Air conditioning system and control method for air conditioning system

Abstract

This disclosure provides an air conditioning system that reduces the burden on workers during inspection work of safety devices. [Solution] An air conditioning system having a plurality of indoor units connected to each other in a communicative manner and configured as a group, comprising a safety device and a terminal device, wherein when a refrigerant sensor is located inside each of the plurality of indoor units, the indoor unit configured as the master unit comprises a transmitting unit that transmits an inspection signal to all other indoor units and the refrigerant sensor when inspecting the safety device, a receiving unit that receives a response signal from all other indoor units and the refrigerant sensor, and an indicator unit that, when the receiving unit receives the response signal from all other indoor units and the refrigerant sensor, causes the display mechanism of the terminal device to display that the plurality of indoor units are in an inspection state, wherein the response signal indicates that the refrigerant sensor has been set to a pseudo-leakage state when the inspection signal is received.

Description

Technical Field

[0001] The present disclosure relates to an air conditioner and a control method for an air conditioner.

Background Art

[0002] Patent Document 1 discloses a configuration for inspecting the operation of a refrigerant leakage notification device, which is an example of a safety device, in an air conditioner that uses a flammable refrigerant.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The present disclosure provides an air conditioner and a control method for an air conditioner that can reduce the workload of an operator in the inspection work of a safety device.

Means for Solving the Problems

[0005] The air conditioning system in this disclosure is an air conditioning system having a plurality of indoor units that are connected to each other in a communicative manner and configured as a group, comprising: a safety device that performs safety measures when a refrigerant sensor detects a refrigerant leak; and a terminal device having an operating mechanism and a display mechanism, wherein when the refrigerant sensor is located inside each of the plurality of indoor units, the indoor unit configured as the master unit among the plurality of indoor units, when inspecting the safety device, comprises: a transmitting unit that transmits an inspection signal to all other indoor units and the refrigerant sensor among the plurality of indoor units indicating that an inspection has been started; a receiving unit that receives a response signal from all other indoor units and the refrigerant sensor indicating that the inspection signal has been received; and an instruction unit that, when the receiving unit receives the response signal from all other indoor units and the refrigerant sensor, causes the display mechanism of the terminal device to display that the plurality of indoor units are in an inspection state, wherein the response signal indicates that the refrigerant sensor was set to a pseudo-leakage state when the inspection signal was received.

[0006] The air conditioning system in this disclosure is an air conditioning system having a plurality of indoor units that are connected to each other in a communicative manner and configured as a group, comprising: a safety device that performs safety measures when a refrigerant sensor detects a refrigerant leak; and a terminal device having an operating mechanism and a display mechanism, wherein when the refrigerant sensor is located outside the plurality of indoor units, the indoor unit configured as the master unit among the plurality of indoor units comprises: a transmitting unit that transmits an inspection signal to the refrigerant sensor to start an inspection when inspecting the safety device; a receiving unit that receives a response signal from the refrigerant sensor indicating that the inspection signal has been received; and an instruction unit that, when the receiving unit receives the response signal from the refrigerant sensor, causes the display mechanism of the terminal device to display that the plurality of indoor units are in an inspection state, wherein the response signal indicates that the refrigerant sensor was set to a pseudo-leakage state when the inspection signal was received.

[0007] The control method for an air conditioning system in this disclosure comprises a plurality of indoor units connected to each other in a communicative manner and configured as a group, a safety device that performs safety measures when a refrigerant sensor detects a refrigerant leak, and a terminal device having an operating mechanism and a display mechanism, wherein when the refrigerant sensor is located inside each of the plurality of indoor units, the indoor unit configured as the master unit among the plurality of indoor units performs the following steps when inspecting the safety device: a transmission step of transmitting an inspection signal to all other indoor units among the plurality of indoor units and the refrigerant sensor indicating that an inspection has been started; a reception step of receiving a response signal from all other indoor units and the refrigerant sensor indicating that the inspection signal has been received; and an instruction step of, in the reception step, when the response signal has been received from all other indoor units and the refrigerant sensor, causing the display mechanism of the terminal device to display that the plurality of indoor units are in an inspection state, wherein the response signal indicates that the refrigerant sensor was set to a pseudo-leakage state when the inspection signal was received.

[0008] The control method for an air conditioning system in this disclosure comprises a plurality of indoor units connected to each other in a communicative manner and configured as a group, a safety device that performs safety measures when a refrigerant sensor detects a refrigerant leak, and a terminal device having an operating mechanism and a display mechanism, wherein when the refrigerant sensor is located outside the plurality of indoor units, the indoor unit configured as the master unit among the plurality of indoor units performs a transmission step of transmitting an inspection signal to the refrigerant sensor to start an inspection when inspecting the safety device, a reception step of receiving a response signal from the refrigerant sensor indicating that the inspection signal has been received, and an instruction step of, in the reception step, when the response signal is received from the refrigerant sensor, causing the display mechanism of the terminal device to display that the plurality of indoor units are in an inspection state, wherein the response signal indicates that the refrigerant sensor was set to a pseudo-leakage state when the inspection signal was received. [Effects of the Invention]

[0009] The air conditioning system and control method for the air conditioning system described herein can reduce the workload on workers during safety device inspection work. [Brief explanation of the drawing]

[0010] [Figure 1] Diagram showing the overall configuration of the air conditioning system in Embodiment 1. [Figure 2] This figure shows the configuration of the control unit for multiple indoor units in Embodiment 1. [Figure 3] Flowchart showing the process for inspecting the safety device in Embodiment 1 [Figure 4] Diagram showing the overall configuration of the air conditioning system in Embodiment 2. [Figure 5] This figure shows the configuration of the control unit for multiple indoor units in Embodiment 2. [Figure 6] Flowchart showing the process for inspecting the safety device in Embodiment 2 [Modes for carrying out the invention]

[0011] (Knowledge and other information that formed the basis of this disclosure)

[0012] At the time the present inventors conceived of this disclosure, a configuration for checking the operation of a refrigerant leak alarm device, which is an example of a safety device, was known in Patent Document 1, etc., for an air conditioning system using a flammable refrigerant. The above-mentioned air conditioning system had the problem of requiring workers to inspect the safety devices for each indoor unit, which placed a heavy burden on the workers.

[0013] Therefore, this disclosure provides an air conditioning system and a control method for the air conditioning system that can reduce the burden on workers during safety device inspection work.

[0014] Hereinafter, embodiments will be described in detail with reference to the drawings. However, a more detailed description than necessary may be omitted. For example, detailed descriptions of well-known matters or duplicate descriptions of substantially the same configuration may be omitted. This is to avoid making the following description overly redundant and to facilitate understanding by those skilled in the art. Note that the accompanying drawings and the following description are provided for those skilled in the art to fully understand the present disclosure, and are not intended to limit the subject matter described in the claims.

[0015] Hereinafter, the air conditioner 1 according to the present embodiment will be described with reference to FIGS. 1 to 6. The air conditioner 1 according to the present embodiment includes the air conditioner 1A according to Embodiment 1 and the air conditioner 1B according to Embodiment 2. The air conditioner 1A according to Embodiment 1 will be described with reference to FIGS. 1 to 3. The air conditioner 1B according to Embodiment 2 will be described with reference to FIGS. 4 to 6.

[0016] (Embodiment 1) [1-1. Configuration] [1-1-1. Configuration of the air conditioner] First, referring to FIG. 1, the overall configuration of the air conditioner 1A in Embodiment 1 will be described. FIG. 1 is a diagram showing the overall configuration of the air conditioner 1A in the present embodiment. As shown in FIG. 1, the air conditioner 1A includes one outdoor unit 10 and three indoor units 50 (indoor unit 50A, indoor unit 50B, and indoor unit 50C) connected in parallel to the outdoor unit 10 by refrigerant pipes 2.

[0017] In the air conditioner 1A, the outdoor unit 10, the indoor unit 50, and the refrigerant pipes 2 constitute a refrigeration cycle 5. The air conditioner 1A circulates the refrigerant compressed by the outdoor unit 10 between the outdoor unit 10 and the indoor unit 50 via the refrigerant pipes 2 to perform air conditioning in the room where the indoor unit 50 is installed. In this embodiment, a case where the air conditioner 1A uses a flammable refrigerant as the refrigerant is exemplified. The flammable refrigerant is, for example, R32. Note that the refrigerant may be a mixed refrigerant containing 70% by weight or more of R32, propane, or a mixed refrigerant containing propane. Further, the refrigerant is not limited to a flammable refrigerant and may be a non-flammable refrigerant. For example, when the air conditioner 1A uses a flammable refrigerant as the refrigerant, it is necessary to install a safety device 6 that functions as a refrigerant leakage countermeasure. The safety device 6 will be further described with reference to FIG. 2.

[0018] The outdoor unit 10 includes a compressor 11, a gas-liquid separator 12, an oil separator 13, a four-way valve 14, an outdoor heat exchanger 16 having an outdoor fan 15, and an outdoor expansion valve 一十七. A gas-liquid separator 12 for supplying gas refrigerant to the compressor 11 is connected to the suction side of the compressor 11, and a four-way valve 14 is connected to the discharge side of the compressor 11 via an oil separator 13. The outdoor heat exchanger 16 is connected to the four-way valve 14. In the outdoor heat exchanger 16, heat exchange is performed between the air sent by the outdoor fan 15 and the refrigerant flowing through the outdoor heat exchanger 16. An outdoor expansion valve 17 is connected to the downstream side of the outdoor heat exchanger 16.

[0019] The outdoor unit 10 includes an outdoor unit control unit twenty for controlling the operation of the outdoor unit 10. The outdoor unit control unit 20 controls the operations of the compressor 11, the four-way valve 14, the outdoor fan 15, the outdoor expansion valve 17, etc.

[0020] The outdoor unit control unit 20 is connected to an indoor unit control unit 60 provided in each indoor unit 50 and controlling the operation of the indoor unit 50 via a communication line 3. The outdoor unit control unit 20 communicates with the indoor unit control unit 60 via the communication line 3. A plurality of indoor units 50 are connected to the outdoor expansion valve 17 and the four-way valve 14 via a refrigerant pipe 2.

[0021] Each of the multiple indoor units 50 is equipped with an indoor heat exchanger 52, an indoor expansion valve 53, a temperature sensor 54, a humidity sensor 55, and a refrigerant sensor 56. Each of the multiple indoor units 50 is also configured to communicate with an alarm 57. The indoor heat exchanger 52 is equipped with an indoor fan 51. The temperature sensor 54 detects the temperature of the room in which the indoor unit 50 is installed. The humidity sensor 55 detects the humidity of the room in which the indoor unit 50 is installed. The refrigerant sensor 56 detects refrigerant leakage.

[0022] The alarm 57 is, for example, placed on the wall of the room where the indoor unit 50 is installed. Alternatively, the alarm 57 may be placed on the remote control 90. The alarm 57 outputs an alarm when the refrigerant sensor 56 detects a refrigerant leak, in accordance with instructions from the indoor unit control unit 60. The refrigerant sensor 56 constitutes part of the "safety device". Alarm device 57 constitutes part of the "safety device".

[0023] Embodiments 1 and 2 describe a case where the alarm 57 is placed, for example, on the wall of the room where the indoor unit 50 is installed, but the embodiments are not limited to this. The alarm 57 may also be placed, for example, inside the indoor unit 50.

[0024] The alarm device 57 includes, for example, a buzzer and multiple LEDs (Light Emitting Diodes). Furthermore, each of the multiple indoor units 50 is connected to a remote control 90 that provides instructions for starting and stopping air conditioning operation, setting the air conditioning temperature, and displaying the operating status.

[0025] The remote control 90 has an operating mechanism and a display mechanism. The operating mechanism is equipped with various keys and accepts instructions from the user. The display mechanism is equipped with a display such as an LCD (Liquid Crystal Display) and displays various images on the display.

