JPH10253152A - Bathtub device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To purify the fur or various germ which accumulate at a circulating channel of bathtub water. SOLUTION: In purifying a circulating channel of bathtub water, the fur or each kind of germ, which accumulate at the circulating channel, are washed, sterilized, and purified by supplying the water containing chlorine residue to the circulating channel of the bathtub water, a circulating adaptor 3 without the primary filter, a return pipe 5, a circulating pump 6, a tank filter 7, and a flow pipe 9. In this way, the circulating channel can be always kept clean, even if two or more people take a bath or use bathtub water continuously.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bathtub device capable of purifying and sterilizing a water circuit for circulating bathtub water in a bathtub to keep the bathtub clean.

[0002]

2. Description of the Related Art Conventionally, there is a bathtub apparatus for purifying a water circuit of bathtub water in a bathtub as shown in FIG.

The bathtub water 1 is filled with a return pipe 5, a circulation pump 6, and a filter material 8 connected to a return portion of a circulation adapter 3 provided with a wire mesh filter 4 for purifying large scales, hair and the like attached to the bathtub 2. The circulating pump 6 circulates a water circuit composed of an outgoing pipe 9 connected to the outgoing part of the circulating adapter 3 through the filtered tub 7, and removes the dirt component of the bathtub water 1 by the filtering tub 7.
Had been purified.

In the water circuit of the bathtub water 1, a heating means A10, which is a heating tank for heating the bathtub water 1, is provided between the circulation pump 6 and the filtration tank 7.

Further, the hot water to the bathtub 2 is connected to a part of the circulation water circuit via a heating means B11 which is a heating source of the water circuit, and is supplied through a return pipe 5 and a forward pipe 9.

[0006]

However, in a conventional bathtub apparatus for purifying a water circuit of bathtub water, first, large dirt, hair, etc., which are dirt components of bathtub water, are simply purified by a primary filter installed in a circulation adapter. However, if the primary filter is clogged with large scale and hair, the circulation flow rate of the bathtub by the circulation pump is significantly reduced,
The circulating purification efficiency of bathtub water in the bathtub deteriorates. The user must periodically clean the clogged primary filter, but since the primary filter is in bathtub water, it is difficult to visually check the primary filter, and the primary filter is hardly cleaned at present. In addition, when hot water is applied, large dirt and hair clogged in the primary filter are re-flowed into the bath tub at once, thereby increasing bath water dirt. The relatively large dirt particles (approximately 10 microns or more) that have passed through the primary filter can be filtered and purified by the filtration tank in the water circuit. The water component is liable to become dirty and unclean due to insufficient filtration and purification of the fine particles (approximately 1 micron) caused by various bacteria (general bacteria, E. coli, etc.) in the filtration tank. More importantly, the connection between the circulation pump, filtration tank, feed pipe, return pipe and the adapter for circulation is an uneven structure, and the water flow is poor (large turbulence), and nutrient sources of various bacteria are important. It is an environment where dirt is easily deposited and various bacteria are easily proliferated. Especially up to the inlet of the filtration tank,
Since the dirt components of the bathtub water circulate as they are, they tend to become more unclean.To keep them clean and clean, always replace the bathtub water and clean the primary filter of the circulation adapter from time to time. Forcibly cleaning must be performed, either by cleaning or further by passing water through a cleaning agent, so that there is a problem that the operation is very uneconomical and time-consuming.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a method for purifying a bath circuit for circulating bath water, comprising: a circulating adapter, a return pipe, a circulating pump, and a filtration tank without a primary filter. In addition, the residual chlorine-containing water is passed through a water supply section connected to a part of the water circuit, and the residual chlorine-containing water is retained as necessary.

[0008] According to the above invention, large dirt particles, hair, and the like, which are dirt components of bathtub water, are operated through a circulation pump, passed through a circulation adapter, return pipe, and circulation pump without a primary filter, and filled in a filtration tank. By filtering and purifying with a filtered filter material, it does not flow out again into the bathtub water of the bathtub, and the dirt component of the bathtub water can be suppressed to the minimum. In addition, by passing small bacteria containing water that is difficult to filter and purify in the filter tank, the water containing residual chlorine can be sterilized and purified, and the circulation water circuit can always be kept clean. Also, by keeping the water circuit clean and clean at all times, a plurality of people can take a continuous bath or use the bathtub water continuously.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A circulating pump provided in a part of a water circuit for circulating bath water, a filtration tank for filtering bath water, a circulating adapter for connecting the bath tub and the water circuit, and supplying water to the water circuit. A water supply section is provided, bathtub water is purified only by the filtration tank, and the water supply section is for passing residual chlorine-containing water through the water circuit to clean the water circuit.

