Air conditioning system

Abstract

The present invention provides an air conditioning system that can improve the heat exchange efficiency of the immersion-type heat exchanger 6 and reduce temperature unevenness in the stored water sw of the tank 5. [Solution] The immersion-type heat exchanger 6 is serpentine in the vertical direction and is positioned along the inner surface 51a of the right wall, the inner surface 52a of the left wall, and the inner surface 53a of the rear wall of the tank 5. Therefore, the heat exchange area can be made larger than that of a heat exchanger that extends in only one direction, thereby increasing the heat exchange efficiency. In addition, the temperature unevenness of the water can be reduced compared to a heat exchanger that extends in only one direction.

Description

Technical Field

[0001] The present invention relates to an air conditioner equipped with an immersion type heat exchanger.

Background Art

[0002] Conventionally, as this type of air conditioner, an air conditioner described in Patent Document 1 is known. This air conditioning system includes an outdoor unit 5 and an indoor unit 6. The outdoor unit 5 includes a compressor 1, a first heat exchanger 2, a first fan 3, and a flow control valve 4. The indoor unit 6 includes a heat storage tank 12 in which water 11 is stored, a third heat exchanger 10 immersed in the water 11, a pump 13, a fourth heat exchanger 14, and a second fan 9. The compressor 1 of the outdoor unit 5 and the third heat exchanger 10 are connected by a refrigerant pipe 7a, and the flow control valve 4 and the third heat exchanger 10 are connected by a refrigerant pipe 7b. The third heat exchanger 10 is a plate type heat exchanger 10C (Figure 4 of the patent document), or a plate fin tube type heat exchanger 10A (Figure 2 of the patent document), or a structure in which a large number of fins are wound around a pipe (Figure 3 of the patent document).

[0003] When the compressor 1 of the outdoor unit 5 is driven by a motor or the like, the refrigerant gas is compressed and becomes a high-temperature and high-pressure state. This high-temperature and high-pressure refrigerant gas is cooled and condensed and liquefied inside the first heat exchanger 2. The heat generated at this time is removed by the outdoor air sent by the first fan 3. The liquefied liquid refrigerant is depressurized by the flow control valve 4 and sent to the third heat exchanger 10 of the indoor unit 6 through the refrigerant pipe 7b. Then, in the third heat exchanger 10, the liquid refrigerant evaporates and the water 11 is cooled. This cooling water is sent to the fourth heat exchanger 14 by the pump 13. When the fourth heat exchanger 14 becomes low in temperature and the second fan 9 sends indoor air to the fourth heat exchanger 14, the indoor air is cooled and becomes cold air, and the room is cooled.

Prior Art Documents

Patent Documents

[0004] [Patent Document 1] Japanese Patent Application Publication No. 10-176849 [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] However, the air conditioning system disclosed in Patent Document 1 has the problem that the third heat exchanger 10 located in the heat storage tank 12 extends in only one direction, resulting in low heat exchange efficiency and large temperature variations in the water 11.

[0006] Therefore, the present invention was created to solve the above-mentioned problems, and aims to provide an air conditioning system that can improve the heat exchange efficiency of an immersion-type heat exchanger and reduce temperature variations in the water stored in the tank. [Means for solving the problem]

[0007] (First design) In order to achieve the aforementioned objective, the first invention of this application, A water storage tank (5), A heat exchanger (6) is immersed in water (sw: Figure 4) stored in a tank (5), A condensing unit (30: Figure 3) supplies a heat transfer medium to the heat exchanger (6), An air conditioning system (1) comprising a fan coil unit (20: Figure 3) to which water (sw) stored in a tank (5) is supplied, The tank (5) has at least four inner surfaces (51a, 52a, 53a, 54a: Figure 5) along its inner circumference, The heat exchanger (6) is It is characterized in that it is arranged along at least two of the four inner surfaces (51a, 52a, 53a, 54a).

[0008] (Effects of the first invention) According to the first invention, since the heat exchanger is positioned along at least two of the at least four inner surfaces of the tank, the heat exchange area can be made larger than in a heat exchanger that extends in only one direction, and thus the heat exchange efficiency can be increased. Furthermore, it can reduce temperature variations in the water compared to heat exchangers that extend in only one direction.

