Bath equipment

Abstract

To provide a bath device that includes a heat-pump water heater in addition to an instant water heater and improves energy efficiency when a bathtub is filled with hot water while having a compact device size.SOLUTION: A bath heading flow passage R9a and a bath return flow passage R9b which are determined by a water flow direction of a bath pump P1 and connect an instant water heater and a bathtub B are provided in the instant water heater, and a hot water heating unit HEX1 of a heat-pump water heater HP is provided in least at one of the bath heading flow passage R9a and the bath return flow passage R9b. Operation control means 50 operates a bath pump P1, which serves as additional heating means, and the heat-pump water heater HP after filling the bathtub B with hot water by hot water supply means and then stops the combustion of the instant water heater and performs additional heating of the bathtub B, thus performing high-efficiency hot water filling as a hot water filling operation so that a hot water filling state of the bathtub B reaches a target hot water filling state.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a bath device that includes a heat pump water heater, an instantaneous water heater that uses gas or oil as fuel, a hot water supply means that supplies hot water to a bathtub, a reheating heating means that heats the hot water in the bathtub, and an operation control means that operates at least one of the hot water supply means and the reheating heating means to perform a water filling operation that fills the bathtub with water so that the bathtub reaches a target water filling state. [Background technology]

[0002] BACKGROUND ART Conventionally, a bath device is known that includes an instantaneous water heater that uses gas or oil as fuel, and also includes a heat pump water heater that heats water (see Patent Document 1). When the bath device performs the filling operation, hot water heated by the instantaneous water heater and hot water heated by the heat pump water heater are mixed in the mixing section, and hot water at the target filling temperature is supplied to the bathtub. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2000-111154 Summary of the Invention [Problem to be solved by the invention]

[0004] In the bath device according to Patent Document 1, a separate mixing section for mixing hot and cold water is required, and it is not easy to add a heat pump water heater to a bath device equipped only with an instantaneous water heater based on the configuration disclosed in Patent Document 1. Furthermore, there was no disclosure or suggestion regarding the control of efficient operation of the heat pump water heater in relation to filling and reheating the bath, and there was room for improvement.

[0005] The purpose of this application to solve the above problem is to provide a bath device that adds a heat pump water heater to a bath device equipped with an instantaneous water heater, thereby making the device more compact while improving energy efficiency when filling the bathtub with water. [Means for solving the problem]

[0006] To achieve the above object, the bath device is A bath device is provided with a heat pump water heater, an instantaneous water heater that uses gas or oil as fuel, a hot water supply means that supplies hot water to a bathtub, a reheating heating means that heats the hot water in the bathtub, and an operation control means that operates at least one of the hot water supply means and the reheating heating means to fill the bathtub with water so that the bathtub reaches a target filling state, and its characteristic configuration is as follows: The instantaneous water heater has a built-in bath pump and is provided with a bath supply flow path and a bath return flow path that connect the instantaneous water heater and the bathtub, and the bath pump's water flow direction is determined by the bath pump's water flow direction. At least one of the bath supply flow path and the bath return flow path is provided with a hot water heating unit of the heat pump water heater, The operation control means operates the bath pump and the heat pump water heater, which are the reheating heating means, after filling the bathtub with water using the hot water supply means, and stops the combustion of the instantaneous water heater to reheat the bathtub, thereby performing a highly efficient water filling operation as the water filling operation so that the water filling state of the bathtub reaches the target water filling state.

[0007] According to the above characteristic configuration, a configuration is adopted in which the hot water heating section of a heat pump water heater is provided in at least one of the bath supply flow path and the bath return flow path, so that a heat pump water heater can be easily added later to a bath system that only has an instantaneous water heater. Furthermore, according to the above characteristic configuration, in a configuration in which a heat pump water heater is added to a bath device that only has an instantaneous water heater (e.g., a boiler), when filling the bathtub with water, after filling the bathtub with water, the bath pump and heat pump water heater, which are the reheating heating means, are activated, the combustion of the instantaneous water heater is stopped to reheat the bathtub, and the bathtub is controlled so that the bathtub is filled to the target water filling state.This allows the bathtub to be filled with water by operating only the energy-efficient heat pump water heater, thereby improving the energy efficiency of the filling operation. In particular, with this configuration, when filling a bathtub with water using a heat pump water heater, which has a heating capacity per unit time significantly lower than that of an instantaneous water heater, a large hot water storage tank is not required as in conventional technology, and the device can be made smaller, making it easier to install in apartment buildings and other places where installation space is limited.