[0026] The indoor expansion valve 53 is installed in the liquid-side piping upstream of the indoor heat exchanger 52. The indoor heat exchanger 52 is provided with a first shut-off valve 80 and a second shut-off valve 81 at both ends, which switch between a state in which the refrigerant flows and a state in which the flow of the refrigerant is blocked.

[0027] The indoor unit control unit 60 controls the operation of the first shut-off valve 80, the second shut-off valve 81, the indoor fan 51, etc. Detection signals from the temperature sensor 54, the humidity sensor 55, and the refrigerant sensor 56 are input to the indoor unit control unit 60. Based on the detection signals from the temperature sensor 54, the humidity sensor 55, and the refrigerant sensor 56, the indoor unit control unit 60 detects the temperature, humidity, and presence or absence of refrigerant leakage in the room where the indoor unit 50 is installed. The first shut-off valve 80 and the second shut-off valve 81 correspond to examples of "shut-off valves". In the following explanation, the first shut-off valve 80 and the second shut-off valve 81 may be referred to as shut-off valve 8. The shut-off valve 8 constitutes part of the "safety device".

[0028] In the air conditioning system 1A of Embodiment 1 shown in Figure 1, the three indoor units 50 (i.e., indoor unit 50A, indoor unit 50B, and indoor unit 50C) are set to the first group GR1. Furthermore, in the air conditioning system 1A of Embodiment 1 shown in Figure 1, a plurality of indoor units 50 constituting a second group (not shown) may be arranged.

[0029] Each of the multiple indoor units 50 constituting the second group is connected in parallel to the outdoor unit 10 by refrigerant piping 2, similar to the indoor units 50 constituting the first group GR1. Furthermore, each of the multiple indoor units 50 constituting the second group, together with the outdoor unit 10 and the refrigerant piping 2, constitutes a refrigeration cycle 5. In other words, the air conditioning system 1A circulates the refrigerant compressed by the outdoor unit 10 between the outdoor unit 10 and the indoor units 50 via the refrigerant piping 2, thereby providing air conditioning for the room in which the indoor units 50 are installed.

[0030] The three indoor units 50 (indoor unit 50A, indoor unit 50B, and indoor unit 50C) that make up the first group GR1 harmonize the air in a single target space enclosed by a wall WS, etc., in this case, a single room R1, as shown by the dashed line. Furthermore, of the three indoor units 50 (indoor unit 50A, indoor unit 50B, and indoor unit 50C) that make up the first group GR1, one indoor unit 50 is set as the master unit, and the other two indoor units 50 are set as slave units. Embodiment 1 describes a case where, for example, indoor unit 50A is set as the master unit, and indoor units 50B and 50C are set as slave units.

[0031] [1-1-2. Control System Configuration] Next, the configuration of the control system of the air conditioning system 1A will be described with reference to Figure 2. Figure 2 is a diagram showing the configuration of the indoor unit control unit 60 of multiple indoor units 50 in Embodiment 1. Figure 2 shows, for the sake of explanation, indoor unit 50A configured as the master unit, and indoor units 50B and 50C configured as slave units. The configurations of indoor units 50B and 50C are identical.

[0032] As shown in Figure 2, each of the indoor units 50A, 50B, and 50C is equipped with an indoor unit control unit 60 that controls the operation of the indoor unit 50. Specifically, indoor unit 50A is equipped with an indoor unit control unit 60A that controls the operation of indoor unit 50A. Indoor unit 50B is equipped with an indoor unit control unit 60B that controls the operation of indoor unit 50B. Indoor unit 50C is equipped with an indoor unit control unit 60C that controls the operation of indoor unit 50C. Since the configurations of indoor unit control unit 60B and indoor unit control unit 60C are identical, the following explanation will focus on the configuration of indoor unit control unit 60B, and the explanation of the configuration of indoor unit control unit 60C will be omitted.

[0033] The indoor unit control unit 60A includes an indoor unit communication circuit 61A, an indoor unit processor 70A, and an indoor unit memory 75A. The indoor unit control unit 60B includes an indoor unit communication circuit 61B, an indoor unit processor 70B, and an indoor unit memory 75B.

[0034] The indoor unit communication circuit 61A is connected to the respective indoor unit communication circuits 61B of indoor units 50B and 50C via communication lines 3. The indoor unit communication circuit 61A communicates with the respective indoor unit communication circuits 61B of indoor units 50B and 50C according to instructions from the indoor unit processor 70A. The indoor unit communication circuit 61A transmits, for example, an inspection signal SGM to the indoor unit 50B and the indoor unit communication circuit 61B located on the indoor unit 50B. The indoor unit communication circuit 61A also receives, for example, a response signal SGR from the indoor unit 50B and the indoor unit communication circuit 61B located on the indoor unit 50B.

[0035] Indoor unit processor 70A and indoor unit processor 70B are processors such as CPUs (Central Processing Units) and MPUs (Micro Processing Units). Indoor unit memory 75A and indoor unit memory 75B are memories that store programs and data, respectively. Indoor unit memory 75A stores indoor unit program 76A. Indoor unit memory 75B stores indoor unit program 76B.

[0036] Each of the indoor unit memory 75A and indoor unit memory 75B has a non-volatile storage area. In addition, indoor unit memory 75A may have a volatile storage area and constitute the work area of ​​indoor unit processor 70A. Similarly, indoor unit memory 75B may have a volatile storage area and constitute the work area of ​​indoor unit processor 70B. Each of the indoor unit memory 75A and indoor unit memory 75B is configured, for example, by ROM (Read Only Memory) or RAM (Random Access Memory).

[0037] The safety device 6 takes action when the refrigerant sensor 56 detects a refrigerant leak. The safety device 6 includes, for example, shut-off valves 8 (i.e., a first shut-off valve 80 and a second shut-off valve 81), a refrigerant sensor 56, and an alarm 57.

[0038] The safety device 6, which corresponds to the indoor unit 50A set as the master unit, executes safety measures when the refrigerant sensor 56A detects a refrigerant leak. The safety device 6, which corresponds to the indoor unit 50A set as the master unit, includes a shut-off valve 8A, a refrigerant sensor 56A, and an alarm 57A. The safety device 6, which corresponds to the indoor unit 50B configured as a slave unit, executes safety measures when the refrigerant sensor 56B detects a refrigerant leak. The safety device 6, which corresponds to the indoor unit 50B configured as a slave unit, includes a shut-off valve 8B, a refrigerant sensor 56B, and an alarm 57B. The safety device 6, which corresponds to the indoor unit 50C configured as a slave unit, executes safety measures when the refrigerant sensor 56C detects a refrigerant leak. The safety device 6, which corresponds to the indoor unit 50C configured as a slave unit, includes a shut-off valve 8C, a refrigerant sensor 56C, and an alarm 57C.

[0039] Each of the indoor units 50A, 50B, and 50C is equipped with a switching circuit 561 that switches between the enabled and disabled states of the refrigerant sensor 56. The switching circuit 561 is composed of various types of switches that can be operated by, for example, the operator W. By operating the switches, the operator W switches the refrigerant sensor 56 between the enabled and disabled states. Indoor unit 50A is equipped with a switching circuit 561A for switching between the enabled and disabled states of the refrigerant sensor 56A. Indoor unit 50B is equipped with a switching circuit 561B for switching between the enabled and disabled states of the refrigerant sensor 56B. Indoor unit 50C is equipped with a switching circuit 561C for switching between the enabled and disabled states of the refrigerant sensor 56C.

[0040] When the safety device 6 is inspected, the refrigerant sensor 56 is set to a simulated leak state. A "simulated leak state" indicates a state in which a refrigerant leak is simulated. When the refrigerant sensor 56 is set to a simulated leak state, it outputs a simulated leak signal SGP to the indoor unit control unit 60. When the refrigerant sensors 56 located in each of the indoor units 50A, 50B, and 50C are set to a simulated leakage state, the safety device 6 enters inspection mode. The pseudo-leakage signal SGP corresponds to an example of the response signal SGR.

[0041] When the safety device 6 is in the inspection state, the shut-off valve 8 closes in accordance with instructions from the indoor unit control unit 60. When the shut-off valve 8 closes, it transmits a normal signal SGN to the indoor unit control unit 60 indicating that it is functioning normally. If the shut-off valve 8 does not close, it transmits an abnormal signal SGA to the indoor unit control unit 60 indicating that it is malfunctioning.

[0042] In Embodiments 1 and 2, the description focuses on the case where the shut-off valve 8 closes in accordance with instructions from the indoor unit control unit 60 when the safety device 6 is in inspection mode, but the embodiments are not limited to this. When the safety device 6 is in inspection mode, the shut-off valve 8 may, for example, receive a closing instruction signal from the indoor unit control unit 60 and, upon receiving the closing instruction signal, transmit a response signal to the indoor unit control unit 60.

[0043] When the safety device 6 is in the inspection state, the alarm 57 outputs a refrigerant leak alarm according to instructions from the indoor unit control unit 60. The refrigerant leak alarm is, for example, the output of a buzzer sound and the illumination of a predetermined LCD. When the alarm 57 outputs a refrigerant leak alarm, the alarm 57 sends a normal signal SGN to the indoor unit control unit 60 indicating that it is functioning normally. When the alarm 57 does not output a refrigerant leak alarm, the alarm 57 sends an abnormal signal SGA to the indoor unit control unit 60 indicating that it is malfunctioning.

[0044] Each of the shut-off valve 8, refrigerant sensor 56, and alarm device 57 is pre-assigned a unique address. The pseudo-leakage signal SGP includes the address corresponding to the refrigerant sensor 56. Each of the normal signal SGN and abnormal signal SGA output by the shut-off valve 8 includes the address corresponding to the shut-off valve 8. Each of the normal signal SGN and abnormal signal SGA output by the alarm device 57 includes the address corresponding to the alarm device 57.

[0045] Next, we will explain the functional configuration of the indoor unit 50A, which is set as the master unit. The indoor unit processor 70 functions as a first transmission unit 71A, a first reception unit 72A, an instruction unit 73A, and a first execution unit 74A by reading and executing the indoor unit program 76A.

[0046] When inspecting the safety device 6, the first transmitting unit 71A transmits an inspection signal SGM to indoor unit 50B, indoor unit 50C, and refrigerant sensor 56A, among the three indoor units 50A, 50B, and 50C, to indicate that the inspection has begun. The refrigerant sensor 56A is a refrigerant sensor located inside the indoor unit 50A, which is set as the master unit. The first transmitting unit 71A corresponds to an example of a "transmitting unit". Refrigerant sensor 56A corresponds to an example of a "master refrigerant sensor". Indoor units 50B and 50C correspond to examples of "all other indoor units".

[0047] When the first transmitting unit 71A receives an inspection start signal SGS from the remote control 90A indicating that it will start inspecting the safety device 6, it transmits an inspection signal SGM to the indoor units 50B and 50C and the refrigerant sensor 56A indicating that it will start inspecting. The remote control 90A receives an inspection start operation QPS, which is an operation to start the inspection of the safety device 6. The inspection start operation QPS is, for example, the operation of the inspection start button located on the remote control 90A. When the remote control 90A receives the inspection start operation QPS, it transmits an inspection start signal SGS to the indoor unit control unit 60A.

[0048] The first transmitting unit 71A causes the indoor unit communication circuit 61A located in the indoor unit 50A to transmit an inspection signal SGM to the indoor unit communication circuits 61B located in the indoor units 50B and 50C, respectively.

[0049] The first receiving unit 72A receives a response signal SGR from the indoor unit 50B, indoor unit 50C, and refrigerant sensor 56A, indicating that it has received the inspection signal SGM. The first transmitting unit 71A causes the indoor unit communication circuit 61A located in the indoor unit 50A to receive the response signal SGR transmitted from the indoor unit communication circuits 61B located in the indoor units 50B and 50C, respectively. The first receiving unit 72A corresponds to an example of a "receiving unit".

