Air conditioning system

Abstract

To provide an air conditioning system with improved user convenience.SOLUTION: An air conditioning system comprises: an outdoor unit (10); a first indoor unit (51); a leakage sensor (75) that detects leakage of a refrigerant; and a plurality of shut-off valve devices (30) that is arranged in parallel to a first refrigerant pipe (21) connecting the outdoor unit (10) and the first indoor unit (51), and closes when the leakage sensor (75) detects the leakage of the refrigerant.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to air conditioning systems. [Background technology]

[0002] 2. Description of the Related Art Air conditioners are known that have a shutoff valve that shuts off the flow of refrigerant in order to reduce the amount of leakage when a refrigerant leak is detected. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-9267 Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present invention is to provide an air conditioning system that improves user convenience. [Means for solving the problem]

[0005] The air conditioning system of the present disclosure includes an outdoor unit, an indoor unit, a leak sensor that detects refrigerant leakage, and a plurality of shut-off valves that are arranged in parallel in refrigerant piping connecting the outdoor unit and the indoor unit and that close when the leak sensor detects a refrigerant leakage. [Effects of the Invention]

[0006] In the air conditioning system of the present disclosure, when the air conditioning capacity of the indoor unit is high, it is necessary to change the diameter of the refrigerant piping to ensure the refrigerant flow rate, and a shut-off valve corresponding to the diameter of the refrigerant piping must be provided. However, by arranging multiple shut-off valves in parallel, there is no longer a need to provide a shut-off valve corresponding to a refrigerant piping with a large diameter, improving user convenience. [Brief explanation of the drawings]

[0007] [Figure 1] Diagram showing the system configuration of an air conditioning system [Figure 2] Block diagram showing the configuration of the first parent unit shutoff valve device [Figure 3] Block diagram showing the configuration of the No. 1-1 slave shutoff valve device [Figure 4] Block diagram showing the indoor unit configuration [Figure 5] Flowchart showing a first operation of the first parent unit shutoff valve device [Figure 6] Flowchart showing a first operation of the first parent unit shutoff valve device [Figure 7] Flowchart showing a first operation of the first-first slave shutoff valve device [Figure 8] Flowchart showing a second operation of the first parent unit shutoff valve device [Figure 9] Flowchart showing second operation of the first-second slave shutoff valve device [Figure 10] FIG. 1 shows another configuration of an air conditioning system. [Figure 11] FIG. 10 is a diagram showing an example of a circuit board configuration of a first parent unit shutoff valve device. [Figure 12] FIG. 1 is a diagram showing the configuration of a communication line I / F provided in an indoor unit, a first parent-unit shutoff valve device, and a first child-unit shutoff valve device. DETAILED DESCRIPTION OF THE INVENTION

[0008] (Findings that formed the basis of this disclosure) As the air conditioning capacity of an indoor unit increases, it becomes necessary to ensure a sufficient flow of refrigerant to the indoor unit, so a refrigerant pipe with a larger diameter must be installed, and a separate shutoff valve corresponding to this diameter size must also be prepared.In other words, a separate shutoff valve corresponding to the diameter of the refrigerant pipe must be prepared for each air conditioning capacity of the indoor unit, which is a hassle for users. However, the inventors discovered that by arranging multiple shut-off valves in parallel on the refrigerant piping, it is possible to ensure the refrigerant flow rate to the indoor unit while reducing the hassle of having to prepare separate shut-off valves of different sizes, and in order to solve this problem, they came up with the subject matter of the present disclosure. Therefore, the present disclosure aims to improve user convenience while ensuring optimal refrigerant flow rate and suppressing refrigerant leakage, even in air conditioning systems equipped with indoor units with high air conditioning capacity.

[0009] Hereinafter, embodiments will be described in detail with reference to the drawings. However, in some cases, more detailed explanation than necessary may be omitted. For example, detailed explanation of already well-known matters or redundant explanation of substantially the same configuration may be omitted. The accompanying drawings and the following description are provided to enable those skilled in the art to fully understand the present disclosure, and are not intended to limit the subject matter described in the claims.

[0010] [1: Embodiment 1] [1-1: Composition]

[0011] FIG. 1 is a diagram showing the system configuration of an air conditioning system 1 according to the first embodiment. The air conditioning system 1 comprises an outdoor unit 10 installed outdoors and multiple indoor units 50 installed in rooms to be air-conditioned, and the outdoor unit 10 and the indoor units 50 are connected by refrigerant piping 20. The refrigerant piping 20 is a pipe that serves as a flow path for the refrigerant. The outdoor unit 10, the indoor units 50, and the refrigerant piping 20 form a refrigerant circuit through which the refrigerant circulates.

[0012] The outdoor unit 10 includes a compressor, a four-way valve, an outdoor heat exchanger, and an expansion valve. The compressor compresses the refrigerant. The four-way valve changes the flow path of the refrigerant between cooling and heating operation. The outdoor heat exchanger exchanges heat between the outdoor air and the refrigerant. The expansion valve reduces the pressure of the refrigerant.

[0013] Indoor unit 50 is installed, for example, in a room of an office, etc. Indoor unit 50 includes indoor heat exchanger 515 and indoor fan 517. By driving indoor fan 517, indoor unit 50 exchanges heat between the refrigerant flowing inside indoor heat exchanger 515 and the air, and adjusts the room temperature of the room to be air-conditioned by blowing out the air that has undergone heat exchange from an air outlet (not shown).

[0014] 1 shows a configuration in which the air conditioning system 1 is equipped with two indoor units 50, a first indoor unit 51 and a second indoor unit 53, but the air conditioning system 1 may be equipped with any number of indoor units 50, and may be equipped with three or more indoor units 50. When referring to the first indoor unit 51 and the second indoor unit 53 collectively, they are referred to as indoor units 50.

[0015] The outdoor unit 10 and the two indoor units 50, the first indoor unit 51 and the second indoor unit 53, are each connected by refrigerant piping 20. The refrigerant piping 20 includes a gas side refrigerant piping and a liquid side refrigerant piping. The refrigerant piping 20 is a piping in which the gas side refrigerant piping and the liquid side refrigerant piping are provided as an integrated unit. The gas side refrigerant piping is a piping that serves as a flow path for vaporized refrigerant, and the liquid side refrigerant piping is a piping that serves as a flow path for liquefied refrigerant.

[0016] Of the refrigerant pipes 20, the refrigerant pipes 20 connected to the first indoor unit 51 are referred to as first refrigerant pipes 21, and the refrigerant pipes 20 connected to the second indoor unit 53 are referred to as second refrigerant pipes .

[0017] A portion of the first refrigerant pipe 21 branches into four: a first branch refrigerant pipe 21A, a second branch refrigerant pipe 21B, a third branch refrigerant pipe 21C, and a fourth branch refrigerant pipe 21D. A shutoff valve device 30 is provided in each of the four branched refrigerant pipes 20: the first branch refrigerant pipe 21A, the second branch refrigerant pipe 21B, the third branch refrigerant pipe 21C, and the fourth branch refrigerant pipe 21D. The shutoff valve device 30 provided in the first branch refrigerant pipe 21A is referred to as a first parent unit shutoff valve device 31A. The shutoff valve device 30 provided in the second branch refrigerant pipe 21B is referred to as a 1-1 child unit shutoff valve device 33A. The shutoff valve device 30 provided in the third branch refrigerant pipe 21C is referred to as a 1-2 child unit shutoff valve device 33B. The shutoff valve device 30 provided in the fourth branch refrigerant pipe 21D is referred to as a 1-3 child unit shutoff valve device 33C.

[0018] The first parent shutoff valve device 31A, the 1-1st child shutoff valve device 33A, the 1-2nd child shutoff valve device 33B, and the 1-3rd child shutoff valve device 33C are arranged in parallel. For example, if the air conditioning capacity of the first indoor unit 51 is high, it is necessary to change the refrigerant piping to one with a larger diameter to ensure a sufficient refrigerant flow rate. For this reason, it is necessary to prepare a shutoff valve device 30 to be disposed on the refrigerant piping 20 that corresponds to the diameter of the refrigerant piping 20. In this embodiment, a part of the first refrigerant pipe 21 is branched into four, a first branch refrigerant pipe 21A, a second branch refrigerant pipe 21B, a third branch refrigerant pipe 21C, and a fourth branch refrigerant pipe 21D, and a shutoff valve device 30 is disposed in each of the four branched branch refrigerant pipes 21A, 21B, 21C, and 21D. This ensures a sufficient flow rate of refrigerant supplied to the first indoor unit 51. Furthermore, since there is no need to separately prepare a shutoff valve device 30 for refrigerant pipes with a large diameter, user convenience can be improved.

[0019] Similarly, a portion of the second refrigerant piping 23 branches into two, a first branch refrigerant piping 23A and a second branch refrigerant piping 23B. A shutoff valve device 30 is disposed in each of the two branched refrigerant piping 20, the first branch refrigerant piping 23A and the second branch refrigerant piping 23B. The shutoff valve device 30 disposed in the first branch refrigerant piping 23A is referred to as a second parent unit shutoff valve device 31B. The shutoff valve device 30 disposed in the second branch refrigerant piping 23B is referred to as a 2-1 child unit shutoff valve device 33D.

[0020] The master unit shutoff valve device 31 is a device that is connected to the indoor unit 50 by a remote control wire 60. In Fig. 1, the remote control wire 60 is shown by a dashed line. Specifically, the first master unit shutoff valve device 31A is connected to the first indoor unit 51 by a first remote control wire 61, and the second master unit shutoff valve device 31B is connected to the second indoor unit 53 by a second remote control wire 63. The first remote control wire 61 and the second remote control wire 63 are collectively referred to as the remote control wire 60. The first parent unit shutoff valve device 31A is a device that communicates directly with the first indoor unit 51 via a first remote control line 61. The second parent unit shutoff valve device 31B is a device that communicates directly with the second indoor unit 53 via a second remote control line 63.