[0009] (Second design) In the second invention of the present application, in the air conditioning device (1) of the first invention, Tank (5) is The horizontal cross-sectional shape is rectangular, and it has four inner surfaces consisting of the front inner surface (54a), the rear inner surface (53a), the right inner surface (51a), and the left inner surface (52a). The heat exchanger (6) is It is characterized in that it is positioned along the inner surface of the rear wall (53a), the inner surface of the right side wall (51a), and the inner surface of the left side wall (52a), but is not positioned along the inner surface of the front wall (54a).

[0010] (Effects of the second invention) According to the second design, the heat exchangers are arranged along the inner surfaces of the rear, right, and left walls of the inner circumference of the tank, but not along the inner surface of the front wall. Therefore, the heat exchangers on each inner surface can be clearly seen from the front, making it easier to perform maintenance or repairs on the heat exchangers. Furthermore, if the heat exchanger is positioned along the inner surface of the front wall, the flow inside the tank becomes enclosed, potentially obstructing the convection path. However, by not positioning the heat exchanger along the inner surface of the front wall, convection inside the tank becomes more active, thereby improving the heat exchange efficiency.

[0011] (Third idea) In the third invention of this application, in the air conditioning device (1) of the first or second invention, The heat exchanger (6) is It has heat transfer tubes (6a, 6b: Figure 4) through which the heat transfer medium flows, The heat medium pipes (6a, 6b) are characterized by meandering in the vertical direction.

[0012] (Effect of the third invention) According to the third invention, since the heat medium pipes meander in the vertical direction, when the low-temperature heat medium flows through the heat medium pipes during cooling, the water around the heat medium pipes is cooled, its specific gravity increases, and a downward flow occurs. This downward flow induces natural convection, and circulation occurs throughout the tank, so the temperature unevenness in the height direction can be reduced. Also, when the high-temperature heat medium flows through the heat medium pipes during heating, the water around the heat medium pipes is heated, its specific gravity decreases, and an upward flow (chimney flow) occurs. This upward flow induces natural convection, and circulation occurs throughout the tank, so the temperature unevenness in the height direction can be reduced.

[0013] (Fourth invention) In the fourth invention of the present application, in the air conditioner (1) of the first or second invention, a gap (s: Fig. 5) is formed between the inner surfaces (51a, 52a, 53a) arranged along the heat medium pipes (6a, 6b) and the heat medium pipes.

[0014] (Effect of the fourth invention) According to the fourth invention, since a gap is formed between the inner surfaces arranged along the heat medium pipes and the heat medium pipes, the water in the tank can flow around the outer periphery of the heat medium pipes in all directions, so natural convection is likely to occur. Therefore, circulation is likely to occur throughout the tank, so the temperature unevenness in the height direction can be further reduced. Also, since the entire circumference of the heat medium pipes is in contact with water, the heat transfer area can be effectively utilized, so the heat exchange efficiency can be increased.

[0015] (Fifth invention) In the fifth invention of the present application, in the air conditioner (1) of the first or second invention, There is provided a water spraying device (13: Fig. 4) that sprays water (rw: Fig. 4) returned from the fan coil unit (20) onto the water (sw) stored in the tank (5).

[0016] (Effect of the fifth invention) According to the fifth invention, since the water returned from the fan coil unit can be sprayed onto the water stored in the tank, the returned water can be distributed and supplied over the wide surface of the water in the tank. Therefore, since the water returned from the fan coil unit can be rapidly mixed with the water in the tank, the heat of the water returned from the fan coil unit diffuses uniformly, and thus the temperature unevenness can be further reduced.

[0017] (Sixth invention) In the sixth invention of the present application, in the air conditioner (1) of the first or second invention, it includes a housing (3: Fig. 1) having a fan coil unit (20) provided therein, at a predetermined location on the peripheral surface of the housing (3), there is provided an air outlet (4d: Figs. 2(A), 3) for the fan coil unit (20) to blow air into the room, and it is characterized in that intake ports (4a, 4b, 4c) for the fan coil unit (20) to intake air are provided on at least two surfaces (3a, 3b, 3c: Fig. 2) of the peripheral surface of the housing (3).

[0018] (Effect of the sixth invention) According to the sixth invention, since intake ports for the fan coil unit to intake air are provided on at least two surfaces of the peripheral surface of the housing having the fan coil unit provided therein, the intake efficiency can be enhanced, and thus the air conditioning efficiency can be enhanced.

