WO2019030900A1

WO2019030900A1 - Hot water supply device

Info

Publication number: WO2019030900A1
Application number: PCT/JP2017/029133
Authority: WO
Inventors: 赳弘古谷野; 啓輔 ▲高▼山
Original assignee: 三菱電機株式会社
Priority date: 2017-08-10
Filing date: 2017-08-10
Publication date: 2019-02-14
Also published as: EP3667195B1; EP3667195A4; EP3667195A1; JP6921203B2; JPWO2019030900A1

Abstract

This hot water supply device comprises: a hot water storage tank that stores hot water; a heat exchanger that exchanges heat between hot water in the hot water storage tank and hot water in a bathtub; a bathtub circulation route by which hot water discharged from the bathtub is returned to the bathtub via the heat exchanger; a bathtub circulation pump that is provided in the bathtub circulation route and that circulates hot water in the bathtub to the bathtub circulation route; and a control device that implements a heat collection operation to collect the heat from the hot water in the bathtub into the hot water in the hot water storage tank and a cleaning operation to clean the inside of the bathtub. In both the heat collection operation and the cleaning operation, the bathtub circulation pump is driven and the hot water in the bathtub circulates in the bathtub circulation route.

Description

Water heater

The present invention relates to a hot water supply apparatus for supplying hot and cold water to a bath.

BACKGROUND ART In recent years, as hot-water supply devices have become more sophisticated, hot-water supply devices that not only generate hot water but also adjust the hot-water supply temperature to an appropriate temperature and fill the bath with an appropriate amount of water are known. In addition, a hot water supply device is also known that uses hot water in the bathtub to be transported to the hot water supply device using a pump and exchanges heat with the hot water generated by the hot water supply device to repel hot water in the bathtub.

Furthermore, Patent Document 1 proposes a hot water supply device that achieves energy saving by heat exchange between hot water in a bath and hot water in a hot water storage tank provided in a hot water supply device, and recovering heat of hot water in the bath. ing. In addition, Patent Document 2 proposes a hot water supply device that cleans the inside of the bathtub by heating the hot and cold water in the bathtub and generating fine bubbles to circulate the inside of the bathtub.

Patent No. 5126432 JP, 2016-48130, A

Here, in order to improve energy saving performance and convenience, a water heater capable of performing both heat recovery and bath cleaning is desired. However, when both heat recovery and bath cleaning are performed, with the increase of functions, the number of parts and the size of the apparatus may be increased, and the product cost may be increased.

This invention is made in view of the said situation, and it aims at providing the hot-water supply apparatus which can implement both heat recovery and bathtub cleaning, suppressing the increase in product cost.

A water heater according to the present invention comprises a hot water storage tank for storing hot water, a heat exchanger for exchanging heat between hot water in the hot water storage tank and hot water in the bathtub, and hot water flowing out of the bathtub through the heat exchanger A tub circulation pump provided in the tub circulation path for returning and a tub circulation path, for circulating hot water in the tub to the tub circulation path, heat recovery operation for recovering heat of hot water in the tub to hot water in the hot water storage tank, And a controller for performing a cleaning operation for cleaning the inside of the bathtub, and in both the heat recovery operation and the cleaning operation, the bathtub circulation pump is driven, and hot and cold water in the bathtub circulates in the bathtub circulation path.

According to the water heater according to the present invention, in both the heat recovery operation and the cleaning operation, the bathtub circulation pump is driven, and hot and cold water in the bathtub is circulated in the bathtub circulation path. Thus, by using a common configuration in the heat recovery operation and the cleaning operation, both heat recovery and bath cleaning are performed while suppressing an increase in the product cost due to an increase in the number of parts and an increase in size of the device. Can.

FIG. 1 is a schematic configuration diagram of a hot water supply apparatus according to Embodiment 1. It is a figure which shows the hardware constitutions of a control apparatus. It is a functional block diagram of a control device. It is a figure which shows the flow of the hot and cold water at the time of heat recovery driving | operation. It is a figure which shows the flow of the hot and cold water at the time of washing | cleaning operation. 5 is a flowchart showing a flow of heat recovery operation and cleaning operation according to the first embodiment. 7 is a flowchart showing the flow of a heat recovery operation and a cleaning operation in Embodiment 2. FIG. FIG. 16 is a flow chart showing the flow of heat recovery operation and cleaning operation in the third embodiment. FIG.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In each of the drawings used in the present specification, the same reference numeral is attached to a common element. Moreover, in this specification, "hot water" is a general term for warm water (hot water) and water.

Embodiment 1
FIG. 1 is a schematic block diagram of a hot water supply apparatus 100 according to Embodiment 1 of the present invention. Hot water supply apparatus 100 according to the present embodiment heats low-temperature water supplied from water supply end 101, and supplies hot water with a temperature desired by the user from hot water supply end 102. The hot water supply end 102 is, for example, a water inlet of a bath tub 200, a faucet or a shower head, or a faucet of a washroom or a cooking area.

