Air conditioning system

Abstract

This invention provides an air conditioning system that can suppress malfunctions caused by communication between air conditioners belonging to different refrigerant systems. [Solution] An air conditioning system 1 comprises an outdoor unit 10a, an indoor unit 20a, an outdoor unit 10b, and an indoor unit 20b, wherein the outdoor unit 10a and the indoor unit 20a belong to refrigerant system A, and the outdoor unit 10b and the indoor unit 20b belong to refrigerant system B, and each air conditioner has system information which is information about the refrigerant system to which it belongs, and each air conditioner can transmit predetermined information to other air conditioners via a communication network based on the system information it possesses, and when an air conditioner receives predetermined information from an air conditioner belonging to the system information it possesses, it performs processing according to the predetermined information, and when an air conditioner receives predetermined information from an air conditioner belonging to a refrigerant system different from the system information it possesses, it does not perform processing according to the predetermined information.

Description

Technical Field

[0001] The present invention relates to an air conditioning system.

Background Art

[0002] Conventionally, in an air conditioning system having a plurality of air conditioners such as an outdoor unit and an indoor unit, for example, like the air conditioning system described in Patent Document 1 (Japanese Patent Laid-Open No. 07-071809), identification information such as an address unique to each air conditioner is allocated, and information processing is performed based on the identification information, whereby an air conditioning system that manages and controls each air conditioner via a communication network has been proposed.

Summary of the Invention

Problems to be Solved by the Invention

[0003] As such an air conditioning system, there is a system provided with a plurality of refrigerant systems in which a plurality of refrigerant circuits through which a refrigerant circulates exist independently.

[0004] In such an air conditioning system provided with a plurality of refrigerant systems, for each refrigerant system, an outdoor unit and an indoor unit connected to each other by a refrigerant pipe are provided. In this air conditioning system, for each refrigerant system, control of the refrigerant to be circulated is performed by controlling the constituent devices of the outdoor unit and the indoor unit.

[0005] In such an air conditioning system provided with a plurality of refrigerant systems, for each refrigerant system, a self-system recognition process for the outdoor unit and the indoor unit to recognize the refrigerant system to which they belong is performed. Thereby, the outdoor unit can control each constituent device after grasping the attribute information such as the model, horsepower, and capacity of the indoor units belonging to its own refrigerant system.

[0006] In this self-system recognition process, one or more indoor units belonging to a particular refrigerant system send a registration request for their own information to the outdoor units belonging to that refrigerant system. The outdoor unit that receives this registration request from the indoor unit stores the information of the indoor unit and sends a response to the indoor unit. The indoor unit that receives the response from the outdoor unit stores the information of the outdoor unit. Through the above communication process, information about the equipment that constitutes the refrigerant system to which it belongs is obtained.

[0007] In this self-system recognition process, for example, if the outdoor unit does not know the number of indoor units belonging to its own refrigerant system, it can continue receiving registration requests from indoor units for a while, and when predetermined recognition conditions are met, such as a predetermined waiting time, it can consider that it has finished receiving registration requests from all indoor units belonging to its own refrigerant system. In this case, before the predetermined recognition conditions are met, the outdoor unit is in a state where it does not know the indoor units belonging to its own refrigerant system. On the other hand, the indoor unit already knows the outdoor units belonging to its own refrigerant system when it receives a response from the outdoor unit. Thus, although not limited to this example, there may be a time lag between when the indoor unit has completed its recognition and when the outdoor unit has completed its recognition, resulting in a period of time when there is a discrepancy in the recognition of its own refrigerant system between the outdoor unit and the indoor unit.

[0008] In an air conditioning system where such discrepancies in recognition can occur, for example, if an error in the piping connection between the outdoor and indoor units in the refrigerant system is corrected, the outdoor unit may remain in the state of recognizing its own refrigerant system before the change, while the indoor unit may be in the state of recognizing its own refrigerant system after the change. This could lead to the outdoor unit sending control commands to indoor units that do not belong to its own refrigerant system. [Means for solving the problem]

[0009] The air conditioning system relating to the first aspect comprises a first outdoor unit, a first indoor unit, a second outdoor unit, and a second indoor unit. The first outdoor unit and the first indoor unit belong to a first refrigerant system in which a refrigeration cycle is performed by the circulation of a first refrigerant. The second outdoor unit and the second indoor unit belong to a second refrigerant system in which a refrigeration cycle is performed by the circulation of a second refrigerant. The first outdoor unit, the first indoor unit, the second outdoor unit, and the second indoor unit are all air conditioners. The first refrigerant system and the second refrigerant system are both refrigerant systems. An air conditioner has system information, which is information about the refrigerant system to which it belongs. An air conditioner can transmit predetermined information to other air conditioners via a communication network based on the system information it possesses. When an air conditioner receives predetermined information from an air conditioner belonging to the system information it possesses, it performs processing according to the predetermined information. When an air conditioner receives predetermined information from an air conditioner belonging to a refrigerant system different from the system information it possesses, it does not perform processing according to the predetermined information.

[0010] In this air conditioning system, when an air conditioner receives predetermined information from another air conditioner, it determines whether or not that information comes from an air conditioner belonging to a different refrigerant system than its own. Therefore, even if it receives predetermined information transmitted from an air conditioner belonging to a refrigerant system other than its own, it is possible to suppress the occurrence of malfunctions that would result from processing according to that predetermined information.

[0011] In the air conditioning system relating to the second perspective, the air conditioner performs self-system recognition processing to identify the refrigerant system to which it belongs, as in the air conditioning system relating to the first perspective. The first outdoor unit and the second outdoor unit are outdoor units. The first indoor unit and the second indoor unit are indoor units. The conditions for the outdoor unit to complete self-system recognition processing and the conditions for the indoor unit to complete self-system recognition processing are different.

[0012] In this air conditioning system, even if there is a discrepancy in system recognition between the outdoor and indoor units due to different conditions for the outdoor unit to complete its self-system recognition process, it is possible to suppress the occurrence of malfunctions that result from processing according to predetermined information transmitted from air conditioners belonging to refrigerant systems other than its own.

[0013] In the air conditioning system relating to the third perspective, in the air conditioning system relating to the second perspective, during the self-system recognition process, the indoor unit sends a system recognition request to the outdoor unit of the refrigerant system to which it belongs. The outdoor unit that receives the system recognition request sends a system recognition response to the indoor unit that sent the system recognition request. The condition for the outdoor unit to complete the self-system recognition process is that a predetermined time has elapsed since the start of the self-system recognition process. The condition for the indoor unit to complete the self-system recognition process is that it receives a system recognition response.

[0014] In this air conditioning system, even if a discrepancy in system recognition occurs between the indoor and outdoor units after the indoor unit receives a system recognition response from the outdoor unit and before a predetermined time has elapsed since the outdoor unit started its own system recognition process, it is possible to suppress the occurrence of malfunctions that result from processing according to predetermined information transmitted from an air conditioner belonging to a refrigerant system other than its own.

[0015] In the air conditioning system relating to the fourth perspective, when the self-system recognition process is re-executed in the air conditioning system relating to the third perspective, the outdoor unit communicates with the indoor unit that it recognizes as belonging to its own refrigerant system regarding the control of the state of the refrigeration cycle in the refrigerant system to which it belongs, even before the re-execution of the self-system recognition process is completed.

[0016] In this air conditioning system, by performing self-system recognition processing again and communicating regarding the control of the refrigeration cycle state, if the indoor unit belonging to the refrigerant system to which the outdoor unit belongs has not been changed, it becomes possible to perform control targeting the intended indoor unit while performing self-system recognition processing again.

[0017] The air conditioning system according to the fifth aspect is the air conditioning system according to the fourth aspect. When the outdoor unit satisfies the condition for completing the self-system recognition process, it sets the recognition state of the indoor units belonging to the refrigerant system to which it belongs as the latest recognition state. Then, it communicates with the indoor units that it recognizes as belonging to the refrigerant system to which it belongs according to the latest recognition state regarding the control of the state of the refrigeration cycle in the refrigerant system to which it belongs.

[0018] In this air conditioning system, after the outdoor unit satisfies the condition for completing the self-system recognition process, it can control the indoor units belonging to the refrigerant system to which it belongs without any discrepancy in system recognition.

[0019] The air conditioning system according to the sixth aspect is the air conditioning system according to any one of the first to fifth aspects. The predetermined information includes identification information for identifying the air conditioner that is the source of the predetermined information.

[0020] In this air conditioning system, it becomes possible to determine whether the predetermined information has been transmitted from the air conditioners belonging to its refrigerant system based on the identification information for identifying the air conditioners.