[0008] As a result of the above, by adding a heat pump water heater to a bathtub system equipped with an instantaneous water heater, it is possible to realize a bathtub system that can be made smaller while also improving energy efficiency when filling the bathtub with water.

[0009] Further characteristic configurations of the bath device include: The operation control means, after filling the bathtub with water using the hot water supply means, operates the bath pump and heat pump water heater, which are the reheating heating means, as a first-stage filling process, and stops the combustion of the instantaneous water heater to reheat the bathtub, and operates the combustion of the bath pump and instantaneous water heater, which are the reheating heating means, as a second-stage filling process, to reheat the bathtub, thereby performing the high-efficiency filling operation so that the bathtub's water filling state reaches the target water filling state.

[0010] When the combustion of an instantaneous water heater, which has a high heating capacity per unit time, is stopped and only a heat pump water heater, which has a low heating capacity per unit time, is operated to perform the water filling operation, it takes longer than when the water filling operation is performed using only the instantaneous water heater. Therefore, when only the heat pump water heater is operated as the water filling operation, in situations where a user needs to take a bath suddenly, the user may be forced to wait a long time, which may impair the user's experience. According to the above-mentioned characteristic configuration, the highly efficient filling operation involves two steps: first-stage filling, which activates the bath pump and heat pump water heater (both of which are reheating heating means) and stops the combustion of the instantaneous water heater to reheat the bathtub; and second-stage filling, which activates the combustion of the bath pump and instantaneous water heater (both of which are reheating heating means) and reheats the bathtub, in the order described above.By adjusting the timing of the second-stage filling, the water can be heated in time for the scheduled boiling time.This allows for a filling operation that improves energy efficiency while not compromising the user's experience.

[0011] Further characteristic configurations of the bath device include: The heat pump water heater is provided with a first flow rate adjustment valve that can adjust the flow rate of hot and cold water introduced to the hot and cold water heating section.

[0012] Generally, heat pump water heaters have a lower heating capacity per unit time than instantaneous water heaters, and tend to be able to supply less heat to hot water per unit time. However, by providing a first flow control valve that can adjust the flow rate of hot water led to the hot water heating section of the heat pump water heater, as in the above characteristic configuration, the flow rate of hot water led to the heat pump water heater can be adjusted to an appropriate flow rate according to the output of the heat pump water heater by adjusting the flow rate of hot water with the first flow control valve, thereby realizing heating of hot water according to the heating capacity of the heat pump water heater and further improving energy savings.

[0013] The bath equipment we have explained so far is as follows: It is preferable that a first thermometer be provided between the hot water heating unit of the heat pump water heater and the bathtub, for measuring the temperature of the hot water being led from the hot water heating unit to the bathtub. In particular, it is preferable that the operation control means has a characteristic configuration in which, when operating the heat pump water heater in the high-efficiency water filling operation, the bath pump built into the instantaneous water heater and at least one of a first flow control valve capable of adjusting the flow rate of hot water led to the hot water heating section of the heat pump water heater adjust the temperature of the hot water measured by the first thermometer to a target reheating temperature, which is a temperature higher than the target water filling temperature for the target water filling state.

[0014] According to the above characteristic configuration, regardless of where the hot water heating section of the heat pump water heater is installed (added) in the bath supply flow path or the bath return flow path, the temperature of the hot water led from the hot water heating section of the heat pump water heater to the bathtub is measured by the first thermometer, and the bath pump or the first flow control valve is controlled so that the measured hot water temperature becomes the target reheating temperature, which is a temperature higher than the target hot water filling temperature for the target hot water filling state, thereby allowing high-efficiency hot water filling operation to be performed appropriately.

[0015] Further characteristic configurations of the bath device include: A bath return thermometer is provided to measure the temperature of the hot water flowing from the bathtub to the bath return flow path, The operation control means switches from the first-stage filling process to the second-stage filling process when the time from the current time to the predetermined scheduled boiling time is less than a predetermined time set based on the execution time of the second-stage filling process, and the bath return temperature measured by the bath return thermometer is less than the target filling temperature for the target filling state.