[0050] If, between the time the remote control 90A receives the inspection start operation QPS and the time the first receiving unit 72A receives the response signal SGR from the indoor unit 50B, indoor unit 50C, and refrigerant sensor 56A, an inspection end operation QPE is performed on the remote control 90A, the indoor unit control unit 60A will not accept the inspection end operation QPE.

[0051] The first receiving unit 72A receives an inspection completion signal SGE from the safety device 6 corresponding to the indoor units 50B, 50C, and 50A, indicating that the inspection has been completed. The first receiving unit 72A causes the indoor unit communication circuit 61A located in the indoor unit 50A to transmit the inspection completion signal SGE transmitted from the indoor unit communication circuits 61B located in the indoor units 50B and 50C, respectively.

[0052] When the first receiving unit 72A receives a response signal SGR indicating that it has received an inspection signal SGM from indoor units 50B, 50C, and refrigerant sensor 56A, the instruction unit 73A causes the display mechanism of the remote control 90A to display that the safety devices 6 corresponding to each of the three indoor units 50A, 50B, and 50C are in an inspection state.

[0053] The remote control 90A, in accordance with instructions from the instruction unit 73A, displays on its display mechanism that the safety devices 6 corresponding to each of the three indoor units 50A, 50B, and 50C are in an inspection state. The remote control 90A displays the words "Safety device inspection in progress" on a display such as an LCD. Remote control 90A corresponds to an example of a "terminal device".

[0054] If the first receiving unit 72A does not receive a response signal SGR from at least one of the indoor units 50B, indoor units 50C, and refrigerant sensor 56A between the time the first transmitting unit 71A transmits an inspection signal SGM to the indoor units 50B, indoor units 50C, and refrigerant sensor 56A and the time a predetermined period PD has elapsed, the instruction unit 73A will cause error information to be displayed on the display mechanism of the remote control 90A. The "error information" indicates, for example, that at least one of the refrigerant sensors 56B and 56A located in each of the indoor units 50B and indoor units 50C is malfunctioning. The predetermined period of PD is, for example, 3 minutes.

[0055] The remote control 90A, in accordance with instructions from the instruction unit 73A, displays on its display mechanism that at least one of the refrigerant sensors 56B located in the indoor unit 50B, 56C located in the indoor unit 50C, and 56A is malfunctioning. For example, if the remote control 90A does not receive a response signal SGR from the indoor unit 50B, it displays the message, "The refrigerant sensor 56B of the indoor unit 50B is malfunctioning," on a display such as an LCD.

[0056] When the first receiving unit 72A receives a response signal SGR indicating that it has received an inspection signal SGM from the indoor units 50B and 50C, the instruction unit 73A drives the equipment constituting the safety device 6 corresponding to the indoor units 50B and 50C.

[0057] The instruction unit 73A transmits an instruction signal SGC to the indoor unit 50B, for example, to instruct it to drive the equipment constituting the safety device 6 corresponding to the indoor unit 50B. The instruction unit 73A also transmits an instruction signal SGC to the indoor unit 50C, for example, to instruct it to drive the equipment constituting the safety device 6 corresponding to the indoor unit 50C. The components of the safety device 6 corresponding to indoor unit 50B are, for example, a shut-off valve 8B and an alarm 57B. The components of the safety device 6 corresponding to indoor unit 50C are, for example, a shut-off valve 8C and an alarm 57C.

[0058] In Embodiments 1 and 2, the case in which the alarm 57B is located in the air conditioning system 1 is described, but the embodiments are not limited to this. The alarm 57B may be located in equipment other than the air conditioning system 1, for example, in a ventilation system. In this case, the instruction unit 73A transmits an instruction signal SGC to the ventilation system, for example, instructing it to drive the alarm 57B. The ventilation system transmits the instruction signal SGC to the alarm 57B and, upon receiving a response signal from the alarm 57B, transmits the response signal to the indoor unit control unit 60A.

[0059] When the first receiving unit 72A receives an inspection completion signal SGE from the safety devices 6 corresponding to indoor units 50B, 50C, and 50A, the instruction unit 73A causes the display mechanism of the remote control 90A to display that the inspection of the safety devices 6 corresponding to each of the three indoor units 50A, 50B, and 50C has been completed.

[0060] The remote control 90A, in accordance with instructions from the instruction unit 73A, displays on its display mechanism that the inspection of the safety devices 6 corresponding to each of the three indoor units 50A, 50B, and 50C has been completed. The remote control 90A displays the words "Safety device inspection completed" on a display such as an LCD.

[0061] When the first receiving unit 72A receives an abnormal signal SGA from at least one of the safety devices 6 corresponding to indoor units 50B, 50C, and 50A, the instruction unit 73A causes the display mechanism of the remote control 90A to display that an abnormality has occurred.

[0062] The remote control 90A, following instructions from the instruction unit 73A, displays on its display mechanism that an abnormality has occurred in the device corresponding to the address included in the abnormality signal SGA. For example, the remote control 90A displays the message, "An abnormality has occurred in the alarm 57B of the indoor unit 50B," on a display such as an LCD.

[0063] When the first transmission unit 71A transmits the inspection signal SGM, if the refrigerant sensor 56A is present and the refrigerant sensor 56A is in an active state, the first execution unit 74A transmits information to the first receiving unit 72A indicating that it has received a response signal SGR from the refrigerant sensor 56A. When the first transmission unit 71A transmits an inspection signal SGM, if the refrigerant sensor 56A is not installed or the refrigerant sensor 56A is in an inactive state, the first execution unit 74A transmits information to the first receiving unit 72A indicating that it has not received a response signal SGR from the refrigerant sensor 56A.

[0064] When the first receiver 72A receives a response signal SGR indicating that it has received an inspection signal SGM from the indoor unit 50B, the indoor unit 50C, and the refrigerant sensor 56A, the first execution unit 74A drives the equipment constituting the safety device 6 corresponding to the indoor unit 50A. The components of the safety device 6 include, for example, a shut-off valve 8A and an alarm 57A. The first execution unit 74A, for example, closes the shut-off valve 8A. The first execution unit 74A also, for example, causes the alarm device 57A to output a refrigerant leak alarm.

[0065] When the first execution unit 74A receives a normal signal SGN from the shut-off valve 8A and the alarm 57A, it notifies the first receiving unit 72A that the inspection of the safety device 6 corresponding to the indoor unit 50A has been completed. For example, when the first execution unit 74A receives a normal signal SGN from the shut-off valve 8A and the alarm 57A, it notifies the first receiving unit 72A that it has received an inspection completion signal SGE from the safety device 6 corresponding to the indoor unit 50A.

[0066] Next, we will explain the functional configuration of indoor units 50B and 50C, which are configured as slave units. For convenience, in the following explanation, we will describe indoor unit 50B, and omit the explanation of indoor unit 50C. The indoor unit processor 70 functions as a second receiving unit 71B, a second transmitting unit 72B, and a second execution unit 73B by reading and executing the indoor unit program 76B.

[0067] The second receiving unit 71B receives the inspection signal SGM transmitted from the indoor unit 50A. The second receiving unit 71B causes the indoor unit communication circuit 61B to receive the inspection signal SGM transmitted from the indoor unit communication circuit 61A located on the indoor unit 50A.

[0068] The second receiving unit 71B receives the instruction signal SGC transmitted from the indoor unit 50A. The second receiving unit 71B causes the indoor unit communication circuit 61B to receive the instruction signal SGC transmitted from the indoor unit communication circuit 61A located in the indoor unit 50A.

[0069] When the second receiving unit 71B receives the inspection signal SGM from the indoor unit 50A, it forwards the inspection signal SGM to the refrigerant sensor 56B. When the refrigerant sensor 56B receives the inspection signal SGM, it is set to a simulated leak state. A "simulated leak state" indicates a state in which a refrigerant leak is simulated. When the refrigerant sensor 56 is set to a simulated leak state, it outputs a simulated leak signal SGP to the indoor unit control unit 60B.

[0070] The second transmitting unit 72B transmits a response signal SGR to the indoor unit 50A when the second receiving unit 71B receives an inspection signal SGM from the indoor unit 50A and a false leak signal SGP from the refrigerant sensor 56B. The second transmitting unit 72B instructs the indoor unit communication circuit 61B to transmit a response signal SGR to the indoor unit communication circuit 61A located on the indoor unit 50A.

[0071] When the second transmission unit 72B is notified by the second execution unit 73B that the inspection of the safety device 6 corresponding to the indoor unit 50B has been completed, the second transmission unit 72B transmits an inspection completion signal SGE to the indoor unit 50A. The second transmitting unit 72B instructs the indoor unit communication circuit 61B to transmit an inspection completion signal SGE to the indoor unit communication circuit 61A located on the indoor unit 50A.

[0072] The second transmitting unit 72B transmits the abnormal signal SGA to the indoor unit 50A when the second executing unit 73B receives the abnormal signal SGA from at least one of the shut-off valve 8B and the alarm device 57B. The second transmitting unit 72B instructs the indoor unit communication circuit 61B to transmit an abnormal signal SGA to the indoor unit communication circuit 61A located on the indoor unit 50A.

[0073] When the second receiving unit 71B receives the inspection signal SGM, the second execution unit 73B transmits information to the second transmitting unit 72B indicating that the refrigerant sensor 56B is present and active, and that a response signal SGR has been received from the refrigerant sensor 56B. When the second receiving unit 71B receives the inspection signal SGM, if the refrigerant sensor 56B is not installed or the refrigerant sensor 56B is in an inactive state, the second execution unit 73B transmits information to the second transmission unit 72B indicating that it has not received a response signal SGR from the refrigerant sensor 56B.

[0074] The second execution unit 73B drives the equipment constituting the safety device 6 corresponding to the indoor unit 50B when the second receiving unit 71B receives the instruction signal SGC. The components of the safety device 6 include, for example, a shut-off valve 8B and an alarm 57B. The second execution unit 73B, for example, closes the shut-off valve 8B. The second execution unit 73B also, for example, causes the alarm device 57B to output a refrigerant leak alarm.

[0075] When the second execution unit 73B receives a normal signal SGN from the shut-off valve 8B and the alarm 57B, it notifies the second transmission unit 72B that the inspection of the safety device 6 corresponding to the indoor unit 50B has been completed. When the second execution unit 73B receives an abnormal signal SGA from at least one of the shut-off valve 8B and the alarm device 57B, it instructs the second transmission unit 72B to transmit the abnormal signal SGA to the indoor unit 50A.

[0076] [1-2. Operation] [1-2-1. Inspection Procedure for Safety Devices] Next, with reference to Figure 3, the inspection process for the safety device 6 performed by indoor units 50A, 50B, and 50C in Embodiment 1 will be described. Figure 3 is a flowchart showing the inspection process for the safety device 6 in Embodiment 1. Note that in the flowchart shown in Figure 3, for convenience, the explanation of what happens if an abnormality occurs in safety device 6 during inspection of safety device 6 has been omitted.

[0077] Steps S101 to S117 in Figure 3 are processes performed by the indoor unit control unit 60A of indoor unit 50A, which is set as the master unit, and steps S201 to S211 are processes performed by the indoor unit control unit 60B of indoor unit 50B, which is set as the slave unit. The processing performed by the indoor unit control unit 60B of indoor unit 50C, which is configured as a slave unit, is the same as the processing performed by the indoor unit control unit 60B of indoor unit 50B, which is configured as a slave unit. Therefore, in the following explanation, the processing performed by the indoor unit control unit 60B of indoor unit 50C, which is configured as a slave unit, will be described, and the explanation of the processing performed by the indoor unit control unit 60B of indoor unit 50C, which is configured as a slave unit, will be omitted.

[0078] The indoor unit control unit 60A of the indoor unit 50A, which is set as the master unit, executes the processes from steps S101 to S103. First, in step S101, the first transmitting unit 71A determines whether or not it has received an inspection start signal SGS from the remote control 90A indicating that the inspection of the safety device 6 should be started.

