JP2017194218A - Hot water storage type hot water supply device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hot water storage type hot water supply device which can recover heat of hot water in a bathtub, and which has high energy efficiency by avoiding wasteful drive of a bathtub pump.SOLUTION: A hot water storage type hot water supply device includes: a hot water storage tank; a circulation passage which connects an upper part and a lower part of the hot water storage tank, and which includes a circulation pump and a heat exchanger; and a bathtub circulation passage which connects a bathtub and the heat exchanger, and which includes a bathtub pump and bathtub temperature detection means. It also includes: heat recovery propriety determination means for determining whether or not to perform a heat recovery operation in which the heat in bathtub hot water is moved to the hot water in the hot water storage tank by comparing a bathtub temperature detected by the bathtub temperature detection means and a hot water temperature in the hot water storage tank by driving the bathtub pump when preset time comes; and bathtub pump drive determination means for determining whether or not to drive the bathtub pump before performing the determination by the heat recovery propriety determination means.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a hot water storage hot water supply apparatus that stores hot water heated by an external heat source machine in a hot water storage tank and can supply the stored hot water.

  Conventionally, hot water storage devices with high energy efficiency that can store hot water heated by an external heat source device such as a heat pump water heater and a fuel cell in a hot water storage tank and supply the stored hot water to a hot water supply destination have been widely used. In recent years, further reduction of energy consumption for hot water supply is expected. In particular, since hot water in a bathtub after bathing stores a large amount of heat energy, it is required to recover and use this heat energy.

  As such a hot water storage hot water supply device, a heat exchanger for heating the hot water in the bathtub using hot hot water stored in the upper side of the heat storage tank, and the heat of the hot water in the bathtub stored in the lower side of the heat storage tank Patent Document 1 discloses a hot water supply apparatus that includes a heat exchanger for heat recovery that recovers to low-temperature hot water that has been produced.

  However, since the hot water supply apparatus of Patent Document 1 has a heat exchanger for heating and a heat exchanger for heat recovery, the structure of the hot water supply apparatus becomes complicated. Therefore, the applicant of the present application uses a bath heat exchanger as a heat recovery heat exchanger, and relates to a hot water storage hot water supply apparatus that can recover hot water from a bathtub and use it for hot water supply with a simple structure. Have previously proposed (Japanese Patent Application No. 2015-248835).

JP 2009-192107 A

  The hot water storage hot water device proposed by the applicant of the present application has been determined not to be recovered because the temperature of the hot water in the bathtub is detected by driving the bathtub pump when determining whether the heat of the hot water in the bathtub is recoverable. In this case, the energy that drives the bathtub pump is wasted, and the energy efficiency of the hot water storage hot water supply apparatus may be reduced.

  An object of the present invention is to provide a hot water storage and hot water supply apparatus that can recover the heat of hot water in a bathtub and that has high energy efficiency by avoiding unnecessary driving of a bathtub pump.

  The hot water storage and hot water supply apparatus according to claim 1 connects a hot water storage tank, a circulation passage having a circulation pump and a heat exchanger connected to an upper part and a lower part of the hot water storage tank, a bathtub and the heat exchanger, and a bathtub pump. A hot water storage and hot water supply apparatus having a bathtub circulation passage provided with a bathtub temperature detection means, and when the set time comes, the bathtub temperature is detected by the bathtub temperature detection means by driving the bathtub pump, and in the hot water storage tank The heat recovery availability determination means for determining whether or not to perform the heat recovery operation for transferring the heat of the bathtub hot water to the hot water in the hot water storage tank by comparing the temperature of the hot water with the hot water temperature, and the determination by the heat recovery availability determination means And a bathtub pump drive determining means for determining whether or not to drive the bathtub pump before performing.

  According to a second aspect of the present invention, there is provided the hot water storage hot water supply apparatus according to the first aspect, wherein the bathtub pump drive determining means does not drive the bathtub pump when the temperature of the upper hot water in the hot water storage tank is higher than the set temperature of the bathtub by a predetermined temperature or more. It is characterized by judging.