Brief Description of the Drawings

[0021] [Figure 1] It is a schematic configuration diagram of the air conditioning system. [Figure 2] It is a connection configuration diagram regarding the refrigerant system of the air conditioning system. [Figure 3] It is a connection configuration diagram regarding the communication of the air conditioning system. [Figure 4] It is a flowchart of the self-system recognition process. [Figure 5] It is a flowchart of the transfer process of the self-system list. [Figure 6] It is a flowchart of the self-system recognition process when wiring replacement occurs. [[ID=​​​​​

[0022] Hereinafter, the air-conditioning system 1 according to an embodiment of the air-conditioning system will be described by taking it as an example.

[0023] (1) Outline of the air-conditioning system 1 FIG. 1 shows the electrical connection relationship of a plurality of air-conditioners (outdoor unit, indoor unit). FIG. 2 shows the connection relationship regarding the refrigerant circulation of a plurality of air-conditioners (outdoor unit, indoor unit). FIG. 3 shows the functional block configuration diagram in the air-conditioning system 1.

[0024] The air-conditioning system 1 is configured to include a plurality of refrigerant systems A and B. Each of the refrigerant systems A and B includes a plurality of air-conditioners.

[0025] The refrigerant system A includes an outdoor unit 10a and an indoor unit 20a which are air-conditioners, and refrigerant circulates between them. The refrigerant system B includes an outdoor unit 10b and an indoor unit 20b which are air-conditioners, and refrigerant circulates between them.

[0026] The outdoor unit 10a and the indoor unit 20a belonging to the refrigerant system A are electrically connected in a bus-type wiring form so as to be communicable via a transmission line (shown by a dotted line) within the system of the refrigerant system A. The outdoor unit 10b and the indoor unit 20b belonging to the refrigerant system B are electrically connected in a bus-type wiring form so as to be communicable via a transmission line (shown by a dotted line) within the system of the refrigerant system B.

[0027] The air-conditioners belonging to each of the refrigerant systems A and B are electrically connected so as to be communicable via a transmission line (shown by a dotted line) outside the system. In this embodiment, the outdoor unit 10a belonging to the refrigerant system A and the outdoor unit 10b belonging to the refrigerant system B are connected in a bus-type wiring form via a transmission line (shown by a dotted line) outside the system.

[0028] Also, the outdoor unit 10a, the indoor unit 20a, the outdoor unit 10b, and the indoor unit 20b are all connected to the same distribution board 7 via power lines, and the power supply is common.

[0029] As a communication system, the air conditioning system 1 is a communication system in which one specific unit among several air conditioners functions as the master air conditioner, and the remaining air conditioners function as slave air conditioners. In this embodiment of the air conditioning system 1, the outdoor unit 10a functions as the master air conditioner, and the indoor units 20a, 10b, and 20b are predetermined to function as slave air conditioners, so that the outdoor unit 10a, which is the master air conditioner, can manage and control each of the slave air conditioners. The outdoor unit 10b, which is a slave air conditioner, manages and controls the indoor units 20b of the refrigerant system to which it belongs based on commands from the outdoor unit 10a, which is the master air conditioner.

[0030] Furthermore, the communication network of the air conditioning system 1 in this embodiment is configured such that devices connected via physically existing transmission lines can communicate using low-frequency signals while suppressing crosstalk, and that devices not connected via physically existing transmission lines can communicate using high-frequency signals by generating crosstalk through inductive coupling or the like between transmission lines located at close range. Hereafter, unless otherwise explicitly stated that low-frequency signals are used, communication in the communication network will be conducted using high-frequency signals. Note that the transmission lines in this embodiment are not particularly limited, and for example, power lines or the like may be used as transmission lines.

[0031] Furthermore, in the air conditioning system 1, outdoor unit 10a, which is also the master air conditioner in the communication system, is predetermined to function as the system master outdoor unit that performs the overall processing of refrigerant system A to which it belongs, and outdoor unit 10b, which is a slave air conditioner in the communication system, is predetermined to function as the system master outdoor unit that performs the overall processing of refrigerant system B to which it belongs. Each air conditioner in the air conditioning system 1 may be configured to determine whether or not it is the system master outdoor unit based on information pre-stored in the memory of the microcontroller, such as the ROM described later, that the air conditioner has. Here, for example, if multiple outdoor units are connected to one refrigerant system, one of those multiple outdoor units will function as the system master outdoor unit.

[0032] (2) Overview of the refrigerant circuit Each refrigerant system A and B has refrigerant circuits 2a and 2b, respectively, which are composed of refrigerant equipment connected to the refrigerant equipment belonging to that system. Although the refrigerant systems are connected to each other via transmission lines outside the systems, these refrigerant circuits 2a and 2b for each refrigerant system are physically independent of each other, and refrigerant does not flow between refrigerant systems. Equipment belonging to each system will be given a lowercase subscript corresponding to the system name. Furthermore, the description of equipment belonging to refrigerant system B other than refrigerant system A will be omitted as it can be understood as a description of equipment corresponding to refrigerant system A.

[0033] Refrigerant system A includes an outdoor unit 10a, an indoor unit 20a, liquid refrigerant connecting pipe 4a, gas refrigerant connecting pipe 3a, and an air conditioning controller 8a that controls various operations in refrigerant system A.

[0034] Refrigerant system A harmonizes the air in the target space where the indoor unit 20a is installed by performing a vapor compression type refrigeration cycle within refrigerant system A.

[0035] (2-1) Outdoor unit The outdoor unit 10a is connected to the indoor unit 20a via liquid refrigerant connecting pipe 4a and gas refrigerant connecting pipe 3a, and constitutes part of the refrigerant circuit 2a of refrigerant system A. The outdoor unit 10a mainly includes a compressor 11a, a four-way switching valve 12a, an outdoor heat exchanger 13a, an outdoor expansion valve 16a, a low-pressure receiver 14a, an outdoor fan 15a, an outdoor controller 17a, etc.

[0036] The compressor 11a is a device that compresses the low-pressure refrigerant in the refrigeration cycle of refrigerant system A until it reaches high pressure. In this embodiment, a compressor 11a with variable capacity is used, which is controlled by the operating frequency.

[0037] The four-way switching valve 12a can switch between two states by switching the connection state in the refrigerant circuit 2a: one in which the discharge side of the compressor 11a is connected to the outdoor heat exchanger 13a while the suction side of the compressor 11a is connected to the gas refrigerant connecting pipe 3a via the low-pressure receiver 14a (see solid line in Figure 2); and another in which the discharge side of the compressor 11a is connected to the gas refrigerant connecting pipe 3a while the suction side of the compressor 11a is connected to the outdoor heat exchanger 13a via the low-pressure receiver 14a (see dotted line in Figure 2).

[0038] The outdoor heat exchanger 13a is a heat exchanger that functions as a condenser or radiator for high-pressure refrigerant in the refrigeration cycle of refrigerant system A during cooling operation, and as an evaporator for low-pressure refrigerant in the refrigeration cycle of refrigerant system A during heating operation.

[0039] The outdoor fan 15a supplies outdoor air into the outdoor unit 10a to the outdoor heat exchanger 13a, where it exchanges heat with the refrigerant, and then generates an airflow to discharge the air to the outside of the outdoor unit 10a. The outdoor fan 15a is rotationally driven by an outdoor fan motor.

[0040] The outdoor expansion valve 16a is installed between the liquid-side end of the outdoor heat exchanger 13a and the liquid refrigerant connecting pipe 4a. The valve opening of the outdoor expansion valve 16a can be adjusted, for example, by control.

[0041] The low-pressure receiver 14a is located between the suction side of the compressor 11a and one of the connection ports of the four-way switching valve 12a, and is a refrigerant container capable of storing excess refrigerant in the refrigerant circuit 2a as liquid refrigerant.

[0042] The outdoor controller 17a controls the operation of each component of the outdoor unit 10a. The outdoor controller 17a has multiple communication ports. The outdoor controller 17a is connected to the indoor controller 25a via a transmission line extending from one of the communication ports. The outdoor controller 17a is also connected to the outdoor controller 17b via a transmission line extending from another communication port. As shown in Figure 3, the outdoor controller 17a includes an outdoor communicator 31a and an outdoor microcontroller 36a.