Hot water supply apparatus 100 performs heat exchange between the heat pump unit 110 heating low temperature water, the hot water storage tank 120 storing high temperature water heated by the heat pump unit 110, and the hot water in the hot water storage tank 120 and the hot water in the bathtub 200 And an exchange unit 130. Further, the hot water supply apparatus 100 returns the hot and cold water flowing out of the bathtub 200 to the bathtub 200 via the heat exchanger 130 and the hot water and water flowing out of the hot water storage tank 120 via the heat exchanger 130. And a tank circulation path 150 for returning to the hot water storage tank 120. Furthermore, the hot water supply apparatus 100 includes a control device 160 that controls the operation of the entire hot water supply apparatus 100, and a remote controller 170. Although not essential in the present invention, the hot water supply apparatus 100 further supplies a boiling path for circulating hot water in the hot water storage tank 120 via the heat pump unit 110 and hot water supplying the hot water in the hot water storage tank 120 to the bathtub 200. It has a path and three-way valves, an on-off valve, a check valve, etc. provided in each path.

The heat pump unit 110 is a refrigeration cycle apparatus using, for example, CO ₂ or HFC (hydrofluorocarbon) as a refrigerant. The heat pump unit 110 includes a compressor, a first heat exchanger that exchanges heat between a refrigerant and water, an expansion valve, a second heat exchanger that exchanges heat between the outside air and the refrigerant, a blower, a temperature sensor, And a control board etc. The compressor, the first heat exchanger, the expansion valve, and the second heat exchanger are annularly connected to form a refrigeration cycle circuit (also referred to as a refrigerant circuit) for circulating the refrigerant.

The hot water storage tank 120 is a cylindrical tank formed of metal such as stainless steel or resin. A heat insulating material (not shown) is disposed outside the hot water storage tank 120. Thereby, high temperature water can be kept warm for a long time in the hot water storage tank 120. The lower part of the hot water storage tank 120 is connected to the water supply end 101 via a pipe provided with a pressure reducing valve 103. The low temperature water supplied from the water supply end 101 is adjusted to a predetermined pressure by the pressure reducing valve 103 and flows into the hot water storage tank 120. Moreover, the lower part and upper part of the hot water storage tank 120 are connected to the heat pump unit 110 via a heating up path. Thereby, the low temperature water which flowed out from the lower part of hot water storage tank 120 is heat-exchanged with the 1st heat exchanger of heat pump unit 110, becomes high temperature water, and is returned to the upper part of hot water storage tank 120. Such circulation forms a boiling circuit. Further, in the hot water storage tank 120, a temperature stratification in which the temperature of the hot water is higher toward the upper side in the vertical direction and the temperature of the hot water is lower on the lower side is formed.

Further, on the surface of the hot water storage tank 120, a plurality of hot water

storage temperature sensors

121 and 122 are attached at different heights. The hot water

storage temperature sensors

121 and 122 detect the temperature distribution of hot and cold water in the hot water storage tank 120. The detection results of the hot water

storage temperature sensors

121 and 122 are transmitted to the control device 160, and the control device 160 grasps the amount of hot water storage in the hot water storage tank 120, and is used to control the start and stop of the boiling operation described later. In addition, the number of stored water temperature sensors is not limited to two, and three or more may be provided.

The heat exchanger 130 exchanges heat between the hot water in the bathtub 200 and the hot water in the hot water storage tank 120. More specifically, the heat exchanger 130 is provided on the bath circulation path 140 and the tank circulation path 150, and performs heat exchange between the hot water flowing through the bath circulation path 140 and the hot water flowing through the tank circulation path 150.

The bathtub circulation path 140 is a pipe that connects the hot water supply device 100 and the bathtub 200. The bathtub circulation path 140 includes a bathtub return pipe 141 and a bathtub forward pipe 142. In addition, a bathtub circulation pump 145 for circulating hot and cold water in the bathtub is provided on the bathtub circulation path 140. By driving the bathtub circulation pump 145, hot and cold water can be circulated between the hot water supply apparatus 100 and the bathtub 200. Specifically, by driving the bathtub circulation pump 145, the hot and cold water in the bathtub 200 flows into the hot water supply apparatus 100 via the bathtub return pipe 141, and again from the hot water supply apparatus 100 via the bathtub forward pipe 142 Return to 200.