  According to a third aspect of the present invention, there is provided the hot water storage hot water supply apparatus according to the first aspect, wherein the bathtub pump drive determining means determines that the bathtub pump is not driven when the elapsed time from the reheating operation of the bathtub is within a predetermined time. It is a feature.

  According to a fourth aspect of the present invention, there is provided a hot water storage and hot water supply apparatus according to the first aspect, wherein the hot water storage and hot water supply apparatus includes a time series prediction unit for the amount of hot water supply used, and the heat recovery possibility determination unit When hot water supply is not scheduled within a predetermined time, it is determined that the heat recovery operation is not performed.

  According to the invention of claim 1, since it is possible to recover the heat of the hot water in the bathtub and to determine whether or not to drive the bathtub pump before determining whether or not the heat recovery is possible, it is not necessary to detect the bathtub temperature. When it is clear that the recovery operation is not performed, the operation of the bathtub pump which is wasted can be avoided, and the energy consumption can be suppressed.

  According to the second aspect of the present invention, when hot water having a temperature higher than the bathtub set temperature by a predetermined temperature or more is stored in the hot water storage tank, the bathtub temperature is not higher than the bathtub set temperature. The hot water is in a state in which hot water can be formed by forming a temperature stratification, and if this temperature stratification is destroyed by the heat recovery operation, the energy efficiency is lowered, so the heat recovery operation is not performed. Therefore, it is not necessary to detect the temperature of the hot water in the bathtub, and the wasteful operation of the bathtub pump can be avoided to reduce energy consumption.

  According to the invention of claim 3, since there is a possibility that the user bathes after the bathing operation of the bathtub, the heat recovery operation for lowering the temperature of the hot water in the bathtub is not performed until a predetermined time has elapsed. Therefore, it is not necessary to detect the temperature of the hot water in the bathtub, and the wasteful operation of the bathtub pump can be avoided to reduce energy consumption.

  According to the invention of claim 4, since the heat recovery operation is not performed when the next hot water supply is not scheduled within a predetermined time, the temperature is lowered before the start of the hot water storage operation for the next hot water supply. Energy recovery can be suppressed by avoiding heat recovery operation.

It is a schematic block diagram of the hot water storage hot-water supply apparatus of this invention. It is a figure which shows the flow path of the hot water during heat recovery driving | operation. It is a flowchart of heat recovery operation control.

  Hereinafter, modes for carrying out the present invention will be described based on examples.

First, the hot water storage and hot water supply apparatus 1 of the present invention will be described.
As shown in FIG. 1, a hot water storage hot water supply apparatus 1 includes a hot water storage hot water supply unit 2 and an external heat source unit 3. The hot water storage hot water supply unit 2 includes an auxiliary heat source unit 4, a hot water storage tank 5, a heat exchanger 6, and a hot water storage tank 5 from the upper end of the hot water storage tank 5 via a circulation pump 7, the auxiliary heat source unit 4, and the heat exchanger 6. The circulation passage 8 connected to the lower end of the tub, the bathtub circulation passage 9 connecting the heat exchanger 6 and the bathtub 15, the heating circulation passage 10 connecting the hot water storage tank 5 and the external heat source unit 3, and various types of the hot water storage hot water supply apparatus 1 A control unit 11 for controlling the operation is provided.

Next, the hot water storage tank 5 and the circulation passage 8 will be described.
The hot water storage tank 5 is configured to be capable of storing hot water, and a plurality of hot water storage temperature sensors 5a to 5d are provided on the outer periphery in order from the bottom at different height positions to detect the temperature of the stored hot water. Note that the position and number of the hot water storage temperature sensors can be changed as appropriate according to the specifications of the hot water storage hot water supply apparatus 1 and the like. Moreover, although illustration is abbreviate | omitted, in order to prevent the temperature fall of the stored hot water, the circumference | surroundings of the hot water storage tank 5 are covered with the heat insulating material.

  The circulation passage 8 is connected to the upper end portion of the hot water storage tank 5 and the three-way valve 12 and is connected to the circulation passage portion 8a including the tank hot water temperature sensor 5f. A passage 8b, a circulation passage 8c connected to the auxiliary heat source 4 and the heat exchanger 6 and provided with a circulation temperature sensor 13, a heat exchanger 6 and the lower end of the hot water storage tank 5 connected to each other, a tank incoming water temperature sensor 5e, A circulation passage portion 8d having a heat exchanger electromagnetic valve 14 is provided.