[0021] The slave shutoff valve device 33 is a device that is daisy-chained to the master shutoff valve device 31 via a communication line 40. In Fig. 1, the communication line 40 is indicated by a dashed line. The first parent shutoff valve device 31A is daisy-chained with the first-first child shutoff valve device 33A, the first-second child shutoff valve device 33B, and the first-third child shutoff valve device 33C. The first parent shutoff valve device 31A is connected to the first parent shutoff valve device 31A via a communication line 40, the first-second child shutoff valve device 33B is connected to the first parent shutoff valve device 31A via a communication line 40, and the first-third child shutoff valve device 33C is connected to the first parent shutoff valve device 31A via a communication line 40.

[0022] The second master cutoff valve device 31B is daisy-chained with the second-1st slave cutoff valve device 33D via a communication line 40.

[0023] Furthermore, in addition to the first parent unit shutoff valve device 31A and the first indoor unit 51, a first remote control 71 and a first alarm device 73 are connected to the first remote control line 61. The first parent unit shutoff valve device 31A, first indoor unit 51, first remote control 71, and first alarm 73 connected to the first remote control line 61 are recognized as being in the same group. A group refers to a collection of devices that are the subject of control. These devices that belong to the same group can send and receive data via the first remote control line 61, and the communication status is managed.

[0024] The remote control cable 60 has a limit to the number of indoor units 50 and shutoff valve devices 30 that can be recognized as part of the same group. For example, up to eight indoor units can be connected to the same remote control cable. For this reason, in this embodiment, only the first master shutoff valve device 31A is connected to the first indoor unit 51 via the first remote control cable 61, and the 1-1 slave shutoff valve device 33A, 1-2 slave shutoff valve device 33B, and 1-3 slave shutoff valve device 33C are daisy-chain connected to the first master shutoff valve device 31A via the communication cable 40. With this configuration, even if the air conditioning system 1 is provided with multiple slave shutoff valve devices 33, the number of indoor units 50 that can be connected via the remote control cable 60 can be ensured.

[0025] The first remote control 71 is a device that accepts operations such as switching between heating and cooling, and setting the temperature of the first indoor unit 51.

[0026] The first alarm 73 is equipped with a leak sensor 75. The leak sensor 75 is a sensor that detects refrigerant leakage. The leak sensor 75 outputs a signal indicating that refrigerant has leaked when the condition that the concentration of refrigerant around it exceeds a predetermined value is met. When the leak sensor 75 outputs a signal, the first alarm 73 displays a predetermined warning display indicating that refrigerant has leaked and / or outputs an alarm sound.

[0027] Similarly, a second remote control 81 and a second alarm 83 are connected to the second indoor unit 53 via a second remote control line 63, respectively.

[0028] FIG. 2 is a block diagram showing the configuration of the first parent unit cutoff valve device 31A. The first parent unit shutoff valve device 31A includes a communication line interface 311A, a remote control line interface 313A, a shutoff valve 315A, and a parent unit control device 320A. Hereinafter, the interface will be abbreviated as I / F.

[0029] The communication line I / F 311A is an interface that connects to the communication line 40. The communication line I / F 311A includes a connection terminal that complies with a predetermined communication standard and an I / F circuit.

[0030] The remote control line I / F 313A is an interface for connecting a remote control line, and includes a connection terminal conforming to a predetermined communication standard and an I / F circuit.

[0031] The shutoff valve 315A is provided in the refrigerant piping 20 and is controlled to an open or closed state by the master controller 320A. When the shutoff valve 315A is open, refrigerant flows through the refrigerant piping 20, and when the shutoff valve 315A is closed, the refrigerant flowing through the refrigerant piping 20 is shut off. For example, the master controller 320A controls the shutoff valve 315A to an open state in a normal state. The normal state is a state in which the leak sensor 75 does not detect a refrigerant leak, there is no communication abnormality in the first indoor unit 51 or the shutoff valve device 30, and the first indoor unit 51 and the shutoff valve device 30 operate normally. Furthermore, the master controller 320A controls the shutoff valve 315 to a closed state when the leak sensor 75 detects a refrigerant leak, when communication with the shutoff valve device 30 is disabled, or when the shutoff valve device 30 is inspected.

[0032] The master control device 320A is a computer device that includes a master storage unit 321A and a master processor 325A.

[0033] The parent device storage unit 321A includes memories such as a ROM (Read Only Memory) and a RAM (Random Access Memory).

[0034] The master device storage unit 321A stores a control program 322A executed by the master device processor 325A and slave device identification information 323A. The slave unit identification information 323A is identification information that uniquely identifies each of the multiple slave unit cutoff valve devices 33 that belong to the group.

[0035] The parent processor 325A is an arithmetic processing device including a CPU (Central Processing Unit) and an MPU (Micro Processing Unit). The parent processor 325A may be configured with a single processor or multiple processors.

[0036] FIG. 3 is a block diagram showing the configuration of the 1-1 slave cutoff valve device 33A. The 1-1st slave unit cutoff valve device 33A includes a communication line I / F 331A, a cutoff valve 333A, and a slave unit control device 340A. The configurations of the communication line I / F 331A and the cutoff valve 333A are the same as those of the communication line I / F 311A and the cutoff valve 315A provided in the first parent unit cutoff valve device 31A, and therefore a description thereof will be omitted.

[0037] The slave unit control device 340A is a computer device including a slave unit storage unit 341A and a slave unit processor 345A.

[0038] The slave device storage unit 341A includes a memory such as a ROM or a RAM.

[0039] The slave unit storage unit 341A stores a control program 342A executed by the slave unit processor 345A and slave unit identification information 343A. The slave unit identification information 343A is identification information that identifies the 1-1 slave unit cutoff valve device 33A itself.

[0040] The slave device processor 345A is an arithmetic processing unit including a CPU and an MPU. The slave device processor 345A may be configured with a single processor, or may be configured with multiple processors.

[0041] FIG. 4 is a block diagram showing the configuration of the indoor unit 50. The indoor unit 50 includes a communication line I / F 511, a remote control line I / F 513, an indoor heat exchanger 515, and an indoor fan 517. The configurations of the communication line I / F 511 and the remote control line I / F 513 are the same as the communication line I / F 311A and the remote control line I / F 313A provided in the first parent unit cutoff valve device 31A, and therefore description thereof will be omitted.

[0042] The indoor heat exchanger 515 exchanges heat between the refrigerant supplied from the outdoor unit 10 through the refrigerant pipe 20 and the indoor air. The indoor fan 517 takes in indoor air into the indoor unit 50, and sends the air that has been heat exchanged by the indoor heat exchanger 515 into the room to be air-conditioned.

[0043] The indoor unit control device 520 is a computer device that includes an indoor unit storage unit 521 and an indoor unit processor 525.

[0044] The indoor unit storage unit 521 includes a memory such as a ROM or a RAM.

[0045] The indoor unit storage unit 521 stores a control program 523 that is executed by the indoor unit processor 525.

[0046] The indoor unit processor 525 is an arithmetic processing device equipped with a CPU and an MPU. The indoor unit processor 525 may be configured with a single processor, or may be configured with multiple processors.

[0047] The first operation executed by the first master unit shutoff valve device 31A, the plurality of slave unit shutoff valve devices 33, and the first indoor unit 51 will be described below. The first action is an action to close the shutoff valves of the first parent unit shutoff valve device 31A and the parent unit shutoff valve device 33 when a child unit shutoff valve device 33 that is unable to communicate is detected, or when communication between the first indoor unit 51 and the first parent unit shutoff valve device 31A becomes impossible. Also, in the first action, air conditioning operation of the first indoor unit 51 is prohibited.

[0048] The master control device 320A performs data communication with the first indoor unit 51 connected by the first remote control line 61 and the daisy-chained first-first slave shutoff valve device 33A. The master unit controller 320A monitors the communication status of the first indoor unit 51 and the communication status of the first-first slave unit shutoff valve device 33A, the first-second slave unit shutoff valve device 33B and the first-third slave unit shutoff valve device 33C.

[0049] The master control device 320A transmits a request for obtaining slave identification information to the subsequent first-first slave cutoff valve device 33A at predetermined intervals. When the 1-1 child unit shutoff valve device 33A receives a request to acquire child unit identification information from the parent unit controller 320A, it transmits child unit identification information 343A of the 1-1 child unit shutoff valve device 33A to the parent unit controller 320A. The 1-1 child unit shutoff valve device 33A also transmits the request to acquire the child unit identification information received from the parent unit controller 320A to the subsequent 1-2 child unit shutoff valve device 33B.

[0050] When the 1-2 child unit shut-off valve device 33B receives a request to acquire child unit identification information from the 1-1 child unit shut-off valve device 33A, it transmits child unit identification information 343B of the 1-2 child unit shut-off valve device 33B to the 1-1 child unit shut-off valve device 33A. The 1-1 child unit shut-off valve device 33A transmits the received child unit identification information 343B of the 1-2 child unit shut-off valve device 33B to the parent unit control device 320A. The first-second slave shutoff valve device 33B also transmits a request to acquire the slave identification information received from the first-first slave shutoff valve device 33A to the subsequent first-third slave shutoff valve device 33C.

[0051] When the 1-3 slave unit shutoff valve device 33C receives a request to acquire slave unit identification information from the 1-2 slave unit shutoff valve device 33B, it transmits slave unit identification information 343C of the 1-3 slave unit shutoff valve device 33C to the 1-2 slave unit shutoff valve device 33B. The slave unit identification information 343C of the 1-3 slave unit shutoff valve device 33C is transmitted to the master unit control device 320A via the 1-2 slave unit shutoff valve device 33B and the 1-1 slave unit shutoff valve device 33A.

