat that matches the actual usage, and suppress the additional boiling operation during reheating operation during daytime hours, and ensure efficient boiling operation. be able to.

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

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

  In FIG. 1, the hot water supply apparatus includes a hot water storage tank unit 10 and a heat source unit 14 using a heat pump unit as a heating means, and the hot water storage tank unit 10 and the heat source unit 14 are connected by piping.

  The hot water storage tank unit 10 is connected by piping from the hot water storage tank 11 and the intake port 12a below it to the heat source part 14 via the boiling pump 13, and from the heat source part 14 to the upper supply port 12b of the hot water storage tank 11. A boiling circuit is formed. The hot water storage tank 11 is supplied with water through the pressure reducing valve 15 and then supplied from the water supply port 12c at the bottom of the tank.

  A hot water supply circuit for the hot water storage tank 11 includes a hot water supply circuit that supplies water to a currant or the like from the upper hot water outlet 12d via the hot water supply mixing valve 16a, a hot water solenoid valve 17 that passes through the bath mixing valve 16b, and a flow rate sensor. A pouring circuit for supplying water to the bath 18 through 32 and a high temperature hot water outlet 23 provided separately from the hot water outlet 12d through the primary side path of the bath reheating heat exchanger 22 and the bottom of the tank by the reheating pump 24 A recirculation circuit connected to the return port 12e is formed.

  The secondary side path of the reheating heat exchanger 22 that exchanges heat with the bath water joins the pouring circuit from the bath 18 via the bath circulation pump 26, and then the second path of the reheating heat exchanger 22. A bath circulation circuit that returns to the bath 18 through the secondary path is formed.

  A plurality of remaining hot water thermistors are arranged on the surface of the hot water storage tank 11 at appropriate positions in the height direction to form a remaining hot water temperature detecting means. The remaining hot water thermistor includes a first remaining hot water thermistor 30 at the upper part of the hot water storage tank 11, and a second remaining hot water thermistor 29, a third remaining hot water thermistor 28, a fourth remaining hot water thermistor 33, and a fifth remaining hot water thermistor. 34 is attached.

  Further, as a hot water temperature detecting means for detecting the temperature of the circulating water flowing through the reheating circulation circuit, a high temperature hot water thermistor 25 is disposed at the primary side outlet of the reheating heat exchanger 22 and flows through the bath circulation circuit. A bath thermistor 27 and a reheating thermistor 19 are provided as a bath water temperature detecting means for detecting the bath water temperature and a hot bath water temperature detecting means.

  The bath temperature is set by the bath remote controller 20, and the information is sent to the controller 21 to control various loads including the heat source unit 14 to perform a predetermined operation.

  In the hot water supply apparatus configured as described above, first, the operation of boiling the hot water storage tank 11 is performed when an operation instruction is given by the bath remote controller 20, and hot water in the hot water storage tank 11 is heated from the water intake 12 a by the boiling pump 13. 14. In the heat source unit 14, a heat pump cycle is driven based on a predetermined sequence to heat a refrigerant (for example, CO 2 refrigerant) and exchange heat with hot water supplied from the hot water storage tank 11 to raise the temperature to a predetermined temperature. From the supply port 12b, the hot water storage tank 11 is stored in a stacked state from above. By repeating this circulation, the hot water in the hot water storage tank 11 is stored in a high temperature state sequentially from the top. This boiling operation is generally a method in which the entire amount of the hot water storage tank 11 is heated up to a set temperature by late-night power supplied in the night time zone of PM 23: 00 to AM 7:00. Can be heated even in daytime hours, and even if it is not heated all at night, it can be heated up as much as necessary, and sudden shortages can be raised in daytime hours. To be done. The present invention relates to performing the efficient operation during the additional boiling operation that compensates for the shortage of the amount of boiling water generated when the bath is refilled in the latter usage.

  In the boiling operation, the heating temperature is adjusted by controlling the boiling pump 13 and adjusting the flow rate.

  Next, in the bath hot water filling operation, hot water supplied from the upper hot water outlet 12d of the hot water storage tank 11 and water supplied via the pressure reducing valve 15 are mixed by the bath mixing valve 16b, and the pouring electromagnetic valve 17 is opened. As a result, the flow rate sensor 32 supplies the bath 18 while detecting the amount of hot water filling. The hot water filling temperature at this time is adjusted so that the bath mixing valve 16b is controlled to a predetermined temperature by inputting the temperature detected by the reheating thermistor 19 to the controller 21.