  The tank hot water temperature sensor 5f is provided in the vicinity of the upstream end of the circulation passage portion 8a so that the temperature of hot water discharged from the hot water storage tank 5 and the temperature of hot water at the upper end of the hot water storage tank 5 can be detected. The tank incoming water temperature sensor 5e is provided in the vicinity of the downstream end of the circulation passage 8d so that the temperature of the hot water flowing into the hot water storage tank 5 and the temperature of the hot water at the lower end of the hot water storage tank 5 can be detected. The circulation temperature sensor 13 is provided on the downstream side of the circulation passage portion 8 c close to the heat exchanger 6 in order to detect the temperature of hot water flowing into the heat exchanger 6.

Next, the heat exchanger 6 and the bathtub circulation passage 9 will be described.
The heat exchanger 6 performs heat exchange between hot water flowing through the circulation passage 8 and hot water of the bathtub 15 flowing through the bathtub circulation passage 9 (hereinafter also referred to as bathtub hot water). The bathtub circulation passage 9 includes a forward passage portion 9a and a full return passage portion 9b. The bathing passage portion 9a includes a bathing temperature sensor 17a that detects the temperature of the bath water after heat exchange. The bath return passage portion 9 b includes a bathtub pump 16, a bath return temperature sensor 17 b, and a water level sensor 17 c that detects the water level of the bath 15. The bath return temperature sensor 17b corresponds to a bath temperature detecting means, and detects the temperature of the bath hot water flowing through the bath return passage portion 9b (hereinafter also referred to as bath temperature).

Next, the heating circulation passage 10 will be described.
The heating circulation passage 10 connects the lower part of the hot water storage tank 5 to the external heat source unit 3 and connects the upstream heating circulation passage part 10a provided with the heating circulation pump 18, and the upper part of the external heat source unit 3 and the hot water storage tank 5 to the heating circulation temperature. A downstream heating circulation passage portion 10b having a sensor 19 and a bypass passage portion 10c having a circulation switching valve 20 connected to the upstream heating circulation passage portion 10a and the downstream heating circulation passage portion 10b are provided. The hot water heated by the external heat source unit 3 is stored in the upper part of the hot water storage tank 5 by the circulation switching valve 20, and the hot water heated by the external heat source unit 3 is transferred to the external heat source unit 3 via the bypass passage 10c. The bypass passage side to be sent can be switched.

Next, the water supply passage 21 will be described.
The water supply passage 21 has an upstream end connected to a water supply source and a downstream end connected to the circulation passage portion 8 d to supply hot water to the hot water storage hot water supply unit 2. The water supply bypass passage 22 branches from the water supply passage 21 and is connected to the mixing valve 23. A water supply temperature sensor 24 and a check valve 25 are provided in the water supply passage 21, and a check valve 26 is provided in the water supply bypass passage 22. The high temperature hot water avoidance passage 28 connects the water supply bypass passage 22 and the hot water supply passage 27 and is provided so as to avoid high temperature hot water unexpected by the user.

Next, the tank hot water passage 29 will be described.
The tank discharge passage 29 is branched from the circulation passage portion 8 a and connected to the mixing valve 23. In the mixing valve 23, in order to supply hot water at a hot water supply set temperature set by the user to the hot water supply passage 27, low temperature clean water supplied from the water supply bypass passage 22 and high temperature hot water supplied from the tank hot water supply passage 29. The mixing ratio is adjusted.

Next, the hot water supply passage 27 will be described.
The hot water supply passage 27 includes a hot water supply temperature sensor 30 that can detect the hot water temperature adjusted by the mixing valve 23, and can supply hot water at a hot water supply set temperature to a hot water tap or the like. The hot water branch passage portion 27a branched from the hot water passage 27 and connected to the forward passage portion 9a is provided with an on-off valve 31 to supply hot water at a set temperature set by the user from the bathtub circulation passage 9 to the bathtub 15. Is possible.