[0052] The master unit control device 320A detects slave unit shutoff valve devices 33 with which communication is not possible by comparing the acquired slave unit identification information 343 with the slave unit identification information 323A stored in the master unit storage unit 321A. For example, if communication between the first master unit shutoff valve device 31A and the first-first slave unit shutoff valve device 33A becomes impossible, the master unit control device 320A cannot acquire the slave unit identification information 343A, 343B, and 343C. Furthermore, if communication between the first-first slave unit shutoff valve device 33A and the first-second slave unit shutoff valve device 33B becomes impossible, the master unit control device 320A cannot acquire the slave unit identification information 343B and 343C.

[0053] When the master unit control device 320A detects a slave unit shutoff valve device 33 with which communication is not possible, it sends an instruction to the subsequent 1-1 slave unit shutoff valve device 33A to close the shutoff valve 333A. The master unit control device 320A also closes the shutoff valve 315 of the first master unit shutoff valve device 31A. When the master unit control device 320A detects a slave unit shutoff valve device 33 with which communication is not possible, it also instructs the first indoor unit 51 to prohibit air conditioning operation.

[0054] When the 1-1 slave shut-off valve device 33A receives a closure instruction from the first master shut-off valve device 31A, it closes the shut-off valve 333A of the 1-1 slave shut-off valve device 33A, and if communication with the subsequent 1-2 slave shut-off valve device 33B is possible, it sends an instruction to the 1-2 slave shut-off valve device 33B to close the shut-off valve 333B.

[0055] For example, it is assumed that communication with the first-second slave cutoff valve device 33B is in a communication disabled state. If the 1-2 slave unit shutoff valve device 33B does not receive an acquisition request or instruction from the preceding 1-1 slave unit shutoff valve device 33A for a preset time or longer, it determines that communication with the 1-1 slave unit shutoff valve device 33A is not possible. When the 1-2 slave unit shutoff valve device 33B detects that communication is not possible, it closes the shutoff valve 333B of the 1-2 slave unit shutoff valve device 33B. Furthermore, if the 1-2 slave unit shutoff valve device 33B is able to communicate with the following 1-3 slave unit shutoff valve device 33C, it sends an instruction to the 1-3 slave unit shutoff valve device 33C to close the shutoff valve 333C. This causes the shutoff valves 333 of all slave unit shutoff valve devices 33 to be closed.

[0056] Next, the second operation will be described. In the second operation, when a communication-disabled slave unit shutoff valve device 33 is detected, the shutoff valves 315A, 333 of the first master unit shutoff valve device 31A that is capable of communication and the slave unit shutoff valve device 33 that is capable of communication with the first master unit shutoff valve device 31A or the preceding slave unit shutoff valve device 33 are kept open without being closed. Furthermore, the slave unit shutoff valve device 33 that is unable to communicate closes its own shutoff valve 333. Furthermore, in the second operation, the first master unit shutoff valve device 31A notifies the first indoor unit 51 of a communication abnormality in the slave unit shutoff valve device 33, but the first indoor unit 51 continues air-conditioning operation. By closing the shutoff valve 333 of the slave unit shutoff valve device 33 that is unable to communicate and by keeping the shutoff valve 333 of the slave unit shutoff valve device 33 that is capable of communication open, a significant decrease in user comfort can be prevented until maintenance is performed on the slave unit shutoff valve that is unable to communicate. In addition, in the second operation, if communication between the first indoor unit 51 and the first parent unit shut-off valve device 31A becomes impossible, the shut-off valves of the first parent unit shut-off valve device 31A and the child unit shut-off valve device 33 are closed, and air conditioning operation of the first indoor unit 51 is prohibited.

[0057] [1-2: 1st action] FIG. 5 is a flowchart showing a first operation of the first parent unit cutoff valve device 31A. In particular, FIG. 5 is a flowchart showing the operation when the first master shutoff valve device 31A determines the communication state with the slave shutoff valve device 33. The first operation of the master unit shutoff valve device 31 will be described with reference to the flowchart shown in FIG. First, the master unit control device 320A determines whether a preset time has elapsed (step S1). The preset time may be, for example, the time elapsed since the previous time measurement was completed, or the time elapsed since the previous request for acquiring slave unit identification information was transmitted to the slave unit shutoff valve device 33.

[0058] If the preset time has not elapsed (step S1 / NO), the master unit control device 320A waits until the preset time has elapsed. If the preset time has elapsed (step S1 / YES), the master unit control device 320A transmits a request to acquire slave unit identification information to the 1-1 slave unit shutoff valve device 33A (step S2). When the 1-1 slave unit shutoff valve device 33A receives the request to acquire slave unit identification information from the master unit control device 320A, it transmits the request to acquire slave unit identification information to the 1-2 slave unit shutoff valve device 33B in the subsequent stage. Similarly, when the 1-2 slave unit shutoff valve device 33B receives the request to acquire slave unit identification information from the 1-1 slave unit shutoff valve device 33A, it transmits the request to acquire slave unit identification information to the 1-3 slave unit shutoff valve device 33C in the subsequent stage.

[0059] Next, the master control device 320A determines whether or not the slave identification information has been received (step S3). For example, when the 1-1 slave unit shutoff valve device 33A receives a request to acquire slave unit identification information 343 from the master unit control device 320A, it transmits the slave unit identification information 343A of the 1-1 slave unit shutoff valve device 33A to the first master unit shutoff valve device 31A. Furthermore, when the 1-1 slave unit shutoff valve device 33A receives slave unit identification information from the subsequent 1-2 slave unit shutoff valve device 33B, it transmits the received slave unit identification information to the first master unit shutoff valve device 31A.

[0060] If the parent device control device 320A has not received the child device identification information (step S3 / NO), it determines whether a predetermined time has elapsed since the acquisition request was sent in step S2S (step S4). If the parent device control device 320A has not elapsed the predetermined time since the acquisition request was sent (step S4 / NO), it returns to the determination in step S3.

[0061] When a predetermined time has elapsed since sending the acquisition request (step S4 / YES), the master unit control device 320A determines that communication between the first master unit shutoff valve device 31A and the 1-1st slave unit shutoff valve device 33A is unavailable. The master unit control device 320A then controls the shutoff valve 315A to a closed state (step S7). Thereafter, the master unit control device 320A determines whether communication with the first indoor unit 51 is available (step S8).

[0062] If communication with the first indoor unit 51 is not possible (step S8 / NO), the master control device 320A ends this processing flow. If communication with the first indoor unit 51 is possible (step S8 / YES), the master control device 320A transmits a first abnormality code to the first indoor unit 51 (step S9). The first abnormality code is a code indicating that an abnormality has occurred in the shutoff valve devices 30 and that all shutoff valve devices 30 have been closed. When the first indoor unit 51 receives the first abnormality code from the master control device 320A, it prohibits air conditioning operation and transmits the first abnormality code to the first remote control 71. When the first remote control 71 receives the first abnormality code, it displays that the state of the first indoor unit 51A has become a state in which air conditioning operation is prohibited and that a communication abnormality has occurred in the shutoff valve devices 30.

[0063] Furthermore, when the master unit control device 320A receives the slave unit identification information 343 (step S3 / YES), it determines whether or not there is any slave unit identification information 343 that could not be acquired (step S5). The master unit control device 320A compares the acquired slave unit identification information 343 with the slave unit identification information 323 stored in the master unit storage unit 321 to determine whether or not there is any slave unit identification information 343 that could not be acquired.

[0064] If there is any child unit identification information 343 that the parent unit control device 320A was unable to acquire (step S5 / YES), it transmits an instruction to the 1-1 child unit shutoff valve device 33A to close the shutoff valve 333 (step S6). The 1-1 child unit shutoff valve device 33A that has received the close instruction controls its own shutoff valve 333 to a closed state, and, if communication with the subsequent 1-2 child unit shutoff valve device 33B is possible, transmits an instruction to the subsequent 1-2 child unit shutoff valve device 33B to close the shutoff valve 333.

[0065] Next, the master unit control device 320A closes the shutoff valve 315 of the first master unit shutoff valve device 31A (step S7). Thereafter, the master unit control device 320A determines whether communication with the first indoor unit 51 is possible (step S8). If communication with the first indoor unit 51 is not possible (step S8 / NO), the master unit control device 320A ends this processing flow.

[0066] Furthermore, if communication with the first indoor unit 51 is possible (step S8 / YES), the master control device 320A transmits a first abnormality code to the first indoor unit 51 (step S9). When the first indoor unit 51 receives the first abnormality code from the master control device 320A, it prohibits air conditioning operation and transmits the first abnormality code to the first remote control 71. When the first remote control 71 receives the first abnormality code, it displays that the state of the first indoor unit 51A has become a state in which air conditioning operation is prohibited, and that a communication abnormality has occurred in the shut-off valve device 30.

[0067] FIG. 6 is a flowchart showing a first operation of the first parent unit cutoff valve device 31A. 6 is a flowchart showing the operation of the first parent unit shutoff valve device 31A when determining the state of communication with the first indoor unit 51. A first operation of the parent unit shutoff valve device 31 will be described with reference to the flowchart shown in FIG.

[0068] The master unit control device 320A determines whether a preset time has elapsed since the last time it determined whether communication with the first indoor unit 51 is possible (step S11). If the preset time has not elapsed (step S11 / NO), the master unit control device 320A waits until the preset time has elapsed.

[0069] When a preset time has elapsed (step S11 / YES), the master unit control device 320A determines whether or not communication with the first indoor unit 51 is possible (step S12). If communication with the first indoor unit 51 is possible (step S12 / YES), the master unit control device 320A ends this processing flow.