Moreover, the addition device 148 which adds an additive to the hot and cold water in the bathtub 200 at the time of washing | cleaning operation is provided in the bathtub forward piping 142. As shown in FIG. The adding device 148 adds the additive to the hot water in the bath 200 in accordance with the control signal from the controller 160. As the additive, one having a surfactant effect is used. Thus, by circulating hot and cold water containing an additive in the bath 200 during the washing operation, the washing effect of the bath 200 can be enhanced.

The tank circulation path 150 is a pipe that connects the lower portion and the middle portion of the hot water storage tank 120 via the heat exchanger 130. In the tank circulation path 150, a tank circulation pump 155 for conveying the hot and cold water of the hot water storage tank 120 to the heat exchanger 130 is provided. Further, a three-way valve 151, a first four-way valve 152, and a second four-way valve 153 are provided in the tank circulation path 150. By switching the three-way valve 151, the first four-way valve 152, and the second four-way valve 153, the hot water / water circulation path of the hot water storage tank 120 is switched.

The bathtub circulation pump 145 and the tank circulation pump 155 are provided with an inverter circuit (not shown) and are driven according to control signals transmitted from the controller 160. By changing the driving rotational speeds of the bathtub circulation pump 145 and the tank circulation pump 155, the amount of hot and cold water flowing to the bathtub circulation path 140 and the tank circulation path 150 can be changed.

Control device 160 is communicably connected to each part of water heating apparatus 100. Control device 160 controls each part of water heating apparatus 100 in accordance with a user operation on remote controller 170. Specifically, the control device 160 controls the operation of the heat pump unit 110, the bathtub circulation pump 145, the tank circulation pump 155 and the addition device 148, and the switching of the three-way valve 151, the first four-way valve 152 and the second four-way valve 153 Do. Further, control device 160 causes remote controller 170 to display the operation state of hot water supply device 100 and the operation screen and the like. Details of the control device 160 will be described later.

Remote controller 170 includes a display unit that displays an operation state of water heating apparatus 100 and the like, and an operation unit that receives a user's operation on water heating apparatus 100. The operation unit includes a bathtub cleaning switch 171 instructing the start of the cleaning operation. The operation on the remote controller 170 is sent to the controller 160.

Next, the configuration of control device 160 of water heating apparatus 100 will be described in detail. FIG. 2 is a diagram showing a hardware configuration of the control device 160. As shown in FIG. As shown in FIG. 2, the control device 160 includes a central processing unit (CPU) 601, a communication interface 602, a read only memory (ROM) 603, a random access memory (RAM) 604, and a secondary storage device 605. Equipped with The CPU 601, the communication interface 602, the ROM 603, the RAM 604, and the secondary storage device 605 are mutually connected via a bus 606. The CPU 601 centrally controls the control device 160. Details of the functions implemented by the CPU 601 will be described later.

The communication interface 602 includes a NIC (Network Interface Card controller) for performing wired communication or wireless communication. The communication interface 602 is communicably connected to the remote controller 170, the heat pump unit 110, the bathtub circulation pump 145, the tank circulation pump 155, and the adding device 148. Control device 160 receives a user's operation on remote controller 170 via communication interface 602, and transmits a control signal to each part of the hot water supply device via communication interface 602.

The ROM 603 stores a plurality of firmware or data used when executing these firmware. A RAM 604 is used as a work area of the CPU 601.

The secondary storage device 605 is composed of a read / write non-volatile semiconductor memory or a hard disk drive such as an EEPROM (Electrically Erasable Programmable Read-Only Memory) or a flash memory. The secondary storage device 605 stores a program for controlling the operation of the hot water supply apparatus 100, data used when executing these programs, and the like. The data used when the program is executed includes various parameters used to control each operation mode of water heating apparatus 100, data indicating control of bathtub circulation pump 145 and tank circulation pump 155, and the like.

FIG. 3 is a functional block diagram of control device 160. As shown in FIG. As illustrated in FIG. 3, the control device 160 includes, as functional units, a user interface unit 611, an apparatus state acquisition unit 612, an apparatus control unit 613, and an operation mode execution unit 614. Each of these functional units is realized by the CPU 601 executing one or a plurality of programs stored in the secondary storage device 605.

The user interface unit 611 performs user interface processing via the remote controller 170. That is, the user interface unit 611 receives a user operation on the remote controller 170. In addition, the user interface unit 611 transmits information (for example, information indicating the operating state of the hot water supply apparatus 100) to be presented to the user to the remote controller 170, and causes the remote controller 170 to display the information.

The device state acquisition unit 612 acquires data such as the operating state and the measured temperature from the heat pump unit 110 every fixed time, for example, 30 seconds, and acquires data indicating the operating state from the bathtub circulation pump 145 and the tank circulation pump 155 Do. The device state acquisition unit 612 also acquires the temperature of the hot and cold water in the hot water storage tank 120 from the hot water

storage temperature sensors

121 and 122.