Next, the auxiliary heat source unit 4 will be described.
The auxiliary heat source unit 4 is composed of a known gas water heater with a built-in burner, heat exchanger, and the like, and is capable of heating hot water flowing through the circulation passage portion 8b by performing a combustion operation in response to a command from the control unit 11. Hot water flowing out from the auxiliary heat source unit 4 flows through the circulation passage 8c. The downstream end of the auxiliary heating hot water passage 33 branched from the circulation passage portion 8 c and provided with the water proportional valve 32 is connected to the tank hot water passage 29.

  A circulation bypass passage 34 branched from the circulation passage portion 8d and connected to the three-way valve 12 is supplied from the water supply passage 21 by bypassing the hot water storage tank 5 by switching the three-way valve 12 from the circulation passage side to the circulation bypass passage side. Water or hot water flowing out from the heat exchanger 6 can be supplied to the auxiliary heat source unit 4.

  Hot water flowing out from the auxiliary heat source unit 4 can be supplied to a hot water tap or the like from the hot water supply passage 27 by opening the water proportional valve 32 and closing the heat exchanger electromagnetic valve 14, and closing the water proportional valve 32. By opening the heat exchanger solenoid valve 14, heat exchange with the bath water is possible in the heat exchanger 6.

Next, the external heat source unit 3 will be described.
The external heat source unit 3 is controlled by the control unit 11 via the auxiliary control unit 35, and the compressor 36, the condensation heat exchanger 37, the expansion valve 38, and the evaporating heat exchanger 39 are connected by the refrigerant pipe 40 to connect the heat pump circuit. This is a heat pump hot water supply apparatus configured to heat hot water using the heat of the refrigerant and the outside air enclosed in the refrigerant pipe 40. The external heat source unit 3 is not limited to a heat pump hot water supply device, and may be a hot water supply device that uses exhaust heat of a fuel cell.

Next, the operation remote controller 41 will be described.
The operation remote controller 41 displays an automatic bath heat recovery operation switch 41a (hereinafter also referred to as a heat recovery SW 41a) that can be operated by the user, other operation means (not shown), operation states, settings, and the like by characters, symbols, light emitting lamps, and the like. Possible display part. The set temperature and set time of various operations can be set by the operation of the operation remote controller 41 performed by the user, and data such as the set temperature is transmitted to the control unit 11.

Next, the control unit 11 will be described.
The control unit 11 receives data such as the temperature set by the operation of the operation remote controller 41 provided in the bathroom or the like, acquires data such as the temperature detected by various sensors such as the hot water storage temperature sensors 5a to 5d, Hot water storage operation, hot water operation, reheating operation, heat recovery operation, etc. so that the circulation pump 7 and the three-way valve 12 are driven and the external heat source device 3 and the auxiliary heat source device 4 are operated to supply hot water at a set temperature. To control. In addition, the control unit 11 is configured to accumulate and learn time series data of actual hot water supply, and to be able to predict time series of future hot water usage, and corresponds to time series prediction means for hot water usage.

Next, hot water storage operation will be described.
The control unit 11 operates the external heat source unit 3 based on the time series prediction of the amount of hot water used, switches the circulation switching valve 20 to the hot water storage tank side, drives the heating circulation pump 18, and starts low temperature from the lower part of the hot water storage tank 5. Hot water is supplied to the external heat source unit 3, and hot water having a set temperature of hot water heated by the external heat source unit 3 is stored in the upper part of the hot water storage tank 5. The flow rate of the hot water flowing through the heating circulation passage 10 is controlled so as to be heated to the hot water storage set temperature by the external heat source unit 3 based on the outside air temperature, the temperature of the hot water in the lower part of the hot water storage tank 5 and the like.

  By continuing the hot water storage operation, the hot water layer of the hot water set temperature stored in the upper part of the hot water storage tank 5 expands downward, and the low temperature hot water layer shrinks. The control unit 11 can detect the amount of hot water at the hot water storage set temperature stored in the hot water storage tank 5 based on the temperatures detected by the hot water storage temperature sensors 5 a to 5 d provided in the hot water storage tank 5.