[0079] If the first transmitter 71A determines that it has not received the inspection start signal SGS (step S101; NO), the process enters a standby state. If the first transmitter 71A determines that it has received the inspection start signal SGS (step S101; YES), the process proceeds to step S103. Then, in step S103, the first transmitting unit 71A transmits an inspection signal SGM to the indoor unit 50B, the indoor unit 50C, and the refrigerant sensor 56A to indicate that the inspection should begin.

[0080] Next, the indoor unit control unit 60B of the indoor unit 50B, which is configured as a slave unit, executes the processes from steps S201 to S205. In step S201, the second receiving unit 71B determines whether or not it has received the inspection signal SGM transmitted from the indoor unit 50A. If the second receiver 71B determines that it has not received the inspection signal SGM transmitted from the indoor unit 50A (step S201; NO), the process enters a standby state. If the second receiver 71B determines that it has received the inspection signal SGM transmitted from the indoor unit 50A (step S201; YES), the second receiver 71B forwards the inspection signal SGM to the refrigerant sensor 56B, and the process proceeds to step S203.

[0081] Then, in step S203, the second transmitting unit 72B determines whether or not it has received a pseudo-leakage signal SGP from the refrigerant sensor 56B. The pseudo-leakage signal SGP indicates that the refrigerant sensor 56B has been set to a pseudo-leakage state. If the second transmitter 72B determines that it has not received a false leak signal SGP from the refrigerant sensor 56B (step S203; NO), the process enters a standby state. If the second transmitter 72B determines that it has received a false leak signal SGP from the refrigerant sensor 56B (step S203; YES), the process proceeds to step S205. Then, in step S205, the second transmitting unit 72B transmits a response signal SGR to the indoor unit 50A.

[0082] Next, the indoor unit control unit 60A of the indoor unit 50A, which is set as the master unit, executes the processes from steps S105 to S113. In step S105, the instruction unit 73A determines whether or not the first receiving unit 72A has received a response signal SGR indicating that it has received an inspection signal SGM from the indoor unit 50B, the indoor unit 50C, and the refrigerant sensor 56A. If the instruction unit 73A determines that it has received a response signal SGR from indoor unit 50B, indoor unit 50C, and refrigerant sensor 56A (step S105; YES), the process proceeds to step S111. If the instruction unit 73A determines that it has not received a response signal SGR from at least one of indoor unit 50B, indoor unit 50C, and refrigerant sensor 56A (step S105; NO), the process proceeds to step S107.

[0083] Then, in step S107, the instruction unit 73A determines whether a predetermined period of PD has elapsed since the first transmission unit 71A transmitted the inspection signal SGM. If the indicator unit 73A determines that the predetermined period PD has not elapsed (step S107; NO), the process returns to step S105. If the indicator unit 73A determines that the predetermined period PD has elapsed (step S107; YES), the process proceeds to step S109. Then, in step S109, the instruction unit 73A displays the error information on the display mechanism of the remote control 90A. After that, the process is terminated.

[0084] If the answer in step S105 is YES, then in step S111, the indicator unit 73A causes the display mechanism of the remote control 90A to display that the safety device 6 is in inspection status. Next, in step S113, the instruction unit 73A transmits an instruction signal SGC to the indoor units 50B and 50C, instructing them to drive the equipment constituting the safety device 6 corresponding to the indoor units 50B and 50C. The first execution unit 74A also drives the equipment constituting the safety device 6 corresponding to the indoor unit 50A.

[0085] Next, the indoor unit control unit 60B of the indoor unit 50B, which is configured as a slave unit, executes the processes from steps S207 to S211. In step S207, the second execution unit 73B determines whether the second receiving unit 71B has received the instruction signal SGC transmitted from the indoor unit 50A. If the second execution unit 73B determines that it has not received the instruction signal SGC (step S207; NO), the process enters a waiting state. If the second execution unit 73B determines that it has received the instruction signal SGC (step S207; YES), the process proceeds to step S209.

[0086] Then, in step S209, the second execution unit 73B drives the equipment that constitutes the safety device 6 corresponding to the indoor unit 50B. The equipment that constitutes the safety device 6 is, for example, a shut-off valve 8B and an alarm 57B. Next, in step S211, the second transmitting unit 72B transmits an inspection completion signal SGE to the indoor unit 50A when it is notified by the second executing unit 73B that the inspection of the safety device 6 corresponding to the indoor unit 50B has been completed.

[0087] Next, the indoor unit control unit 60A of the indoor unit 50A, which is set as the master unit, executes the processes from steps S115 to S117. In step S115, the instruction unit 73A determines whether the first receiving unit 72A has received an inspection completion signal SGE from the safety device 6 corresponding to indoor units 50B, 50C, and 50A. If the instruction unit 73A determines that it has not received an inspection completion signal SGE from at least one of the safety devices 6 corresponding to indoor units 50B, 50C, and 50A (step S115; NO), the process enters a standby state. If the instruction unit 73A determines that it has received an inspection completion signal SGE from the safety devices 6 corresponding to indoor units 50B, 50C, and 50A (step S115; YES), the process proceeds to step S117.

[0088] Then, in step S117, the instruction unit 73A causes the display mechanism of the remote control 90A to display that the inspection of the safety devices 6 corresponding to each of the three indoor units 50A, 50B, and 50C has been completed. After that, the process is terminated.

[0089] Step S103 corresponds to an example of the "transmission step". Step S105 corresponds to an example of a "receiving step". Step S111 corresponds to an example of an "instruction step".

[0090] [1-3. Effects, etc.] As described above, in Embodiment 1, the air conditioning system 1A has a plurality of indoor units 50 (50A, 50B, 50C) that are connected to each other in a manner that allows them to communicate with one another and are set as a first group GR1, and includes a safety device 6 that executes safety measures when a refrigerant sensor 56 detects a refrigerant leak, and a remote control 90A having an operating mechanism and a display mechanism, and when the refrigerant sensor 56 is located inside each of the plurality of indoor units 50, the indoor unit 50A set as the master unit among the plurality of indoor units 50 will inspect the safety device 6, and among the plurality of indoor units 50, all the other indoor units 50B, 50C The system includes a first transmitting unit 71A that transmits an inspection signal SGM to the refrigerant sensor 56A to start the inspection, a first receiving unit 72A that receives a response signal SGR from all other indoor units 50B, 50C and the refrigerant sensor 56A indicating that the inspection signal SGM has been received, and an instruction unit 73A that, when the first receiving unit 72A receives a response signal SGR from all other indoor units 50B, 50C and the refrigerant sensor 56A, causes the display mechanism of the remote control 90A to display that multiple indoor units 50 are in inspection status, the response signal SGR indicates that the refrigerant sensor 56 was set to a pseudo-leakage state when the inspection signal SGM was received.

[0091] With the above configuration, worker W can put the safety devices 6 corresponding to each of the multiple indoor units 50 (50A, 50B, 50C) set as the first group GR1 into an inspection state by issuing instructions to the indoor unit 50A, which is set as the master unit. Therefore, by operating the remote control 90A and inputting instructions to the indoor unit 50A, which is set as the master unit, worker W can easily inspect the safety devices 6 corresponding to each of the multiple indoor units 50 set as the first group GR1. Consequently, it is possible to reduce the workload on worker W during the inspection work of the safety devices 6. Furthermore, when a response signal SGR is received from all other indoor units 50B, 50C, and refrigerant sensor 56A, the display mechanism of the remote control 90A displays that multiple indoor units 50 are in inspection status. The response signal SGR indicates that the refrigerant sensor 56 has been set to a simulated leak state when the inspection signal SGM is received. Therefore, when the refrigerant sensor 56 is set to a simulated leak state, it is displayed that multiple indoor units 50 are in inspection status. Thus, with the correct configuration, it is possible to display that multiple indoor units 50 are in inspection status.

[0092] In the above-described air conditioning system 1A, the first transmitting unit 71A transmits an inspection signal SGM to all other indoor units 50B, 50C and the refrigerant sensor 56A located inside the indoor unit 50A designated as the master unit. The first receiving unit 72A receives a response signal SGR from all other indoor units 50B, 50C and the refrigerant sensor 56A. When the first receiving unit 72A receives the response signal SGR from all other indoor units 50B, 50C and the refrigerant sensor 56A, the display unit 73A causes the display mechanism of the remote control 90A to display that multiple indoor units 50 are in inspection status.

[0093] According to this, the first transmitter 71A, first receiver 72A, and instruction unit 73A of the indoor unit 50A, which is set as the master unit, can be made to perform the appropriate processing. Therefore, the safety devices 6 corresponding to each of the multiple indoor units 50 set as a group can be properly checked.

[0094] In the above-described air conditioning system 1A, the instruction unit 73A drives the equipment constituting the safety device 6 when the first receiving unit 72A receives a response signal SGR from all other indoor units 50B, 50C, and the refrigerant sensor 56A located inside indoor unit A, which is set as the master unit.

[0095] According to this, the devices (e.g., shut-off valve 8, alarm 57) that constitute the safety device 6 corresponding to each of the multiple indoor units 50 configured as a group can be properly driven. Therefore, the safety device 6 corresponding to each of the multiple indoor units 50 configured as a group can be properly inspected.

[0096] In the above-described air conditioning system 1A, each of the multiple indoor units 50 is equipped with a switching circuit 561 that switches between the enabled and disabled states of the refrigerant sensor 56. When indoor units 50B and 50C receive an inspection signal SGM, they transmit a response signal SGR to indoor unit 50A, which is set as the master unit, if the refrigerant sensor 56 is present and the refrigerant sensor 56 is enabled. When indoor units 50B and 50C receive an inspection signal SGM, they do not transmit a response signal SGR to indoor unit 50A, which is set as the master unit, if the refrigerant sensors 56B and 56C are not present or if the refrigerant sensors 56B and 56C are disabled.

[0097] According to this, when indoor units 50B and 50C receive the inspection signal SGM, they do not send a response signal SGR to indoor unit 50A, which is set as the master unit, if refrigerant sensors 56B and 56C are not installed or if refrigerant sensors 56B and 56C are in an inactive state. Therefore, it is possible to prevent the safety device 6 from transitioning to the inspection state when refrigerant sensors 56B and 56C are not in the proper state.

[0098] In the above-described air conditioning system 1A, the operating mechanism of the remote control 90A receives an inspection start operation QPS, which is an operation to start the inspection of the safety device 6, and an inspection end operation QPE, which is an operation to end the inspection of the safety device 6. The indoor unit 50A, which is set as the master unit, will not accept the inspection end operation QPE if an inspection end operation QPE is performed between the time the first receiving unit 72A receives the inspection start operation QPS and the time the first receiving unit 72A receives a response signal SGR from all other indoor units 50B, 50C, and the indoor unit 50A set as the master unit, if an inspection end operation QPE is performed.

[0099] According to this, it is possible to properly determine whether the indoor unit 50A, which is set as the master unit, accepts the inspection completion operation QPE. Therefore, it is possible to properly prohibit the completion of the inspection of the safety device 6 by the inspection completion operation QPE.

[0100] In the above-described air conditioning system 1A, the instruction unit 73A causes the first receiving unit 72A to display error information indicating the occurrence of an error on the display mechanism of the remote control 90A if, between the time the first transmitting unit 71A transmits the inspection signal SGM and a predetermined period PD has elapsed, the first receiving unit 72A does not receive a response signal SGR from at least one of the other indoor units 50B, 50C, and the indoor unit 50A designated as the master unit, which is located inside the refrigerant sensor 56A.

[0101] According to this, the instruction unit 73A of the indoor unit 50A, which is set as the master unit, can properly display error information indicating the occurrence of an error on the display mechanism of the remote control 90A. Therefore, the worker W can easily see that an error has occurred. Consequently, the workload on the worker W during the inspection of the safety device 6 can be reduced.