[0016] According to the above characteristic configuration, if the time from the current time to the scheduled boiling time is less than a predetermined time (for example, less than 10 minutes) set based on the execution time of the second half filling process, and the bath return temperature measured by the bath return thermometer is less than the target filling temperature for the target boiling state, and the first half filling process, which only performs heating using a heat pump water heater, is unable to boil the water in time for the scheduled boiling time, the system can switch from the first half filling process to the second half filling process using combustion by an instantaneous water heater, thereby quickly raising the temperature of the water in the bathtub to the target filling temperature and completing the boiling in time for the scheduled boiling time. [Brief explanation of the drawings]

[0017] [Figure 1] A figure showing the state of hot water flow when water filling is being performed in a high-efficiency water filling operation in a bath device according to an embodiment. [Figure 2] 10 is a diagram showing the flow of hot water when a high-efficiency water filling operation is being performed in which only the heat pump water heater is operating in the bath device of the embodiment. FIG. [Figure 3] A diagram showing the hot water flow state when the bath device of the embodiment is performing a hot water filling operation using only an instantaneous water heater. [Figure 4] This figure shows the hot water flow state when performing a high-efficiency water filling operation related to the second half water filling process in which only the instantaneous water heater is operated in the bath device of the embodiment. [Figure 5] FIG. 10 is a diagram showing the flow of hot water when a high-efficiency water filling operation is being performed in a bath device according to another embodiment, in which only the heat pump water heater is operating. [Figure 6] FIG. 10 is a control flow diagram for a high-efficiency water filling operation in which only the heat pump water heater is operated in the bath device according to the embodiment. [Figure 7] A control flow diagram for highly efficient bath filling operation including a first half bath filling process and a second half bath filling process in a bath device according to another embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0018] The bath device 100 of an embodiment of the present invention is configured by adding a heat pump water heater to a bath device equipped with an instantaneous water heater, thereby providing a bath device that can be made smaller while also improving energy efficiency when filling the bathtub with water. Hereinafter, a bath apparatus 100 according to an embodiment will be described with reference to FIGS.

[0019] <Embodiment> As shown in Figures 1 to 3 and 6, the bath apparatus 100 of the embodiment is provided with a heat pump water heater HP, a gas or oil-fueled combustion device 12 (part of an instantaneous water heater), a hot water supply means for supplying hot water to a bathtub B, a reheating heating means for heating the hot water in the bathtub B, and a control device 50 (an example of an operation control means) that operates at least one of the hot water supply means and the reheating heating means to perform a water filling operation to fill the bathtub B with water so that the water filling state of the bathtub B reaches a target water filling state. Incidentally, in FIGS. 1 to 4, the valve body in the open state is shown painted black, and the valve body in the closed state is shown painted white. The bath apparatus 100 according to this embodiment does not have a hot water tank for storing hot water.

[0020] The combustion device 12 (part of an instantaneous water heater) is configured as a two-can, two-channel type, and is configured to burn gas fuel (e.g., city gas 13A) in a first burner 11a provided inside, thereby heating hot water flowing through a first heat exchange section 12a inside, and to burn gas fuel in a second burner 11b provided inside, thereby heating hot water flowing through a second heat exchange section 12b inside. To further explain, a reheating circulation path C2 is provided which is connected to the second heat exchange section 12b of the combustion device 12, and the reheating circulation path C2 is provided with, in the order listed, a second circulation pump P2 which circulates hot water through the reheating circulation path C2, a second heat exchange section 12b of the combustion device 12 which exchanges heat in a countercurrent manner with the hot water stored in the bathtub B during reheating operation (or during high-efficiency filling operation as described below) based on the second circulation pump P2 in the direction in which the hot water is pumped by the second circulation pump P2, a third opening / closing valve K3 which opens and closes the reheating circulation path C2, and a buffer tank BT.