Device control unit 613 controls the overall operation of water heating apparatus 100 in accordance with a user operation via remote controller 170. Specifically, the device control unit 613 transmits a control signal to the heat pump unit 110 to control the compressor, the expansion valve, the blower, and the like. The device control unit 613 also transmits control signals to the bathtub circulation pump 145, the tank circulation pump 155, and the addition device 148 in heat recovery operation and cleaning operation to control operation and stop. Furthermore, the device control unit 613 transmits control signals to the three-way valve 151, the first four-way valve 152, and the second four-way valve 153 to switch the flow path.

The operation mode execution unit 614 causes the device control unit 613 to execute control corresponding to the operation mode selected by the user operation via the remote controller 170. Specifically, the operation mode execution unit 614 reads the control of the heat pump unit 110 corresponding to the selected operation mode or the bathtub circulation pump 145 and the tank circulation pump 155 from the secondary storage device 605 and executes the control to the device control unit 613. Let The operation mode to be selected includes a boiling operation, a heat recovery operation and a bathtub cleaning operation.

Subsequently, a heat recovery operation and a cleaning operation in water heating apparatus 100 of the present embodiment will be described. The heat recovery operation is an operation for the water heater 100 to recover the heat of the hot and cold water in the bathtub 200, and the washing operation is an operation for washing the bathtub 200.

<Heat recovery operation>
First, the heat recovery operation by the hot water supply apparatus 100 of the present embodiment will be described. FIG. 4 is a diagram showing the flow of hot and cold water during the heat recovery operation. In the heat recovery operation, both the bathtub circulation pump 145 and the tank circulation pump 155 are driven, and hot water flows in both the bathtub circulation path 140 and the tank circulation path 150. First, the flow of hot and cold water in the bathtub 200 will be described. The hot and cold water from the bathtub 200 passes through the bathtub return pipe 141, is pressurized by the bathtub circulation pump 145, and is sent to the heat exchanger 130. Then, the hot and cold water flowing out of the heat exchanger 130 returns to the bathtub 200 again through the bathtub forward piping 142.

Subsequently, the flow of hot and cold water in the hot water storage tank 120 will be described. Hot and cold water flowing out of the lower portion of the hot water storage tank 120 passes through the three-way valve 151 and is pressurized by the tank circulation pump 155. The hot and cold water pressurized by the tank circulation pump 155 flows from the first four-way valve 152 to the second four-way valve 153 and flows into the heat exchanger 130. The hot and cold water flowing out of the heat exchanger 130 flows into the hot water storage tank 120 from the center of the hot water storage tank 120. When the three-way valve 151, the first four-way valve 152, and the second four-way valve 153 are open in one particular direction, they are not open in the other direction. At the time of heat recovery operation, the three-way valve 151, so that hot and cold water flows in the order of the hot water storage tank 120, the three-way valve 151, the tank circulation pump 155, the first four-way valve 152, the second four-way valve 153, the heat exchanger 130, and the hot water storage tank 120. The first four-way valve 152 and the second four-way valve 153 are switched.

In the heat exchanger 130, the hot water in the bathtub 200 and the hot water in the hot water storage tank 120 exchange heat. Thereby, when the temperature of the hot and cold water in the bathtub 200 is higher than the temperature of the hot and cold water in the lower portion of the hot water storage tank 120, the heat of the hot and cold water in the bathtub 200 can be recovered to the hot and cold water in the hot water storage tank 120.

<Washing operation>
Subsequently, the cleaning operation by the hot water supply apparatus 100 of the present embodiment will be described. FIG. 5 is a diagram showing the flow of hot and cold water during the cleaning operation. In the washing operation, the bathtub circulation pump 145 is driven, and hot and cold water flows through the bathtub circulation path 140. The hot and cold water from the bathtub 200 passes through the bathtub return pipe 141, is pressurized by the bathtub circulation pump 145, and is sent to the heat exchanger 130. Then, the hot and cold water flowing out of the heat exchanger 130 returns to the bathtub 200 again via the bathtub forward piping 142. By circulating the hot and cold water in this manner, the bath 200 can be cleaned by the water flow generated in the bath 200. In addition, when the cleaning operation is performed, the additive is added to the hot water in the bathtub 200 from the adding device 148. Thereby, the hot water containing an additive circulates the inside of the bathtub 200, and the cleaning effect of the bathtub 200 can be heightened.

In addition, since the heat exchange between the hot water in the bathtub 200 and the hot water in the hot water storage tank 120 is not necessary during the cleaning operation, the tank circulation pump 155 is not driven. Therefore, the hot and cold water in the hot water storage tank 120 does not circulate in the tank circulation path 150.