[0043] The outdoor communication device 31a is a device for enabling communication between the outdoor controller 17a and other devices. It transmits information sent from the outdoor microcontroller 36a to other devices via the communication network, and receives information sent from other devices to the outdoor microcontroller 36a via the communication network. The outdoor communication device 31a has a processor 32a, ROM 33a, RAM 34a, and HPS 35a. The processor 32a is composed of, for example, a CPU (Central Processing Unit) and an MPU (Micro Processing Unit). The ROM 33a is a read-only memory and stores programs that are read and executed by the processor 32a to perform various communication processing, data for those programs, an ID which is unique identification information for the air conditioner obtained from the outdoor microcontroller 36a, and a system list which is a list of identification information for each air conditioner belonging to its own refrigerant system. Since the outdoor communication device 31a belongs to the outdoor unit 10a, which is the master air conditioner, its ROM 33a stores network configuration information, including the IDs of each air conditioner authorized to participate in the communication network of the air conditioning system 1. RAM 34a is Random Access Memory and functions as primary storage memory and working memory. HPS 35a is a high-pass filter that allows high-frequency signals to pass through and low-frequency signals to pass through among the communication signals it receives. The outdoor unit 10a is aware in advance that it is the master air conditioner by methods such as storing information in the ROM 38a of the outdoor microcontroller 36a, storing information in the ROM 33a of the outdoor communication device 31a, or confirming that its own address is the smallest when it is predetermined that the outdoor unit with the smallest address will be the master air conditioner. For this reason, the outdoor microcontroller 36a and the outdoor communication device 31a perform the various communication processes described later as the master air conditioner.

[0044] The outdoor microcontroller 36a is a device that performs information processing as the master air conditioner of the air conditioning system 1, controls the components of the outdoor unit 10a, and issues control instructions to the indoor controller 25a. It has a processor 37a, a ROM 38a, and a RAM 39a. The processor 37a is composed of, for example, a CPU, an MPU, etc. The ROM 38a stores programs that are read and executed by the processor 37a for various air conditioning controls and instruction creation, data for those programs, an ID which is unique identification information for the air conditioner, and information such as a self-system list which identifies each air conditioner belonging to its own refrigerant system by ID, etc., obtained from the outdoor communication device 31a. The ID of each air conditioner is determined to correspond to the unique manufacturing number of each air conditioner and does not overlap between air conditioners. The RAM 39a functions as primary storage memory and working memory. Furthermore, the outdoor microcomputer 36a controls the components of the outdoor unit 10a by starting and stopping the compressor 11a, controlling the operating frequency, switching the four-way switching valve 12a, controlling the airflow of the outdoor fan 15a, and controlling the valve opening of the outdoor expansion valve 16a, according to the set temperature information and operating mode information from the remote control 24a of the refrigerant system A.

[0045] Outdoor unit 10b differs from outdoor unit 10a, which is the master air conditioner, in that it functions as a slave air conditioner, but its general configuration is the same as that of outdoor unit 10a, and is indicated by the subscript b. Outdoor unit 10b is aware in advance that it is a slave air conditioner by methods such as storing information in the ROM 38b of the outdoor microcontroller 36b, storing information in the ROM 33b of the outdoor communication device 31b, or confirming that its own address is not the smallest when it is predetermined that the outdoor unit with the smallest address will be the master air conditioner. For this reason, the outdoor microcontroller 36b and the outdoor communication device 31b perform various communication processes as a slave air conditioner, as described later.

[0046] The outdoor controller 17b also has multiple communication ports, and is connected to the outdoor controller 17a via a transmission line extending from one communication port, and to the indoor controller 25b via a transmission line extending from another communication port. Since HPS35b is provided between the multiple communication ports of the outdoor controller 17b, the outdoor controller 17a and the indoor controller 25b can exchange signals using high-frequency communication, but the outdoor controller 17a and the indoor controller 25b cannot communicate using low-frequency signals.

[0047] (2-2) Indoor unit The indoor unit 20a is installed on the walls or ceiling of the room that is the target space. The indoor unit 20a is connected to the outdoor unit 10a via liquid refrigerant connecting pipe 4a and gas refrigerant connecting pipe 3a, and constitutes part of the refrigerant circuit 2a of refrigerant system A.

[0048] The indoor unit 20a includes an indoor heat exchanger 21a, an indoor fan 22a, an indoor expansion valve 26a, an indoor temperature sensor 23a, a remote control 24a, and an indoor controller 25a.

[0049] The indoor heat exchanger 21a is connected to the liquid refrigerant connecting pipe 4a on its liquid side and to the gas refrigerant connecting pipe 3a on its gas side. The indoor heat exchanger 21a functions as an evaporator for the low-pressure refrigerant in the refrigeration cycle during cooling operation and as a condenser or heat exchanger for the high-pressure refrigerant in the refrigeration cycle during heating operation.

[0050] The indoor fan 22a draws in indoor air, which is the space to be air-conditioned, into the indoor unit 20a, exchanges heat with the refrigerant in the indoor heat exchanger 21a, and then generates an airflow to discharge the air to the outside of the indoor unit 20a. The indoor fan 22a is rotationally driven by an indoor fan motor.

[0051] The indoor expansion valve 26a is installed between the liquid-side end of the indoor heat exchanger 21a and the liquid refrigerant connecting pipe 4a. The opening degree of the indoor expansion valve 26a can be adjusted, for example, by control.

[0052] The indoor temperature sensor 23a detects the temperature of the space targeted by the indoor unit 20a and transmits this information to the indoor controller 25a.

[0053] The remote control 24a is operated by the user and receives information such as the set temperature and the selection of an operating mode, such as cooling or heating, and transmits it to the indoor controller 25a.

[0054] As shown in Figure 3, the indoor controller 25a includes an indoor communication device 41a and an indoor microcontroller 46a.

[0055] The indoor communication device 41a is a device for enabling communication between the indoor controller 25a and other devices. It transmits information sent from the indoor microcontroller 46a to other devices via the communication network, and receives information sent from other devices to the indoor microcontroller 46a via the communication network. The indoor communication device 41a has a processor 42a, a ROM 43a, and a RAM 44a. The processor 42a is composed of, for example, a CPU, MPU, etc. The ROM 43a stores programs that are read and executed by the processor 42a for various communication processing, data for those programs, an ID which is unique identification information for the air conditioner obtained from the indoor microcontroller 46a, and a system list which is a list of identification information for each air conditioner belonging to its own refrigerant system. The RAM 44a functions as primary memory and working memory. The indoor unit 20a recognizes in advance that it is a slave air conditioner because information is stored in the ROM 43a of the indoor communication device 41a. Therefore, the indoor communication device 41a performs various communication processes as a sub-air conditioner, as described later.

[0056] The indoor microcontroller 46a is a device that controls the components of the indoor unit 20a and has a processor 47a, a ROM 48a, and a RAM 49a. The processor 47a is composed of, for example, a CPU, an MPU, etc. The ROM 48a stores programs that are read and executed by the processor 47a for various air conditioning controls, data for those programs, an ID which is unique identification information for the air conditioner, and information such as a self-system list which identifies each air conditioner belonging to its own refrigerant system by ID, etc., obtained from the indoor communication device 41a. The RAM 49a functions as primary memory and working memory. The indoor microcontroller 46a, for example, grasps the detected value of the indoor temperature sensor 23a of the indoor unit 20a belonging to refrigerant system A, and performs various controls such as valve opening control of the indoor expansion valve 26a and airflow control of the indoor fan 22a of the indoor unit 20a belonging to refrigerant system A, according to the set temperature information and operating mode information from the remote control 24a of the same refrigerant system.

[0057] The specific configuration of indoor unit 20b is the same as that of indoor unit 20a, and is indicated by the subscript b. Indoor unit 20b also recognizes in advance that it is a slave air conditioner, and indoor communication device 41b performs the various communication processes described later as a slave air conditioner.

[0058] (2-3) Air conditioning controller In refrigerant system A, the outdoor controller 17a and the indoor controller 25a are connected via a transmission line within the system to enable communication, thereby constituting the air conditioning controller 8a of refrigerant system A. The air conditioning controller 8a performs air conditioning control processing for each device in refrigerant system A, such as ensuring that the set temperature is met.

[0059] Similarly, in refrigerant system B, the outdoor controller 17b and the indoor controller 25b are connected via a transmission line within the system to enable communication, thereby constituting the air conditioning controller 8b for refrigerant system B. The air conditioning controller 8b performs air conditioning control processing for each device in refrigerant system B, such as ensuring that the set temperature is met.