[0021] The water supply passage R1 that supplies water is connected to a heating passage R4 that passes hot water through the first heat exchange section 12a of the combustion device 12, and the heating passage R4 is provided with a fourth temperature sensor T4 that detects the post-heating temperature at the outlet of the combustion device 12. In this specification, hot water is a concept that includes both hot water after heating and water supplied before heating. The connection point between the water supply flow path R1 and the heating flow path R4 is connected to the upstream end of the post-heating mixing flow path R5, and is equipped with a second three-way valve S2 that can adjust the flow rate ratio of hot and cold water to the heating flow path R4 and the post-heating mixing flow path R5, and the downstream end of the post-heating mixing flow path R5 is connected to a second confluence G2 downstream of the fourth temperature sensor T4 of the heating flow path R4. The second junction G2 has a hot water supply flow path R7 connected to the hot water supply usage point 1, and a third temperature sensor T3 that measures the mixed temperature after heating is provided near the connection point of the hot water supply flow path R7 to the second junction G2, and a second flow rate sensor F2 that can detect whether hot water is flowing through the hot water supply flow path R7 is provided near the hot water supply usage point 1 of the hot water supply flow path R7. A hot water filling line R8 that leads hot water to bathtub B is connected downstream of the third temperature sensor T3 on the hot water supply line R7. The hot water filling line R8 is equipped with a first flow rate sensor F1 that can detect whether hot water is flowing through the hot water filling line R8, and a second flow rate adjustment valve V2 that can adjust the flow rate of hot water flowing through the hot water filling line R8. The second flow rate adjustment valve V2 is built into the housing (not shown) of the instantaneous hot water heater. The hot water filling line R8 is connected to a first pressure pump P1 that is provided in the reheating line R9 (described later), and the hot water from the hot water filling line R8 is led to bathtub B via the reheating line R9.

[0022] Furthermore, a reheating flow path R9 is provided, which consists of a bath supply flow path R9a and a bath return flow path R9b that connect the first heat exchanger EX1 of the instantaneous water heater to the bathtub B, and is determined by the water flow direction of the first pressure pump P1 (an example of a bath pump) built into the housing of the instantaneous water heater. To further explain, the reheating flow path R9 consists of a bath return flow path R9b, whose upstream end is connected to the lower part of bathtub B, and a bath supply flow path R9a, whose downstream end is connected to the upper part of bathtub B, in the direction of hot water flow during reheating operation.The reheating flow path R9 is equipped with, from upstream, a fourth on-off valve K4 that opens and closes the bath return flow path R9b, a seventh temperature sensor T7 (an example of a bath return thermometer) that measures the temperature of hot water flowing from bathtub B into the reheating flow path R9, a first pressure pump P1 that pressurizes hot water through the reheating flow path R9, a third flow sensor F3 that detects whether hot water is flowing through the reheating flow path R9, a first heat exchanger EX1 of the instantaneous water heater, a sixth temperature sensor T6 that measures the temperature of hot water flowing from the reheating flow path R9 to bathtub B, and a third three-way valve S3 that can branch hot water from the reheating flow path R9 to the branch flow path R10 described below.

[0023] In the bath device 100 of this embodiment, hot water can be heated not only by the instantaneous water heater but also by the heat pump water heater HP during the reheating operation of the bathtub B and the high-efficiency water filling operation described below. The heat pump water heater HP includes a refrigerant circulation path C3 for circulating a refrigerant, a compressor HPP for compressing the refrigerant circulating through the refrigerant circulation path C3, a condenser HEX1 (an example of a hot water heating section of a heat pump water heater) for exchanging heat between the refrigerant compressed by the compressor HPP and hot water, an expansion valve HV for expanding the refrigerant condensed by the condenser HEX1, and an evaporator HEX2 for evaporating the refrigerant expanded by the expansion valve HV. The reheating flow path R9 (bathroom supply flow path R9a) is provided with a branch flow path R10 whose upstream end is connected to the upstream side of the flow path between the sixth temperature sensor T6 and the bathtub B and whose downstream end is connected to the downstream side, and the branch flow path R10 is provided with a first flow control valve V1 that controls the flow rate of hot water flowing through the branch flow path R10 from the upstream side, a condenser HEX1 of the heat pump water heater HP, and an eighth temperature sensor T8 (an example of a first thermometer) that measures the temperature of the hot water flowing through the outlet of the condenser HEX1, in the order listed. Furthermore, at the upstream end of the branch flow path R10, a third three-way valve S3 is provided which switches between a first flow state (flow state shown in Figures 1, 3, and 4) in which the hot water is led directly to the bathtub B without passing through the branch flow path R10, and a second flow state (flow state shown in Figure 2) in which the hot water is led to the bathtub B after being led to the heat pump water heater HP side via the branch flow path R10.