[0010] The residual chlorine-containing water is passed through a water circuit without a primary filter for purifying large scales and hair on the return side of the circulation adapter, and large scale particles and hair, which are dirt components of the bathtub water. Adapter for circulation, return pipe,
By passing through a circulation pump, filtering and purifying with a filter medium filled in a filtration tank, and supplying residual chlorine-containing water for a certain period of time, the accumulation of dirt on the uneven components of the circulation water circuit is washed or reduced by the hydraulic power. Even so, it hardly re-flows into the bath water of the bathtub, and the dirt of the bathtub water can be minimized. In addition to suppressing the growth of various bacteria, and by sterilizing and purifying various bacteria that are difficult to filter and purify in the filtration tank with residual chlorine-containing water, the water circuit is always kept clean and clean, so that multiple people can take a continuous bath. You can continue to use or bath water.

Further, a switching valve for switching the water supply direction of the water circuit is provided, and when the residual chlorine-containing water is supplied from the water supply section to the water circuit, the switching valve is switched to the return side or the forward side.

Since the residual chlorine-containing water is supplied only to the return side or the outgoing side, the amount of water supplied to the return side and the outgoing side improves the chlorine cleaning ability as compared with the case where water is supplied simultaneously to the return side and the outgoing side. be able to.

Further, after the residual chlorine-containing water supplied from the water supply section reaches the circulation adapter via the water circuit, the supply of water is abolished, and the residual chlorine-containing water stays in the water circuit for a certain period of time.

After the residual chlorine-containing water is passed through at least the entire volume of the bathtub water circuit, the residual chlorine-containing water is retained in the water circuit for a certain period of time to purify the water with a greater temporal sterilization effect. be able to.

Further, a heating means for heating the residual chlorine-containing water is provided. Further, after the hot water heated by the residual chlorine-containing water heating means is supplied to the water circuit, the residual chlorine-containing water not heated by the heating means is supplied to the water circuit.

Then, as the flow temperature of the residual chlorine-containing water,
By passing cold water after hot water, the cold water flow delays the decomposition of residual chlorine and maintains the residual chlorine concentration to increase the sterilization effect, and the hot water flow accumulates on the uneven parts of the water circuit. It is possible to reduce the adhesion of the scale, wash or reduce the scale accumulation, and increase the purification ability.

Further, the temperature of the residual chlorine-containing water heated by the heating means is set to 55 ° C. or higher.

[0018] By setting the temperature of the residual chlorine-containing water passing through to 55 ° C or higher, even if the residual chlorine concentration is reduced, various bacteria by high-temperature water are sterilized at a high temperature. Due to the synergistic effect, the sterilization time can be reduced.

Further, tap water is used as the residual chlorine-containing water supplied from the water supply section.

Then, as residual chlorine containing water that passes through,
By using tap water, it is possible to use water supplied to ordinary households, so that purification with excellent convenience and economy can be performed.

(Embodiment 1) A bathtub apparatus for purifying a bathtub water circuit in Embodiment 1 of the present invention will be described below with reference to the drawings. Note that the same components as those in the related art are denoted by the same reference numerals and described.

In FIG. 1, dirt components such as large dirt particles and hair in the bathtub water 1 can be circulated by operating a circulation pump 6 according to a signal from a control unit without a primary file attached to the bathtub 2 as a water circuit. A return pipe 5, a circulation pump 6, a switching valve A12, and a switching valve C14 of a switching valve B13, which are connected to a return portion of the circulation adapter 3 through the adapter 3, pass through the filter medium 8 filled in the filtration tank 7 in a downward flow. Filtration and purification of dirt components such as large scale particles and hair. Then, the purified bathtub water 1 passes through the switching valve D15, returns to the bathtub 2 from the going pipe 9 connected to the going portion of the circulating adapter 3 attached to the bathtub 2, and returns to the bathtub 2 via the circulating adapter 3, and is circulated by the signal of the control unit. The bath water 1 circulates until the pump 6 stops.