[0060] (3) Air conditioning control processing As described above, the refrigeration cycles of refrigerant systems A and B in the air conditioning system 1 are independent of each other, and refrigerant system A can be controlled by air conditioning controller 8a, and refrigerant system B can be controlled by air conditioning controller 8b. The outdoor controller 17a of the outdoor unit 10a, which is the main air conditioning unit, can also perform coordinated control such as simultaneously starting or stopping refrigerant system A and refrigerant system B, and can also collect and manage information obtained from various sensors in refrigerant system A and refrigerant system B.

[0061] In the following explanation, we will use the cooling and heating modes performed in refrigerant system A as examples, but the same principles apply to other refrigerant systems B.

[0062] The air conditioning controller 8a, which consists of an outdoor controller 17a and an indoor controller 25a, selectively executes either a cooling operation mode or a heating operation mode based on instructions received from the remote control 24a or the like.

[0063] In cooling operation mode, the operating frequency of the compressor 11a is capacity-controlled, for example, so that the evaporation temperature of the refrigerant in the refrigerant circuit 2a reaches the target evaporation temperature. The gaseous refrigerant discharged from the compressor 11a condenses in the outdoor heat exchanger 13a via the four-way switching valve 12a. The refrigerant that has flowed through the outdoor heat exchanger 13a is depressurized as it passes through the outdoor expansion valve 16a, which has a controlled valve opening. The refrigerant that has been depressurized in the outdoor expansion valve 16a flows through the liquid refrigerant connecting pipe 4a and is sent to the indoor unit 20a. After that, the refrigerant is depressurized in the indoor expansion valve 26a, which has a controlled valve opening, evaporates in the indoor heat exchanger 21a, and then flows into the gaseous refrigerant connecting pipe 3a. The refrigerant that has flowed through the gaseous refrigerant connecting pipe 3a passes through the four-way switching valve 12a and the low-pressure receiver 14a, and is drawn back into the compressor 11a.

[0064] In heating operation mode, the operating frequency of the compressor 11a is capacity-controlled, for example, so that the condensation temperature of the refrigerant in the refrigerant circuit 2a reaches the target condensation temperature. The gaseous refrigerant discharged from the compressor 11a flows through the four-way switching valve 12a and the gaseous refrigerant connecting pipe 3a before being sent to the indoor unit 20a. Thereafter, the refrigerant condenses in the indoor heat exchanger 21a, is depressurized in the indoor expansion valve 26a with valve opening control, and then flows into the liquid refrigerant connecting pipe 4a. The refrigerant sent to the outdoor unit 10a via the liquid refrigerant connecting pipe 4a is depressurized in the outdoor expansion valve 16a and evaporates in the outdoor heat exchanger 13a. The refrigerant evaporated in the outdoor heat exchanger 13a passes through the four-way switching valve 12a and the low-pressure receiver 14a before being drawn back into the compressor 11a.

[0065] (4) Initial authentication process In air conditioning system 1, at the time of system installation, each air conditioner (outdoor unit 10a, indoor unit 20a, outdoor unit 10b, indoor unit 20b) is physically wired and connected to each other via transmission lines. An initial authentication process is performed when the system is first powered on. Each air conditioner is connected via transmission lines and powered on, but it does not know which air conditioner it is connected to. Therefore, triggered by the power being supplied to each air conditioner, an initial authentication process is performed when air conditioning system 1 is started up to authenticate the participation of each child air conditioner in the communication network of the parent air conditioner, outdoor unit 10a, and to determine the connection status of each air conditioner.

[0066] In the initial authentication process, outdoor units 10a and 10b, which are the main outdoor units of each refrigerant system, use known communication means (such as filter circuits and relays) that can reach only the air conditioners belonging to their respective refrigerant systems to notify each air conditioner belonging to their refrigerant system of their unique identification information, such as their address and ID, as a group ID. Specifically, the outdoor microcontroller 36a of outdoor unit 10a notifies the indoor microcontroller 46a of indoor unit 20a, which belongs to its refrigerant system A, of its identification information via the indoor communication device 41a, using the outdoor communication device 31a. The indoor microcontroller 46a stores the identification information of outdoor unit 10a, which indicates the refrigerant system (refrigerant system A) to which indoor unit 20a belongs, as a group ID in ROM 48a. Similarly, the outdoor microcontroller 36b of the outdoor unit 10b notifies the indoor microcontroller 46b of the indoor unit 20b, which belongs to its refrigerant system B, of its identification information as a group ID via the indoor communication device 31b. The indoor microcontroller 46b stores the identification information of the outdoor unit 10b, which indicates the refrigerant system (refrigerant system B) to which the indoor unit 20b belongs, as a group ID in the ROM 48b.

[0067] The initial authentication process is completed through the above steps. Once the initial authentication process is finished, the system recognition process begins.

[0068] (5) Self-system recognition processing Figure 4 shows a time chart of the self-system recognition process.

[0069] In the self-system recognition process, the system-main outdoor unit, which belongs to each refrigerant system, performs a process to identify the air conditioners belonging to its own refrigerant system, and the air conditioners other than the system-main unit, which belong to each refrigerant system, perform a process to identify the system-main outdoor unit in the refrigerant system to which it belongs.

[0070] Specifically, the self-system recognition process begins when the outdoor microcontroller 36a of the parent air conditioner (outdoor unit 10a) sends a self-system recognition trigger message via multicast using a high-frequency signal to inform each air conditioner that the self-system recognition process is starting. Here, the outdoor microcontroller 36a of the parent air conditioner (outdoor unit 10a) sends a self-system recognition trigger message via multicast to the indoor microcontroller 46a of the child air conditioner (indoor unit 20a), the outdoor microcontroller 36b of the child air conditioner (outdoor unit 10b), and the indoor microcontroller 46b of the child air conditioner (indoor unit 20b).

[0071] The outdoor microcontroller 36a of outdoor unit 10a, which is the parent air conditioner and the main outdoor unit of the system that sent the self-system recognition trigger message, and the outdoor microcontroller 36b of outdoor unit 10b, which is the main outdoor unit of the system that received the self-system recognition trigger message, start counting time from this point using a self-unit information reception waiting timer, which is a predetermined reception waiting time set in advance. This predetermined reception waiting time is a predetermined length of time that is specified in advance based on a predetermined upper limit value of the number of air conditioners that make up the refrigerant system.

[0072] Among the air conditioners that have received the self-system recognition trigger message, each air conditioner that is not the system's main outdoor unit sends a self-unit information registration request (system recognition request) to the system's main outdoor unit of the refrigerant system to which it belongs. Specifically, each air conditioner that is not the system's main outdoor unit can identify the system's main outdoor unit of the refrigerant system to which it belongs based on the group ID indicating the refrigerant system that it received and stored during the initial authentication process described above, and then send a self-unit information registration request to the system's main outdoor unit of the refrigerant system to which it belongs. Specifically, the indoor microcontroller 46a sends a self-unit information registration request to the outdoor microcontroller 36a, and the indoor microcontroller 46b sends a self-unit information registration request to the outdoor microcontroller 36b.

[0073] When the outdoor microcontroller 36a of the outdoor unit 10a, which is the main outdoor unit of the system, receives a self-unit information registration request, it adds the air conditioner that sent the self-unit information registration request to its own system list, which is a list of air conditioners belonging to its own refrigerant system, and sends a self-unit information registration response request (system recognition response) back to the air conditioner that sent the self-unit information registration request. Specifically, when the outdoor microcontroller 36a receives a self-unit information registration request from the indoor microcontroller 46a, it adds the indoor unit 20a equipped with the indoor microcontroller 46a to its own system list, and sends a self-unit information registration response request back to the indoor microcontroller 46a. Similarly, when the outdoor microcontroller 36b of the outdoor unit 10b, which is the main outdoor unit of the system, receives a self-unit information registration request, it adds the air conditioner that sent the self-unit information registration request to its own system list, which is a list of air conditioners belonging to its own refrigerant system, and sends a self-unit information registration response request back to the air conditioner that sent the self-unit information registration request. Specifically, when the outdoor microcontroller 36b receives a self-unit information registration request from the indoor microcontroller 46b, it adds the indoor unit 20b equipped with the indoor microcontroller 46b to its own system list, and sends a self-unit information registration response request back to the indoor microcontroller 46b.

[0074] When an air conditioner receives a reply to its own unit information registration response request, it recognizes the air conditioner that sent the request as the main outdoor unit of the refrigerant system to which it belongs. Specifically, the indoor microcontroller 46a sets and stores the outdoor microcontroller 36a, the source of the own unit information registration response request, as the main outdoor unit of the refrigerant system to which it belongs. Similarly, the indoor microcontroller 46b also sets and stores the outdoor microcontroller 36b, the source of the own unit information registration response request, as the main outdoor unit of the refrigerant system to which it belongs. As a result, the indoor units 20a and 20b, which are not the main outdoor units, complete their own system recognition and transition to a state where refrigerant control is possible.