As described above, the hot water supply apparatus 100 according to the present embodiment can perform both the heat recovery operation and the cleaning operation. Also, the bathtub circulation pump 145 and the bathtub circulation path 140 are used in both the heat recovery operation and the washing operation. Thus, by using a common configuration in the heat recovery operation and the cleaning operation, it is not necessary to provide a circulation path and a circulation pump for each operation. Thereby, both the heat recovery operation and the cleaning operation can be performed while suppressing an increase in the number of parts of the hot water supply apparatus 100 and an increase in size of the apparatus and an increase in product cost associated therewith. Further, by using a common configuration in the heat recovery operation and the cleaning operation, complication of control can be prevented, and the heat recovery operation and the cleaning operation can be efficiently performed.

Here, when using a common configuration for heat recovery operation and cleaning operation as in the present embodiment, the heat recovery operation and the cleaning operation may interfere with each other depending on the usage form of the user, and the operation may be optimized. There is no fear. Therefore, the hot water supply apparatus 100 according to the present embodiment achieves appropriate operation by automatically controlling the timing of performing the heat recovery operation and the cleaning operation.

FIG. 6 is a flowchart showing the flow of the heat recovery operation and the cleaning operation in the present embodiment. The flowchart of FIG. 6 is realized by the CPU 601 executing one or more programs stored in the secondary storage device 605. First, it is determined whether the start of the cleaning operation has been instructed (S11). Here, it is determined that the start of the cleaning operation has been instructed by the operation of the bathtub cleaning switch 171 of the remote controller 170. When the start of the cleaning operation is instructed (S11: YES), the device control unit 613 causes the three-way valve 151, the first four-way valve 152, and the second four-way valve to flow the hot and cold water of the hot water storage tank 120 through the tank circulation path 150. The flow path of the valve 153 is switched (S12). Then, in accordance with the control signal from the device control unit 613, the additive is added from the adding device 148 to the hot water in the bathtub 200 (S13).

Then, the bathtub circulation pump 145 and the tank circulation pump 155 are driven by the device control unit 613 (S14). Thereby, the hot and cold water in the bathtub 200 circulates in the bathtub circulation path 140, and the hot and cold water in the hot water storage tank 120 circulates in the tank circulation path 150. At this time, in the heat exchanger 130, heat exchange between the hot water in the bathtub 200 and the hot water in the hot water storage tank 120 is performed. Thereby, the heat of the hot and cold water in the bathtub 200 is recovered to the hot and cold water in the hot water storage tank 120, and the heat recovery operation is performed. Further, the hot water with the additive added is circulated in the bath circulation path 140 and the bath 200, whereby the washing operation is performed.

Then, when the predetermined time T has elapsed (S15: YES), the bathtub circulation pump 145 and the tank circulation pump 155 are stopped by the device control unit 613 (S16), and the heat recovery operation and the cleaning operation end. The predetermined time T is preset and stored in the secondary storage device 605. Alternatively, the predetermined time T may be arbitrarily set by the user, or may be variable according to the device state acquired by the device state acquisition unit 612.

As described above, in the present embodiment, the heat recovery operation and the cleaning operation are simultaneously performed according to the operation of one switch, that is, the bathtub cleaning switch 171. Thereby, as compared with the case where each operation is performed separately, simplification of operation and shortening of the operating time of bathtub circulation pump 145 can be realized. As a result, the operation can be optimized, and the reduction of power consumption can be realized.

Further, when the additive is added to the hot water in the bath 200, the flow path resistance of the bath circulation path 140 is reduced due to the surface active effect of the additive. Thereby, the input of the bathtub circulation pump 145 can be suppressed at the same circulation flow rate as compared with the case where the heat recovery operation is performed alone. Therefore, a heat recovery operation with high energy saving is possible as compared to the case where the heat recovery operation is performed alone.

In addition, the timing which stops the bathtub circulation pump 145 and the tank circulation pump 155 is not limited after progress of predetermined time T. For example, when the temperature of the hot and cold water in the bathtub 200 becomes lower than a predetermined temperature (for example, 30 ° C.), the bathtub circulation pump 145 and the tank circulation pump 155 may be stopped. Alternatively, when there is no difference between the temperature of hot and cold water in the bathtub 200 and the temperature of hot and cold water stored in the lower part of the hot water storage tank 120 detected by the hot water storage temperature sensor 122, the bathtub circulation pump 145 and the tank circulation pump 155 You may stop it. Furthermore, instead of stopping the bath circulation pump 145 and the tank circulation pump 155 simultaneously, one of the bath circulation pump 145 and the tank circulation pump 155 may be stopped earlier than the other.

Second Embodiment
Next, a second embodiment of the present invention will be described. The present embodiment is different from the first embodiment in the timing of performing the heat recovery operation and the cleaning operation. The configuration of water heating apparatus 100 and the flow of hot and cold water during heat recovery operation and bathtub cleaning are the same as in the first embodiment.