[0102] The control method for the air conditioning system 1A comprises a group of indoor units 50 (50A, 50B, 50C) that are connected to each other in a communicative manner and set up as a group, a safety device 6 that performs safety measures when a refrigerant sensor 56 detects a refrigerant leak, and a remote control 90A having an operating mechanism and a display mechanism. The control method for the air conditioning system 1 comprises a group of indoor units 50 (50A, 50B, 50C) that are connected to each other in a communicative manner and set up as a group, a safety device 6 that performs safety measures when a refrigerant sensor 56 detects a refrigerant leak, and a remote control 90A having an operating mechanism and a display mechanism. When the refrigerant sensor 56 is located inside each of the group of indoor units 50, the indoor unit 50A set up as the master unit among the group of indoor units 50 inspects the safety device 6, and all other indoor units 50B, 50C, and the refrigerant sensor The system performs the following steps: a transmission step of sending an inspection signal SGM to 56A to indicate that an inspection should be started; a reception step of receiving a response signal SGR from all other indoor units 50B, 50C and refrigerant sensor 56A indicating that the inspection signal SGM has been received; and an instruction step of, if the system receives a response signal SGR from all other indoor units 50B, 50C and refrigerant sensor 56A in the reception step, to display on the display mechanism of the remote control 90A that multiple indoor units 50 are in inspection mode, wherein the response signal SGR indicates that the refrigerant sensor 56 was set to a pseudo-leakage state when the inspection signal SGM was received.

[0103] According to this, the control method for the air conditioning system 1 produces the same effects as the air conditioning system 1 described above.

[0104] (Embodiment 2) [2-1. Structure] [2-1-1. Configuration of the air conditioning system] Next, with reference to Figure 4, the overall configuration of the air conditioning system 1B in Embodiment 2 will be described. Figure 4 is a diagram showing the overall configuration of the air conditioning system 1B in Embodiment 2. Referring to Figure 4, the differences between the air conditioning system 1B in Embodiment 2 and the air conditioning system 1A in Embodiment 1 shown in Figure 1 will be explained in detail.

[0105] In the first embodiment of the air conditioning system 1A shown in Figure 1, the case where each of the three indoor units 50 (indoor unit 50A, indoor unit 50B, and indoor unit 50C) is equipped with a refrigerant sensor 56 was described. In contrast, in the second embodiment of the air conditioning system 1B shown in Figure 4, the case where the refrigerant sensor 56 is located on the wall surface WS of room R1 will be described. The wall WS in room R1 corresponds to an example of "the exterior of multiple indoor units".

[0106] Embodiment 2 describes a case where the refrigerant sensor 56 is located on the wall surface WS of room R1, but the refrigerant sensor 56 may be located outside of multiple indoor units 50. For example, the refrigerant sensor 56 may be located on the ceiling of room R1. Alternatively, the refrigerant sensor 56 may be located on the floor of room R1. Alternatively, the refrigerant sensor 56 may be located on the remote control 90A corresponding to the indoor unit 50A.

[0107] Embodiment 2 describes a case where one refrigerant sensor 56 is placed on the wall surface WS of room R1, but multiple refrigerant sensors 56 may be placed on the wall surface WS of room R1. For example, two or more refrigerant sensors 56 may be placed on the wall surface WS of room R1 at different positions.

[0108] [2-1-2. Control System Configuration] Next, the configuration of the control system of the air conditioning system 1B will be described with reference to Figure 5. Figure 5 is a diagram showing the configuration of the indoor unit control unit 60 of multiple indoor units 50 in Embodiment 2. Figure 5 shows, for the sake of explanation, indoor unit 50A configured as the master unit, and indoor units 50B and 50C configured as slave units. The configurations of indoor units 50B and 50C are identical. Referring to Figure 5, the differences between the indoor unit control unit 60A of indoor unit 50A in Embodiment 2 and the indoor unit control unit 60A of indoor unit 50A in Embodiment 1 shown in Figure 2 will be mainly explained. Also, referring to Figure 5, the differences between the indoor unit control units 60B of indoor units 50B and indoor units 50C in Embodiment 2 and the indoor unit control units 60B of indoor units 50B and indoor units 50C in Embodiment 1 shown in Figure 2 will be mainly explained.

[0109] In Embodiment 1 shown in Figure 2, the case was described in which each of the indoor units 50A, 50B, and 50C is equipped with a switching circuit 561 for switching between the enabled and disabled states of the refrigerant sensor 56. In contrast, Embodiment 2 shown in Figure 5 differs in that it does not have a switching circuit 561 for switching between the enabled and disabled states of the refrigerant sensor 56 located on the wall WS of room R1.

[0110] Next, we will explain the configuration of the indoor unit control unit 60A of the indoor unit 50A, which is set as the master unit. The indoor unit 50A has a configuration similar to the indoor unit control unit 60A of the indoor unit 50A shown in Figure 2. In the indoor unit 50A, for example, the indoor unit processor 70A functions as a first transmission unit 71A, a first reception unit 72A, an instruction unit 73A, and a first execution unit 74A by reading and executing the indoor unit program 76A.

[0111] When inspecting the safety device 6, the first transmitting unit 71A transmits an inspection signal SGM to the refrigerant sensor 56 to indicate that the inspection should begin. The refrigerant sensor 56 is a refrigerant sensor located on the wall WS of room R1. The first transmitting unit 71A corresponds to an example of a "transmitting unit". Indoor units 50B and 50C correspond to examples of "all other indoor units".

[0112] The refrigerant sensor 56 is set to a pseudo-leakage state when it receives an inspection signal SGM from the first transmission unit 71A. When the refrigerant sensor 56 is set to a pseudo-leakage state, it outputs a pseudo-leakage signal SGP to the indoor unit control unit 60A. The pseudo-leakage signal SGP corresponds to an example of the response signal SGR.

[0113] When the first transmitter 71A receives an inspection start signal SGS from the remote control 90A indicating that it will start inspecting the safety device 6, it transmits an inspection signal SGM to the refrigerant sensor 56 indicating that it will start inspecting. The remote control 90A receives an inspection start operation QPS, which is an operation to start the inspection of the safety device 6. The inspection start operation QPS is, for example, the operation of the inspection start button located on the remote control 90A. When the remote control 90A receives the inspection start operation QPS, it transmits an inspection start signal SGS to the indoor unit control unit 60A.

[0114] The first receiving unit 72A receives a response signal SGR from the refrigerant sensor 56, indicating that it has received the inspection signal SGM. The first receiving unit 72A corresponds to an example of a "receiving unit".

[0115] The first receiving unit 72A receives an inspection completion signal SGE from the safety device 6 corresponding to the indoor units 50B, 50C, and 50A, indicating that the inspection has been completed.

[0116] When the first receiving unit 72A receives a response signal SGR indicating that it has received an inspection signal SGM from the refrigerant sensor 56, the instruction unit 73A causes the display mechanism of the remote control 90A to display that the safety devices 6 corresponding to each of the three indoor units 50A, 50B, and 50C are in an inspection state. Remote control 90A corresponds to an example of a "terminal device".

[0117] If the first receiving unit 72A does not receive a response signal SGR from at least one of the indoor units 50B, 50C, and refrigerant sensor 56 between the time the first transmitting unit 71A transmits an inspection signal SGM to the indoor units 50B, 50C, and 56 and the time a predetermined period PD has elapsed, the instruction unit 73A causes error information to be displayed on the display mechanism of the remote control 90A. The "error information" indicates, for example, that the refrigerant sensor 56 is malfunctioning. The predetermined period of PD is, for example, 3 minutes.

[0118] The remote control 90A, in accordance with instructions from the instruction unit 73A, displays on the display mechanism that at least one of the indoor units 50B, 50C, and refrigerant sensor 56 is malfunctioning. For example, if the remote control 90A does not receive a response signal SGR from the indoor unit 50B, it displays the message "Indoor unit 50B is malfunctioning." on a display such as an LCD.

[0119] When the first receiving unit 72A receives a response signal SGR indicating that it has received an inspection signal SGM from the indoor units 50B and 50C, the instruction unit 73A drives the equipment constituting the safety device 6 corresponding to the indoor units 50B and 50C.

[0120] The instruction unit 73A transmits an instruction signal SGC to the indoor unit 50B, for example, to instruct it to drive the equipment constituting the safety device 6 corresponding to the indoor unit 50B. The instruction unit 73A also transmits an instruction signal SGC to the indoor unit 50C, for example, to instruct it to drive the equipment constituting the safety device 6 corresponding to the indoor unit 50C. The components of the safety device 6 include, for example, a shut-off valve 8B and an alarm 57B.

[0121] When the first receiving unit 72A receives an inspection completion signal SGE from the safety devices 6 corresponding to indoor units 50B, 50C, and 50A, the instruction unit 73A causes the display mechanism of the remote control 90A to display that the inspection of the safety devices 6 corresponding to each of the three indoor units 50A, 50B, and 50C has been completed.

[0122] The remote control 90A, in accordance with instructions from the instruction unit 73A, displays on its display mechanism that the inspection of the safety devices 6 corresponding to each of the three indoor units 50A, 50B, and 50C has been completed. The remote control 90A displays the words "Safety device inspection completed" on a display such as an LCD.

[0123] When the first receiving unit 72A receives an abnormal signal SGA from at least one of the safety devices 6 corresponding to indoor units 50B, 50C, and 50A, the instruction unit 73A causes the display mechanism of the remote control 90A to display that an abnormality has occurred.

[0124] The remote control 90A, following instructions from the instruction unit 73A, displays on its display mechanism that an abnormality has occurred in the device corresponding to the address included in the abnormality signal SGA. For example, the remote control 90A displays the message, "An abnormality has occurred in the alarm 57B of the indoor unit 50B," on a display such as an LCD.

[0125] When the first receiver 72A receives a response signal SGR indicating that it has received an inspection signal SGM from the indoor unit 50B, the indoor unit 50C, and the refrigerant sensor 56, the first execution unit 74A drives the equipment constituting the safety device 6 corresponding to the indoor unit 50A. The components of the safety device 6 include, for example, a shut-off valve 8A and an alarm 57A. The first execution unit 74A, for example, closes the shut-off valve 8A. The first execution unit 74A also, for example, causes the alarm device 57A to output a refrigerant leak alarm.

[0126] When the first execution unit 74A receives a normal signal SGN from the shut-off valve 8A and the alarm 57A, it notifies the first receiving unit 72A that the inspection of the safety device 6 corresponding to the indoor unit 50A has been completed. For example, when the first execution unit 74A receives a normal signal SGN from the shut-off valve 8A and the alarm 57A, it notifies the first receiving unit 72A that it has received an inspection completion signal SGE from the safety device 6 corresponding to the indoor unit 50A.

[0127] Next, we will explain the functional configuration of indoor units 50B and 50C, which are configured as slave units. For convenience, in the following explanation, we will describe indoor unit 50B, and omit the explanation of indoor unit 50C. The indoor unit processor 70 functions as a second receiving unit 71B, a second transmitting unit 72B, and a second execution unit 73B by reading and executing the indoor unit program 76B.

[0128] The second receiving unit 71B receives the inspection signal SGM transmitted from the indoor unit 50A. The second receiving unit 71B receives the instruction signal SGC transmitted from the indoor unit 50A.

[0129] When the second receiver 71B receives an inspection signal SGM from the indoor unit 50A, the second transmitter 72B transmits a response signal SGR to the indoor unit 50A.

[0130] When the second transmission unit 72B is notified by the second execution unit 73B that the inspection of the safety device 6 corresponding to the indoor unit 50B has been completed, the second transmission unit 72B transmits an inspection completion signal SGE to the indoor unit 50A.

[0131] The second transmitting unit 72B transmits the abnormal signal SGA to the indoor unit 50A when the second executing unit 73B receives the abnormal signal SGA from at least one of the shut-off valve 8B and the alarm device 57B.