[0019] (Seventh invention) In the seventh invention of the present application, in the first or second air conditioner (1), a tank (5) is arranged below the fan coil unit (20), The fan coil unit (20) and tank (5) are located inside the room. The condensing unit (30) is characterized by being located outdoors.

[0020] (Effects of the seventh invention) When the tank is placed outdoors, the tank's exterior walls and water supply pipes absorb heat from the outside air, causing the water temperature to rise easily. This leads to an increase in the water temperature at the heat exchanger inlet of the fan coil unit, reducing the temperature difference between the heat exchanger inlet and outlet, resulting in a decrease in cooling capacity. However, according to the seventh invention, since the tank is located indoors, the influence of outside air on the water temperature is reduced, and the temperature difference between the inlet and outlet of the heat exchanger of the fan coil unit can be increased, thereby improving the cooling capacity.

[0021] Furthermore, if the condensing unit and tank are located outdoors, it is necessary to connect the heat exchanger of the indoor fan coil unit to the tank with intake and drainage pipes. However, these intake and drainage pipes have a large radius and are heavy. They also have large bending radii and an increased number of joints. In short, installation is difficult and the flexibility of the piping is limited. Moreover, modifying existing systems is difficult. However, according to the seventh invention, since the condensing unit located outdoors and the heat exchanger of the tank located indoors are connected by a heat transfer pipe, the pipe radius is smaller and lighter compared to the intake and drainage pipe. In addition, the bending radius is smaller and the number of joints is reduced. In other words, it is easier to install and offers greater flexibility in piping. Furthermore, it makes it easier to renovate existing systems. Furthermore, because the tank is located below the fan coil unit, the horizontal width of the unit placed inside the room can be reduced, thus increasing the flexibility of the installation location inside the room.

[0022] The reference numerals and figure numbers within the parentheses above indicate the correspondence with the specific means described in the embodiments described later. [Effects of the Invention]

[0023] According to the present invention, it is possible to provide an air conditioning system that can improve the heat exchange efficiency of an immersion-type heat exchanger and reduce temperature variations in the water stored in the tank. [Brief explanation of the drawing]

[0024] [Figure 1] This is an explanatory diagram conceptually showing the main components of an air conditioning system according to an embodiment of the present invention. [Figure 2] Figure 1 is a perspective view illustrating the indoor unit of the air conditioning system shown. [Figure 3] (A) is a front view of the indoor unit shown in Figure 2, (B) is a left side view, and (C) is a right side view. [Figure 4] Figure 2 is a conceptual perspective view illustrating the tank and heat exchanger of the indoor unit. [Figure 5] (A) is an explanatory diagram of the tank and heat exchanger shown in Figure 4, viewed from above, and (B) is an explanatory diagram viewed from the front. [Figure 6] This is a conceptual perspective view illustrating a tank and heat exchanger of an air conditioning system according to another embodiment of the present invention. [Modes for carrying out the invention]

[0025] An air conditioning system according to an embodiment of the present invention will be described with reference to Figures 1 to 5. [Main configuration] First, the main components of the air conditioning system will be explained with reference to Figure 1. The air conditioning system 1 of this embodiment is of the heat pump type and comprises an indoor unit 1A mainly located indoors and an outdoor unit 1B mainly located outdoors. In this specification, "indoors" refers to a space partitioned from the outside air by a roof and walls, etc., and includes, but is not limited to, living rooms in ordinary homes, greenhouses, rooms in buildings, gymnasiums, theaters, cinemas, halls, commercial facilities, factories, etc. Furthermore, "outdoors" is not limited to the open air, but refers to a space partitioned from the space where the indoor unit is located, which is in communication with the outside air or has an environment where direct exhaust to the outside is possible, and includes, but is not limited to, balconies, machine rooms, ducts, equipment spaces, compartments with openings to the outside air in attics or pits, corridors equipped with ventilation equipment that exhausts to the outside, etc.