[0024] In the configuration described so far, the first flow sensor F1, the second flow control valve V2, the first flow control valve V1, the second three-way valve S2, the third three-way valve S3, the water supply flow path R1, the heating flow path R4, the post-heating mixing flow path R5, the hot water filling flow path R8, the branch flow path R10, the first temperature sensor T1, the third temperature sensor T3, the fourth temperature sensor T4, the sixth temperature sensor T6, and the instantaneous water heater or the heat pump water heater HP function as hot water supply means. In addition, the third flow sensor F3, the third on-off valve K3, the fourth on-off valve K4, the third three-way valve S3, the first flow control valve V1, the second circulation pump P2, the first pressure discharge pump P1, the first heat exchanger EX1, the buffer tank BT, the reheating circulation path C2, the reheating path R9, the sixth temperature sensor T6, the seventh temperature sensor T7, the eighth temperature sensor T8, and either or both of the instantaneous water heater and the heat pump water heater HP will function as the reheating heating means.

[0025] The control device 50 (an example of an operation control means) equipped with a computer that controls the operation of the bath device 100 is configured to be able to communicate various information with a manually operated hot water supply device remote control (not shown) that commands operation. The hot water supply device remote control is installed, for example, in the kitchen or bathroom, and is capable of setting the target hot water supply temperature, the target hot water filling temperature in the target hot water filling state, the target hot water reheating temperature in the reheating operation, etc., and is configured to be able to request various operations by turning on various switches. The control device 50 is also configured to be able to communicate various information with a manually operated bath remote control (not shown) that commands the filling operation of bathtub B, etc. Incidentally, the bath remote control is configured to be able to set a high-efficiency hot water filling operation, which is a highly energy-efficient operation, in addition to the normal hot water filling operation (filling operation using only the instantaneous hot water heater, described below).

[0026] The control device 50 is put into a controllable state when the operation switch on the remote control is turned on, and when the hot water supply point 1 is opened, the control device 50 executes a hot water supply operation to supply hot water to the hot water supply point 1. In addition, when the bath remote control's water filling switch is turned ON to request water filling, the control device 50 performs normal water filling operation, and when the bath remote control's water reheating switch is turned ON to request water reheating, the control device 50 performs normal water reheating operation to reheat the water stored in bathtub B. The above-mentioned high-efficiency water filling operation takes longer from start to finish than normal water filling operation, so when eco operation is set and a scheduled water boiling time is set, the control device 50 executes the high-efficiency water filling operation so that water filling is completed at the scheduled water boiling time. Each operation will be explained below.

[0027] (Hot water operation) Although the flow of hot water and water is not shown in the figure, the hot water supply operation is an operation that is performed when water flow is detected by the second flow rate sensor F2, and the control device 50 controls the opening and closing of the second three-way valve S2 so that the post-heating mixed temperature measured by the third temperature sensor T3 becomes the hot water supply target temperature set in the hot water supply operation.

[0028] During hot water supply operation, the control device 50 sets the second three-way valve S2 to an open state, allowing hot water to flow through both the heating flow path R4 and the post-heating mixing flow path R5 at a predetermined ratio, and heats the water in the combustion device 12 before supplying it to the hot water supply location 1.

[0029] (Normal filling operation) When performing normal filling operation (filling operation using only the instantaneous water heater), the control device 50 stops the heat pump water heater HP, activates the combustion of the instantaneous water heater, switches the third three-way valve S3 to the first flow state (the flow state shown in Figure 3), and opens the fourth on-off valve K4, as shown in Figure 3. Incidentally, during filling operation using only the instantaneous water heater, hot water is guided to the bathtub B via the first pressure delivery pump P1, flowing through both the bath supply flow path R9a and the bath return flow path R9b, which serve as the reheating flow path R9. To further explain, when filling operation is performed using only the instantaneous water heater, the control device 50 controls the opening and closing of the second three-way valve S2, the third three-way valve S3, and the fourth opening and closing valve K4 so that the post-heating mixed temperature measured by the third temperature sensor T3 becomes the target filling temperature set for the filling operation, and also controls the opening of the second flow control valve V2 to a predetermined opening degree. More specifically, so that the post-heating mixing temperature measured by the third temperature sensor T3 becomes the target filling temperature set for the water filling operation, the second three-way valve S2 is set to an open state that allows hot water to flow through both the heating flow path R4 and the post-heating mixing flow path R5 at a predetermined ratio, the third three-way valve S3 is set to an open state that allows hot water to flow through the bath supply flow path R9a but not through the branch flow path R10, the fourth on-off valve K4 is set to an open state, and the second flow adjustment valve V2 is controlled to a predetermined opening. In other words, during water filling operation using only the instantaneous water heater, the heat pump water heater HP is stopped. The normal water filling operation is carried out at a predetermined time set in advance by a remote control (not shown), or when a water filling request is made from the remote control.