[0075] When the outdoor microcontroller 36a of outdoor unit 10a, which is the main outdoor unit of the system, finishes counting the time set by the self-information reception waiting timer, which is a predetermined reception waiting time, it confirms the self-system list consisting of air conditioners that are the source of the self-information registration request received up to that point, and the self-system recognition for outdoor unit 10a, which is the main outdoor unit of the system, is completed. Specifically, the outdoor microcontroller 36a confirms the self-system list which includes the ID of outdoor unit 10a and the ID of indoor unit 20a as the IDs of air conditioners belonging to refrigerant system A. Similarly, when the outdoor microcontroller 36b of outdoor unit 10b, which is the main outdoor unit of the system, finishes counting the time set by the self-information reception waiting timer, which is a predetermined reception waiting time, it confirms the self-system list consisting of air conditioners that are the source of the self-information registration request received up to that point, and the self-system recognition for outdoor unit 10b, which is the main outdoor unit of the system, is completed. Specifically, the outdoor microcontroller 36b determines its own system list, which includes the ID of the outdoor unit 10b and the ID of the indoor unit 20b, as the IDs of the air conditioners belonging to refrigerant system B.

[0076] Note that Figure 5 only illustrates communication between the outdoor unit 10a, which is the main outdoor unit of refrigerant system A, and the indoor unit 20a, which is an air conditioner belonging to refrigerant system A.

[0077] Specifically, each microcontroller simultaneously performs two tasks: a system recognition task to identify the air conditioners belonging to its own refrigerant system, and a system refrigerant control task to control the refrigerant of the equipment belonging to its own refrigerant system.

[0078] First, the outdoor microcontroller 36a of the outdoor unit 10a transmits a self-system recognition trigger message via multicast as the master air conditioner. Then, the outdoor microcontroller 36a of the outdoor unit 10a starts the self-system recognition task as the main outdoor unit of refrigerant system A. At this point, the outdoor microcontroller 36a starts counting the self-information reception waiting timer.

[0079] Upon receiving the self-system recognition trigger message, the indoor microcontroller 46a of the indoor unit 20a sends a self-system information registration request to the outdoor microcontroller 36a of the outdoor unit 10a, which is the main outdoor unit of refrigerant system A to which it belongs, as part of the self-system recognition task.

[0080] In the system recognition task, the outdoor microcontroller 36a of the outdoor unit 10a, which is the main outdoor unit of the system, receives a self-unit information registration request sent from the indoor microcontroller 46a, and adds the indoor unit 20a, which is the source of the self-unit information registration request, to the self-system list, which is a list of air conditioners belonging to its own refrigerant system A. Then, in the system recognition task, the outdoor microcontroller 36a sends a self-unit information registration response request back to the indoor microcontroller 46a, which was the source of the self-unit information registration request.

[0081] Upon receiving a reply to the self-information registration response request, the indoor microcomputer 46a, in its self-system recognition task, sets and stores the outdoor unit 10a, which was the source of the self-information registration response request, as the main outdoor unit of refrigerant system A to which it belongs. At this point, the indoor microcomputer 46a completes self-system recognition and executes the self-system refrigerant control task based on the information of the completed self-system recognition.

[0082] However, at this point, the outdoor microcontroller 36a of the outdoor unit 10a has not yet reached the timeout for receiving its own unit information in the self-system recognition task. The outdoor microcontroller 36a continues to wait for a self-system information registration request to be sent from an air conditioner belonging to its own refrigerant system A. Therefore, self-system recognition by the outdoor microcontroller 36a is not yet complete, and it is unable to identify the air conditioners in refrigerant system A to which it belongs.

[0083] Subsequently, in the self-system recognition task, when the self-system information reception waiting timer has elapsed, the outdoor microcontroller 36a recognizes the air conditioners that have received self-system information registration requests up to that point as air conditioners belonging to its own refrigerant system A, completing the self-system recognition in the outdoor microcontroller 36a and completing the self-system list. At this point, the outdoor microcontroller 36a completes the self-system recognition and executes the self-system refrigerant control task based on the information of the completed self-system recognition.

[0084] Subsequently, the outdoor microcontroller 36a, in its own system refrigerant control task, performs initial communication with the air conditioners included in its own system list (in this case, the indoor microcontroller 46a) to exchange information such as model and capacity, and then initiates regular communication to perform refrigerant control of its own system.

[0085] Here, the outdoor microcontroller 36a and the indoor microcontroller 46a are aware of the connection destination of the refrigerant system A to which they belong in the self-system refrigerant control task, so they can communicate while confirming that they belong to the same refrigerant system. Specifically, the outdoor microcontroller 36a sends an initial communication signal to the indoor microcontroller 46a that includes identification information such as an address that identifies the outdoor microcontroller 36a or the ID of the outdoor unit 10a. The indoor microcontroller 46a confirms that the identification information contained in the initial signal received from the outdoor microcontroller 36a identifies the outdoor unit 10a or the outdoor microcontroller 36a, which is the main outdoor unit of the refrigerant system A to which it belongs, and after confirming that they match, it performs the initial communication.

[0086] Furthermore, after completing the process of self-system recognition, during the stage of performing routine communication in the self-system refrigerant control task, the indoor microcontroller of the indoor unit that receives a signal related to refrigerant control from the outdoor microcontroller of the main outdoor unit of the system checks whether the identification information contained in the signal from the outdoor microcontroller is identification information that identifies the main outdoor unit (outdoor unit or outdoor microcontroller) of the refrigerant system to which it belongs, and then performs control processing according to the received signal.

[0087] During initial communication, initial setup information such as the model, horsepower, and capacity of the connected air conditioners is exchanged for each refrigerant system.

[0088] In routine communication, communications are used to specifically control certain equipment, such as to achieve a set temperature.

[0089] (6) Processing of communications from outside the system after rewiring has been completed As described above, after the self-system recognition process is completed, the main outdoor unit and other air conditioners such as indoor units belonging to the same refrigerant system communicate with each other while confirming identification information such as the sender's ID to confirm that they belong to the same refrigerant system. No air conditioner such as an indoor unit will receive refrigerant control instructions from a main outdoor unit belonging to a different refrigerant system.

[0090] However, as shown in Figure 6, for example, in an air conditioning system 1 where the self-system recognition process has been completed and steady-state communication in the self-system refrigerant control task has started, if a miswiring is found and the wiring is reconnected to the correct wiring as originally intended, then in the self-system refrigerant control task, a situation may occur where a specific air conditioner temporarily receives refrigerant control instructions from the system's main outdoor unit belonging to a different refrigerant system. Specifically, the timing at which self-system recognition is completed in the outdoor microcontroller (when the self-information reception waiting timer has elapsed) and the timing at which self-system recognition is completed in the indoor microcontroller (when the system's main outdoor unit sends a reply request for self-information registration in response to the self-information registration request) are different. As a result, the outdoor microcontroller completes self-system recognition a little while after the indoor microcontroller completes self-system recognition, so in the self-system refrigerant control task, refrigerant control communication from a different refrigerant system may temporarily occur.

[0091] Figure 6 illustrates an example where, after connecting the outdoor unit 10a and the indoor unit 20b, and connecting the outdoor unit 10b and the indoor unit 20a, the initial authentication process and self-system recognition process are completed, initial communication is performed, and then, at the stage where regular communication regarding refrigerant control is performed, a miswiring is discovered due to reasons such as the combination of models or capacity not being as intended, and the indoor unit 20a is reconnected to the outdoor unit 10a, and the indoor unit 20b is reconnected to the outdoor unit 10b.

[0092] In this case, prior to the rewiring, the outdoor microcomputer 36a of the outdoor unit 10a recognizes that the indoor unit 20b belongs to its refrigerant system, and the indoor microcomputer 46b of the indoor unit 20b recognizes that the outdoor unit 10a is the main outdoor unit of its refrigerant system. Similarly, prior to the rewiring, the outdoor microcomputer 36b of the outdoor unit 10b recognizes that the indoor unit 20a belongs to its refrigerant system, and the indoor microcomputer 46a of the indoor unit 20a recognizes that the outdoor unit 10b is the main outdoor unit of its refrigerant system.