[0026] The indoor unit 1A is equipped with a base 2 (Figure 2) for installation on the floor, and a housing 3 with a rectangular horizontal cross-section is mounted on the base 2. Inside the housing 3, a tank 5 is located at the bottom, and a fan coil unit 20 is located above the tank 5. The internal space of the housing 3 is divided into the space where the tank 5 is located and the space where the fan coil unit is located (air chamber). The fan coil unit 20 is equipped with a heat exchanger 21 and a fan 22. The fan coil unit 20 is equipped with a temperature sensor 23 that outputs a signal corresponding to the internal temperature of the fan coil unit 20, that is, the room temperature. Based on the detection signal from the temperature sensor 23, the rotation speed of the fan 22 is controlled, and the airflow is controlled. Water is stored inside tank 5. Hereinafter, the water stored in tank 5 will be referred to as stored water sw. An immersion-type heat exchanger 6 is immersed in the stored water sw. In addition, a temperature sensor 10 that outputs a signal corresponding to the temperature of the stored water sw is located in tank 5.

[0027] The outdoor unit 1B is equipped with a condensing unit 30. The condensing unit 30 includes a compressor 31, a four-way valve 32, an expansion valve (pressure reducing device) 33, a heat exchanger 34, and a fan 35. The four-way valve 32 switches the flow path of the heat transfer medium between cooling and heating. The heat exchanger 34 operates as a condenser during cooling and as an evaporator during heating. The four-way valve 32 and the immersion heat exchanger 6 are connected by heat transfer pipes 36 and 37, which are covered with insulation material.

[0028] A two-point float switch 11 floats on the surface of the water stored in tank 5 (sw), and a float valve 12, which is opened and closed by the float switch 11, is connected to the float switch 11. The float valve 12 is connected to a water tap 18 by a water supply pipe 16. In other words, when the water level in the stored water (sw) drops to a predetermined level, the float switch 11 is turned on, the float valve 12 opens, and water is supplied to tank 5 from the water tap 18. Conversely, when the water level in the stored water (sw) rises to a predetermined level, the float switch 11 is turned off, the float valve 12 closes, and the water supply from the water tap 18 stops. Furthermore, an overflow pipe 17 is located above the stored water sw, and if the stored water sw exceeds the upper limit for any reason, the excess stored water sw is discharged outside through the overflow pipe 17.

[0029] Inside the lower part of tank 5, a water supply pipe 15 is connected to supply the water stored in tank 5 (sw) to the heat exchanger 21 of the fan coil unit 20. The water supply pipe 15 is connected in the following order from the tank 5 side: a gate valve 7, a circulation pump 8, and a gate valve 9. When gate valves 7 and 9 open and the circulation pump 8 is driven, the water stored in tank 5 (sw) is supplied to the heat exchanger 21 through gate valve 7, the circulation pump 8, and gate valve 9. Furthermore, a return pipe 24 is connected to the heat exchanger 21 to return the heat-exchanged water back to the tank 5, and a water spraying device 13 is connected to the end of the return pipe 24 via a control valve 14. As shown in Figure 4, the water spraying device 13 is formed in a long, rod-like shape, and multiple water outlets (not shown) are arranged in the front-to-back direction on its bottom surface. Also, as shown in Figure 5(B), the water spraying device 13 is suspended from the inner surface 55a of the upper wall 55 of the tank 5 by a suspension member 13a. Also, as shown in Figure 5(A), the return pipe 24 is inserted through the rear wall 24 of the tank 5. The water returned from the heat exchanger 21 (hereinafter referred to as return water) rw is sprayed onto the stored water sw from each water outlet of the water spraying device 13. The control valve 14 controls the amount of water flowing through the heat exchanger 21 and the amount of water sprayed by the water spraying device 13.

[0030] As shown in Figures 2 and 3, the circumferential surface of the housing 3 is provided with three air intake ports for the fan coil unit 20 to draw in air. Specifically, an air intake port 4a is provided on the right side 3a of the housing 3, an air intake port 4b is provided on the left side 3b, and an air intake port 4c is provided on the front 3c. Each of the air intake ports 4a, 4b, and 4c is provided with a filter (not shown) to filter out dust and other particles from the air being drawn in. In addition, an air outlet 4d is provided on the front 3c of the housing 3 for the fan 22 (Figure 1) of the fan coil unit 20 to blow air into the room. In this embodiment, the air outlet 4d is provided above the air intake ports 4c. Doors 2a and 2b are provided on the front surface 3c of the housing 3, below the air intake port 4c. Door 2a has a handle 2c, and door 2d has a handle 2d. Doors 2a and 2b can be opened and closed by operating the handles 2c and 2d. Doors 2a and 2b are opened and closed when inserting or removing the tank 5 from the housing 3, or when performing maintenance on the tank 5.