Next, hot water filling operation will be described.
When the user instructs the hot water filling operation from the operation remote controller 41, the hot water filling operation is started based on the bathtub set temperature, the set hot water amount or the like preset by the user, and the on-off valve 31 is opened. The filling operation may be started or completed at the time set by the user. The hot water of the hot water set temperature stored in the hot water storage tank 5 by the hot water storage operation flows into the mixing valve 23 from the tank hot water outlet passage 29 by the supply water pressure. The control unit 11 adjusts the mixing valve 23 to supply hot water of a bathtub set temperature to the hot water supply passage 27, and supplies the set hot water amount from the hot water supply passage 27 to the bathtub 15 via the branch passage portion 27 a and the bathtub circulation passage 9. .

Next, the chasing operation will be described.
When the user instructs the reheating operation from the operation remote controller 41, the reheating operation is started based on the bathtub set temperature or the like. The control unit 11 closes the water proportional valve 32, opens the heat exchanger solenoid valve 14, switches the three-way valve 12 to the circulation bypass passage 34 side, drives the circulation pump 7, and operates the auxiliary heat source unit 4. The hot water heated by the auxiliary heat source unit 4 flows into the heat exchanger 6 through the circulation passage portion 8c.

  In parallel with this, the control unit 11 drives the bathtub pump 16 in the bathtub circulation passage 9 to circulate bathtub hot water. Heat is exchanged between the hot water heated by the auxiliary heat source unit 4 and the bathtub hot water in the heat exchanger 6 to heat the bathtub hot water. finish. You may make it maintain a bathtub preset temperature automatically.

Next, the heat recovery operation will be described.
As shown in FIG. 2, the heat recovery operation is performed in the heat exchanger 6 by exchanging heat between hot water in the hot water storage tank 5 circulating in the circulation passage 8 and hot water in the bathtub circulating in the bathtub circulation passage 9. The heat is recovered in the hot water in the hot water storage tank 5. The heat recovery operation control by the control unit 11 at this time will be described based on the flowchart shown in FIG. In the flowchart, Si (i = 1, 2,...) Represents each step. Further, the user can make a reservation by designating a time (hereinafter referred to as a set time) for starting the heat recovery operation from the operation remote controller 41. The set time is preferably set to a time zone when bathing is over and no hot water is used.

  First, in S1, it is determined whether or not the user has reserved a heat recovery operation. For example, it is determined whether or not the heat recovery SW 41a of the operation remote controller 41 is ON. While the heat recovery SW 41a is ON, the operation remote controller 41 displays that the heat recovery operation is reserved. If the determination is Yes, the process proceeds to S2. If the determination is No, the process returns to S1.

  Next, in S2, it is determined whether or not the current time is the set time for the heat recovery operation. If the determination is Yes, the process proceeds to S3, and if the determination is No, the process returns to S1.

Next, in S3, in order to extract the case where it is necessary to detect the bathtub temperature for determining whether or not the heat recovery operation is possible, it is determined whether or not the bathtub pump driving condition A is satisfied. The bathtub pump driving condition A is, for example, the following conditions A1 to A3.
(A1) Since the detection temperature of the hot water storage temperature sensor 5d is not higher than the bath set temperature by a predetermined temperature or more, hot water that can be discharged is not stored.
(A2) The detected water level of the water level sensor 17c is a water level at which the bathtub hot water can be circulated in the bathtub circulation passage 9.
(A3) Since the elapsed time after the latest driving operation in the hot water filling operation or the chasing operation to the bathtub 15 is within 12 hours, the drop in the bathtub temperature is slight.
If all the conditions of A1 to A3 are satisfied and the determination of S3 is Yes, the process proceeds to S4, and if the determination is No, the process returns to S1. In addition, the predetermined temperature of the condition A1 can be appropriately set in consideration of the predicted temperature drop until the next tapping, and can be set to 0 ° C. Further, the bathtub pump driving condition A may not include a safety operation that should be prioritized and other operations that are not disturbed.

  Next, in S4, it is determined whether or not the bathtub pump driving condition B is satisfied so that the heat recovery operation is not started at a time far from the set time. For example, it is determined whether the elapsed time from the set time is within one hour. If the determination is Yes, the process proceeds to S5, and if the determination is No, the process returns to S1.