[0132] The second execution unit 73B drives the equipment constituting the safety device 6 corresponding to the indoor unit 50B when the second receiving unit 71B receives the instruction signal SGC. The components of the safety device 6 include, for example, a shut-off valve 8B and an alarm 57B. The second execution unit 73B, for example, closes the shut-off valve 8B. The second execution unit 73B also, for example, causes the alarm device 57B to output a refrigerant leak alarm.

[0133] When the second execution unit 73B receives a normal signal SGN from the shut-off valve 8B and the alarm 57B, it notifies the second transmission unit 72B that the inspection of the safety device 6 corresponding to the indoor unit 50B has been completed. When the second execution unit 73B receives an abnormal signal SGA from at least one of the shut-off valve 8B and the alarm device 57B, it instructs the second transmission unit 72B to transmit the abnormal signal SGA to the indoor unit 50A.

[0134] [2-2. Operation] [2-2-1. Inspection Procedure for Safety Devices] Next, with reference to Figure 6, the inspection process of the safety device 6 performed by indoor units 50A, 50B, and 50C in Embodiment 2 will be described. Figure 6 is a flowchart showing the inspection process of the safety device 6 in Embodiment 2. Note that in the flowchart shown in Figure 6, for convenience, the explanation of what happens if an abnormality occurs in safety device 6 during inspection of safety device 6 has been omitted.

[0135] Steps S301 to S317 in Figure 6 are processes performed by the indoor unit control unit 60A of the indoor unit 50A configured as the master unit, and steps S405 to S409 are processes performed by the indoor unit control unit 60B of the indoor unit 50B configured as the slave unit. The processing performed by the indoor unit control unit 60B of indoor unit 50C, which is configured as a slave unit, is the same as the processing performed by the indoor unit control unit 60B of indoor unit 50B, which is configured as a slave unit. Therefore, in the following explanation, the processing performed by the indoor unit control unit 60B of indoor unit 50C, which is configured as a slave unit, will be described, and the explanation of the processing performed by the indoor unit control unit 60B of indoor unit 50C, which is configured as a slave unit, will be omitted.

[0136] The indoor unit control unit 60A of the indoor unit 50A, which is set as the master unit, executes the processes from steps S101 to S103. First, in step S101, the first transmitting unit 71A determines whether or not it has received an inspection start signal SGS from the remote control 90A indicating that the inspection of the safety device 6 should be started.

[0137] If the first transmitter 71A determines that it has not received the inspection start signal SGS (step S101; NO), the process enters a standby state. If the first transmitter 71A determines that it has received the inspection start signal SGS (step S101; YES), the process proceeds to step S103. Then, in step S103, the first transmitting unit 71A transmits an inspection signal SGM to the refrigerant sensor 56 to indicate that the inspection should begin.

[0138] Next, the refrigerant sensor 56 performs the processes shown in steps S401 to S403 (not shown in the figure). In step S401, the refrigerant sensor 56 determines whether or not it has received the inspection signal SGM transmitted from the indoor unit 50A. If the refrigerant sensor 56 determines that it has not received the inspection signal SGM transmitted from the indoor unit 50A (step S401; NO), the process enters a standby state. If the refrigerant sensor 56 determines that it has received the inspection signal SGM transmitted from the indoor unit 50A (step S401; YES), the process proceeds to step S403. Then, in step S403, the refrigerant sensor 56 transmits a response signal SGR to the indoor unit 50A.

[0139] Next, the indoor unit control unit 60A of the indoor unit 50A, which is set as the master unit, executes the processes from steps S305 to S313. In step S305, the instruction unit 73A determines whether or not the first receiving unit 72A has received a response signal SGR indicating that it has received an inspection signal SGM from the refrigerant sensor 56. If the indicator unit 73A determines that it has received a response signal SGR from the refrigerant sensor 56 (step S305; YES), the process proceeds to step S311. If the indicator unit 73A determines that it has not received a response signal SGR from the refrigerant sensor 56 (step S305; NO), the process proceeds to step S307.

[0140] Then, in step S307, the instruction unit 73A determines whether a predetermined period of time PD has elapsed since the first transmission unit 71A transmitted the inspection signal SGM. If the indicator unit 73A determines that the predetermined period PD has not elapsed (step S307; NO), the process returns to step S305. If the indicator unit 73A determines that the predetermined period PD has elapsed (step S307; YES), the process proceeds to step S309. Then, in step S309, the instruction unit 73A displays the error information on the display mechanism of the remote control 90A. After that, the process is terminated.

[0141] If the answer in step S305 is YES, then in step S311, the indicator unit 73A causes the display mechanism of the remote control 90A to display that the safety device 6 is in inspection status. Next, in step S313, the instruction unit 73A transmits an instruction signal SGC to indoor units 50B and 50C, instructing them to drive the equipment constituting the safety device 6 corresponding to indoor units 50B and 50C. The first execution unit 74A also drives the equipment constituting the safety device 6 corresponding to indoor unit 50A.

[0142] Next, the indoor unit control unit 60B of the indoor unit 50B, which is configured as a slave unit, executes the processes from steps S405 to S409. In step S405, the second execution unit 73B determines whether the second receiving unit 71B has received the instruction signal SGC transmitted from the indoor unit 50A. If the second execution unit 73B determines that it has not received the instruction signal SGC (step S405; NO), the process enters a waiting state. If the second execution unit 73B determines that it has received the instruction signal SGC (step S405; YES), the process proceeds to step S407.

[0143] Then, in step S407, the second execution unit 73B drives the equipment that constitutes the safety device 6 corresponding to the indoor unit 50B. The equipment that constitutes the safety device 6 is, for example, a shut-off valve 8B and an alarm 57B. Next, in step S409, the second transmitting unit 72B transmits an inspection completion signal SGE to the indoor unit 50A when it is notified by the second executing unit 73B that the inspection of the safety device 6 corresponding to the indoor unit 50B has been completed.

[0144] Next, the indoor unit control unit 60A of the indoor unit 50A, which is set as the master unit, executes the processes from steps S315 to S317. In step S315, the instruction unit 73A determines whether the first receiving unit 72A has received an inspection completion signal SGE from the safety device 6 corresponding to indoor unit 50B, indoor unit 50C, and indoor unit 50A. If the instruction unit 73A determines that it has not received an inspection completion signal SGE from at least one of the safety devices 6 corresponding to indoor units 50B, 50C, and 50A (step S315; NO), the process enters a standby state. If the instruction unit 73A determines that it has received an inspection completion signal SGE from the safety devices 6 corresponding to indoor units 50B, 50C, and 50A (step S315; YES), the process proceeds to step S317.

[0145] Then, in step S317, the instruction unit 73A causes the display mechanism of the remote control 90A to indicate that the inspection of the safety devices 6 corresponding to each of the three indoor units 50A, 50B, and 50C has been completed. After that, the process is terminated.

[0146] Step S303 corresponds to an example of a "transmission step". Step S305 corresponds to an example of a "receiving step". Step S311 corresponds to an example of an "instruction step".

[0147] [2-3. Effects, etc.] As described above, in Embodiment 2, the air conditioning system 1B is an air conditioning system 1B having a plurality of indoor units 50 (50A, 50B, 50C) that are connected to each other in a manner that allows communication and are set as a first group GR1, and includes a safety device 6 that performs safety measures when a refrigerant sensor 56 detects a refrigerant leak, and a remote control 90A having an operating mechanism and a display mechanism, and when the refrigerant sensor 56 is located outside the plurality of indoor units 50, the indoor unit 50A set as the master unit among the plurality of indoor units 50 has a first transmitting unit 71A that transmits an inspection signal SGM to the refrigerant sensor 56 among the plurality of indoor units 50 to start the inspection when inspecting the safety device 6, a first receiving unit 72A that receives a response signal SGR from the refrigerant sensor 56 indicating that it has received the inspection signal SGM, and an instruction unit 73A that, when the first receiving unit 72A receives the response signal SGR from the refrigerant sensor 56, causes the display mechanism of the remote control 90A to display that the plurality of indoor units 50 are in an inspection state.

[0148] With the above configuration, worker W can put the safety devices 6 corresponding to each of the multiple indoor units 50 (50A, 50B, 50C) set as the first group GR1 into an inspection state by issuing instructions to the indoor unit 50A, which is set as the master unit. Therefore, by operating the remote control 90A and inputting instructions to the indoor unit 50A, which is set as the master unit, worker W can easily inspect the safety devices 6 corresponding to each of the multiple indoor units 50 set as the first group GR1. Consequently, it is possible to reduce the workload on worker W during the inspection work of the safety devices 6. Furthermore, when a response signal SGR is received from the refrigerant sensor 56, the display mechanism of the remote control 90A displays that multiple indoor units 50 are in inspection status. The response signal SGR indicates that the refrigerant sensor 56 has been set to a simulated leak state when the inspection signal SGM is received. Therefore, when the refrigerant sensor 56 is set to a simulated leak state, it is displayed that multiple indoor units 50 are in inspection status. Thus, with the correct configuration, it is possible to display that multiple indoor units 50 are in inspection status.

[0149] In the above-described air conditioning system 1B, the first transmitting unit 71A transmits an inspection signal SGM to the refrigerant sensor 56, the first receiving unit 72A receives a response signal SGR from the refrigerant sensor 56, and the indicator unit 73A, when the first receiving unit 72A receives the response signal SGR from the refrigerant sensor 56, displays on the display mechanism of the remote control 90A that multiple indoor units 50 are in inspection status.

[0150] According to this, the first transmitter 71A, first receiver 72A, and instruction unit 73A of the indoor unit 50A, which is set as the master unit, can be made to perform the appropriate processing. Therefore, the safety devices 6 corresponding to each of the multiple indoor units 50 set as a group can be properly checked.

[0151] In the above-described air conditioning system 1B, the indicator unit 73A drives the equipment constituting the safety device 6 when the first receiving unit 72A receives a response signal SGR from the refrigerant sensor 56.

[0152] According to this, the devices (e.g., shut-off valve 8, alarm 57) that constitute the safety device 6 corresponding to each of the multiple indoor units 50 configured as a group can be properly driven. Therefore, the safety device 6 corresponding to each of the multiple indoor units 50 configured as a group can be properly inspected.

[0153] In the above-described air conditioning system 1B, the operating mechanism of the remote control 90A receives an inspection start operation QPS, which is an operation to start the inspection of the safety device 6, and an inspection end operation QPE, which is an operation to end the inspection of the safety device 6. If an inspection end operation QPE is performed between the time the inspection start operation QPS is received and the time the first receiving unit 72A receives a response signal SGR from the refrigerant sensor 56, the remote control 90A does not accept the inspection end operation QPE.

[0154] According to this, it is possible to properly determine whether the indoor unit 50A, which is set as the master unit, accepts the inspection completion operation QPE. Therefore, it is possible to properly prohibit the completion of the inspection of the safety device 6 by the inspection completion operation QPE.

[0155] In the above-described air conditioning system 1B, the instruction unit 73A causes the first receiving unit 72A to display error information indicating the occurrence of an error on the display mechanism of the remote control 90A if the first receiving unit 72A does not receive a response signal SGR from the refrigerant sensor 56 between the time the first transmitting unit 71A transmits the inspection signal SGM and the time a predetermined period PD has elapsed.

[0156] According to this, the instruction unit 73A of the indoor unit 50A, which is set as the master unit, can properly display error information indicating the occurrence of an error on the display mechanism of the remote control 90A. Therefore, the worker W can easily see that an error has occurred. Consequently, the workload on the worker W during the inspection of the safety device 6 can be reduced.