When the filter material 8 filled in the filter tank 7 is clogged with dirt components (large dirt particles, hair, etc.) of the bath water 1, the circulation pump 6 is temporarily stopped by a signal from the control unit, and the switching valve B13 is stopped. , A passage on either the side of the heating source 10 for heating the bathtub water 1 or the side of the bypass passage 17 is formed, and the switching valve C14 and the switching valve D15 are switched to the backwash drainage side. The circulation pump 6 is operated again to use the bathtub water 1, the switching valve B <b> 13, the heating source 10 for heating the bathtub water 1, or the bypass passage 17.
The dirt component filtered through the filter medium 8 filled in the filter tank 7 in an upward flow through the bypass passage 17, the lower backwash passage 18, and the switching valve D15 from one of the passages on the side is backwashed and washed. The washed and washed bath water 1 is drained from a drain pipe 17 connected to a switching valve C14. Further, when the bathtub water 1 in the bathtub 2 is drained for a certain period of time, the circulation pump 6 is stopped by a signal from the control unit, and the switching valve A is switched to allow a certain amount of residual chlorine-containing water to flow, thereby returning the return pipe. 5, the circulation pump 6, the switching valve B13, the switching valve C14 and the switching valve D of the upper going pipe 16 from the bypass passage 17 side or the heating source 10 side.
Cleaning and reducing and purifying the water circuit consisting of 15 and the accumulation of debris that accumulates on the unevenness of the water circuit, in particular, as a nutrient source of various bacteria, and purifies and sterilizes and purifies various bacteria with residual chlorine. Can be. 2 (a) is a cross-sectional fitting configuration diagram, and FIG. 2 (b) is a front configuration diagram of the above (a), showing a configuration diagram of the circulation adapter 3 attached to the bathtub. Return pipe 5,
A connecting body 31 for connecting the going pipe 9 and a connecting body 31
Are fixedly connected to the bathtub 2, a water seal packing A33 and a packing B34 are respectively provided between the connection body 31 and the bathtub 2, and between the bathtub 2 and the fixing screw 32.
Then, a connecting portion 38 provided in a case 37 in which a forward (discharge) passage 35 and a return (suction) passage 36 of the fixing screw 32 are separated from each other, is inserted into a fitting portion 40 of the connection die 31 with an O-ring 39. The projection 42 provided on the case 37 is fitted into the groove 41 of the fixing screw 32 by using a spring force.

Next, a method of passing water from a water supply unit provided in a part of the water circuit will be described in detail. As the water flow to the bathtub water circuit, (1) the outgoing water circuit water flow, (2) the return water circuit water flow,
(3) Deposition of dirt, which is a source of various bacterial nutrients in the whole water circuit, by repeatedly passing water through the outgoing and return water circuits or (4) returning water containing residual chlorine as simultaneous water flow through the outgoing water circuit. , And various bacteria can be sterilized and purified by residual chlorine.

Next, the residual chlorine-containing water will be described in detail.
The residual chlorine-containing water is fresh water containing 0.1 ppm or more of residual chlorine, in which chlorine gas is dissolved, and in which sodium hypochlorite is dissolved, and whose concentration is controlled. As the concentration control, the residual chlorine concentration was 0.1%.
ppm or more, but as a material of the components of the water circuit,
Copper and copper alloys, NBR and EPDM rubbers, PP and POM resins, and the like are generally used, and considering the durability of these materials, the content is preferably 10 ppm or less. In addition, when the sterilization and purification are made effective in a short period of time and the durability of the component parts is taken into consideration, the preferable residual chlorine concentration of the residual chlorine-containing water is 0.3 to 5 ppm.

FIG. 3 shows a configuration of a water circuit for determining the purification effect of the present invention and the conventional method and a configuration of a purification determination plate.
(A) is a configuration diagram of a water circuit, in which a purification determination plate unit 20,
Reference numeral 21 denotes a return pipe 5 connected to the circulation adapter 3 and a forward pipe 9.
Are installed. (B) is a top view configuration diagram of the purification determination plate portions 20 and 21, and (c) is a cross-sectional configuration diagram of the purification determination plate portions 20 and 21, and shows the purification determination plate 22.
(A white resin plate having a width of 10 mm and a thickness of 1 mm) is attached to the water passing portions of the return pipe 5 and the forward pipe 9 via a sealing jig.