[0093] After the rewiring is completed, when the self-system recognition reset button (not shown) provided on the outdoor unit 10a, which is the master air conditioner of the air conditioning system 1, is pressed again, the outdoor unit that is the system master outdoor unit of each refrigerant system uses a known communication means (filter circuit, relay, etc.) that can reach only the air conditioners belonging to its refrigerant system to notify each air conditioner belonging to its refrigerant system of its unique identification information such as its address and ID as a group ID. Then, the outdoor microcontroller 36a of the outdoor unit 10a, which is the master air conditioner, multicasts a self-system recognition trigger message, and the self-system recognition process is performed again.

[0094] In this case, as described above, the outdoor microcontroller 36a of outdoor unit 10a and the outdoor microcontroller 36b of outdoor unit 10b each start counting their own unit information reception waiting timers in their own system recognition task.

[0095] Here, the outdoor microcontroller 36a of the outdoor unit 10a has not yet updated its self-system list, which it has grasped in the self-system recognition task. It continues to recognize the indoor microcontroller 46b of the indoor unit 20b as its own system, and the self-system list has not been updated in the self-system refrigerant control task either. Therefore, in the self-system refrigerant control task, the outdoor microcontroller 36a of the outdoor unit 10a periodically sends instructions for refrigerant control via steady communication to the indoor microcontroller 46b of the indoor unit 20b. Similarly, the indoor microcontroller 46b, which receives these instructions, has not updated the information of the main outdoor unit of its refrigerant system in either the self-system recognition task or the self-system refrigerant control task, and continues to recognize the outdoor unit 10a as the main outdoor unit of its refrigerant system. Therefore, in the self-system refrigerant control task, the indoor microcontroller 46b determines that the instruction is from the intended outdoor unit and executes refrigerant control via steady communication. The relationship between the outdoor microcontroller 36b of the outdoor unit 10b and the indoor microcontroller 46a of the indoor unit 20a is similar. Furthermore, by configuring the system so that steady-state communication proceeds simultaneously even when the self-system recognition process is performed again, if the air conditioning system 1 includes a refrigerant system that was not miswired, it is possible to control the refrigerant even before the self-system recognition process of the other refrigerant systems is completed, for the refrigerant system that does not require rewiring and is free from miswiring.

[0096] Subsequently, upon receiving the self-system recognition trigger message from the outdoor microcontroller 36a, the indoor microcontroller 46a of the indoor unit 20a sends a self-system information registration request to the outdoor microcontroller 36a of the outdoor unit 10a, which is the system's main outdoor unit for the refrigerant system to which it belongs.

[0097] When the outdoor microcontroller 36a of the outdoor unit 10a, which is the main outdoor unit of the system, receives a self-unit information registration request sent from the indoor microcontroller 46a during the self-system recognition task, it overwrites the self-system list, which is a list of air conditioners belonging to its own refrigerant system, with the indoor unit 20a that has the indoor microcontroller 46a that sent the self-unit information registration request. However, the self-system list remains in an undetermined state until the self-unit information reception waiting timer has elapsed.

[0098] On the other hand, in the self-system recognition task, the indoor microcontroller 46a receives a self-unit information registration response request from the outdoor microcontroller 36a, overwrites and stores the outdoor unit 10a, which is the source of the self-unit information registration response request, as the system master outdoor unit of the refrigerant system to which it belongs, thereby completing the self-system recognition task. Then, in the self-system refrigerant control task, the indoor microcontroller 46a of the indoor unit 20a starts self-system refrigerant control based on the updated self-system list.

[0099] However, at this point, in the outdoor unit 10a after rewiring, the timer for receiving the unit information, which the outdoor microcontroller 36a is counting during the self-system recognition task, has not yet elapsed. Therefore, the outdoor microcontroller 36a is still unable to perform the self-system refrigerant control task based on the updated and correct self-system list after rewiring. Consequently, at this point, the outdoor microcontroller 36a of the outdoor unit 10a is in a state where the self-system refrigerant control task is performed with the indoor unit 20b still registered in the self-system list. Similarly, at this point, the outdoor microcontroller 36b of the outdoor unit 10b is also in a state where the self-system refrigerant control task is performed with the indoor unit 20a still registered in the self-system list. Consequently, in the self-system refrigerant control task, the outdoor microcontroller 36b of the outdoor unit 10b sends a refrigerant control signal via steady-state communication to the indoor microcontroller 46a of the indoor unit 20a, which is still registered in the self-system list that has not yet been updated to the correct state. Note that in Figure 6, to avoid making the diagram too complex, the transmission of the self-information registration request from the indoor unit 20b has been omitted.

[0100] As described above, although communication occurs between air conditioners belonging to different refrigerant systems, in the self-system refrigerant control task, the indoor microcontroller 46a of the indoor unit 20a, which has received a refrigerant control signal from the outdoor microcontroller 36b of the outdoor unit 10b through normal communication, already recognizes that the correct main outdoor unit of the system after rewiring is the outdoor unit 10a. Therefore, it determines that the signal from the outdoor microcontroller 36b of the outdoor unit 10b is a signal from the microcontroller of an air conditioner outside the system, and is configured to ignore the signal received from the microcontroller of the air conditioner outside the system. This is because the communication between air conditioners belonging to different refrigerant systems is a temporary situation that occurs only during the remaining time until the self-information reception waiting timer expires, and will be resolved once that remaining time has elapsed. Therefore, instead of treating the occurrence of out-of-system communication as a problem and starting new processing to resolve the problem, the system is configured to ignore the signal and wait for the remaining time to expire. Therefore, even if the indoor microcontroller 46a of the indoor unit 20a receives a signal from the outdoor microcontroller 36b of the outdoor unit 10b via off-grid communication, it does not send any instructions to the outdoor microcontroller 36a of the outdoor unit 10a, which it recognizes as the main outdoor unit of the grid, such as to have it redo the initial communication. Ignoring a signal received from the microcontroller of an off-grid air conditioner means that while the microcontroller will perform confirmation processing based on identification information that the signal was sent from an off-grid microcontroller, it will not perform any specific instructions contained in the signal.

[0101] Then, in the self-system recognition task, the outdoor microcontroller 36a of the outdoor unit 10a updates the self-system list to a state where the indoor unit 20a is registered when the self-system information reception waiting timer has elapsed, and in the self-system refrigerant control task, it executes the self-system refrigerant control task based on the updated self-system list. After that, similarly to the above, in the self-system refrigerant control task, the outdoor microcontroller 36a of the outdoor unit 10a performs initial communication with the indoor microcontroller 46a of the indoor unit 20a based on the self-system list. At this stage, the system master outdoor unit known to the indoor microcontroller 46a of the indoor unit 20a is the same as the outdoor microcontroller 36a of the outdoor unit 10a, which is the source of the initial communication, so the initial communication is performed. Then, in the self-system refrigerant control task, the outdoor microcontroller 36a of the outdoor unit 10a starts refrigerant control by steady-state communication with the indoor microcontroller 46a of the indoor unit 20a. Similarly, after the rewiring has been completed and the timer for receiving the unit's own information has elapsed, the outdoor microcontroller 36b of the outdoor unit 10b initiates refrigerant control via steady-state communication with the indoor microcontroller 46b of the indoor unit 20b. The refrigerant control information (predetermined information) transmitted via steady-state communication includes control information such as the rotational speed of the compressor in the refrigerant circuit, the valve opening of the expansion valve, the airflow of the fan, and the connection status of the four-way switching valve.

[0102] (7) Features of the Embodiment In the air conditioning system 1 of this embodiment, in the process of self-system recognition, the timing at which the system's main outdoor unit determines its own system list and the timing at which an air conditioner such as an indoor unit determines the system's main outdoor unit of the refrigerant system to which it belongs are different. As a result, an air conditioner such as an indoor unit may receive a signal from a system's main outdoor unit that is outside its own system.

[0103] In contrast, in this embodiment, the air conditioner, such as the indoor unit, is configured to ignore signals even if it receives a signal from a main outdoor unit outside the grid. Therefore, it is possible to suppress malfunctions in the air conditioning system 1 that may occur when the air conditioner, such as the indoor unit, receives a signal from a main outdoor unit outside the grid and processes the signal according to its contents without ignoring it.