[0030] (High-efficiency filling operation) After filling bathtub B with water using the hot water supply means, control device 50 activates the first pressure pump P1 and heat pump water heater HP, which are the reheating heating means, and stops combustion in the instantaneous water heater to reheat bathtub B, thereby performing a high-efficiency filling operation so that bathtub B reaches the target filling state. This high-efficiency filling operation will be explained below according to the control flows in Figures 1, 2, and 6.

[0031] The control device 50 calculates the filling time (for example, a time of 100 to 200 minutes for a filling volume of 180 L) required to raise the volume of hot water required for filling to the target filling temperature for the target filling state based on the set volume of hot water required for filling, the water supply temperature, and the heating capacity of the heat pump water heater HP, and supplies the set volume of hot water to the bathtub at least the filling time before the set scheduled boiling time (#11). As shown in Figure 1, the control device 50 supplies water to the bathtub B by setting the second three-way valve S2 to an open state that allows hot and cold water to flow through the heating flow path R4, setting the third three-way valve S3 to a first flow state (the flow state shown in Figure 1), setting the second flow control valve V2 to an open state, and setting the fourth opening / closing valve K4 to a closed state.

[0032] Next, the controller 50 operates the first pressure pump P1 and also operates the heat pump water heater HP to perform additional heating (#12). Specifically, as shown in Figure 2, the control device 50 operates the heat pump water heater HP while stopping the combustion of the instantaneous water heater, switches the third three-way valve S3 to the second flow state (flow state shown in Figure 2: an open state in which hot water flows from the upstream side of the bath-going flow path R9a to the branch flow path R10), closes the second flow control valve V2, and opens the fourth opening / closing valve K4.

[0033] The control device 50 controls the rotation speed of the first discharge pump P1 or the opening of the first flow rate adjustment valve V1 so that the temperature of the hot water heated by the heat pump water heater HP (the temperature measured by the eighth temperature sensor T8) becomes the target reheating temperature (≧ the target filling temperature: for example, a temperature of the target filling temperature +5 to +10°C) (#13). However, the temperature measured by the eighth temperature sensor T8 is set to a temperature (for example, 48°C) or lower that will not cause burns to a user of the bathtub B. If the bath return temperature measured by the seventh temperature sensor T7 is lower than the target filling temperature (NO at #14), the control device 50 continues the control related to the above-mentioned step #13, and if the bath return temperature becomes higher than the target filling temperature (YES at #14), it stops the first pressure delivery pump P1 and the heat pump water heater HP (#15).

[0034] [Another embodiment] (1) In the above embodiment, a configuration without a hot water storage tank is shown, but instead of this configuration, a configuration with a heat source machine such as a fuel cell that heats hot water and a hot water storage tank that stores the hot water heated by the heat source machine may be adopted.

[0035] (2) In the above embodiment, a configuration example is shown in which the third three-way valve S3 as a switching valve is provided at the upstream end of the branch flow path R10, but the third three-way valve S3 may also be provided at the downstream end of the branch flow path R10.

[0036] (3) In the above embodiment, the series of configurations related to the heat pump water heater HP are shown as being provided in the bath supply flow path R9a of the reheating flow path R9, but as shown in Figure 5, a configuration in which they are provided in the bath return flow path R9b may also be adopted. In the configuration illustrated in Figure 5, in the bath return flow path R9b as the reheating flow path R9, a third three-way valve S3, a seventh temperature sensor T7, a first pressure pump P1, and a third flow rate sensor F3 are provided from the upstream side in the direction of hot water flow during reheating operation (the direction of flow shown in Figure 5), and in the bath supply flow path R9a as the reheating flow path R9, a sixth temperature sensor T6 and a fourth opening / closing valve K4 are provided in the order listed in the direction of hot water flow during reheating operation. Furthermore, the branch flow path R10 forms a flow path that branches off from the bath return flow path R9b, which serves as the reheating flow path R9, upstream of the third three-way valve S3 in the direction of hot water flow during reheating operation, and in this branch flow path R10, the eighth temperature sensor T8, condenser HEX1, and first flow control valve V1 are arranged in the order listed in the direction of hot water flow during reheating operation. In the configuration shown in Fig. 2 etc. of the above embodiment, the control device 50 measured the temperature of hot water heated by the heat pump water heater HP using the eighth temperature sensor T8, but in the configuration shown in Fig. 5, it can be measured using the seventh temperature sensor T7 (an example of a first thermometer) instead of the eighth temperature sensor T8. Also, in the configuration shown in Fig. 2 etc. of the above embodiment, the bath return temperature measured by the seventh temperature sensor T7 was used to control whether to continue or stop the high-efficiency filling operation, but in the configuration shown in Fig. 5, it may be used instead of the seventh temperature sensor T7 to control whether to continue or stop the high-efficiency filling operation.