Table 1 shows the purification effects of the present invention and the conventional method using the water circuit configuration detailed in FIG. As detailed conditions and evaluations not described in the table, bathing conditions: 4 persons / day, 42 ° C./4 hours heat retention, purification conditions:
The residual chlorine concentration of residual chlorine-containing water when passing water is 0.5 to 1
ppm, bath water temperature: 42 ° C./4 hours, except natural heat, natural cooling, circulation conditions: after continuous operation of the circulation pump for 11 hours, 1 minute at a backwash flow rate of the filter tank of 2 l / minute, stop of the circulation pump for 59 minutes and evaluation: Evaluation index in Table 2 (dirt index 5)
Grade evaluation: Color change = dirt accumulation was visually evaluated).

[0028]

[Table 1]

[0029]

[Table 2]

As is clear from Table 1, by passing residual chlorine-containing water, dirt components (dirt) that easily accumulate in the circulation water circuit can be reduced. In addition, generally-known scale (thing in which scale is a nutrient source and abnormal growth of various bacteria) is likely to occur at an evaluation index of 4 level,
According to the return index rating index 4 of the conventional method, the scale was generated although it was very small. By passing the residual chlorine-containing water of the present invention, the growth of various bacteria was suppressed, and the water circuit was cleaned. Can be kept. In addition, in the case of the circulation adapter provided with the conventional primary filter, the circulation flow rate was 8.5 l / min on the 7th day, 6 l / min on the 15th day, and 2.
The circulation flow rate was greatly reduced to 5 l / min. On the other hand, the circulation flow rate of (2) and (4) of the present invention was 9.5 l / min on the 30th day, and the circulation flow rate hardly decreased.

(Embodiment 2) A bathtub apparatus for purifying a bathtub water circuit according to Embodiment 2 of the present invention will be described with reference to FIGS.

In FIG. 4, the circulating pump 6 is stopped by a signal from the control unit, and the switching valve A12 is switched so that the residual chlorine-containing water is supplied to the water circuit in the water pipe 9 and return pipe 5 described in the first embodiment. Through the water circuit at the same time. And
After passing water at least for the entire water circuit capacity, the switching valve A12
Is switched to stop the passage of the residual chlorine-containing water and stay for a certain period of time, that is, the stay set time, to further enhance the sterilizing and purifying effect. The flow of water of at least the total water circuit capacity in the second embodiment means the distance from the circulation adapter 3 fixedly connected to the bathtub 2 as a water circuit to a circulation device including the circulation pump 6, the filtration tank 7, and the like, that is, the circulation device. Although it depends on the construction conditions of the circulating device, it means the total water circuit capacity in consideration of the maximum distance which is the construction condition of the circulation device.

Next, the fixed time, that is, the stay setting time is:
It is determined by the residual chlorine concentration of the residual chlorine-containing water. Although the bactericidal concentration and time are different depending on various bacteria, in general, when the residual chlorine concentration is low, the setting time is long, and when the residual chlorine concentration is high, the setting time is short, FIG. 5 shows the sterilization evaluation performed by the present inventors. The sterilization evaluation conditions were as follows: water sample volume: 500 ml, water temperature: 20 ° C.
The test was carried out under various conditions of initial general bacteria count: 5,000,000 cells / ml and residual chlorine concentration: 0, 0.1, 0.5, 2 ppm.

As shown in FIG. 5, the residence time for reducing the number of general bacteria to 100 cells / ml or less based on tap water is as follows:
Low residual chlorine concentration of water containing residual chlorine is about 1 at 0.1 ppm
5 minutes, 0.5 ppm at about 5 minutes, and 2 ppm at about 2 minutes. Therefore, the preferred residence time depends on the residual chlorine concentration, but is at least 15 minutes.

(Embodiment 3) A bathtub apparatus for purifying a bathtub water circuit according to Embodiment 3 of the present invention will be described with reference to FIG.