FIG. 7 is a flowchart showing the flow of the heat recovery operation and the cleaning operation in the present embodiment. In the present embodiment, the heat recovery operation is started after the start of the cleaning operation. First, it is determined whether the start of the cleaning operation has been instructed (S21). Here, as in the first embodiment, it is determined that the start of the cleaning operation has been instructed by operating the bathtub cleaning switch 171 of the remote controller 170. When the start of the cleaning operation is instructed (S21: YES), a control signal is transmitted from the device control unit 613 to the addition device 148, and the additive is added to the hot water in the bathtub 200 from the addition device 148 (S22) . Then, the bathtub circulation pump 145 is driven by the device control unit 613 (S23). Thus, the washing operation is performed by the hot water containing the additive circulating in the bath circulation path 140 and the bath 200.

Then, a predetermined time to _{T 1} is elapsed (S24: NO), the cleaning operation is continued. When the predetermined time _{T 1} is elapsed (S24: YES), hot water of the hot water storage tank 120 to flow through tank circulation path 150, the device control section 613, the three-way valve 151, the first four-way valve 152 and the second four-way valve The 153 flow paths are switched (S25). Then, the tank circulation pump 155 is driven by the device control unit 613 (S 26), and the hot and cold water in the hot water storage tank 120 circulates in the tank circulation path 150. Thereby, in the heat exchanger 130, heat exchange between the hot water in the bathtub 200 and the hot water in the hot water storage tank 120 is performed, and a heat recovery operation is performed.

Then, a predetermined time to _{T 2} has elapsed (S27: NO), the cleaning operation and the heat recovery operation is continued. When the predetermined time _{T 2} has elapsed (S27: YES), the device control unit 613, tub circulation pump 145 and the tank circulation pump 155 is stopped (S28), heat recovery operation and cleaning operation is completed.

As described above, in the present embodiment, the cleaning operation and the heat recovery operation are continuously performed according to the operation of one switch. During the cleaning operation, the higher the temperature of the hot and cold water in the bathtub 200, the higher the cleaning effect. Moreover, the temperature of the hot and cold water in the bathtub 200 falls by implementing a heat recovery operation. Therefore, by performing the heat recovery operation after starting the cleaning operation as in the present embodiment, the water temperature during cleaning can be kept high, and a high cleaning effect can be expected.

The timing of driving the tank circulating pump 155, after driving the bath circulation pump 145, is not limited to after the predetermined time T ₁ is passed. For example, the timing for driving the tank circulation pump 155 may be determined based on the temperature of hot water stored in the hot water storage tank 120 or the bathtub 200. Specifically, the temperature of the hot water stored in the bathtub 200 is 35 ° C. or lower, or the temperature difference between the hot water stored in the bathtub 200 and the hot water stored in the lower part of the hot water storage tank 120 is within 5 ° C. Alternatively, the tank circulation pump 155 may be driven to start the heat recovery operation. Thereby, in the heat recovery operation, the minimum amount of heat recovery can be secured. Also, instead of stopping the bath circulation pump 145 and the tank circulation pump 155 simultaneously, one of the bath circulation pump 145 and the tank circulation pump 155 may be stopped earlier than the other.

Third Embodiment
Next, a third embodiment of the present invention will be described. The present embodiment is different from the first embodiment in the timing of performing the heat recovery operation and the cleaning operation. The configuration of water heating apparatus 100 and the flow of hot and cold water during heat recovery operation and bathtub cleaning are the same as in the first embodiment.

FIG. 8 is a flowchart showing the flow of the heat recovery operation and the cleaning operation in the present embodiment. In the present embodiment, the cleaning operation is carried out after the start of the heat recovery operation. First, it is determined whether the start of the cleaning operation has been instructed (S31). Here, as in the first embodiment, it is determined that the start of the cleaning operation has been instructed by pressing the bathtub cleaning switch 171 of the remote controller 170. When the start of the cleaning operation is instructed (S31: YES), the device control unit 613 controls the three-way valve 151, the first four-way valve 152, and the second so that the hot and cold water of the hot water storage tank 120 flows through the tank circulation path 150. The flow path of the four-way valve 153 is switched (S32).

Then, the bathtub circulation pump 145 and the tank circulation pump 155 are driven by the device control unit 613 (S33). Thereby, the hot and cold water in the bathtub 200 circulates in the bathtub circulation path 140, and the hot and cold water in the hot water storage tank 120 circulates in the tank circulation path 150. Then, in the heat exchanger 130, heat exchange between the hot water in the bathtub 200 and the hot water in the hot water storage tank 120 is performed, and a heat recovery operation is performed.