Next, in S5, it is determined whether or not the bathtub pump driving condition C is satisfied in order not to prevent the user from using hot water. The bathtub pump driving condition C is, for example, the following conditions C1 and C2.
(C1) The elapsed time during hot water supply or after the end of the latest hot water supply is not within 10 minutes.
(C2) The elapsed time after the completion of the latest bathtub reheating operation is not within a predetermined time.
If both the conditions of C1 and C2 are satisfied and the determination of S5 is Yes, the process proceeds to S6, and if the determination is No, the process returns to S3. Note that the predetermined time of the condition C2 is a time at which the end of bathing after the chasing operation is expected, and may be, for example, 1 hour, or may be set appropriately by the user. S3-S5 demonstrated above is corresponded to a bathtub pump drive determination means.

  Next, in S6, the bathtub pump 16 is driven to circulate bathtub hot water in the bathtub circulation passage 9 at a flow rate of 5 L / min, for example, and the process proceeds to S7. At this time, it may be displayed on the operation remote controller 41 that the bath heat recovery operation is being performed.

  Next, in S7, it is determined whether or not the heat recovery operation start condition D is satisfied in order to determine whether or not the heat recovery operation is possible. For example, the bathtub temperature detected by the bath return temperature sensor 17 within one minute from the start of driving of the bathtub pump 16 in S6 is based on the average temperature of hot water stored in the hot water storage tank 5 (hereinafter referred to as the tank average temperature). It is determined whether or not a temperature higher than 15 ° C. has been detected for 1 second. If the determination is Yes, that is, if it is determined that the heat recovery operation is possible, the process proceeds to S8, and if the determination is No, the process proceeds to S13 to stop the bathtub pump 16 and returns to S1. Here, the tank average temperature is calculated from the temperatures detected by the hot water storage temperature sensors 5a to 5d and the tank incoming water temperature sensor 5e and the amount of hot water corresponding to the height positions of these temperature sensors. This S7 corresponds to a heat recovery possibility determination unit.

  Next, in S8, the heat recovery operation is started. For example, the tank water proportional valve 32 is closed, the three-way valve 12 is switched to the circulation passage side, the heat exchanger solenoid valve 14 is opened, and the circulation pump 7 is driven so that the circulation flow rate becomes 5 L / min. The hot water stored in the tank 5 is circulated through the circulation passage 8. Circulation of the bathtub hot water is started in the bathtub circulation passage 9 in S6, and the process proceeds to S9 while transferring heat from the bathtub hot water to the hot water stored in the hot water storage tank 5 in the heat exchanger 6. While the heat recovery operation is timed during the heat recovery operation, if the heat recovery operation is resumed after the heat recovery operation is interrupted in the next S9, the heat recovery time is restarted from the interrupted time.

  Next, in S9, it is determined whether or not the heat recovery operation standby condition E is satisfied. For example, it is determined whether an operation other than the heat recovery operation such as a hot water supply operation has been started. When the determination is Yes, that is, when another operation is started, the heat recovery operation is interrupted and the time measurement of the heat recovery time is interrupted. If the operation remote controller 41 has a display indicating that the bath heat recovery operation is in progress, this display is terminated and another operation is executed (S14). When the other operation is completed, the process returns to S3. At this time, if the determination is No, the process proceeds to S10.

Next, in S10, it is determined whether or not the heat recovery operation end condition F is satisfied. The heat recovery operation end condition F is, for example, the following conditions F1 and F2.
(F1) The measured heat recovery time reached 1.5 hours.
(F2) The temperature difference between the bath temperature and the tank average temperature is 5 ° C. or less.
If any one of the conditions of F1 and F2 is satisfied, that is, if the determination in S10 is Yes, the process proceeds to S11, and if the determination is No, the process returns to S9. Note that conditions for giving priority to safe operation and other operations may be included in the heat recovery operation end condition F.

  Next, in S11, the heat recovery operation is terminated. The circulation pump 7 and the bathtub pump 16 are stopped, the three-way valve 12 and the tank water proportional valve 32 are driven to a predetermined standby position, the heat exchanger electromagnetic valve 14 is closed, and the measured heat recovery time is set to zero. If there is a display on the operation remote controller 41 during the bath heat recovery operation, the display is terminated and the process proceeds to S12.