  The basic operation of reheating the bath is to drive the reheating pump 24, and from the high temperature hot water outlet 23 provided at the top of the hot water storage tank 11, to the primary side path of the reheating heat exchanger 22, the upper high temperature water of the hot water storage tank 11. Are sequentially supplied, and the hot water after the heat exchange is returned to the return port 12e at the bottom of the tank. At the same time, the bath pump 26 is driven to repel the bath water of the bath 18 and flow it to the secondary side path of the heat exchanger 22. By repeating the circulation operation on the primary side and the secondary side of the reheating heat exchanger 22, the bath reheating operation is performed by exchanging heat between the hot water and the bath water.

  Next, the bath chasing operation will be described in detail with reference to the flowcharts of FIGS. FIG. 2 is an operation flowchart for calculating the boiling time when additional boiling is performed during the reheating operation, FIG. 3 is an operation flowchart in which a step of performing the heating operation after the boiling time calculation is added, and FIG. It is an operation | movement flowchart at the time of using the method of calculating the calorie | heat amount required for a chasing from quantity.

When the instruction of reheating by bath remote controller 20 operation is performed, check the temperature t _TK first remaining hot water thermistor 30 is first attached to the tank top is detected, the value which the temperature is predetermined (e.g., 60 ° C.) or higher In the above case, the reheating operation is started, and in the following case, the reheating operation is stopped and the tank is heated. The hot water is stored in the tank 11 by the boiling operation, and when the predetermined remaining hot water thermistor, for example, the second remaining hot water thermistor 28 detects a predetermined temperature, the reheating operation is started.

ここで、Ｑ_Ｐ：風呂循環流量、ｔ_ＦＳ：風呂設定温度、ｔ_ＦＪ：風呂サーミスタ２７の検出温度である。ただし、風呂循環流量を検出するセンサを設けない場合は固定値を用いて演算する。 When the chasing operation is started, first, the amount of heat necessary for chasing the bath side is calculated using (Equation 1).

Here, Q _{P is the} bath circulation flow rate, t _{FS is the} bath set temperature, and t _FJ is the temperature detected by the bath thermistor 27. However, when a sensor for detecting the bath circulation flow rate is not provided, calculation is performed using a fixed value.

ここで、Ｑ_ＴＢ：高温湯取出口から第２残湯サーミスタ２８間の貯湯量、ｔ_ＴＫ：高温湯サーミスタ２５の検出温度、ｔ_ＺＢ：第２残湯サーミスタ２８の検出温度である。 Next, each remaining hot water temperature detection position of the hot water storage tank 11, for example, the remaining hot water heat amount in the second remaining hot water thermistor 28 is calculated using (Equation 2).

Here, Q _{TB is the} amount of hot water stored between the high temperature hot water outlet and the second remaining hot water thermistor 28, t _{TK is} the detected temperature of the high temperature hot water thermistor 25, and t _ZB is the detected temperature of the second remaining hot water thermistor 28.

上記演算により追加沸き上げ時間が求まると、追い焚き動作を行いながら所定の残湯熱量を確保すべく沸き上げ動作を行う。上記演算式では、風呂追い焚き中に湯切れせず、安価に運転できるように、沸き上げ温度として６０℃を設定したが、図５のフローチャートに示すように、設定温度として最高温度、例えば９０℃を設定してもよく、温度を高く設定すると沸き上げ時間は多少長くなるが、沸き上げ湯量は少なくてすみ、かつ追い焚き時間が短縮できるという効果を奏することができる。 Next, in order to compare the amount of heat required for reheating obtained by the above calculation and the amount of remaining hot water in the second remaining hot water thermistor 28, it is determined whether or not each of the heat amount ratios is 1 or more. When the amount of heat is larger than the amount of heat required for reheating, the reheating operation is continued as it is, and the additional boiling of the tank is not performed. If it is 1 or more, that is, if it is determined that the remaining hot water heat amount is insufficient, then the remaining hot water heat amount in the third remaining hot water thermistor 29 is calculated in the same manner using the above (Equation 2), and the reheating required heat amount is obtained. Compare with If the comparison result is 1 or less, the additional boiling time T _K is calculated using (Equation 3).
Computes, if the comparison result is one or more computing the additional water heating time T _K using equation (4).

When the additional boiling time is obtained by the above calculation, the boiling operation is performed to secure a predetermined amount of remaining hot water while performing the reheating operation. In the above calculation formula, 60 ° C. is set as the boiling temperature so that the hot water does not run out during bathing and can be operated at a low cost. However, as shown in the flowchart of FIG. C. may be set. If the temperature is set high, the boiling time becomes somewhat longer, but the amount of boiling water can be reduced, and the effect of shortening the reheating time can be achieved.

  Furthermore, as shown in the flowchart of FIG. 6, when the hot water thermistor 25 falls below a predetermined temperature (minimum temperature required for reheating, for example, 60 ° C.) during additional boiling during reheating, the reheating operation is stopped. Then, after performing the predetermined boiling operation, if the reheating operation is started again, the hot water cooling by the bath reheating operation when a large amount of hot water is used on the hot water supply side during the additional boiling operation is prevented, Efficient operation is possible.