[0104] For example, consider the case shown in Figure 6 above, where the indoor microcontroller 46a of indoor unit 20a, upon receiving a signal from outdoor microcontroller 36b via off-grid communication, determines that the signal is not from the outdoor microcontroller 36a of outdoor unit 10a, which it recognizes as the grid-master outdoor unit. In this case, instead of ignoring the signal, it is configured to send an instruction to the outdoor microcontroller 36a of outdoor unit 10a, which it recognizes as the grid-master outdoor unit, to redo the initial communication. In this case, the outdoor microcontroller 36a of outdoor unit 10a, having received the instruction to redo the initial communication, sends a reply to the indoor microcontroller 46b of indoor unit 20b, because at that point, its registration in the local grid list has not yet been updated and remains that of indoor unit 20b. However, since the indoor microcontroller 46b of the indoor unit 20b already recognizes that the outdoor unit 10b is the main outdoor unit of its system, it sends an instruction to the outdoor microcontroller 36b of the outdoor unit 10b, which it recognizes as the main outdoor unit of its system, to redo the initial communication. In this way, because the timing of the completion of the self-system recognition process differs, countless unnecessary communications are generated, which may unnecessarily increase the load on the communication network. In contrast, according to this embodiment, the occurrence of such problems is suppressed because signals from the main outdoor unit of an unrelated system are simply ignored.

[0105] Furthermore, in this air conditioning system 1, when the self-system recognition process is performed again, even while the microcontroller of each air conditioner is communicating for system recognition, the microcontroller of each air conditioner performs steady-state communication based on the refrigerant system it recognizes to control the refrigerant in its own system. For example, if the air conditioning system 1 includes a refrigerant system that does not undergo rewiring, when the self-system recognition process is performed again, it is possible to continue refrigerant control through steady-state communication for the refrigerant system that does not undergo rewiring, even while the self-system recognition process is progressing in the refrigerant system that has undergone rewiring.

[0106] (8) Other embodiments (8-1) Other Embodiments A In the above embodiment, a specific example was described in which the indoor unit is configured to ignore a signal received from an outdoor unit outside the system's main power grid.

[0107] However, this is not limited to cases where signals from air conditioners outside the grid are ignored.

[0108] For example, in the refrigerant system B in the above embodiment, if there is an outdoor unit that is not the main outdoor unit of the refrigerant system B that is connected in parallel to outdoor unit 10b, which is the main outdoor unit of the refrigerant system B, then, similar to the above embodiment, the outdoor unit that is not the main outdoor unit may recognize that outdoor unit 10b is the main outdoor unit of the refrigerant system to which it belongs before outdoor unit 10b waits for the self-information reception waiting timer to elapse, resulting in a situation where the timing of confirmation of its own system is different. In this case, it is preferable that the outdoor unit that is not the main outdoor unit is configured to ignore signals from outdoor unit 10a, which is the main outdoor unit of the system outside of the system.

[0109] Furthermore, from the viewpoint of more efficiently suppressing malfunctions caused by off-grid communication such as communication load, it is preferable that the air conditioning system 1 is configured to ignore signals received by indoor units from off-grid main outdoor units, as well as signals received by outdoor units other than the main outdoor units from off-grid main outdoor units.

[0110] (8-2) Other Embodiments B In the above embodiment, the case in which the air conditioning system 1 is composed of an air conditioner including an outdoor unit and an indoor unit was described as an example.

[0111] In contrast, the air conditioning system 1 is not limited to this, and for example, an external device such as a central controller may be connected to enable communication with the air conditioner over a communication network.

[0112] In this case, it is preferable that each air conditioner is configured to process signals from external devices such as a central controller, even though these signals are considered signals from devices outside the system, rather than ignoring them.

[0113] (8-3) Other Embodiments C In the above embodiment of the air conditioning system 1, the case in which there are multiple refrigerant circuits, each consisting of an outdoor unit and an indoor unit connected by refrigerant piping, was described as an example.

[0114] In contrast, the air conditioning system may be an air conditioning system 101 that has multiple refrigerant circuits connected by refrigerant piping with a connecting unit interposed between the outdoor unit and the indoor unit. Such a refrigerant circuit is called a three-pipe type, etc.

[0115] Figure 7 shows a partial configuration of the air conditioning system 101, which has a refrigerant circuit 102a of such a single refrigerant system A'.

[0116] The air conditioning system 101 is a device used for heating and cooling indoor spaces such as buildings by operating a vapor compression type refrigeration cycle.

[0117] The air conditioning system 101 mainly comprises one outdoor unit 110a, multiple indoor units 120a, 220a, and 320a, connection units 190a, 290a, and 390a connected to each indoor unit 120a, 220a, and 320a, and liquid refrigerant connecting pipes 103a, low-pressure gas refrigerant connecting pipes 104a, and high-pressure gas refrigerant connecting pipes 105a that connect the outdoor unit 110a to the indoor units 120a, 220a, and 320a via the connection units 190a, 290a, and 390a. The air conditioning system 101 is configured to enable simultaneous cooling and heating operation according to the requirements of the indoor air-conditioned spaces in which the indoor units 120a, 220a, and 320a are installed, for example, by performing cooling operation in one air-conditioned space while performing heating operation in another air-conditioned space.

[0118] The indoor units 120a, 220a, and 320a are installed in the ceiling of buildings or other indoor spaces by being embedded or suspended, or by being wall-mounted on indoor walls. The indoor units 120a, 220a, and 320a are connected to the outdoor unit 110a via liquid refrigerant connecting pipe 103a, low-pressure gas refrigerant connecting pipe 104a, high-pressure gas refrigerant connecting pipe 105a, and connection units 190a, 290a, and 390a, and constitute part of the refrigerant circuit 102a.

[0119] Next, we will explain the configuration of indoor units 120a, 220a, and 320a. Since indoor units 120a and 220a / 320a have the same configuration, we will only explain the configuration of indoor unit 120a here, and omit the explanation of each part of indoor units 220a and 320a.

[0120] The indoor unit 120a constitutes part of the refrigerant circuit 102a and mainly comprises an indoor expansion valve 126a and an indoor heat exchanger 121a. In this embodiment, the indoor expansion valve 126a is a valve with an open-degree controllable opening that is connected to the liquid side of the indoor heat exchanger 121a in order to adjust the flow rate of the refrigerant flowing through the indoor unit 120a. In this embodiment, the indoor heat exchanger 121a is a device for exchanging heat between the refrigerant and indoor air. In this embodiment, the indoor unit 120a is equipped with a blower fan (not shown) for drawing in indoor air into the unit, exchanging heat with it, and supplying it indoors as supply air, and is capable of exchanging heat between the indoor air and the refrigerant flowing through the indoor heat exchanger 121a.

[0121] The indoor unit 120a is equipped with an indoor controller 125a that controls the operation of each part that constitutes the indoor unit 120a. The indoor controller 125a, like the indoor controller 25a in the above embodiment, is equipped with an indoor microcomputer (not shown) provided for controlling the indoor unit 120a and an indoor communicator (not shown) provided for controlling communication with other devices, and exchanges signals etc. between the outdoor controller 117a of the outdoor unit 110a and the connection controller 197a of the connection unit 190a. Similarly, the indoor controller 225a exchanges signals etc. between the outdoor controller 117a and the connection controller 297a, and the indoor controller 325a exchanges signals etc. between the outdoor controller 117a and the connection controller 397a.

[0122] The outdoor unit 110a is installed on the rooftop of a building or the like, and is connected to the indoor units 120a, 220a, and 320a via connection units 190a, 290a, and 390a, and liquid refrigerant connecting pipe 103a, low-pressure gas refrigerant connecting pipe 104a, and high-pressure gas refrigerant connecting pipe 105a, forming a refrigerant circuit 102a between the indoor units 120a, 220a, and 320a.

[0123] Next, the configuration of the outdoor unit 110a will be described. The outdoor unit 110a constitutes part of the refrigerant circuit 102a and mainly includes a compressor 111a, a four-way switching valve 112a, an outdoor heat exchanger 113a, a gas-liquid separator 114a, and a capillary tube 116a.

[0124] In this embodiment, the compressor 111a is a positive displacement compressor whose operating capacity can be varied by inverter control.

[0125] The outdoor heat exchanger 113a is a heat exchanger capable of functioning as both a refrigerant evaporator and a refrigerant condenser. The gas side of the outdoor heat exchanger 113a is connected to the four-way switching valve 112a, and the liquid side is connected to the liquid refrigerant connecting pipe 103a.

[0126] The capillary tube 116a connects the four-way switching valve 112a and the gas-liquid separator 114a.

[0127] The outdoor unit 110a is equipped with an outdoor controller 117a that controls the operation of each component of the outdoor unit 110a. The outdoor controller 117a, like the outdoor controller 17a in the above embodiment, is equipped with an outdoor microcomputer (not shown) provided for controlling the outdoor unit 110a and an outdoor communicator (not shown) provided for communication control with other devices, and exchanges signals etc. between the indoor controllers 125a, 225a, and 325a of the indoor units 120a, 220a, and 320a, and the connection controllers 197a, 297a, and 391a of the connection units 190a, 290a, and 390a.