[0031] On the front surface 3c of the housing 3, to the right of the air intake 4c, is an operation panel 14 for operating the air conditioning unit 1. The operation panel 14 includes a cooling switch, a heating switch, a stop switch, a temperature control switch, an airflow control switch, and the like. Each switch is connected to a control circuit (not shown) for controlling the air conditioning unit 1. A door 4e is provided on the front of the housing 3, to the right of the air outlet 4d and air intake 4c, and a handle 4f is provided on the door 4e. The door 4e is opened and closed when performing maintenance or repairs on the control circuit and other components. The right side 3a, the left side 3b, and the front 3c are examples of at least two sides of the present invention.

[0032] [Main components of an immersion heat exchanger] Next, the main components of the immersion-type (submersible) heat exchanger 6 will be explained with reference to Figures 4 and 5. Tank 5 is formed in a rectangular parallelepiped shape (with a rectangular horizontal cross-section) and has a right wall 51, a left wall 52, a rear wall 53, a front wall 54, an upper wall 55, and a lower wall 56. Each wall is covered with insulating material to prevent changes in the temperature of the stored water sw. The upper wall 55 is also openable and serves as the lid of tank 5. The immersion-type heat exchanger 6 is positioned along the inner surface of the right side wall 51 (the inner surface 51a of the right side wall 51), the inner surface of the left side wall 52 (the inner surface 52a of the left side wall 52), and the inner surface of the rear wall 53 (the inner surface 53a of the rear wall 53), but is not positioned along the inner surface of the front wall 54 (the inner surface 54a of the front wall 54). Hereafter, when describing matters common to the inner surface of the right side wall 51a, the inner surface of the left side wall 52a, and the inner surface of the rear wall 53a, the term "inner surface" will be used. As shown in Figure 5(B), the aforementioned watering device 13 is positioned in the front-rear direction below the upper wall 55.

[0033] Furthermore, as shown in Figure 4, the immersion heat exchanger 6 is formed in a shape called a meandering pipe, and meanders in the height direction (up and down direction) of the tank 5. The immersion heat exchanger 6 is continuous, alternately forming folded sections 6a and straight sections 6b. In other words, the immersion heat exchanger 6 has a plurality of straight sections 6b arranged parallel to each other in the horizontal direction, and a plurality of folded sections 6a connecting the upper or lower end of each straight section 6b, and is formed so that the overall shape is meandering. During cooling, a low-temperature, low-pressure liquid flows into the immersion heat exchanger 6 as a heat transfer medium, and during heating, a high-temperature, high-pressure gas flows into the immersion heat exchanger 6 as a heat transfer medium. The heat transfer medium that flows in from the condensing unit 30 via the heat transfer medium pipe 36 flows meanderingly through the immersion heat exchanger 6 and flows out to the condensing unit 30 via the heat transfer medium pipe 37.

[0034] The immersion-type heat exchanger 6 can be formed from roll-bonded plates or pipes. Here, a roll-bonded plate is made by integrating two aluminum plates by rolling, forming a passage through which a heat transfer medium flows inside. Furthermore, as shown in Figure 5, gaps s are formed between the immersion-type heat exchanger 6 and the inner surfaces 51a of the right wall, 52a of the left wall, and 53a of the rear wall. The inner surface 51a of the right wall, the inner surface 52a of the left wall, and the inner surface 53a of the rear wall are examples of at least two inner surfaces of the present invention.

[0035] [Operation during cooling] Next, we will explain the operation of the air conditioning unit 1 during cooling. When the cooling switch on the control panel 14 (Figure 2) is turned on, the air conditioning system 1 starts up, and the compressor 31 (Figure 1) located in the condensing unit 30 of the outdoor unit 1B compresses the heat transfer gas to high temperature and pressure. This gas is sent to the heat exchanger 34 via the four-way valve 32, where the heat exchanger 34 dissipates heat from the received gas by exchanging heat with the outside air using a fan 35, transforming it into a high-pressure liquid. This liquid is then depressurized by the expansion valve 33, transforming it into a low-temperature, low-pressure liquid. This liquid is supplied via the four-way valve 32 and the heat transfer pipe 36 to the immersed heat exchanger 6, which is submerged in the stored water sw of the tank 5, and flows through the inside of the immersed heat exchanger 6 in a meandering manner.