[0157] The control method for the air conditioning system 1B comprises a plurality of indoor units 50 (50A, 50B, 50C) connected to each other in a communicative manner and set up as a group, a safety device 6 that performs safety measures when a refrigerant sensor 56 detects a refrigerant leak, and a remote control 90A having an operating mechanism and a display mechanism. The control method for the air conditioning system 1 is configured such that when the refrigerant sensor 56 is located outside the plurality of indoor units 50, the indoor unit 50A, which is set up as the master unit among the plurality of indoor units 50, performs a transmission step of sending an inspection signal SGM to the refrigerant sensor 56 among the plurality of indoor units 50 to start the inspection when inspecting the safety device 6, a reception step of receiving a response signal SGR from the refrigerant sensor 56 to indicate that the inspection signal SGM has been received, and an instruction step of displaying on the display mechanism of the remote control 90A that the plurality of indoor units 50 are in an inspection state when the response signal SGR is received from the refrigerant sensor 56 in the reception step, and the response signal SGR indicates that the refrigerant sensor 56 was set to a pseudo-leak state when the inspection signal SGM was received.

[0158] According to this, the control method for the air conditioning system 1B produces the same effect as the air conditioning system 1B described above.

[0159] (Other embodiments) As described above, the above embodiments have been explained as examples of the technology disclosed in this application. However, the technology in this disclosure is not limited to these embodiments and can be applied to embodiments that have been modified, replaced, added, or omitted. Therefore, other embodiments will be described below as examples.

[0160] In the above embodiment, the case in which the air conditioning system 1 is equipped with three indoor units 50 (indoor unit 50A, indoor unit 50B, and indoor unit 50C) was described, but there may be two indoor units 50, or four or more. Furthermore, although the above embodiment described a case in which three indoor units 50 (indoor unit 50A, indoor unit 50B, and indoor unit 50C) constitute the first group GR1, any number of indoor units 50 can constitute the first group GR1. For example, two indoor units 50 may constitute the first group GR1, or four or more indoor units 50 may constitute the first group GR1. Similarly, the multiple indoor units 50 that make up the second group can consist of two or more indoor units 50.

[0161] In the above embodiment, the case in which indoor unit 50A is set as the master unit and indoor units 50B and 50C are set as slave units has been described, but the embodiment is not limited to this. For example, indoor unit 50B may be set as the master unit, and indoor units 50A and 50C may be set as slave units. Alternatively, for example, indoor unit 50C may be set as the master unit, and indoor units 50A and 50B may be set as slave units.

[0162] In the above embodiment, the case in which the alarm 57 is located inside the indoor unit 50 was described, but the alarm 57 may also be located separately from the indoor unit 50.

[0163] In the above embodiment, the case where the "terminal device" is the remote control 90A is described, but the embodiment is not limited to this. The "terminal device" may be, for example, a computer that is communicatively connected to the indoor unit control unit 60A. The "terminal device" may be, for example, a so-called centralized management device. The "terminal device" may also be a personal computer, a tablet computer, or a smartphone. The "terminal device" may also be a work remote control carried by the worker W.

[0164] Each of the indoor unit processors 70 may consist of a single processor or multiple processors. These processors may also be hardware programmed to implement the corresponding functional units. That is, these processors may consist of, for example, an ASIC (Application Specific Integrated Circuit) or an FPGA (Field Programmable Gate Array).

[0165] Each of the indoor unit communication circuits 61 may perform wireless communication. For wireless connection, standards such as Wi-Fi (registered trademark) and WiMAX (registered trademark) can be used.

[0166] In the flowcharts shown in Figures 3 and 6, the processing steps of the indoor unit control unit 60A of the indoor unit 50A configured as the master unit, and the indoor unit control unit 60B of the indoor unit 50B configured as the slave unit, are divided according to their main processing content to facilitate understanding of the operation. The operation is not limited by the way the processing units are divided or the names of the divisions. Depending on the processing content, the process may be further divided into more steps. Alternatively, a single step unit may be divided to include even more processing. Furthermore, the order of the steps may be rearranged as appropriate, as long as it does not impede the intent of this disclosure.

[0167] Since the embodiments described above are for illustrative purposes of the technology described herein, various modifications, substitutions, additions, omissions, etc., can be made within the scope of the claims or equivalents thereof.

[0168] (Note) Based on the above description of embodiments, the following technologies are disclosed.

[0169] (Technology 1) An air conditioning system having a plurality of indoor units connected to each other in a communicative manner and configured as a group, comprising: a safety device that performs safety measures when a refrigerant sensor detects a refrigerant leak; and a terminal device having an operating mechanism and a display mechanism, wherein when the refrigerant sensor is located inside each of the plurality of indoor units, the indoor unit configured as the master unit among the plurality of indoor units, when inspecting the safety device, transmits an inspection signal to all other indoor units among the plurality of indoor units and the refrigerant sensor indicating that an inspection has been started; receives a response signal from all other indoor units and the refrigerant sensor indicating that the inspection signal has been received; and when the receiving unit receives the response signal from all other indoor units and the refrigerant sensor, it causes the display mechanism of the terminal device to display that the plurality of indoor units are in an inspection state, wherein the response signal indicates that the refrigerant sensor has been set to a pseudo-leak state when the inspection signal was received.

[0170] With this configuration, an operator can put the safety devices corresponding to each of the multiple indoor units configured as a group into inspection mode by issuing instructions to the indoor unit set as the master unit. Therefore, by operating the terminal device and inputting instructions to the indoor unit set as the master unit, the operator can easily inspect the safety devices corresponding to each of the multiple indoor units configured as a group. Consequently, the workload on the operator during the safety device inspection work can be reduced. Furthermore, when response signals are received from all other indoor units and refrigerant sensors, the terminal device's display mechanism will indicate that multiple indoor units are in inspection status. The response signal indicates that the refrigerant sensor was set to a simulated leak state when the inspection signal was received. Therefore, when the refrigerant sensor is set to a simulated leak state, the system will display that multiple indoor units are in inspection status. Thus, with the correct configuration, it is possible to display that multiple indoor units are in inspection status.

[0171] (Technology 2) The air conditioning system according to Technology 1, wherein the transmitting unit transmits the inspection signal to all the other indoor units and to the master refrigerant sensor which is a refrigerant sensor located inside the indoor unit set as the master unit, the receiving unit receives the response signal from all the other indoor units and the master refrigerant sensor, and the instruction unit causes the display mechanism of the terminal device to display that the multiple indoor units are in inspection status when the receiving unit receives the response signal from all the other indoor units and the master refrigerant sensor.

[0172] This configuration allows the transmitter, receiver, and instruction units of the indoor unit configured as the master unit to perform appropriate processing. Therefore, the safety devices corresponding to each of the multiple indoor units configured as a group can be properly checked.

[0173] (Technology 3) The air conditioning system according to Technology 1 or Technology 2, wherein the instruction unit drives the equipment constituting the safety device when the receiving unit receives the response signal from all the other indoor units and from the master refrigerant sensor, which is a refrigerant sensor located inside the indoor unit designated as the master unit.

[0174] This configuration allows for the proper operation of the safety devices corresponding to each of the multiple indoor units configured as a group. Therefore, the safety devices corresponding to each of the multiple indoor units configured as a group can be properly inspected.

[0175] (Technology 4) An air conditioning system according to any one of the technologies 1 to 3, wherein each of the plurality of indoor units is equipped with a switching circuit for switching between the enabled and disabled states of the refrigerant sensor, and when an indoor unit receives the inspection signal, if the refrigerant sensor is present and the refrigerant sensor is in the enabled state, it transmits the response signal to the indoor unit set as the master unit, and when an indoor unit receives the inspection signal, if the refrigerant sensor is not present or the refrigerant sensor is in the disabled state, it does not transmit the response signal to the indoor unit set as the master unit.

[0176] With this configuration, if an indoor unit that receives an inspection signal does not have a refrigerant sensor installed or the refrigerant sensor is disabled, it will not send a response signal to the indoor unit set as the master unit. This prevents the safety device from switching to inspection mode when the refrigerant sensor is not in the correct state.

[0177] (Technology 5) The operating mechanism of the terminal device receives an inspection start operation, which is an operation to start the inspection of the safety device, and an inspection end operation, which is an operation to end the inspection of the safety device, and the indoor unit set as the master unit does not accept the inspection end operation if the inspection end operation is performed between the time the receiving unit receives the inspection start operation and the time the receiving unit receives the response signal from all the other indoor units and the master unit refrigerant sensor, which is a refrigerant sensor located inside the indoor unit set as the master unit, the air conditioning system according to any one of the technologies 1 to 4.

[0178] This configuration allows the indoor unit, which is set as the master unit, to properly determine whether or not to accept the inspection completion operation. Therefore, it is possible to properly prohibit the termination of the safety device inspection by the inspection completion operation.

[0179] (Technology 6) The air conditioning system according to any one of Techniques 1 to 5, wherein the instruction unit causes the receiving unit to display error information indicating the occurrence of an error on the display mechanism of the terminal device if, within a predetermined period from the time the transmitting unit transmits the inspection signal, the receiving unit does not receive the response signal from at least one of the other indoor units and the master refrigerant sensor which is a refrigerant sensor located inside the indoor unit designated as the master unit.

[0180] With this configuration, the instruction unit of the indoor unit, which is set as the master unit, can properly display error information indicating the occurrence of an error on the display mechanism of the terminal device. Therefore, the operator can easily see when an error has occurred. Consequently, the workload on the operator during safety device inspection work can be reduced.

[0181] (Technology 7) An air conditioning system having a plurality of indoor units connected to each other in a communicative manner and configured as a group, comprising: a safety device that performs safety measures when a refrigerant sensor detects a refrigerant leak; and a terminal device having an operating mechanism and a display mechanism, wherein when the refrigerant sensor is located outside the plurality of indoor units, the indoor unit configured as the master unit among the plurality of indoor units shall, when inspecting the safety device, have a transmitting unit that transmits an inspection signal to the refrigerant sensor indicating that an inspection has been started; a receiving unit that receives a response signal from the refrigerant sensor indicating that the inspection signal has been received; and an instruction unit that, when the receiving unit receives the response signal from the refrigerant sensor, causes the display mechanism of the terminal device to display that the plurality of indoor units are in an inspection state, wherein the response signal indicates that the refrigerant sensor has been set to a pseudo-leak state when the inspection signal was received.

[0182] With this configuration, an operator can put the safety devices corresponding to each of the multiple indoor units configured as a group into inspection mode by issuing instructions to the indoor unit set as the master unit. Therefore, by operating the terminal device and inputting instructions to the indoor unit set as the master unit, the operator can easily inspect the safety devices corresponding to each of the multiple indoor units configured as a group. Consequently, the workload on the operator during the safety device inspection work can be reduced. Furthermore, when a response signal is received from the refrigerant sensor, the terminal device's display mechanism will show that multiple indoor units are in inspection mode. The response signal indicates that the refrigerant sensor has been set to a simulated leak state when the inspection signal is received. Therefore, when the refrigerant sensor is set to a simulated leak state, the system will show that multiple indoor units are in inspection mode. Thus, with the correct configuration, it is possible to display that multiple indoor units are in inspection mode.

[0183] (Technology 8) The air conditioning system according to Technical Reference 7, wherein the transmitting unit transmits the inspection signal to the refrigerant sensor, the receiving unit receives the response signal from the refrigerant sensor, and the instruction unit, when the receiving unit receives the response signal from the refrigerant sensor, causes the display mechanism of the terminal device to display that the multiple indoor units are in inspection status.

[0184] This configuration allows the transmitter, receiver, and instruction units of the indoor unit configured as the master unit to perform appropriate processing. Therefore, the safety devices corresponding to each of the multiple indoor units configured as a group can be properly checked.

[0185] (Technology 9) The air conditioning system according to Technology 7 or Technology 8, wherein the instruction unit drives the equipment constituting the safety device when the receiving unit receives the response signal from the refrigerant sensor.

[0186] This configuration allows for the proper operation of the safety devices corresponding to each of the multiple indoor units configured as a group. Therefore, the safety devices corresponding to each of the multiple indoor units configured as a group can be properly inspected.

[0187] (Technology 10) The operating mechanism of the terminal device receives an inspection start operation, which is an operation to start the inspection of the safety device, and an inspection end operation, which is an operation to end the inspection of the safety device, and if the inspection end operation is performed between the time the inspection start operation is received and the time the receiving unit receives the response signal from the refrigerant sensor, the inspection end operation is not received, the air conditioning device according to any one of the technologies 7 to 9.