[0070] When communication with the first parent unit shutoff valve device 31A becomes impossible, the first indoor unit 51 prohibits air conditioning operation and transmits a first abnormality code to the first remote control 71. When the first remote control 71 receives the first abnormality code, it displays that the state of the first indoor unit 51A has become a state in which air conditioning operation is prohibited, and that a communication abnormality has occurred in the shutoff valve device 30.

[0071] If communication with the first indoor unit 51 is unavailable (step S12 / NO), the master unit control device 320A sends a command to the 1-1 slave unit shutoff valve device 33A to shut off the shutoff valve 333A (step S13). Thereafter, the master unit control device 320A closes the shutoff valve 315A of the first master unit shutoff valve device 31A (step S14), and ends this processing flow.

[0072] FIG. 7 is a flowchart showing a first operation of the 1-1 slave cutoff valve device 33A. Next, we will explain the first operation of the slave unit shutoff valve device 33. Since the operations of the 1-1 slave unit shutoff valve device 33A to the 1-3 slave unit shutoff valve device 33C are substantially the same, the operation of the 1-1 slave unit shutoff valve device 33A will be explained below as a representative, and explanations of the operations of the other slave unit shutoff valve devices 33 will be omitted.

[0073] The slave unit control device 340A determines whether or not a request to acquire slave unit identification information has been received from the first parent unit shutoff valve device 31A (step T1). When the slave unit control device 340A receives the request to acquire slave unit identification information (step T1 / YES), it transmits the received request to acquire slave unit identification information to the subsequent first-second child unit shutoff valve device 33B (step T2). Thereafter, the slave unit control device 340A transmits the child unit identification information 343A of the first-first child unit shutoff valve device 33A to the first parent unit shutoff valve device 31A (step T3).

[0074] If the slave unit control device 340A has not received a request to obtain slave unit identification information from the first parent unit shut-off valve device 31A (step T1 / NO), it determines whether or not it has received slave unit identification information 343 from the subsequent first-second child unit shut-off valve device 33B (step T4).

[0075] When the slave unit control device 340A receives the slave unit identification information 343 from the subsequent first-second slave unit shutoff valve device 33B (step T4 / YES), it transmits the received slave unit identification information 343 to the first parent unit shutoff valve device 31A (step T3).

[0076] If the slave control device 340A has not received the slave identification information 343 from the subsequent first-second slave shut-off valve device 33B (step T4 / NO), it determines whether or not it has received an instruction to close the shut-off valve from the first parent shut-off valve device 31A (step T5).

[0077] When the slave unit control device 340A receives the instruction to close the shutoff valve from the first master unit shutoff valve device 31A (step T5 / YES), it closes the shutoff valve 333A of the 1-1 slave unit shutoff valve device 33A (step T6). In addition, the slave unit control device 340A transmits an instruction to close the shutoff valve to the subsequent 1-2 slave unit shutoff valve device 33B (step T7).

[0078] In addition, if the slave unit control device 340A has not received an instruction to close the shut-off valve from the first master unit shut-off valve device 31A (step T5 / NO), it determines whether the elapsed time since it last received a request to obtain slave unit identification information has exceeded a preset time (step T8).

[0079] If the elapsed time has not exceeded the preset time (step T8 / NO), the slave device control device 340A returns to the determination in step T1.

[0080] When the elapsed time exceeds a preset time (step T8 / YES), the slave unit control device 340A determines that communication with the first parent unit shut-off valve device 31A has become impossible, and closes the shut-off valve 333A of the 1-1 slave unit shut-off valve device 33A (step T9).

[0081] Next, the slave device control device 340A determines whether or not communication with the subsequent first-second slave device shutoff valve device 33B is possible (step T10). If communication with the subsequent first-second slave device shutoff valve device 33B is not possible (step T10 / NO), the slave device control device 340A ends this processing flow.

[0082] In addition, if the slave control device 340A is able to communicate with the downstream 1-2 slave shut-off valve device 33B (step T10 / YES), it sends an instruction to the downstream 1-2 slave shut-off valve device 33B to close the shut-off valve (step T11).

[0083] [1-3:Second action] FIG. 8 is a flowchart showing the second operation of the master unit shutoff valve device 31. The second operation of the parent unit shutoff valve device 31 will be described with reference to the flowchart shown in Fig. 8. Note that the operations of steps S21 to S24 in the flowchart shown in Fig. 8 are the same as S1 to S4 in the flowchart shown in Fig. 5, and therefore description thereof will be omitted.

[0084] If there is a slave unit shutoff valve device 33 from which the master unit control device 320A cannot acquire the slave unit identification information (step S25 / YES), it transmits a second abnormality code to the first indoor unit 51. This second abnormality code is a code indicating that a communication abnormality has occurred in some of the slave unit shutoff valve devices 33, but that the other shutoff valve devices 30 are able to communicate with the first indoor unit 51.

[0085] When the first indoor unit 51 receives the second abnormality code from the master unit shutoff valve device 31A, it transmits the second abnormality code to the first remote controller 71A while maintaining a state in which air conditioning operation is possible. When the first remote control 71 receives the second abnormality code, it displays that a communication abnormality has occurred in some of the slave unit shutoff valve devices 33, that the other shutoff valve devices 30 are able to communicate with the first indoor unit 51, and that the first indoor unit 51 is in a state where air conditioning operation is possible. Furthermore, if there is no slave unit shutoff valve device 33 from which the master unit control device 320A cannot acquire slave unit identification information (step S25 / NO), the master unit control device 320A ends this processing flow.

[0086] The second operation of the master unit shutoff valve device 31 when communication with the indoor unit 50 becomes impossible is the same as the flowchart shown in FIG. 6, and therefore a detailed description thereof will be omitted.

[0087] FIG. 9 is a flowchart showing the second operation of the first-second slave cutoff valve device 33B. Next, a description will be given of the second operation of the slave unit shutoff valve device 33. Below, the operation of the first-second slave unit shutoff valve device 33B will be described as a representative, and a description of the operation of the other slave unit shutoff valve devices 33 will be omitted. In addition, the operation of steps T21 to T24 shown in Fig. 9 is the same as steps T1 to T4 shown in Fig. 7, and therefore a description thereof will be omitted.

[0088] If the slave control device 340B has not received the slave identification information 343 from the subsequent 1st-3rd slave shut-off valve device 33C (step T24 / NO), it determines whether the elapsed time since the last time it received a request to obtain the slave identification information has exceeded a preset time (step T25).

[0089] If the elapsed time has not reached the preset time (step T25 / NO), the slave device control device 340B returns to the determination in step T21.

[0090] When the elapsed time exceeds a preset time (step T25 / YES), the slave unit control device 340A determines that communication with the 1-1 slave unit shut-off valve device 33A has become impossible, and closes the shut-off valve 333B of the 1-2 slave unit shut-off valve device 33B (step T26).

[0091] In this second operation, for example, when the first-second slave unit cutoff valve device 33B is in a state where communication is disabled, the cutoff valve 333B of the first-second slave unit cutoff valve device 33B itself is controlled to a closed state. Comparing the flowchart of the first operation shown in Fig. 7 with the flowchart of the second operation shown in Fig. 9, in the second operation, steps T5 to T7 and steps T10 and T11 shown in the flowchart of Fig. 7 are omitted. Therefore, the shutoff valve 333 of the 1-1 slave unit shutoff valve device 33A, which is located upstream of the 1-2 slave unit shutoff valve device 33B, and the shutoff valve 315A of the first master unit shutoff valve device 31A are maintained in an open state. Therefore, until maintenance is performed on the slave unit shutoff valve device 33 that is not able to communicate, refrigerant can be supplied to the indoor unit 50 to continue air conditioning operation, and a decrease in user comfort can be suppressed.

[0092] In the above-described first embodiment, the parent device storage unit 321A has been described as storing the child device identification information 323A of each child device shutoff valve device 33. Alternatively, the parent device storage unit 321A may store information on the number of child device shutoff valve devices 33 daisy-chained to the first parent device shutoff valve device 31A. In this case, the parent device control device 320A detects the number of child device shutoff valve devices 33 with which it can communicate based on the child device identification information 343 received from the child device shutoff valve devices 33. The parent device control device 320A determines whether the detected number of child device shutoff valve devices 33 with which it can communicate matches the number information stored in the parent device storage unit 321A, and can thereby determine whether communication with all child device shutoff valve devices 33 connected in the daisy chain is normal.

[0093] [1-4: Effects, etc.] As described above, in this embodiment, the air conditioning system 1 comprises an outdoor unit 10, an indoor unit 50, and a plurality of shut-off valve devices 30 arranged in parallel on a refrigerant pipe 20 connecting the outdoor unit 10 and the indoor unit 50.

[0094] According to this configuration, multiple shutoff valve devices 30 are arranged in parallel on the refrigerant pipe 20 connecting the outdoor unit 10 and the indoor unit 50. When the air conditioning capacity of the indoor unit 50 is high, the diameter of the refrigerant pipe is changed to ensure a sufficient refrigerant flow rate, and so it was previously necessary to provide a shutoff valve device 30 corresponding to the diameter of the refrigerant pipe 20. However, by arranging multiple shutoff valve devices 30 in parallel, it is no longer necessary to prepare a shutoff valve device 30 corresponding to a refrigerant pipe 20 with a large diameter, thereby improving user convenience.

[0095] The plurality of shutoff valve devices 30 include a master unit shutoff valve device 31 connected to the indoor unit 50 via a remote control line 60, and a slave unit shutoff valve device 33 connected to the master unit shutoff valve device 31 via a communication line 40. The indoor unit 50 and the parent unit shut-off valve device 31 belong to the same group that manages the communication status, the parent unit shut-off valve device 31 manages the communication status with the child unit shut-off valve device 33, and the remote control line 60 has a limit to the number of indoor units 50 and shut-off valve devices 30 that can be recognized as being in the same group.