In FIG. 6, the switching valve A12 is switched by a signal from the control unit, and at the same time, the heating source 1 of the hot water supply water circuit is switched.
In step 1, the residual chlorine-containing water is simultaneously heated and passed through the return and outgoing water circuit of (4) described in detail in Example 1 by the total water circuit capacity. Next, after the set water flow rate is passed, the water is allowed to stay for the set time according to the signal of the control unit. In particular, the adhesion force of the deposits deposited on the unevenness of the water circuit is reduced to increase the separation and purification effect. Then, the heating source 11 of the hot water supply water circuit is stopped,
After passing through cold water containing residual chlorine (at atmospheric temperature level that is not mechanically cooled) again, if necessary, stay for the set time for stay again according to the control signal to further increase the sterilization and purification effect. Can be. In addition, when the temperature of the heating water is high, the temperature of the water circuit also rises at the same time. Therefore, after staying for a certain period of time, the components of the water circuit are cooled in consideration of durability, prevention of burns, and the like.

(Embodiment 4) A bathtub apparatus for purifying a bathtub water circuit according to Embodiment 4 of the present invention will be described with reference to FIGS.

In FIG. 7, the switching valve A12 is switched by a signal from the control unit, and at the same time, the heating source 1 of the hot water supply circuit is switched.
In step 1, the residual chlorine-containing water is passed through the return and outgoing water circuit of (4) described in Example 1 at the same time as the total water circuit capacity. Next, after the set water flow rate is passed, the bacteria are retained for the retention time by the signal of the control unit, so that various bacteria can be more reliably sterilized and purified by the synergistic effect of high-temperature sterilization and residual chlorine-containing water.

Next, high-temperature sterilization is to sterilize by utilizing the property that various sterilizations are weak to high temperatures. Although the high-temperature sterilization temperature and time are different depending on various sterilizations, generally, when the temperature is relatively low, the holding time is long, and when the temperature is high, the holding time is short. FIG. 8 shows the results of the high-temperature sterilization evaluation performed by them. The high-temperature sterilization evaluation conditions in FIG. 8 are as follows: water sample amount: 100 ml, initial general sterilization number:
5,000,000 / ml was placed in a beaker, and a thermocouple was immersed in the above test water, which was heated in a microwave oven, and tested under the conditions of water temperature: 50, 55, 60, 65, 70 ° C. The above-mentioned heating temperature is the maximum temperature of the temperature rise, the tolerance 2
deg, and the holding time was maintained in a constant temperature water bath. The holding time is the maximum temperature at which the temperature rises, with a tolerance of 2 de.
g.

As shown in FIG. 7, the heating temperature for reducing the number of general bacteria to 100 cells / ml or less based on tap water is as follows.
5 minutes or more at 55 ° C. or more is required. At 60 ° C,
When the temperature reaches 60 ° C., almost 100% high-temperature sterilization and purification can be performed.

(Embodiment 5) A bathtub apparatus for purifying a bathtub water circuit according to Embodiment 5 of the present invention will be described with reference to FIG.

In FIG. 8, the switching valve A6 is switched by the signal of the control unit, and at the same time, the tap water used in ordinary households as the residual chlorine-containing water is described in detail in the third embodiment by the set flow rate. By simultaneously passing water through the return and outgoing water circuits in 2), a purification method excellent in convenience and economy can be provided.

[0043]

As described above, the bathtub apparatus for purifying the water circuit of the bathtub water according to the present invention comprises a circulating adapter, a return pipe, a circulating pump, a filtration tank, a going pipe and a circulating adapter without a primary filter. Using a water circuit, while filtering and purifying dirt components of bathtub circulating water by the circulation pump,
By passing residual chlorine-containing water for a certain period of time, there is no reduction in the circulating flow rate due to clogging of the primary filter. By washing or reducing dirt accumulation, which is a nutrient source of various bacteria that are easy to accumulate, with hydraulic power, sterilizing and purifying various bacteria by suppressing growth from residual chlorine,
Keeping the water circuit clean and clean at all times allows more than one person to use or bath water continuously. In addition, by allowing the residual chlorine-containing water to stay at least for a certain period of time after passing the residual chlorine-containing water through at least the entire volume of the bathtub water circuit, the circulating water circuit can be further purified by increasing the sterilizing and purifying effect. In addition, by repeatedly passing cold water and hot water, it is possible to further reduce the accumulation of dirt, which is a nutrient source of various bacteria, which easily accumulates on the concavo-convex portion of the connection part of the water circuit, and suppress the growth of various bacteria. Further, by passing the water at a high temperature under heating, the sterilization can be performed more reliably by the synergistic effect of the high temperature sterilization and the residual chlorine-containing water. Furthermore, by passing tap water as residual chlorine-containing water, purification can be performed with excellent convenience and economy.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a circulation water circuit according to a first embodiment of the present invention.