Then, until a predetermined time _{T 3} has elapsed (S34: NO), the heat recovery operation is continued. When the predetermined time _{T 3} has elapsed (S34: YES), the transmission control signal is added 148 from the device control unit 613, additives are added from the addition unit 148 to the hot water in the bathtub 200 (S35) . At this time, the hot and cold water in the bathtub 200 has already circulated in the bathtub circulation path 140, but the addition of the additive starts the washing operation with a high washing effect.

Then, if the predetermined time _{T 4} has elapsed (S36: YES), the tank circulation pump 155 is stopped (S37), the heat recovery operation is completed. When the further predetermined time _{T 5} has elapsed (S38: YES), bath circulation pump 145 is stopped (S39), the cleaning operation is completed.

As described above, in the present embodiment, the heat recovery operation and the cleaning operation are continuously performed by operating one switch. Depending on the type of additive added to the bath 200, the heat transfer performance of the heat exchanger 130 may be impaired. In this case, even when the heat recovery operation is performed in a state where the additive is added to the inside of the bath 200, a high heat recovery effect can not be expected. Therefore, by performing the cleaning operation after starting the heat recovery operation as in the present embodiment, the heat transfer performance deterioration of the heat exchanger 130 during heat recovery is suppressed, and a high energy saving effect can be expected.

The timing of adding the additive after driving the bath circulation pump 145 and the tank circulation pump 155, is not limited to after the lapse of a predetermined time T _3. The temperature of the hot water stored in the hot water storage tank 120 or the bathtub 200 may determine the timing of adding the additive. Specifically, when the temperature of the hot and cold water stored in the bathtub 200 becomes lower than a predetermined temperature (for example, 35 ° C.), an additive may be added to secure the cleaning effect. Alternatively, when the temperature difference between the hot water stored in the bathtub 200 and the hot water stored in the lower part of the hot water storage tank 120 is within 2 ° C., no further heat recovery effect can be expected, and even if an additive is added Good.

Further, after the additive is added to the bath 200, a configuration for stopping the tank circulation pump 155 when a predetermined time T ₄ has elapsed, but the invention is not limited thereto. For example, the stop timing of the tank circulation pump 155 may be determined based on the temperature of hot water stored in the hot water storage tank 120 or the bathtub 200 or the power consumption of the tank circulation pump 155. For example, when the temperature difference between the hot water stored in the bathtub 200 and the hot water stored in the lower part of the hot water storage tank 120 is within 2 ° C., no further heat recovery effect can be expected, and the tank circulation pump 155 is stopped. The heat recovery operation may be ended. Alternatively, when the power reduced by the amount of heat recovery led from the temperature of the hot water stored in the bathtub 200 and the temperature of the hot water stored under the hot water storage tank 120 is smaller than the power consumption of the tank circulation pump 155, The circulation pump 155 may be stopped to end the heat recovery operation.

The present invention is not limited to the above embodiment, and various modifications and applications can be made without departing from the scope of the present invention. For example, although the water heating apparatus 100 according to the first to third embodiments is a heat pump water heating apparatus using the heat pump unit 110 as a heat source machine, an electric heater or gas combustion may be used as a heat source instead of the heat pump unit 110.

Further, in the first to third embodiments, it is determined that the start of the cleaning operation is instructed by pressing the bathtub cleaning switch 171 of the remote controller 170, and the cleaning operation and the heat recovery operation are performed simultaneously or continuously. Although it was set as a structure, it is not limited to this. For example, the remote controller 170 is provided with both the bathtub cleaning switch 171 and the bathtub heat recovery switch (not shown), and when either switch is pressed, the cleaning operation and the heat recovery operation are performed simultaneously or continuously. You may implement. Also, the bathtub cleaning switch 171 and the bathtub heat recovery switch (not shown) are not limited to physical switches, but may be instructions by software key or voice. Further, the remote controller 170 of the hot water supply apparatus 100 is not an essential component, and the control device 160 may be configured to be communicable with an external terminal other than the remote controller 170. Then, the start instruction of the cleaning operation may be transmitted from the external terminal. Furthermore, the instruction for the cleaning operation or the heat recovery operation is not limited to the instruction from the user, and is automatically instructed by the operation mode execution unit 614 based on the schedule information and the like stored in the secondary storage device 605. It may be

Moreover, the addition apparatus 148 of the hot-water supply apparatus 100 is not also an essential structure, and the additive may be thrown in in the bathtub 200 by the user. As an example of the cleaning method of the bathtub 200 using the hot water supply apparatus 100 in this case, the user first adds the additive to the hot and cold water in the bathtub 200, and then operates the bathtub cleaning switch 171 to perform heat recovery operation and cleaning operation May be implemented simultaneously. Alternatively, the washing operation may be performed without the addition of additives. Also, instead of the addition device 148, a device that generates air bubbles that enhances the cleaning effect may be provided. Also in this case, bubbles are generated in the hot and cold water in the bathtub 200 according to the control signal of the control device 160 as in the addition device 148.