[0096] According to this configuration, the indoor unit 50 and the parent unit shutoff valve device 31 are connected by a remote control line 60, and the parent unit shutoff valve device 31 and the child unit shutoff valve device 33 are connected by a communication line 40. If the remote control line 60 is limited in the number of indoor units 50 and shutoff valve devices 30 that can be recognized as part of the same group, by connecting only the parent unit shutoff valve device 31 to the indoor unit 50 by the remote control line 60 and connecting the parent unit shutoff valve device 31 and the child unit shutoff valve device 33 by the communication line 40, it is possible to ensure the number of indoor units 50 connected by the remote control line 60 even if the air conditioning system 1 is configured to have multiple child unit shutoff valve devices 33.

[0097] The air conditioning system 1 includes a plurality of slave shutoff valve devices 33. The master shutoff valve device 31 and the plurality of slave shutoff valve devices 33 are daisy-chain connected by a communication line 40.

[0098] According to this configuration, the parent shutoff valve device 31 and multiple child shutoff valve devices 33 are daisy-chain connected by the communication line 40. Therefore, even if the parent shutoff valve device 31 has a small number of connection terminals, multiple child shutoff valve devices 33 can be connected.

[0099] The master shutoff valve device 31 includes a master storage unit 321 that stores the number of slave shutoff valve devices 33 connected thereto.

[0100] According to this configuration, the parent unit shutoff valve device 31 includes a parent unit memory unit 321 that stores the number of multiple child unit shutoff valve devices 33. Therefore, the parent unit shutoff valve device 31 can determine whether or not a communication abnormality has occurred in the multiple child unit shutoff valve devices 33 by detecting the number of child unit shutoff valve devices 33 with which it can communicate.

[0101] The master shutoff valve device 31 includes a master storage unit 321 that stores slave identification information 323 for identifying each of the multiple slave shutoff valve devices 33 connected thereto.

[0102] According to this configuration, the master shutoff valve device 31 includes a master storage unit 321 that stores slave identification information 323 that identifies each of the multiple slave shutoff valve devices 33. Therefore, by acquiring the slave identification information 323 from each of the multiple slave shutoff valve devices 33, it is possible to determine that a communication abnormality has occurred in a slave shutoff valve device 33 from which the slave identification information could not be acquired.

[0103] When communication with the indoor unit 50 becomes impossible, the master unit shutoff valve device 31 closes to prevent the inflow of refrigerant into the indoor unit 50, and instructs the multiple slave unit shutoff valve devices 33 to close. Furthermore, when communication with the master unit shutoff valve device 31 becomes impossible, the indoor unit 50 prohibits the execution of air conditioning operation.

[0104] According to this configuration, when communication between the indoor unit 50 and the master unit shutoff valve device 31 becomes impossible, the master unit shutoff valve device 31 and the multiple slave unit shutoff valve devices 33 are closed, and air conditioning operation is prohibited in the indoor unit 50. This prevents refrigerant from flowing into the indoor unit 50, ensuring safety.

[0105] When the master unit shutoff valve device 31 detects a slave unit shutoff valve device 33 that is unable to communicate among the multiple slave unit shutoff valve devices 33, it closes to prevent the inflow of refrigerant into the indoor unit 50 and notifies the indoor unit 50 that a slave unit shutoff valve device 33 that is unable to communicate has been detected. When the multiple slave unit shutoff valve devices 33 cannot communicate with other daisy-chained slave unit shutoff valve devices 33 or the master unit shutoff valve device 31, they close to prevent the inflow of refrigerant into the indoor unit 50.

[0106] According to this configuration, when a child unit shutoff valve that cannot communicate is detected, the parent unit shutoff valve and the multiple child unit shutoff valves are closed, and the indoor unit 50 is notified that a child unit shutoff valve that cannot communicate has been detected. This prevents refrigerant from flowing into the indoor unit 50, ensuring safety.

[0107] Of the multiple slave shutoff valve devices 33, the slave shutoff valve device 33 at the previous stage in the daisy chain connection or the slave shutoff valve that can communicate with the master shutoff valve device 31 continues to be in an open state.

[0108] According to this configuration, even if a slave shut-off valve device 33 that cannot communicate is detected, the slave shut-off valve device 33 at the previous stage in the daisy chain connection or the slave shut-off valve device 33 that can communicate with the master shut-off valve device 31 will remain open, so that refrigerant can be supplied to the indoor unit 50 to continue air conditioning operation until maintenance is performed on the slave shut-off valve device 33 that cannot communicate, thereby preventing a decrease in user comfort.

[0109] [2: Embodiment 2] [2-1: Composition] FIG. 10 is a diagram showing the configuration of an air conditioning system 1 according to the second embodiment. In the refrigerant pipe 20 of the second embodiment, the gas side refrigerant pipe 110 and the liquid side refrigerant pipe 120 are not integrated, but are provided separately.

[0110] A portion of the gas side refrigerant piping 110 branches into three, a first branch gas piping 111, a second branch gas piping 113, and a third branch gas piping 115. A shutoff valve device 150 is provided in each of the three branched first branch gas piping 111, the second branch gas piping 113, and the third branch gas piping 115. A gas side parent unit shutoff valve device 151 is provided in the first branch gas piping 111, a gas side first subsidiary unit shutoff valve device 153A is provided in the second branch gas piping 113, and a gas side second subsidiary unit shutoff valve device 153B is provided in the third branch gas piping 115. The gas side parent unit shutoff valve device 151, the gas side first subsidiary unit shutoff valve device 153A, and the gas side second subsidiary unit shutoff valve device 153B are arranged in parallel. The first gas-side slave shutoff valve device 153A and the second gas-side slave shutoff valve device 153B are collectively referred to as the gas-side slave shutoff valve device 153.

[0111] A portion of the liquid side refrigerant piping 120 branches into three branches: a first branch liquid piping 121, a second branch liquid piping 123, and a third branch liquid piping 125. A shutoff valve device 150 is provided in each of the three branches: the first branch liquid piping 121, the second branch liquid piping 123, and the third branch liquid piping 125. A liquid side parent unit shutoff valve device 155 is provided in the first branch liquid piping 121, a liquid side first child unit shutoff valve device 157A is provided in the second branch liquid piping 123, and a liquid side second child unit shutoff valve device 157B is provided in the third branch liquid piping 125. The liquid side parent unit shutoff valve device 155, the liquid side first child unit shutoff valve device 157A, and the liquid side second child unit shutoff valve device 157B are arranged in parallel. The liquid-side first slave shutoff valve device 157A and the liquid-side second slave shutoff valve device 157B are collectively referred to as the liquid-side slave shutoff valve device 157.

[0112] The gas-side parent unit shutoff valve device 151 and the liquid-side parent unit shutoff valve device 155 are connected to be able to communicate with each other. Fig. 10 shows an example in which the gas-side parent unit shutoff valve device 151 and the liquid-side parent unit shutoff valve device 155 are connected by a remote control line 60, but the gas-side parent unit shutoff valve device 151 and the liquid-side parent unit shutoff valve device 155 may also be connected by a communication line 40.

[0113] [2-2: Operation] In embodiment 2, for example, when the gas side parent unit shutoff valve device 151 detects a gas side child unit shutoff valve device 153 with which communication is not possible, it notifies the liquid side parent unit shutoff valve device 155 of the number of gas side child unit shutoff valve devices 153 with which communication is possible.

[0114] When the liquid side parent unit shut-off valve device 155 receives the number of gas side child unit shut-off valve devices 153 with which it can communicate, it selects the same number of liquid side child unit shut-off valve devices 157 as the notified number and sends a shut-off valve closing instruction to the liquid side child unit shut-off valve devices 157 other than the selected liquid side child unit shut-off valve devices 157.

[0115] The liquid-side slave-unit shutoff valve device 157 selected by the liquid-side master-unit shutoff valve device 155 is maintained in an open state. Therefore, the same number of shutoff valve devices 30 are open in the gas-side refrigerant piping 110 and the liquid-side refrigerant piping 120. This reduces the difference in refrigerant flow rate between the gas-side refrigerant piping 110 and the liquid-side refrigerant piping 120, thereby suppressing pressure loss in the refrigerant flow. This prevents a significant decrease in user comfort until maintenance is performed on the non-communicable gas-side slave-unit shutoff valve device 153 or liquid-side slave-unit shutoff valve device 157.

[0116] Furthermore, when the liquid side parent unit shutoff valve device 155 detects a liquid side slave unit shutoff valve device 157 that cannot communicate, it notifies the gas side parent unit shutoff valve device 151 of the number of liquid side slave unit shutoff valve devices 157 that can communicate.

[0117] When the gas side parent unit shut-off valve device 151 receives the number of liquid side child unit shut-off valve devices 157 with which it can communicate, it selects the same number of gas side child unit shut-off valve devices 153 as the notified number and sends a shut-off valve closing instruction to the gas side child unit shut-off valve devices 153 other than the selected gas side child unit shut-off valve devices 153.

[0118] The gas side slave shutoff valve device 153 selected by the gas side parent unit shutoff valve device 151 is maintained in an open state. Therefore, the same number of shutoff valve devices 30 are open in the gas side refrigerant piping 110 and the liquid side refrigerant piping 120. This reduces the difference in refrigerant flow rate between the gas side refrigerant piping 110 and the liquid side refrigerant piping 120, thereby suppressing pressure loss in the refrigerant flow. This prevents a significant decrease in user comfort until maintenance is performed on the gas side slave shutoff valve device 153 or liquid side slave shutoff valve device 157 that cannot communicate.

[0119] [2-3: Effects] In the second embodiment, when a communication abnormality is detected in the gas side slave unit shutoff valve device 153 or the liquid side slave unit shutoff valve device 157, the same number of shutoff valve devices 30 are controlled to be in the open state in the gas side refrigerant piping 110 and the liquid side refrigerant piping 120. This reduces the difference in refrigerant flow rate between the gas side refrigerant piping 110 and the liquid side refrigerant piping 120, thereby suppressing pressure loss in the refrigerant flow. This prevents a significant decrease in user comfort until maintenance is performed on the gas side slave unit shutoff valve device 153 or liquid side slave unit shutoff valve device 157 that is unable to communicate.