[0037] (4) In the high-efficiency hot water filling operation according to the above embodiment, control is shown in which only a heat pump water heater HP is used as a reheating heating means. However, if it is determined that the high-efficiency hot water filling operation will not be completed by the scheduled boiling time due to external factors such as low outside air temperature, an instantaneous water heater can be used as a reheating heating means. That is, in this other embodiment (4), the control device 50 fills the bathtub B with water using the hot water supply means, and then, as a first-stage filling process, activates the first pressure pump P1 and heat pump water heater HP, which are reheating heating means, and stops the combustion of the instantaneous water heater to reheat the bathtub B, and as a second-stage filling process, activates the first pressure pump P1 and the combustion of the instantaneous water heater, which are reheating heating means, to reheat the bathtub, thereby performing a highly efficient filling operation so that the bathtub reaches the target filling state. Hereinafter, the control relating to the high-efficiency filling operation in which the latter half of the filling process may be performed in addition to the former half of the filling process will be described based on the control flows of Figs.

[0038] The control device 50 calculates the water filling time required to raise the water volume for filling to the target water filling temperature for the target filling state based on the set water volume for filling, the water supply temperature, and the heating capacity of the heat pump water heater HP, and supplies the set amount of water to the bathtub at least the water filling time before the set scheduled boiling time (#21). As shown in Figure 1, the control device 50 supplies water to the bathtub B by setting the second three-way valve S2 to an open state that allows hot and cold water to flow through the heating flow path R4, setting the third three-way valve S3 to a first flow state (the flow state shown in Figure 1), setting the second flow control valve V2 to an open state, and setting the fourth opening / closing valve K4 to a closed state.

[0039] Next, the controller 50 operates the first pressure pump P1 and also operates the heat pump water heater HP to perform additional heating (#22). Specifically, as shown in Figure 2, the control device 50 operates the heat pump water heater HP while stopping the combustion of the instantaneous water heater, switches the third three-way valve S3 to the second flow state (flow state shown in Figure 2: an open state in which hot water flows from the upstream side of the bath-going flow path R9a to the branch flow path R10), closes the second flow control valve V2, and opens the fourth opening / closing valve K4.

[0040] The control device 50 controls the rotation speed of the first pressure delivery pump P1 or the opening of the first flow control valve V1 so that the temperature of the hot water heated by the heat pump water heater HP (the temperature measured by the eighth temperature sensor T8) becomes the target reheating temperature (≧ the target filling temperature) (#23). However, the temperature measured by the eighth temperature sensor T8 is set to a temperature below which a user in the bathtub B will not get burned (for example, 48°C).

[0041] Here, if the time from the current time to the preset scheduled boiling time is less than a predetermined time (e.g., 10 minutes) set based on the execution time of the second half filling process (YES in #24), and the bath return temperature measured by the seventh temperature sensor T7 is less than the target filling temperature for the target filling state (YES in #25), the control device 50 will stop the heat pump water heater HP and activate the combustion of the instantaneous water heater to perform reheating (switch from the first half filling process to the second half filling process: #26).

[0042] Furthermore, if the time from the current time to the predetermined scheduled boiling time is greater than the predetermined time set based on the execution time of the second half filling process (NO in #24), or if the bath return temperature measured by the seventh temperature sensor T7 is higher than the target filling temperature for the target filling state (NO in #25), the switch from the first half filling process to the second half filling process is not executed (skipping #26).