FIG. 2A is a cross-sectional configuration diagram of a circulation adapter used in the first embodiment of the present invention. FIG. 2B is a front configuration diagram of a circulation adapter used in the first embodiment of the present invention.

FIG. 3A is a configuration diagram of a circulating water circuit for a comparative test of Example 1 of the present invention and a conventional method. FIG. 3B is a top view of a purification plate portion of the circulating water circuit for the comparative test. Configuration diagram of the purification plate part of the water circulation water circuit

4A is a configuration diagram of a circulation water circuit according to a second embodiment of the present invention. FIG. 4B is a flowchart illustrating a purification mode of the circulation water circuit.

5A is a diagram showing the sterilization evaluation effect of Example 2 of the present invention. FIG. 5B is a diagram showing the same sterilization evaluation effect.

FIG. 6A is a configuration diagram of a circulation water circuit according to a third embodiment of the present invention. FIG. 6B is a flowchart illustrating a purification mode of the circulation water circuit.

7A is a configuration diagram of a circulation water circuit according to a fourth embodiment of the present invention. FIG. 7B is a flowchart illustrating a purification mode of the circulation water circuit.

FIG. 8 (a) is a diagram showing the high-temperature sterilization evaluation effect of Example 4 of the present invention.

FIG. 9 is a configuration diagram of a circulation water circuit according to a fifth embodiment of the present invention.

FIG. 10 is a configuration diagram of a conventional bath water circulation water circuit.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Bath water 3 Circulation adapter 5 Return pipe 6 Circulation pump 7 Filtration tank 8 Filtration material 9 Outgoing pipe 10 Heat source (heating means A) 11 Heat source (heating means B) 12 Switching valve A 13 Switching valve B 14 Switching valve C Reference Signs List 15 switching valve D 16 upper going passage 17 bypass passage 18 lower backwash passage 20, 21 purification judgment plate portion 22 purification judgment plate 31 connection body 32 fixing screw 35 going (discharge) passage 36 return (suction) passage 37 case

Continuation of the front page (51) Int.Cl. ⁶ Identification code FI C02F 1/50 531 C02F 1/50 540B 540 550H 550 560Z 560 F24H 9/00 W F24H 9/00 B01D 35/02 J (72) Inventor Aoki Tetsuro 1006 Kazuma Kadoma, Kadoma City, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. (72) Hiroaki Yamauchi 1006 Kadoma Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (6)

[Claims] 1. A circulating pump provided in a part of a water circuit for circulating bath water, a filtration tank for filtering bath water, a circulation adapter for connecting the bath tub and the water circuit, and a water supply for supplying water to the water circuit. A bathtub device for purifying bathtub water only by the filtration tank, and supplying a residual chlorine-containing water to the water circuit to clean the water circuit. 2. A switching valve for switching a water supply direction of a water circuit, wherein when the residual chlorine-containing water is supplied from the water supply section to the water circuit, the switching valve is switched to a return side or a forward side.
Bathtub device as described. 3. After the residual chlorine-containing water supplied from the water supply section reaches the circulation adapter via the water circuit, the supply of water is abolished, and the residual chlorine-containing water remains in the water circuit for a certain period of time. The bathtub apparatus according to 2. 4. The bathtub apparatus according to claim 1, further comprising heating means for heating the residual chlorine-containing water. 5. The bathtub apparatus according to claim 4, wherein after the residual chlorine-containing water heated by the heating means is supplied to the water circuit, the residual chlorine-containing water not heated by the heating means is supplied to the water circuit. 6. The bathtub apparatus according to claim 1, wherein the temperature of the residual chlorine-containing water heated by the heating means is set to 55 ° C. or higher.