[0036] As a result, the water stored in tank 5 sw is cooled by the immersion-type heat exchanger 6, and the cooled water stored sw is sent by the circulation pump 8 through gate valves 7 and 9 to the heat exchanger 21 of the fan coil unit 20. Then, as the fan 22 rotates, room air is drawn into the fan coil unit 20 through the intake ports 4a, 4b, and 4c (Figure 3). The drawn-in air loses heat as it passes through the heat exchanger 21, and is then blown into the room through the air outlet 4d by the fan 22, cooling the room. In addition, the water stored sw from which heat has been removed in the heat exchanger 21 becomes return water rw and is supplied to the watering device 13, which sprays the return water rw onto the water stored sw.

[0037] The low-temperature, low-pressure liquid supplied to the immersion-type heat exchanger 6 evaporates (vaporizes) by absorbing heat from the stored water sw. This evaporated gas is sent to the condensing unit 30 via the heat transfer medium pipe 37, and then returned to the compressor 31 via the four-way valve 32, where it is compressed into a high-temperature, high-pressure gas. The temperature of the stored water sw corresponds to the room temperature. When the temperature of the stored water sw drops to the set temperature, the compressor 31 in the condensing unit 30 stops. Conversely, when the temperature of the stored water sw exceeds the set temperature, the compressor 31 starts operating. In this way, the temperature of the stored water sw sent from the tank 5 to the heat exchanger 21 of the fan coil unit 20 is controlled, thereby controlling the room temperature.

[0038] [Operation during heating] Next, we will explain the operation of the air conditioning unit 1 during heating. When the heating switch on the control panel 14 (Figure 2) is turned on, the air conditioning system 1 starts up, and the compressor 31 compresses the heat transfer gas to high temperature and pressure. This gas is sent to the immersion type heat exchanger 6 of the indoor unit 1A via the four-way valve 32 and the heat transfer pipe 36. The stored water sw in the tank 5 is heated by the immersion type heat exchanger 6, and this heated stored water (hot water) sw is sent by the circulation pump 8 via the gate valves 7 and 9 to the heat exchanger 21 of the fan coil unit 20. As the fan 22 rotates, indoor air is drawn into the fan coil unit 20 through the intake ports 4a, 4b, and 4c (Figure 3). The drawn-in air is heated as it passes through the heat exchanger 21 and is blown into the room via the air outlet 4d by the fan 22, heating the room. Furthermore, the stored water sw from which heat has been removed in the heat exchanger 21 becomes return water rw and is supplied to the sprinkler 13, which then sprinkles the return water rw onto the stored water sw.

[0039] The high-temperature, high-pressure gas supplied to the immersion-type heat exchanger 6 condenses (liquefies) as heat is absorbed from the stored water sw, changing into a low-temperature, high-pressure liquid. This liquid is sent to the condensing unit 30 via the heat transfer pipe 37, and then to the expansion valve 33 via the four-way valve 32, where it changes into a low-temperature, low-pressure liquid. This liquid flows into the heat exchanger 34, absorbs heat from the outside air, and evaporates (vaporizes). This evaporated gas returns to the compressor again via the four-way valve 32, where it changes into a high-temperature, high-pressure gas.

[0040] [Effects of the Embodiment] (1) In the air conditioning system 1 of the above-described embodiment, the heat exchanger 6 is arranged along three of the four inner surfaces 51a to 54a of the tank 5, so the heat exchange area can be made larger than in a system where the heat exchanger extends in only one direction, and thus the heat exchange efficiency can be increased. Furthermore, it can reduce temperature variations in the water compared to heat exchangers that extend in only one direction.