DESCRIPTION OF SYMBOLS 100 water heater, 101 water supply end, 102 hot water supply end, 103 pressure-reduction valve, 110 heat pump unit, 120 hot water storage tank, 121, 122 hot water storage temperature sensor, 130 heat exchanger, 140 bathtub circulation path, 141 bathtub return piping, 142 bathtub going piping , 145 bathtub circulation pump, 148 addition device, 150 tank circulation path, 151 three-way valve, 152 first four-way valve, 153 second four-way valve, 155 tank circulation pump, 160 controller, 170 remote controller, 171 bathtub washing switch, 200 Bathtub, 601 CPU, 602 communication interface, 603 ROM, 604 RAM, 605 secondary storage device, 606 bus, 611 user interface unit, 612 device state acquisition unit, 613 device control unit, 614 Rolling mode execution unit.

Claims

Hot water storage tank for storing hot water,
A heat exchanger for exchanging heat between the hot water in the hot water storage tank and the hot water in the bath;
A bathtub circulation path for returning hot water flowing out of the bathtub to the bathtub via the heat exchanger;
A bathtub circulation pump provided in the bathtub circulation path and circulating hot and cold water in the bathtub to the bathtub circulation path;
The heat recovery operation for recovering the heat of the hot and cold water in the bath to the hot and cold water in the hot water storage tank, and the control device for performing the cleaning operation for cleaning the inside of the bath.
The hot water supply apparatus in which the bathtub circulation pump is driven in both the heat recovery operation and the cleaning operation, and hot and cold water in the bathtub circulates in the bathtub circulation path.
The hot water supply device according to claim 1, wherein the control device performs both the heat recovery operation and the cleaning operation according to the operation of one switch.
The hot water supply device according to claim 1 or 2, wherein the control device simultaneously performs the heat recovery operation and the cleaning operation, or continuously performs the heat recovery operation and the cleaning operation.
The hot water supply apparatus according to claim 3, wherein the control device performs the heat recovery operation continuously after the cleaning operation.
The control device is configured such that, when a predetermined time has elapsed after the start of the cleaning operation, the temperature of the hot and cold water in the bathtub becomes lower than or equal to the predetermined temperature, or the hot water and cold water in the bathtub and the lower portion of the hot water storage tank The hot water supply apparatus according to claim 4, wherein the heat recovery operation is started when the temperature difference between the stored hot water and the hot water becomes equal to or less than a predetermined temperature.
The hot water supply apparatus according to claim 3, wherein the control device performs the cleaning operation continuously after the heat recovery operation.
The control device is configured such that, when a predetermined time has elapsed after the heat recovery operation is started, the temperature of the hot water in the bathtub becomes lower than the predetermined temperature, or the hot water in the bathtub and the lower portion of the hot water storage tank The hot water supply apparatus according to claim 6, wherein the cleaning operation is started when the temperature difference between the hot water stored in the water supply tank and the hot water supply water is equal to or less than a predetermined temperature.
A tank circulation path for returning hot water flowing out of the hot water storage tank to the hot water storage tank via the heat exchanger;
And a tank circulation pump provided in the tank circulation path for circulating hot and cold water in the hot water storage tank to the tank circulation path.
When a predetermined time has passed after the start of the cleaning operation, the control device determines that the temperature difference between the hot water in the bathtub and the hot water stored in the lower part of the hot water storage tank is equal to or lower than a predetermined temperature. Alternatively, if the power reduced by the amount of heat recovery led from the temperature of the hot water in the bath and the temperature of the hot water stored in the lower part of the hot water storage tank is smaller than the power consumption of the tank circulation pump, the heat recovery The hot water supply apparatus according to claim 7, which ends the operation.
A tank circulation path for returning hot water flowing out of the hot water storage tank to the hot water storage tank via the heat exchanger;
And a tank circulation pump provided in the tank circulation path for circulating hot and cold water in the hot water storage tank to the tank circulation path.
The control device drives the tank circulation pump and the bathtub circulation pump in the heat recovery operation, and drives the bathtub circulation pump and does not drive the tank circulation pump in the cleaning operation. The hot water supply apparatus according to any one of the items.
The hot water supply device according to any one of claims 1 to 9, further comprising an addition device that adds an additive that enhances the cleaning effect to the hot and cold water in the bath during the cleaning operation.
The hot water supply device according to claim 10, wherein the additive has a surfactant effect.
It is a cleaning method of the bathtub using the hot water supply device according to claim 1,
Adding an additive for enhancing the cleaning effect to the hot and cold water in the bath;
And d) simultaneously performing the heat recovery operation and the cleaning operation.