[0128] The connection units 190a, 290a, and 390a are installed indoors in buildings, etc., together with the indoor units 120a, 220a, and 320a. The connection units 190a, 290a, and 390a, along with the liquid refrigerant connecting pipe 103a, the low-pressure gas refrigerant connecting pipe 104a, and the high-pressure gas refrigerant connecting pipe 105a, are interposed between the indoor units 120a, 220a, and 320a and the outdoor unit 110a, and constitute part of the refrigerant circuit 102a.

[0129] Next, we will explain the configurations of connection units 190a, 290a, and 390a. Since connection unit 190a and connection units 290a and 390a have similar configurations, we will only explain the configuration of connection unit 190a here, and omit the explanations of each part of connection units 290a and 390a.

[0130] The connection unit 190a constitutes part of the refrigerant circuit 102a and mainly includes a liquid connection pipe 191a, a low-pressure gas connection pipe 192a, a high-pressure gas connection pipe 193a, a combined gas connection pipe 194a, a high-pressure gas shut-off valve 195a, and a low-pressure gas shut-off valve 196a.

[0131] In this embodiment, the liquid connection pipe 191a connects the liquid refrigerant connecting pipe 103a to the indoor expansion valve 126a of the indoor unit 120a. The combined gas connection pipe 194a is connected to the gas side of the indoor heat exchanger 121a of the indoor unit 120a and combines the high-pressure gas connection pipe 193a, which is connected to the high-pressure gas refrigerant connecting pipe 105a, and the low-pressure gas connection pipe 192a, which is connected to the low-pressure gas refrigerant connecting pipe 104a. The high-pressure gas shut-off valve 195a is connected to the high-pressure gas connection pipe 193a and is a solenoid valve capable of controlling the flow and shut-off of refrigerant. The low-pressure gas shut-off valve 196a is connected to the low-pressure gas connection pipe 192a and is a solenoid valve capable of controlling the flow and shut-off of refrigerant.

[0132] As a result, when the indoor unit 120a is operating in cooling mode, the connection unit 190a is controlled to close the high-pressure gas shut-off valve 195a and open the low-pressure gas shut-off valve 196a. This causes the refrigerant flowing into the liquid connection pipe 191a through the liquid refrigerant connecting pipe 103a to be depressurized by the indoor expansion valve 126a of the indoor unit 120a, then evaporate in the indoor heat exchanger 121a, and flow back to the low-pressure gas refrigerant connecting pipe 104a through the combined gas connection pipe 194a and the low-pressure gas connection pipe 192a.

[0133] Furthermore, when the indoor unit 120a is operating in heating mode, the connection unit 190a is controlled to close the low-pressure gas shut-off valve 196a and open the high-pressure gas shut-off valve 195a. As a result, the refrigerant flowing through the high-pressure gas refrigerant connecting pipe 105a to the high-pressure gas connecting pipe 193a and the combined gas connecting pipe 194a is sent to the gas side of the indoor heat exchanger 121a of the indoor unit 120a, where it is condensed, depressurized by the indoor expansion valve 126a, and then flows back to the liquid refrigerant connecting pipe 103a through the liquid connecting pipe 191a.

[0134] Furthermore, the connection unit 190a is equipped with a connection controller 197a that controls the operation of each part constituting the connection unit 190a. The connection controller 197a corresponds to the indoor controller 25a in the above embodiment and is equipped with a connection microcontroller (not shown) provided for controlling the connection unit 190a and a connection communicator (not shown) provided for controlling communication with other devices, and exchanges signals etc. between the outdoor controller 117a of the outdoor unit 110a and the indoor controller 125a of the indoor unit 120a, etc. Similarly, the connection controller 297a exchanges signals etc. between the outdoor controller 117a and the indoor controller 225a, etc., and the connection controller 397a exchanges signals etc. between the outdoor controller 117a and the indoor controller 325a, etc.

[0135] As described above, the outdoor unit 110a, liquid refrigerant connecting pipe 103a, low-pressure gas refrigerant connecting pipe 104a, high-pressure gas refrigerant connecting pipe 105a, connection units 190a, 290a, 390a, and indoor units 120a, 220a, 320a are connected to form the refrigerant circuit 102a of the air conditioning system 101. In this embodiment of the air conditioning system 101, it is possible to perform so-called simultaneous cooling and heating operation, for example, when indoor units 120a and 220a perform cooling operation while indoor unit 320a performs heating operation.

[0136] (Note) While embodiments of this disclosure have been described above, it should be understood that various modifications to the form and details are possible without departing from the spirit and scope of this disclosure as described in the claims. [Explanation of Symbols]

[0137] 1: Air conditioning system 10a: Outdoor unit (1st outdoor unit) 10b: Outdoor unit (second outdoor unit) 17a: Outdoor controller 20a: Indoor unit (1st indoor unit) 20b: Indoor unit (2nd indoor unit) 31a: Outdoor communication device 31b: Outdoor communication device 33a: ROM 32a: Processor 41a: Indoor communication device 41b: Indoor communication device 101: Air conditioning system 110a: Outdoor unit (1st outdoor unit) 120a: Indoor unit (First indoor unit) 220a: Indoor unit (First indoor unit) 320a: Indoor unit (1st indoor unit) A: Refrigerant system (First refrigerant system) A': Refrigerant system B: Refrigerant system (second refrigerant system) [Prior art documents] [Patent Documents]

[0138] [Patent Document 1] Japanese Patent Application Publication No. 07-071809

Claims

1. The first outdoor unit (10a, 110a), The first indoor unit (20a, 120a, 220a, 320a) and, The second outdoor unit (10b) and The second indoor unit (20b), Equipped with, The first outdoor unit and the first indoor unit belong to the first refrigerant system (A) in which a refrigeration cycle is performed by the circulation of the first refrigerant. The second outdoor unit and the second indoor unit belong to the second refrigerant system (B), in which the refrigeration cycle is carried out by the circulation of the second refrigerant. The first outdoor unit, the first indoor unit, the second outdoor unit, and the second indoor unit are all air conditioners. The first refrigerant system and the second refrigerant system are both refrigerant systems. The aforementioned air conditioner has system information, which is information about the refrigerant system to which it belongs. The aforementioned air conditioner is capable of transmitting predetermined information to other air conditioners via a communication network based on the system information it possesses. When the air conditioner receives the predetermined information from an air conditioner belonging to the system information it possesses, it performs processing according to the predetermined information. If the aforementioned air conditioner receives the predetermined information from an air conditioner belonging to a refrigerant system different from the system information it possesses, it will not perform any processing according to the predetermined information. Air conditioning system (1, 101).

2. The aforementioned air conditioner performs self-system recognition processing to determine the refrigerant system to which it belongs. The first outdoor unit and the second outdoor unit are outdoor units, The first indoor unit and the second indoor unit are indoor units, The conditions under which the outdoor unit completes the self-system recognition process and the conditions under which the indoor unit completes the self-system recognition process are different. The air conditioning system according to claim 1.

3. In the self-system recognition process, the indoor unit sends a system recognition request to the outdoor unit of the refrigerant system to which it belongs, and the outdoor unit that receives the system recognition request sends a system recognition response to the indoor unit that sent the system recognition request. The condition for the outdoor unit to complete the self-system recognition process is that a predetermined time has elapsed since the start of the self-system recognition process. The condition for the indoor unit to complete the self-system recognition process is receiving the system recognition response. The air conditioning system according to claim 2.

4. When the aforementioned self-system recognition process is to be performed again, Even before the re-execution of the self-system recognition process is completed, the outdoor unit communicates with the indoor unit, which it recognizes as belonging to the refrigerant system to which it belongs, regarding the control of the state of the refrigeration cycle in the refrigerant system to which it belongs. The air conditioning system according to claim 3.

5. When the conditions for completing the self-system recognition process are met, the outdoor unit sets the recognition status of the indoor unit belonging to the refrigerant system to which it belongs as the latest recognition status, and then communicates with the indoor unit that it recognizes as belonging to the refrigerant system to which it belongs, in accordance with the latest recognition status, regarding the control of the state of the refrigeration cycle in the refrigerant system to which it belongs. The air conditioning system according to claim 4.

6. The predetermined information includes identification information that identifies the air conditioner that is the source of the predetermined information, An air conditioning system according to any one of claims 1 to 5.

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