[0120] [3: Embodiment 3] FIG. 11 is a diagram showing an example of the circuit board configuration of the first parent unit cutoff valve device 31A. The first parent shutoff valve device 31A includes a power terminal block 410A, a communication terminal block 420A, a communication board 430A, and a main board 450A.

[0121] The power terminal block 410A is connected to a power terminal of a power cable, and power is supplied from the power supply to the communication board 430A and the main board 450A via the power cable.

[0122] The communication terminal block 420A has a plurality of connection terminals connected to the communication line 40 and the remote control line 60. The communication terminal block 420A has a first connection terminal 421A and a second connection terminal 422A which are connection terminals with the remote control line 40, and a third connection terminal 423A and a fourth connection terminal 424A which are connection terminals with the remote control line 60.

[0123] The communication board 430A is equipped with the communication line I / F 311A and the remote control line I / F 313A shown in FIG.

[0124] The main board 450A is equipped with a master unit control device 320A. As described above, the master unit control device 320A performs mutual data communication with the indoor unit 50. Furthermore, the master unit control device 320A controls the shutoff valve 315A to an open state or a closed state in response to instructions from the indoor unit 50.

[0125] Furthermore, a switch section 460A is arranged on the main board 450A. The switch section 460A includes a dip switch section 470A and a rotary switch 480A. The dip switch section 470A includes a first dip switch 471A and a second dip switch 473A.

[0126] The first dip switch 471A is set to the second digit of the number indicating the total number of the first parent shutoff valve device 31A and the child shutoff valve devices 33 connected in a daisy chain. The rotary switch 480A has an operating shaft 485A. The user rotates the operating shaft 485A to set one of the first digit numbers 1 to 9 on the rotary switch 480A. The first digit of the number indicating the total number of the first parent shutoff valve device 31A and the daisy-chained child shutoff valve devices 33 is set on the rotary switch 480A. In the example shown in Figure 11, the rotary switch 480A is set to "1" and the first dip switch 471A is turned on, so "11" is set as the number indicating the total number of the first parent shut-off valve device 31A and the child shut-off valve devices 33 connected in a daisy chain. The master control device 320A recognizes the total number of first master shutoff valve devices 31A and daisy-chained slave shutoff valve devices 33 based on the number set in the switch section 460A.

[0127] The second dip switch 473A is a switch that forcibly puts the shutoff valve 315A provided in the first parent unit shutoff valve device 31A into an open state.

[0128] The main board 450A is also equipped with a first switch 491A and a second switch 493A that control the shutoff valve 315A provided in the master control device 320A to an open state or a closed state. The master control device 320A is equipped with, for example, two shutoff valves 315A. The first switch 491A and the second switch 493A are switches that control these two shutoff valves 315A to an open state or a closed state.

[0129] If each of the indoor units 50, the first indoor unit 51 and the second indoor unit 53, is configured to be able to switch between cooling operation and heating operation, a separate shutoff valve may be provided to switch the flow of refrigerant between cooling operation and heating operation. In this case, two more shutoff valves 315A are required, for a total of four, and two more switches are also required to control these shutoff valves 315A between an open state and a closed state.

[0130] 11 shows the configuration of the first parent unit shutoff valve device 31A, but like the first parent unit shutoff valve device 31A, the child unit shutoff valve device 33 is also configured with a switch section on a main board that includes a dip switch section and a rotary switch. A number indicating the connection order of the daisy chain connection is set in the switch section of the child unit shutoff valve device 33. For example, the 1-1 child unit shutoff valve device 33A shown in FIG. 1 is first in the connection order of the daisy chain connection, so the number "1" is set in the rotary switch, and the 1-2 child unit shutoff valve device 33B shown in FIG. 1 is second in the connection order of the daisy chain connection, so the number "2" is set in the rotary switch.

[0131] FIG. 12 is a diagram showing a configuration in which an indoor unit 50, a first parent-unit shutoff valve device 31A, and a first-1 child-unit shutoff valve device 33A are connected by a communication line 40. As shown in FIG. In the above-described first and second embodiments, the first indoor unit 51 and the first parent unit shut-off valve device 31A are connected by a remote control wire 60, and the first parent unit shut-off valve device 31A and the 1-1 child unit shut-off valve device 33A, the 1-1 child unit shut-off valve device 33A and the 1-2 child unit shut-off valve device 33B, and the 1-2 child unit shut-off valve device 33B and the 1-3 child unit shut-off valve device 33C are connected by a communication wire 40.

[0132] In the third embodiment, the indoor unit 50, first parent unit shutoff valve device 31A, and child unit shutoff valve device 33 are each connected by a communication line 40. Fig. 12 shows the connection configuration of the indoor unit 50, first parent unit shutoff valve device 31A, and 1-1 child unit shutoff valve device 33A, but the 1-2 child unit shutoff valve device 33B is also similarly connected to the 1-1 child unit shutoff valve device 33A by the communication line 40, and the 1-3 child unit shutoff valve device 33C is also similarly connected to the 1-2 child unit shutoff valve device 33B by the communication line 40.

[0133] As shown in FIG. 12, the communication line I / F 511 of the indoor unit 50 includes a first indoor communication terminal 511A, a second indoor communication terminal 511B, and a third indoor communication terminal 511C.

[0134] As shown in FIG. 12, the communication line I / F 311A of the first parent unit cutoff valve device 31A includes a first parent unit communication terminal 3111A, a second parent unit communication terminal 3112A, and a third parent unit communication terminal 3113A.

[0135] As shown in Fig. 12, the 1-1th child device shutoff valve device 33A includes a first child device communication terminal 3311A, a second child device communication terminal 3312A, and a third child device communication terminal 3313A. The 1-1st child device shutoff valve device 33A also includes a photocoupler 350A. In Fig. 12, the photocoupler 350A is represented as "PHC350A."

[0136] 12, the first indoor communication terminal 511A is connected to a cable that is connected to the outdoor unit 10. The communication line I / F 511 outputs data received by the first indoor communication terminal 511A to the indoor unit control device 520. The second indoor communication terminal 511B is connected to the indoor unit control device 520 and is also connected to the communication line 40 that is connected to the first parent unit shutoff valve device 31A. In the connection example shown in FIG. 12, the third indoor communication terminal 511C is not used.

[0137] 12 shows a configuration in which a relay board 600 is provided between the indoor unit 50 and the first parent unit shutoff valve device 31A. When the first parent unit shutoff valve device 31A is installed away from the indoor unit 50, the relay board 600 is placed midway along the communication line 40 connecting the indoor unit 50 and the first parent unit shutoff valve device 31A. The relay board 600 amplifies the signal input to the indoor unit 50 via the communication line 40, and outputs the amplified signal to the first parent unit shutoff valve device 31A.

[0138] In the connection example shown in Figure 12, the second parent unit communication terminal 3112A and the third parent unit communication terminal 3113A are used in the first parent unit shut-off valve device 31A, and the first parent unit communication terminal 3111A is not used, but the selection of the terminals to be used and the terminals not to be used is arbitrary.

[0139] The second parent unit communication terminal 3112A is connected to the communication line 40 which is connected to the relay board 600. The communication line I / F 311A of the first parent unit shutoff valve device 31A outputs a signal received via the second parent unit communication terminal 3112A to the parent unit control device 320A.

[0140] A communication line 40 connected to the subsequent 1-1 slave shutoff valve device 33A is connected to the third parent communication terminal 3113A. The third parent communication terminal 3113A is connected to the parent control device 320A and also to the communication line 40 connected to the 1-1 slave shutoff valve device 33A. The third master communication terminal 3113A outputs a signal input from the master control device 320A to the communication line 40 connected to the first-first slave cutoff valve device 33A.

[0141] In the connection example shown in Figure 12, in the 1-1 sub-unit shut-off valve device 33A, the first sub-unit communication terminal 3311A and the third sub-unit communication terminal 3313A are used, and the second sub-unit communication terminal 3312A is not used, but the selection of the terminals to be used and the terminals not to be used is arbitrary.

[0142] A communication line 40 that is connected to the first parent unit shutoff valve device 31A is connected to the first child unit communication terminal 3311A. The first child unit communication terminal 3311A outputs a signal received via the communication line 40 to the photocoupler 350A. The photocoupler 350A acquires data included in the signal input from the first child unit communication terminal 3311A, and outputs the acquired data to the child unit control device 340A. The third slave communication terminal 3313A is connected to a communication line 40 connected to the slave cutoff valve device 33 at the subsequent stage.

[0143] In this embodiment, a photocoupler 350A is provided in the 1-1 slave shutoff valve device 33A, and data contained in a signal received at a 1-1 slave communication terminal 3311A is acquired by the photocoupler 350A. Similarly, photocouplers 350B and 350C are provided in the 1-2 slave shutoff valve device 33B and the 1-3 slave shutoff valve device 33C, respectively.

[0144] For example, in a configuration in which the outdoor unit 10 transmits a signal indicating the status of the outdoor unit 10 to the indoor unit 50 at regular intervals, and the indoor unit 50 outputs the received signal to the downstream first parent unit shutoff valve device 31A each time it receives a signal from the outdoor unit 10, the photocoupler 350A in the 1-1 child unit shutoff valve device 33A operates more frequently, increasing the probability of failure of the photocoupler 350A.