[0041] (2) Furthermore, according to the air conditioning system 1 of the embodiment described above, the heat exchanger 6 is arranged along the inner surface 53a of the rear wall, the inner surface 51a of the right wall, and the inner surface 52a of the left wall of the tank 5, and is not arranged along the inner surface 54a of the front wall. Therefore, the heat exchanger 6 on each inner surface can be clearly seen from the front, making it easy to perform maintenance or repair on the heat exchanger 6. In particular, if part or all of the front wall 54 is formed of a translucent resin, the heat exchangers 6 on each inner surface can be easily seen, making maintenance or repair of the heat exchangers 6 even easier. Furthermore, if the heat exchanger 6 is positioned along the inner surface 54a of the front wall, the flow inside the tank 5 will become enclosed, potentially obstructing the convection path. However, by not positioning the heat exchanger 6 along the inner surface 54a of the front wall, convection inside the tank 5 becomes more active, thereby increasing the heat exchange efficiency.

[0042] (3) Furthermore, according to the air conditioning system 1 of the embodiment described above, since the heat transfer medium pipe 6 meanders in the vertical direction, when a low-temperature heat transfer medium flows through the heat transfer medium pipe during cooling, the water surrounding the heat transfer medium pipe 6 is cooled, its specific gravity increases, and a downward flow occurs. This downward flow induces natural convection, causing circulation throughout the tank 5, thus reducing temperature unevenness in the vertical direction. Furthermore, when a high-temperature heat transfer medium flows through the heat transfer medium pipe during heating, the water surrounding the heat transfer medium pipe 6 is heated, its specific gravity decreases, and an upward flow (chimney flow) is generated. This upward flow induces natural convection, causing circulation throughout the tank 5, thus reducing temperature variations in the vertical direction.

[0043] (4) Furthermore, according to the air conditioning device 1 of the embodiment described above, since gaps s are formed between the inner surfaces 51a to 53a along which the heat transfer pipe 6 is arranged and the heat transfer pipe 6, the water sw stored in the tank 5 can flow around the outer circumference of the heat transfer pipe 6 from all directions, making it easy for natural convection to occur. Therefore, since circulation is more likely to occur throughout tank 5, temperature variations in the vertical direction can be further reduced. Furthermore, since the entire circumference of the heat transfer tube 6 is in contact with water, the heat transfer area can be effectively utilized, thereby increasing the heat exchange efficiency.

[0044] (5) Furthermore, according to the air conditioning device 1 of the embodiment described above, the return water rw that has returned from the fan coil unit 20 can be sprayed onto the stored water sw in the tank 5, so that the return water rw can be distributed and supplied over a wide surface of the stored water sw. Therefore, since the return water rw from the fan coil unit 20 can be rapidly mixed with the stored water sw, the heat of the return water rw is diffused uniformly, further reducing temperature unevenness.

[0045] (6) Furthermore, according to the air conditioning device 1 of the embodiment described above, since intake ports 4a to 4c for the fan coil unit 20 to draw in air are provided on the three circumferential surfaces 3a to 3c of the housing 3 in which the fan coil unit 20 is installed, the intake efficiency can be increased, and thus the air conditioning efficiency can be increased.

[0046] (7) Furthermore, according to the air conditioning system 1 of the embodiment described above, since the tank 5 is located inside the room, the influence of outside air on the water temperature is reduced, and the temperature difference between the inlet and outlet of the heat exchanger 21 of the fan coil unit 20 can be increased, thereby increasing the cooling capacity.

[0047] (8) Furthermore, according to the air conditioning system 1 of the embodiment described above, the condensing unit 30 located outside and the immersion type heat exchanger 6 of the tank 5 located inside are connected by heat transfer pipes 36 and 37. Compared to intake and drainage pipes, the pipe radius is smaller and the pipe is lighter. Also, the bending radius is smaller and the number of joints is reduced. In other words, it is easier to install and offers greater flexibility in piping. Furthermore, it makes it easier to renovate existing systems.

[0048] (9) Furthermore, according to the air conditioning system 1 of the embodiment described above, since the tank 5 is located below the fan coil unit 20, the horizontal width of the indoor unit 1A can be reduced, thereby increasing the flexibility of the installation location of the indoor unit 1A.

[0049] (10) Furthermore, according to the air conditioning system 1 of the embodiment described above, the heat exchanger 6 is not located in the center of the tank 5, making it easy to access the inside of the tank 5 and thus easy to perform maintenance on the heat exchanger 6.

[0050] (11) Furthermore, according to the air conditioning device 1 of the embodiment described above, since the horizontal cross-sectional shape of the housing 3 is rectangular, it can be placed in the corner of a room, thus increasing the flexibility of the installation location.