[0188] This configuration allows the indoor unit, which is set as the master unit, to properly determine whether or not to accept the inspection completion operation. Therefore, it is possible to properly prohibit the termination of the safety device inspection by the inspection completion operation.

[0189] (Technology 11) The air conditioning system according to any one of the technologies 7 to 10, wherein the instruction unit causes the receiving unit to display error information indicating the occurrence of an error on the display mechanism of the terminal device if the receiving unit does not receive the response signal from the refrigerant sensor within a predetermined period from the time the transmitting unit transmits the inspection signal until a predetermined period has elapsed.

[0190] With this configuration, the instruction unit of the indoor unit, which is set as the master unit, can properly display error information indicating the occurrence of an error on the display mechanism of the terminal device. Therefore, the operator can easily see when an error has occurred. Consequently, the workload on the operator during safety device inspection work can be reduced.

[0191] (Technology 12) A control method for an air conditioning system comprising: a plurality of indoor units connected to each other in a communicative manner and configured as a group; a safety device that performs safety measures when a refrigerant sensor detects a refrigerant leak; and a terminal device having an operating mechanism and a display mechanism, wherein, when the refrigerant sensor is located inside each of the plurality of indoor units, the indoor unit configured as the master unit among the plurality of indoor units performs a transmission step of transmitting an inspection signal to all other indoor units among the plurality of indoor units and the refrigerant sensor to indicate that an inspection has been started when inspecting the safety device; a reception step of receiving a response signal from all other indoor units and the refrigerant sensor indicating that the inspection signal has been received; and, in the reception step, when the response signal has been received from all other indoor units and the refrigerant sensor, an instruction step of causing the display mechanism of the terminal device to display that the plurality of indoor units are in an inspection state, wherein the response signal indicates that the refrigerant sensor was set to a pseudo-leak state when the inspection signal was received.

[0192] This configuration produces the same effect as the air conditioning system of Technology 1.

[0193] (Technology 13) A control method for an air conditioning system comprising: a plurality of indoor units connected to each other in a communicative manner and configured as a group; a safety device that performs safety measures when a refrigerant sensor detects a refrigerant leak; and a terminal device having an operating mechanism and a display mechanism, wherein when the refrigerant sensor is located outside the plurality of indoor units, the indoor unit configured as the master unit among the plurality of indoor units performs a transmission step of transmitting an inspection signal to the refrigerant sensor to indicate that an inspection should be started when inspecting the safety device; a reception step of receiving a response signal from the refrigerant sensor indicating that the inspection signal has been received; and, in the reception step, when the response signal is received from the refrigerant sensor, an instruction step of causing the display mechanism of the terminal device to display that the plurality of indoor units are in an inspection state, wherein the response signal indicates that the refrigerant sensor was set to a pseudo-leak state when the inspection signal was received.

[0194] This configuration produces the same effect as the air conditioning system of Technology 7. [Industrial applicability]

[0195] This disclosure is applicable to applications that reduce the workload on workers during inspection work of safety devices. [Explanation of Symbols]

[0196] 1A, 1B, 1 Air conditioning unit 10 Outdoor unit 20 Outdoor unit control unit 50A, 50 Indoor unit (master unit) 60A Indoor Unit Control Unit 61A Indoor unit communication circuit 70A Indoor Unit Processor 71A First Transmitter (Transmitter) 72A First receiving unit (receiving unit) 73A Instruction section 74A First Execution Unit 75A Indoor Unit Memory 76A Indoor Unit Program 50B, 50C, 50 Indoor Unit (Slave Unit, all other indoor units) 60B Indoor Unit Control Unit 61B Indoor unit communication circuit 70B Indoor Unit Processor 71B Second Receiver 72B Second Transmitter 73B Second Executive Unit 75B Indoor Unit Memory 76B Indoor Unit Program 6 Safety equipment 56A, 56B, 56C, 56 Refrigerant Sensor (part of the safety device) 56A Refrigerant Sensor (Master Unit Refrigerant Sensor) 561A, 561B, 561C, 561 switching circuit 56B, 56C refrigerant sensors 57A, 57B, 57C, 57 Alarm devices (part of safety devices) 8A, 8B, 8C, 8 Shut-off valves (part of the safety device) 80 First shut-off valve 81 Second shut-off valve 90B, 90C, 90 Remote Control 90A Remote control (terminal device) GR1 Group 1 PD predetermined period SGA abnormal signal SGC instruction signal SGE inspection completion signal SGM Inspection Signal SGN normal signal SGP Pseudo-Leakage Signal (Response Signal) SGR response signal SGS Inspection Start Signal W Worker WS Wall (exterior of multiple indoor units)

Claims

1. An air conditioning system having multiple indoor units that are connected to each other in a way that allows them to communicate with one another and are configured as a group, A safety device that takes safety measures when a refrigerant sensor detects a refrigerant leak, A terminal device having an operating mechanism and a display mechanism, Equipped with, When the refrigerant sensor is located inside each of the multiple indoor units, Of the aforementioned multiple indoor units, the indoor unit designated as the master unit is: A transmitting unit that, when inspecting the safety device, transmits an inspection signal to all other indoor units and the refrigerant sensor among the multiple indoor units to indicate that the inspection has begun. A receiving unit that receives a response signal indicating that the inspection signal has been received from all the other indoor units and the refrigerant sensor, When the receiving unit receives the response signals from all the other indoor units and the refrigerant sensor, the instruction unit causes the display mechanism of the terminal device to display that the multiple indoor units are in inspection status. Equipped with, The response signal indicates that the refrigerant sensor has been set to a pseudo-leakage state when the inspection signal is received, according to the air conditioning system.

2. The transmitting unit transmits the inspection signal to all other indoor units and to the master refrigerant sensor, which is a refrigerant sensor located inside the indoor unit designated as the master unit. The receiving unit receives the response signal from all the other indoor units and the master unit refrigerant sensor. When the receiving unit receives the response signals from all the other indoor units and the master unit refrigerant sensor, the instruction unit causes the display mechanism of the terminal device to display that the multiple indoor units are in inspection status. The response signal indicates that, upon receiving the inspection signal, each of the refrigerant sensors located in all other indoor units and the master unit refrigerant sensor has been set to a simulated leakage state. The air conditioning device according to claim 1.

3. The instruction unit drives the equipment constituting the safety device when the receiving unit receives the response signal from all the other indoor units and from the master refrigerant sensor, which is a refrigerant sensor located inside the indoor unit designated as the master unit. An air conditioning device according to claim 1 or claim 2.

4. Each of the aforementioned multiple indoor units is equipped with a switching circuit for switching between the enabled and disabled states of the refrigerant sensor. Upon receiving the inspection signal, the indoor unit, if it has a refrigerant sensor and the refrigerant sensor is in the effective state, transmits the response signal to the indoor unit designated as the master unit. If the indoor unit that receives the inspection signal does not have a refrigerant sensor installed, or if the refrigerant sensor is in the disabled state, it will not transmit the response signal to the indoor unit set as the master unit. An air conditioning device according to claim 1 or claim 2.

5. The operating mechanism of the terminal device receives an inspection start operation, which is an operation to start the inspection of the safety device, and an inspection end operation, which is an operation to end the inspection of the safety device. If the refrigerant sensor is located inside each of the multiple indoor units, If the inspection completion operation is performed between the time the indoor unit designated as the master unit receives the inspection start operation and the time the receiving unit receives the response signal from all other indoor units and the master unit refrigerant sensor located inside the indoor unit designated as the master unit, the master unit will not accept the inspection completion operation. An air conditioning device according to claim 1 or claim 2.

6. The instruction unit, if the receiving unit does not receive the response signal from any of the other indoor units and any of the master refrigerant sensors located inside the indoor unit designated as the master unit within a predetermined period of time from the time the transmitting unit transmits the inspection signal, causes the display mechanism of the terminal device to display error information indicating the occurrence of an error. An air conditioning device according to claim 1 or claim 2.

7. An air conditioning system having multiple indoor units that are connected to each other in a way that allows them to communicate with one another and are configured as a group, A safety device that takes safety measures when a refrigerant sensor detects a refrigerant leak, A terminal device having an operating mechanism and a display mechanism, Equipped with, When the refrigerant sensor is located outside the multiple indoor units, Of the aforementioned multiple indoor units, the indoor unit designated as the master unit is: A transmitting unit that transmits an inspection signal to the refrigerant sensor to indicate the start of the inspection when inspecting the safety device, A receiving unit that receives a response signal from the refrigerant sensor indicating that the inspection signal has been received, When the receiving unit receives the response signal from the refrigerant sensor, the instruction unit causes the display mechanism of the terminal device to display that the multiple indoor units are in inspection status. Equipped with, The response signal indicates that the refrigerant sensor has been set to a pseudo-leakage state when the inspection signal is received, according to the air conditioning system.

8. The transmitting unit transmits the inspection signal to the refrigerant sensor. The receiving unit receives the response signal from the refrigerant sensor, The instruction unit, when the receiving unit receives the response signal from the refrigerant sensor, causes the display mechanism of the terminal device to display that the multiple indoor units are in inspection status. The air conditioning device according to claim 7.

9. The instruction unit drives the equipment constituting the safety device when the receiving unit receives the response signal from the refrigerant sensor. The air conditioning device according to claim 7 or claim 8.

10. The operating mechanism of the terminal device receives an inspection start operation, which is an operation to start the inspection of the safety device, and an inspection end operation, which is an operation to end the inspection of the safety device. If the inspection termination operation is performed between the time the inspection start operation is received and the time the receiving unit receives the response signal from the refrigerant sensor, the inspection termination operation will not be accepted. The air conditioning device according to claim 7 or claim 8.

11. The instruction unit, if the receiving unit does not receive the response signal from the refrigerant sensor within a predetermined period from the time the transmitting unit transmits the inspection signal, causes the display mechanism of the terminal device to display error information indicating the occurrence of an error. The air conditioning device according to claim 7 or claim 8.

12. Multiple indoor units that are connected to each other and configured as a group, A safety device that takes safety measures when a refrigerant sensor detects a refrigerant leak, A terminal device having an operating mechanism and a display mechanism, A control method for an air conditioning system, comprising: When the refrigerant sensor is located inside each of the multiple indoor units, Of the multiple indoor units mentioned above, the indoor unit designated as the master unit shall, when inspecting the safety device, A transmission step of transmitting an inspection signal to all other indoor units and the refrigerant sensor among the multiple indoor units, indicating that an inspection should be started. A receiving step in which a response signal indicating that the inspection signal has been received is received from all the other indoor units and the refrigerant sensor, In the receiving step, when the response signals are received from all the other indoor units and the refrigerant sensor, an instruction step is given to cause the display mechanism of the terminal device to display that the multiple indoor units are in inspection status. Execute, A control method for an air conditioning system, wherein the response signal indicates that the refrigerant sensor has been set to a pseudo-leakage state when the inspection signal is received.

13. Multiple indoor units that are connected to each other and configured as a group, A safety device that takes safety measures when a refrigerant sensor detects a refrigerant leak, A terminal device having an operating mechanism and a display mechanism, A control method for an air conditioning system, comprising: When the refrigerant sensor is located outside the multiple indoor units, Of the multiple indoor units mentioned above, the indoor unit designated as the master unit shall, when inspecting the safety device, A transmission step of transmitting an inspection signal to the refrigerant sensor to indicate that inspection should be started, A receiving step of receiving a response signal from the refrigerant sensor indicating that the inspection signal has been received, In the receiving step, when the response signal is received from the refrigerant sensor, an instruction step is given to cause the display mechanism of the terminal device to display that the multiple indoor units are in inspection status, Execute, A control method for an air conditioning system, wherein the response signal indicates that the refrigerant sensor has been set to a pseudo-leakage state when the inspection signal is received.

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