[0145] For this reason, the indoor unit control device 520 is configured to determine whether or not there has been a change in the signal indicating the state of the outdoor unit 10, and to output an instruction corresponding to the received signal to the downstream first parent unit shutoff valve device 31A only if it is determined that there has been a change in the state of the outdoor unit 10. For example, assume that the signal indicating the status of the outdoor unit 10 includes 4 bits of data. Each time the indoor unit control device 520 receives data from the outdoor unit 10, it determines whether or not there is a change in the bits of this 4 bits of data. When the indoor unit control device 520 detects a change in at least one bit of the 4 bits of data, it determines that a change has occurred in the status of the outdoor unit 10, and generates a signal indicating an instruction based on the received 4 bits of data. The indoor unit control device 520 outputs the generated signal indicating the instruction to the subsequent first parent unit shutoff valve device 31A. When the first parent unit shutoff valve device 31A receives the signal indicating the instruction, it outputs the received signal indicating the instruction to the subsequent first-first child unit shutoff valve device 33A.

[0146] In this way, the indoor unit control device 520 determines whether or not there has been a change in the state of the outdoor unit 10, and outputs a signal indicating an instruction to the downstream first parent unit shutoff valve device 31A only when it determines that there has been a change in the state of the outdoor unit 10. With this configuration, it is possible to prevent failure of the photocoupler 350A.

[0147] [4: Other embodiments] As described above, the above-described embodiments have been described as examples disclosed in the present application. However, the technology in the present disclosure is not limited to these, and can be applied to embodiments in which modifications, substitutions, additions, omissions, etc. are made. Furthermore, it is also possible to combine the components described in the above-described embodiments to create new embodiments.

[0148] For example, in the above-described first and second embodiments, the parent shutoff valve device 31 identifies the child shutoff valve device 33 having a communication abnormality based on the child identification information that it was unable to receive. Alternatively, the multiple child shutoff valve devices 33 may be configured to notify the child shutoff valve device 33 connected to the preceding stage of the communication abnormality when communication with the child shutoff valve device 33 connected to the subsequent stage in the daisy chain connection becomes impossible. According to this configuration, the slave unit shutoff valve device 33 connected to the upstream side notifies the master unit shutoff valve device 31 of the occurrence of the slave unit shutoff valve device 33. Therefore, the indoor unit 50 can be notified that a slave unit shutoff valve device 33 that is unable to communicate has been detected, and the indoor unit 50 that has received the notification can prohibit air conditioning operation, ensuring safety.

[0149] In the above-described first and second embodiments, a case has been described in which a plurality of slave shutoff valve devices 33 are daisy-chain connected to the master shutoff valve device 31. Alternatively, a configuration in which a plurality of slave shutoff valve devices 33 are connected in parallel to the master shutoff valve device 31 may be used. In a configuration in which multiple slave shutoff valve devices 33 are daisy-chained to the master shutoff valve device 31, the slave shutoff valve devices 33 subsequent to the slave shutoff valve device 33 in which the communication abnormality occurred must be closed. On the other hand, in a configuration in which multiple slave shutoff valve devices 33 are connected in parallel to the master shutoff valve device 31, the slave shutoff valve devices 33 other than the slave shutoff valve device 33 in which the communication abnormality occurred can be kept open, so that the refrigerant flow rate can be secured during air conditioning operation until maintenance.

[0150] Furthermore, when the master unit shutoff valve device 31 detects a communication abnormality in the slave unit shutoff valve device 33, it may notify the first indoor unit 51 of the communication abnormality in the slave unit shutoff valve device 33 and information indicating which slave unit shutoff valve device 33 has the communication abnormality. Upon receiving the notification from the master unit shutoff valve device 31, the first indoor unit 51 may transmit the communication abnormality in the slave unit shutoff valve device 33 and information indicating which slave unit shutoff valve device 33 has the communication abnormality to the first remote control 71, and cause the display unit provided in the first remote control 71 to display this information.

[0151] In the second operation, if the ratio of the number of shut-off valve devices that can communicate with the indoor units 50 to the total number of shut-off valve devices 30 connected in a daisy chain is equal to or less than a predetermined value, such as 20%, the air conditioning operation of the indoor units 50 may be prohibited and all shut-off valve devices 30 may be closed.

[0152] If the shutoff valve device 30 has identification information, when a communication abnormality occurs in the shutoff valve device 30, the identification information of the shutoff valve device 30 in which the communication abnormality occurred may be displayed on a remote control, a separately provided management device, or the like. By displaying the identification information of the shutoff valve device 30 in which the communication abnormality occurred on the remote control or management device, it becomes easier for a worker performing maintenance work to identify the shutoff valve device 30 to check or repair from among the multiple shutoff valve devices 30 provided in the air conditioning system 1.

[0153] The first and second operations may be switchable by remote control operation, etc. For example, if the slave shutoff valve device 33 is unable to communicate but some of the shutoff valve devices 30 are able to communicate, a screen may be displayed on the remote control or management terminal to confirm whether or not to continue air conditioning operation using the shutoff valve device 30 that is able to communicate. In this case, if an operation to continue the operable state is displayed, the second operation may be performed, and if an operation to prohibit air conditioning operation is received, the first operation may be performed. In this case, if communication between the indoor unit 50 and the master shutoff valve device 31 becomes impossible, it is preferable to control to the first operation without displaying the confirmation message to the user.

[0154] In the first and second embodiments, the first alarm device 73 and the second alarm device 83 are provided with leakage sensors 75, 85, respectively. However, the installation form of the leakage sensors is not limited to this, and the indoor unit 50 may also be provided with the leakage sensors 75, 85 built in.

[0155] Furthermore, for example, the step units of the operation shown in Figures 5, 6, and 8 are divided according to the main processing content to make it easier to understand the processing of the parent unit shutoff valve device 31A, and the method of dividing the processing units or the names thereof do not limit the present invention. The processing may be divided into more step units according to the processing content. Furthermore, one step unit may be divided so as to include more processing. Furthermore, the order of the steps may be changed as appropriate within the scope of the present invention. The same applies to the child unit shutoff valve device 33 shown in Figures 7 and 9. It should be noted that the above-described embodiments are intended to illustrate the technology of the present disclosure, and various modifications, substitutions, additions, omissions, etc. may be made within the scope of the claims or their equivalents.

[0156] [5: Note] The above description of the embodiments discloses the following techniques.

[0157] (Technology 1) An air conditioning system comprising an outdoor unit, an indoor unit, a leak sensor that detects refrigerant leakage, and a plurality of shut-off valves arranged in parallel on refrigerant piping connecting the outdoor unit and the indoor unit, which close when the leak sensor detects a refrigerant leakage.

[0158] With this configuration, multiple shutoff valves are arranged in parallel on the refrigerant piping connecting the outdoor unit and the indoor unit. When the indoor unit has a high air conditioning capacity, the diameter of the refrigerant piping needs to be changed to ensure a sufficient refrigerant flow rate, and a shutoff valve corresponding to the diameter of the refrigerant piping must be provided. However, by arranging multiple shutoff valves in parallel, there is no need to prepare shutoff valves corresponding to refrigerant piping with a large diameter, improving convenience.

[0159] (Technology 2) The air conditioning system described in Technology 1, wherein the plurality of shut-off valves comprise a parent unit shut-off valve connected to the indoor unit by a remote control line, and a child unit shut-off valve connected to the parent unit shut-off valve by a communication line, the indoor unit and the parent unit shut-off valve belong to the same group that manages their communication status, the parent unit shut-off valve manages the communication status with the child unit shut-off valve, and the remote control line has a limit to the number of indoor units and shut-off valves that can be recognized as being in the same group.

[0160] With this configuration, the indoor unit and the parent unit shutoff valve are connected by a remote control wire, and the parent unit shutoff valve and the child unit shutoff valve are connected by a communication wire. If the remote control wire has a limit on the number of indoor units and shutoff valves that can be recognized as part of the same group, by connecting only the parent unit shutoff valve to the indoor unit by a remote control wire and connecting the parent unit shutoff valve and the child unit shutoff valve by a communication wire, it is possible to ensure the number of remote controls and indoor units that can be connected by remote control wire, even in a configuration where multiple child unit shutoff valves are provided in the air conditioning system.

[0161] (Technology 3) The air conditioning system according to Art 2 includes a plurality of the slave shutoff valves, and the master shutoff valve and the plurality of slave shutoff valves are daisy-chain connected by the communication line.

[0162] With this configuration, the master shutoff valve and multiple slave shutoff valves are daisy-chained together via communication lines, making it possible to connect multiple slave shutoff valves even if the master shutoff valve has a small number of connection terminals.

[0163] (Technology 4) The air conditioning system according to technique 3, wherein the parent unit shutoff valve includes a memory unit that stores the number of the plurality of child unit shutoff valves connected thereto.

[0164] According to this configuration, the master shutoff valve includes a memory unit that stores the number of slave shutoff valves. Therefore, the master shutoff valve can determine whether a communication abnormality has occurred in the slave shutoff valves by detecting the number of slave shutoff valves with which it can communicate.

[0165] (Technology 5) The air conditioning system according to technology 3, wherein the parent unit shutoff valve includes a storage unit that stores identification information that identifies each of the plurality of child unit shutoff valves connected thereto.

[0166] According to this configuration, the master shutoff valve includes a memory unit that stores identification information that identifies each of the multiple slave shutoff valves. Therefore, by acquiring the identification information from each of the multiple slave shutoff valves, it is possible to determine that a communication abnormality has occurred in a slave shutoff valve for which identification information could not be acquired.

[0167] (Technology 6) The air conditioning system of configuration 3, wherein when communication with the indoor unit becomes impossible, the parent unit shutoff valve closes to prevent refrigerant from flowing into the indoor unit and instructs the multiple child unit shutoff valves to close, and when communication with the parent unit shutoff valve becomes impossible, the indoor unit prohibits air conditioning operation.