[0051] (12) As described above, the air conditioning system 1 of the embodiment can provide an air conditioning system that can increase the heat exchange efficiency of the immersion type heat exchanger 6 and reduce temperature unevenness of the stored water sw in the tank 5.

[0052] [Other embodiments] (1) The heat exchanger 6 may also be positioned along two surfaces, the inner surface 51a of the right wall and the inner surface 53a of the rear wall, or along two surfaces, the inner surface 52a of the left wall and the inner surface 53a of the rear wall, or along two surfaces, the inner surface 51a of the right wall and the inner surface 52a of the left wall. (2) Tank 5 may be a pentagonal prism or a hexagonal prism, or any other shape besides a rectangular prism. Also, although Tank 5 is a rectangular prism or a cylinder, the inner surface of Tank 5 may be a pentagonal prism or a hexagonal prism, or any other shape besides a rectangular prism.

[0053] (3) As shown in Figure 6, the heat exchanger 6 may have a meandering shape in the horizontal direction. (4) The sprinkler devices 13 may be arranged in the left-right direction, or multiple devices may be arranged. Also, the sprinkler devices 13 may be in a cross shape or a grid shape in plan view. (5) Instead of using the water tap 18, groundwater such as well water may be used. (6) According to the present invention, the cooling capacity can be increased compared to conventional designs, and the condensing unit 30 can be connected to multiple greenhouses or rooms. Furthermore, in this case, it is only necessary to branch the heat transfer pipes 36 and 37 connected to the condensing unit 30 to each greenhouse or room. Therefore, as mentioned above, compared to the case where the tank 5 is placed outdoors, the difficulty of installation is lower and the flexibility of the piping is greater. In addition, existing modifications become easier. [Explanation of Symbols]

[0054] 1. Air conditioning system 1A Indoor unit 1B...Outdoor unit 3. Housing 3a...Right side 3b...Left side 3c...Front 4a.. Air intake 4b. Air intake 4c ··Air intake 5 tanks 6...Immersion heat exchanger 13. Sprinkler system 20...Fan coil unit 21...heat exchanger 30. Condensing Unit 31. Compressor 32...4-way valve 33. Expansion valve 34...heat exchanger 51...right side wall 51a...Right side wall inner surface 52...left side wall 52a ··Inner surface of left wall 53...back wall 53a...Inner surface of rear wall 54...Front wall 54a...Inner surface of front wall 55... Upper wall 56... Lower wall

Claims

1. A tank for storing water, A heat exchanger immersed in the water stored in the aforementioned tank, A condensing unit that supplies a heat transfer medium to the heat exchanger, An air conditioning system comprising a fan coil unit to which water stored in the tank is supplied, The tank has at least four inner surfaces along its inner circumference, The heat exchanger is, An air conditioning device characterized in that it is arranged along at least two of the four inner surfaces.

2. The aforementioned tank is The horizontal cross-sectional shape is rectangular, and it has four inner surfaces consisting of the inner surface of the front wall, the inner surface of the rear wall, the inner surface of the right wall, and the inner surface of the left wall. The heat exchanger is, The air conditioning device according to claim 1, characterized in that it is arranged along the inner surface of the rear wall, the inner surface of the right wall, and the inner surface of the left wall, but is not arranged along the inner surface of the front wall.

3. The heat exchanger is, It has a heat transfer tube through which the heat transfer medium flows, The air conditioning device according to claim 1 or 2, characterized in that the heat transfer tube is meandering in the vertical direction.

4. The air conditioning device according to claim 1 or 2, characterized in that a gap is formed between the inner surface along which the heat transfer pipe is arranged and the heat transfer pipe.

5. The air conditioning system according to claim 1 or 2, characterized in that it is provided with a sprinkler device that sprinkles water returned from the fan coil unit onto the water stored in the tank.

6. It has a housing in which the aforementioned fan coil unit is installed inside, An air outlet is provided at a predetermined location on the circumferential surface of the housing for the fan coil unit to blow air into the room. The air conditioning device according to claim 1 or 2, characterized in that at least two surfaces of the circumferential surface of the housing are provided with air intake ports for the fan coil unit to draw in air.

7. The tank is located below the fan coil unit. The fan coil unit and the tank are located inside the room. The air conditioning system according to claim 1 or 2, characterized in that the condensing unit is located outside the room.

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