  FIG. 7 is another operation flowchart in which the heating time of the hot water storage tank 11 is accumulated for a specific period (for example, one week), and the maximum daytime heating time is added to the nighttime heating time of the next day.

  In the additional boiling operation described above, the hot water storage tank 11 is heated so that the hot water does not run out at the time of bathing. However, from the viewpoint of running cost, it is more advantageous to heat the hot water storage tank at night than in the daytime. Thus, the maximum daytime heating time for a specific period in the past is intended to reduce running costs by boiling up at night on the next day.

  As described above, in the hot water supply apparatus according to the present invention, high-temperature water and bathtub water supplied from the hot water storage tank are always heat-exchanged in the reheating operation, and can be reheated to a desired temperature in a short time. Even when there is a request for hot water supply during or after reheating, hot water at the desired temperature can be supplied using the high temperature water remaining in the upper part of the hot water storage tank. If the amount is small, the additional boiling time should be calculated so as to ensure an appropriate amount of remaining hot water compared to the amount of remaining hot water determined at each remaining hot water position based on the amount of heat required for reheating. Therefore, since it is possible to realize a reheating operation without wasteful boiling without running out of hot water, the present invention can be applied to a combination of a hot water storage type water heater and an external heat exchanger, for example, a heating operation.

The system block diagram of the hot water supply apparatus in Embodiment 1 of this invention Operation flowchart of the water heater Other operation flowchart of the hot water supply apparatus Other operation flowchart of the hot water supply apparatus Other operation flowchart of the hot water supply apparatus Other operation flowchart of the hot water supply apparatus Other operation flowchart of the hot water supply apparatus System configuration diagram of a conventional water heater

Explanation of symbols

11 Hot water storage tank 19 Reheating thermistor 20 Bath remote control (setting means)
22 Bath reheating heat exchanger 25 High temperature hot water thermistor 27 Bath thermistor 28 Second remaining hot water thermistor (remaining hot water temperature detecting means)
29 Third remaining hot water thermistor (remaining hot water temperature detection means)
30 1st remaining hot water thermistor (remaining hot water temperature detection means)
31 arithmetic unit (first and second arithmetic units)
33 Fourth remaining hot water thermistor (remaining hot water temperature detection means)

Claims (6)

Hot water storage tank, a plurality of remaining hot water temperature detection means provided on the surface of the hot water storage tank, heating means for heating while circulating from the bottom to the top of the hot water tank, and bath water and heat while circulating from the top to the bottom of the hot water tank Reheating heat exchanger to be exchanged, high temperature hot water temperature detecting means for detecting the temperature of circulating water flowing on the primary side of the reheating heat exchanger, and inlet of bath water flowing on the secondary side of the reheating heat exchanger Bath temperature detection means and hot bath temperature detection means for detecting temperature and outlet temperature after heat exchange, setting means for setting bath temperature, bath set temperature set by the setting means and bath temperature detection means A first calculation unit that calculates a reheating required heat amount from a bath water temperature detected by using a predetermined calculation formula, and a remaining calculation using a predetermined calculation formula from the remaining hot water temperature detected by the remaining hot water temperature detection means. Calculate the amount of remaining hot water at the hot water location And a second arithmetic unit, and the additional boiling time by the heating means is obtained based on the amount of heat required for reheating obtained by the first arithmetic unit and the amount of remaining hot water obtained by the second arithmetic unit when bathing. Hot water supply device. The hot water supply according to claim 1, wherein when the additional boiling time is obtained, the remaining hot water calorific value is obtained by using the second arithmetic unit in order from the remaining hot water temperature detecting means provided above, and compared with the reheating required heat amount. apparatus. When the temperature detected by the remaining hot water temperature detecting means provided at the top when bathing is below the predetermined temperature, the chasing operation is stopped and the remaining hot water temperature detecting means at a predetermined position detects the predetermined temperature. The hot water supply apparatus according to claim 1, wherein a chasing operation is started. The accumulated flow rate detecting means is provided in the bath hot water filling circuit that joins the secondary side of the reheating heat exchanger, and when the necessary heat amount for reheating is obtained, the first arithmetic unit is used based on the amount of bath water detected by the accumulated flow rate detecting means. The hot water supply apparatus according to claim 1 or 2, wherein the calculation is performed as follows. The hot water supply apparatus according to any one of claims 1 to 4, wherein the hot water temperature by the heating means at the time of bathing is operated at a maximum setting. A time function and an accumulated time counter are provided, and the bath replenishment time of the past specific period detected by the accumulated time counter is reflected in the heating operation time performed in the night time zone of the next day. The hot water supply apparatus according to any one of the above.

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