[0043] If the bath return temperature measured by the seventh temperature sensor T7 is lower than the target filling temperature (NO in #27), the control device 50 continues the control related to the above-mentioned steps #23 to #26, and if the bath return temperature becomes higher than the target filling temperature (YES in #27), it stops the first pressure delivery pump P1 and, if the heat pump water heater HP is operating, stops the heat pump water heater HP, and if the combustion of the instantaneous water heater is operating, stops the combustion of the instantaneous water heater (#28).

[0044] (5) In the above-mentioned alternative embodiment (4), the heat pump water heater is stopped during the latter filling process, but the heat pump water heater may be operated.

[0045] Furthermore, the configurations disclosed in the above embodiments (including other embodiments, the same applies below) can be applied in combination with configurations disclosed in other embodiments, as long as no contradictions arise. Furthermore, the embodiments disclosed in this specification are examples, and the embodiments of the present invention are not limited to these, and can be modified as appropriate within the scope that does not deviate from the purpose of the present invention. [Industrial Applicability]

[0046] The bath device of the present invention is configured by adding a heat pump water heater to a bath device equipped with an instantaneous water heater, and can be effectively used as a bath device that can improve energy efficiency when filling the bathtub with water while also making the device more compact. [Explanation of symbols]

[0047] 11a: First burner 11b: Second burner 12: Combustion equipment 12a: 1st heat exchange section 12b:Second heat exchange section 50: Control device 100: Bath equipment B: Bathtub C2: Re-firing circuit HP: Heat pump water heater P1: First pressure pump R9: Additional firing flow path R9a: Path to the bath R9b: Bath return flow path T7: 7th temperature sensor T8: 8th temperature sensor V1: First flow control valve

Claims

1. A bath device comprising a heat pump water heater, an instantaneous water heater fueled by gas or oil, a hot water supply means for supplying hot water to a bathtub, a reheating heating means for heating the hot water in the bathtub, and an operation control means for operating at least one of the hot water supply means and the reheating heating means to perform a water filling operation to fill the bathtub with water so that the bathtub reaches a target water filling state, The instantaneous water heater has a built-in bath pump and is provided with a bath supply flow path and a bath return flow path that connect the instantaneous water heater and the bathtub, and the bath pump's water flow direction is determined by the bath pump's water flow direction. At least one of the bath supply flow path and the bath return flow path is provided with a hot water heating unit of the heat pump water heater, The operation control means operates the bath pump and the heat pump water heater, which are the reheating heating means, after filling the bathtub with water using the hot water supply means, and stops the combustion of the instantaneous water heater to reheat the bathtub, thereby performing a highly efficient water filling operation as the water filling operation so that the water filling state of the bathtub reaches the target water filling state.

2. The bath device described in claim 1, wherein the operation control means, after filling the bathtub with water using the hot water supply means, operates the bath pump and the heat pump water heater, which are the reheating heating means, as a first-stage filling process, and stops the combustion of the instantaneous water heater to reheat the bathtub, and operates the bath pump and the heat pump water heater, which are the reheating heating means, as a second-stage filling process, and reheats the bathtub, thereby performing the high-efficiency filling operation so that the bathtub's water filling state reaches the target water filling state.

3. 3. The bath device according to claim 1, further comprising a first flow rate adjusting valve that adjusts the flow rate of hot and cold water introduced to the hot and cold water heating section of the heat pump water heater.

4. A bath device as described in claim 1 or 2, wherein a first thermometer is provided between the hot water heating unit of the heat pump water heater and the bathtub to measure the temperature of the hot water being led from the hot water heating unit to the bathtub.

5. The bath device described in claim 4, wherein when the heat pump water heater is operated in the high-efficiency water filling operation, the operation control means adjusts the temperature of the hot water measured by the first thermometer to a target reheating temperature, which is a temperature higher than the target water filling temperature for the target water filling state, using at least one of the bath pump built into the instantaneous water heater and a first flow control valve capable of adjusting the flow rate of the hot water led to the hot water heating section of the heat pump water heater.

6. A bath return thermometer is provided to measure the temperature of the hot water flowing from the bathtub to the bath return flow path, The bath device described in claim 2, wherein the operating control means switches from the first-stage filling process to the second-stage filling process when the time from the current time to the predetermined scheduled heating time is less than a predetermined time set based on the execution time of the second-stage filling process, and the bath return temperature measured by the bath return thermometer is less than the target filling temperature for the target filling state.

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