  Next, in S12, it is determined whether or not the heat recovery end condition G is satisfied so that the heat recovery operation is not performed at a time far from the set time. For example, it is determined whether the elapsed time from the set time is 1 hour or longer. If the determination is Yes, the process returns to S1, and if the determination is No, the process returns to S3. It is assumed that the heat recovery operation control described above continues to operate while the hot water storage hot water supply device 1 is operable.

Next, the operation and effect of the hot water storage hot water supply apparatus 1 of the present invention will be described.
The hot water storage and hot water supply apparatus 1 determines whether or not a part of the heat stored in the hot water in the bathtub 15 can be recovered, and performs heat recovery operation if it can be recovered. This heat recovery possibility determination is performed based on the tank average temperature and the bathtub temperature detected by driving the bathtub pump 16, and determines whether the bathtub pump 16 can be driven before the heat recovery permission determination. When it is clear that the heat recovery operation is not performed without detecting the temperature of hot water in the bathtub, for example, when hot water that can be discharged into the hot water storage tank 5 is stored, or hot water that can be recovered in the bathtub 15 If not, the drive of the bathtub pump 16 is avoided to prevent wasted energy consumption, so that a decrease in energy efficiency can be avoided.

An example in which the embodiment is partially changed will be described.
[1] Based on the time series prediction of the amount of hot water used, the heat recovery operation is not performed when the next hot water supply is not scheduled within a predetermined time, for example, within 24 hours. With such a configuration, it is possible to avoid a heat recovery operation that is wasted by cooling down to the start of the hot water storage operation for the next hot water supply, and therefore, wasteful energy consumption is avoided and the energy of the hot water storage hot water supply device 1 is avoided. A decrease in efficiency can be prevented.
[2] When another operation is started during the heat recovery operation, the heat recovery operation may be terminated.
[3] In addition, those skilled in the art can implement the present invention in various forms with various modifications without departing from the spirit of the present invention, and the present invention includes such modifications. It is.

DESCRIPTION OF SYMBOLS 1 Hot water storage hot water supply device 5 Hot water storage tank 5a-5d Hot water storage temperature sensor 5e Tank incoming water temperature sensor 6 Heat exchanger 7 Circulation pump 8 Circulation passage 9 Bath circulation passage 11 Control unit (Time series prediction means of hot water use amount)
14 heat exchanger solenoid valve 15 bathtub 16 bathtub pump 17b bath return temperature sensor (tub temperature detection means)
17c Water level sensor 41 Operation remote control 41a Automatic bath heat recovery operation switch (heat recovery SW)

Claims (4)

A hot water storage tank, a circulation passage having a circulation pump and a heat exchanger connected to the upper and lower portions of the hot water storage tank, a bathtub having a bathtub pump and a bathtub temperature detection means connected to the bathtub and the heat exchanger A hot water storage and hot water supply device having a circulation passage,
When the set time is reached, the bathtub pump is driven to compare the bathtub temperature detected by the bathtub temperature detecting means with the hot water temperature in the hot water storage tank, thereby converting the hot water in the hot water into the hot water in the hot water storage tank. Heat recovery possibility determination means for determining whether to perform the heat recovery operation to be moved; and
A hot water storage and hot water supply apparatus comprising: a bathtub pump drive determination unit that determines whether or not to drive the bathtub pump before the determination by the heat recovery possibility determination unit.   The bathtub pump drive determining means determines that the bathtub pump is not driven when the temperature of the upper hot water in the hot water storage tank is higher than a set temperature by a predetermined temperature or more. Hot water storage water heater.   2. The hot water storage and hot water supply apparatus according to claim 1, wherein the bathtub pump drive determining means determines that the bathtub pump is not driven when the elapsed time from the reheating operation of the bathtub is within a predetermined time. The hot water storage hot water supply device includes a time series prediction means of hot water supply usage,
The heat recovery possibility determination means determines that the heat recovery operation is not performed when the next hot water supply is not scheduled within a predetermined time based on the prediction of the time series prediction means. The hot water storage hot water supply device described in 1.