[0168] With this configuration, if communication between the indoor units and the master unit shutoff valve becomes impossible, the master unit shutoff valve and the multiple slave unit shutoff valves are closed and the indoor units are prohibited from operating in an air-conditioning mode, thereby preventing refrigerant from flowing into the indoor units and ensuring safety.

[0169] (Technology 7) The air conditioning system of configuration 3, wherein when a slave unit shutoff valve that cannot communicate is detected among the plurality of slave unit shutoff valves, the master unit shutoff valve closes to prevent refrigerant from flowing into the indoor unit and notifies the indoor unit that the slave unit shutoff valve that cannot communicate has been detected, and when communication with other slave unit shutoff valves connected in the daisy chain or the master unit shutoff valve becomes impossible, the plurality of slave unit shutoff valves close to prevent refrigerant from flowing into the indoor unit.

[0170] With this configuration, when a disabled slave unit shutoff valve is detected, the master unit shutoff valve and multiple slave unit shutoff valves are closed, and the indoor unit is notified that a disabled slave unit shutoff valve has been detected. This prevents refrigerant from flowing into the indoor unit, ensuring safety.

[0171] (Technology 8) An air conditioning system as described in configuration 7, wherein, among the multiple slave shutoff valves, the slave shutoff valve at the previous stage of the daisy chain connection or the slave shutoff valve capable of communicating with the master shutoff valve remains in an open state.

[0172] With this configuration, even if a child unit shut-off valve that cannot communicate is detected, the child unit shut-off valve at the previous stage in the daisy chain connection, or the child unit shut-off valve that can communicate with the parent unit shut-off valve, will remain open, so that refrigerant can be supplied to the indoor unit to continue air conditioning operation until maintenance is performed on the child unit shut-off valve that cannot communicate, thereby preventing a decrease in user comfort.

[0173] (Technology 9) The refrigerant piping comprises a gas side refrigerant piping and a liquid side refrigerant piping, and a plurality of shutoff valves, the same number of which are arranged in parallel on the gas side refrigerant piping and the liquid side refrigerant piping, respectively, and the plurality of shutoff valves arranged on the gas side refrigerant piping comprise a first parent shutoff valve and a plurality of first child shutoff valves, and the plurality of shutoff valves arranged on the liquid side refrigerant piping comprise a second parent shutoff valve and a plurality of second child shutoff valves, and when a first child shutoff valve that is unable to communicate is detected, the first parent shutoff valve notifies the second parent shutoff valve of the number of first child shutoff valves that are able to communicate, An air conditioning system as described in Appendix 1, wherein the second parent unit shut-off valve selects the same number of second child unit shut-off valves as the number notified by the first parent unit shut-off valve and instructs the second child unit shut-off valves other than the selected second child unit shut-off valves to close, and when the second parent unit shut-off valve detects a second child unit shut-off valve that cannot communicate, it notifies the first parent unit shut-off valve of the number of second child unit shut-off valves that can communicate, and the first parent unit shut-off valve selects the same number of first child unit shut-off valves as the number notified by the second parent unit shut-off valve and instructs the first child unit shut-off valves other than the selected first child unit shut-off valve to close.

[0174] According to this configuration, when a first slave shut-off valve that cannot communicate is detected, the first master shut-off valve notifies the second master shut-off valve of the number of first slave shut-off valves that can communicate. The second master shut-off valve selects the same number of second slave shut-off valves as the number notified by the first master shut-off valve, and instructs the second slave shut-off valves other than the selected second slave shut-off valves to close. Furthermore, when a second master shut-off valve that cannot communicate is detected, the second master shut-off valve notifies the first master shut-off valve of the number of second slave shut-off valves that can communicate. The first master shut-off valve selects the same number of first slave shut-off valves as the number notified by the second master shut-off valve, and instructs the first slave shut-off valves other than the selected first slave shut-off valve to close. Therefore, by matching the number of shutoff valves connected to the gas side refrigerant piping with the number of shutoff valves connected to the liquid side refrigerant piping, it is possible to prevent a state in which the flow rates of the refrigerant flowing through the gas side refrigerant piping and the liquid side refrigerant piping differ significantly, thereby reducing pressure loss in the refrigerant flow. It is also possible to prevent a significant decrease in user comfort until maintenance is performed on the disabled first or second slave unit shutoff valve. [Industrial Applicability]

[0175] As described above, the air conditioning system according to the present disclosure can be used when indoor units with high air conditioning capacity are installed. [Explanation of symbols]

[0176] 1. Air conditioning system 10 Outdoor unit 20 Refrigerant piping 21 First refrigerant piping 22 Second refrigerant piping 23 Third refrigerant piping 30 Shut-off valve device 31 Main unit shutoff valve device 33 Sub-unit shut-off valve device 40 Communication lines 50 Indoor unit 51 1st indoor unit 53 2nd indoor unit 60 Remote Control Wire 110 Gas side refrigerant piping 120 Liquid refrigerant piping 150 Shut-off valve device 311 Communication line I / F 313 Remote control line I / F 315 Shut-off valve 320 Parent control device 321 Parent unit memory section 322 Control Program 323 Handset Identification Information 325 Parent Processor 331 Communication Line I / F 333 Shut-off valve 340 Child device control device 341 Sub-unit memory section 342 Control Program 343 Handset Identification Information 345 Child Processor 350A Photocoupler 350B Photocoupler 350C Photocoupler 410A power terminal block 420A Communication Terminal Block 421A 1st connection terminal 422A Second Connection Terminal 423A 3rd connection terminal 424A 4th connection terminal 430A Communication Board 450A main board 460A switch section 470A Dip Switch Section 471A 1st dip switch 473A 2nd dip switch 480A rotary switch 485A Operation axis 491A First Switch 493A Second Switch 511 Communication line I / F 511A No. 1 indoor communication terminal 511B No. 2 indoor communication terminal 511C 3rd indoor communication terminal 513 Remote control line I / F 515 Indoor heat exchanger 517 Indoor fan 520 Indoor unit control device 521 Indoor unit storage section 523 Control Program 525 Indoor unit processor 600 relay board 3111A 1st parent unit communication terminal 3112A Second parent unit communication terminal 3113A Third parent unit communication terminal 3311A 1st handset communication terminal 3312A Second handset communication terminal 3313A 3rd handset communication terminal

Claims

1. The outdoor unit and An indoor unit, a leak sensor for detecting a refrigerant leak; a plurality of shutoff valves arranged in parallel in a refrigerant pipe connecting the outdoor unit and the indoor unit, the shutoff valves closing when the leakage sensor detects a refrigerant leak; An air conditioning system comprising:

2. The plurality of shut-off valves include: a main unit shutoff valve connected to the indoor unit by a remote control line; a slave shutoff valve connected to the master shutoff valve by a communication line; Equipped with The indoor unit and the parent unit shutoff valve belong to the same group that manages the communication state, the parent shutoff valve manages a communication state with the child shutoff valve; The air conditioning system according to claim 1 , wherein the remote control line has a limit on the number of the indoor units and the shutoff valves that can be recognized as belonging to the same group.

3. A plurality of the slave unit shutoff valves are provided, The air conditioning system according to claim 2 , wherein the master shutoff valve and the plurality of slave shutoff valves are daisy-chain connected by the communication line.

4. The air conditioning system according to claim 3 , wherein the master unit shutoff valve includes a storage unit that stores the number of the slave unit shutoff valves connected thereto.

5. The air conditioning system according to claim 3 , wherein the master unit shutoff valve includes a storage unit that stores identification information that identifies each of the plurality of slave unit shutoff valves connected thereto.

6. When communication with the indoor unit becomes impossible, the parent unit shutoff valve closes to prevent refrigerant from flowing into the indoor unit and instructs the multiple child unit shutoff valves to close; The air conditioning system according to claim 3 , wherein the indoor unit prohibits execution of air conditioning operation when communication with the parent unit shutoff valve becomes impossible.

7. The parent unit shutoff valve is When a child unit shutoff valve that cannot communicate is detected among the plurality of child unit shutoff valves, the child unit shutoff valve closes to prevent the inflow of refrigerant into the indoor unit, and notifies the indoor unit that the child unit shutoff valve that cannot communicate has been detected; The plurality of slave unit shutoff valves are The air conditioning system of claim 3, wherein when communication with other child unit shutoff valves connected in the daisy chain or the parent unit shutoff valve becomes impossible, the child unit shutoff valve closes to prevent refrigerant from flowing into the indoor unit.

8. The air conditioning system of claim 7, wherein among the plurality of slave shutoff valves, a slave shutoff valve at the previous stage of the daisy chain connection or a slave shutoff valve capable of communicating with the master shutoff valve remains open.

9. The refrigerant piping includes a gas side refrigerant piping and a liquid side refrigerant piping, A plurality of shutoff valves, the same number of which are arranged in parallel on the gas side refrigerant pipe and the liquid side refrigerant pipe, respectively; the plurality of shutoff valves arranged in the gas side refrigerant piping include a first parent unit shutoff valve and a plurality of first child unit shutoff valves, the plurality of shutoff valves arranged in the liquid side refrigerant piping include a second parent unit shutoff valve and a plurality of second child unit shutoff valves, When a first slave shutoff valve that is unable to communicate is detected, the first master shutoff valve notifies the second master shutoff valve of the number of first slave shutoff valves that are able to communicate, the second parent unit shutoff valve selects the same number of second child unit shutoff valves as the number notified by the first parent unit shutoff valve, and instructs the second child unit shutoff valves other than the selected second child unit shutoff valves to close; When a second slave shutoff valve that is unable to communicate is detected, the second master shutoff valve notifies the first master shutoff valve of the number of second slave shutoff valves that are able to communicate, The air conditioning system of claim 1, wherein the first parent unit shut-off valve selects the same number of first child unit shut-off valves as the number notified by the second parent unit shut-off valve, and instructs the first child unit shut-off valves other than the selected first child unit shut-off valves to close.

Images