Abstract:
A refrigerant system detection method for detecting refrigerant systems in an air conditioning system includes a drive step, an operation inhibition step and a recording step. The air conditioning system includes a plurality of indoor units having temperature sensors respectively connected to a plurality of outdoor units. The drive step puts the plurality of outdoor units into a driven state after a start-up time. The operation inhibition step stops or weakens the outdoor units one unit at a time after the drive step. The recording step correlates and records the outdoor units in which operation has been inhibited and the indoor units in which detection values of the temperature sensors have changed as a result of the outdoor units being inhibited. A refrigerant system detection system includes the connected indoor and outdoor units and a management component configured to perform the method. A storage component includes a program to perform the method.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This U.S. National stage application claims priority under 35 U.S.C. §119(a) to Japanese Patent Application No. 2007-177257, filed in Japan on Jul. 5, 2007, the entire contents of which are hereby incorporated herein by reference. 
     TECHNICAL FIELD 
     The present invention relates to a refrigerant system detection method, a refrigerant system detection system and a refrigerant system detection program that detect refrigerant systems resulting from outdoor units and indoor units. 
     BACKGROUND ART 
     Conventionally, there have been utilized air conditioning systems where plural outdoor units and plural indoor units are interconnected such that plural refrigerant systems are formed. In such air conditioning systems, an outdoor unit and the indoor units connected to that outdoor unit are regarded as belonging to the same refrigerant system, and air conditioning control is performed per refrigerant system. 
     Additionally, in the air conditioning system described in Japanese Patent Publication No. 2007-85673 below, there is proposed a method of causing the outdoor units to operate one unit at a time, identifying the indoor units whose state quantities change at that time, and detecting that that outdoor unit and those indoor units are in the same refrigerant system. 
     SUMMARY OF THE INVENTION 
     Technical Problem 
     However, in the air conditioning system described in Japanese Patent Publication No. 2007-85673, when there are plural refrigerant systems, there arises the need to cause operation of the outdoor units to start one unit at a time each time the air conditioning system detects each refrigerant system. For this reason, when start-up time becomes necessary when causing operation of the outdoor units to start, there arises the need to wait for the elapse of the start-up time each time the air conditioning system detects a refrigerant system. 
     The present invention has been made in light of the aforementioned point, and it is a problem of the present invention to provide a refrigerant system detection method, a refrigerant system detection system and a refrigerant system detection program that are capable of performing refrigerant system detection in a short amount of time. 
     Solution to the Problem 
     A refrigerant system detection method pertaining to a first aspect of the invention is a refrigerant system detection method that detects refrigerant systems in an air conditioning system comprising a plurality of indoor units having physical quantity sensors respectively and a plurality of outdoor units connected to the plurality of indoor units respectively, the refrigerant system detection method comprising a drive step, an operation inhibition step and a recording step. The drive step puts the plural outdoor units into a driven state after start-up time required for start-up. Here, “start-up time” means, for example, an amount of time required for start-up such as driving and stabilizing the outdoor units. The operation inhibition step inhibits operation by stopping or weakening the output of the outdoor units one unit at a time after the drive step. The recording step correlates and records the outdoor unit whose operation has been inhibited and the indoor units in which detection values of the physical quantity sensors have changed as a result of operation of that outdoor unit being inhibited. 
     Here, the refrigerant system detection method inhibits operation by stopping or weakening the output of the plural outdoor units in the driven state one unit at a time in order to identify the indoor units that are connected to the outdoor units and detect the refrigerant systems. Thus, the refrigerant system detection method can detect the indoor units that belong to the same refrigerant system as the outdoor unit whose operation has been inhibited by identifying the indoor units in which the detection values of the physical quantity sensors have changed in correspondence to the timing when operation of the outdoor unit has been inhibited. Moreover, the plural outdoor units are all placed in an operating state rather than being started one unit at a time, so the start-up times of the outdoor units can be allowed to advance at the same time. Additionally, it suffices simply to sequentially inhibit operation of the target outdoor unit each time the system of each outdoor unit is to be detected. For this reason, it becomes unnecessary to wait for the elapse of the start-up time of the outdoor unit each time the system of each outdoor unit is to be detected. 
     Thus, it becomes possible to shorten the amount of time required for refrigerant system detection. 
     A refrigerant system detection method pertaining to a second aspect of the invention is the refrigerant system detection method pertaining to the first aspect of the invention, wherein the physical quantity sensors are temperature sensors. 
     Here, by focusing on a change in temperature, it becomes possible to perform refrigerant system detection. 
     A refrigerant system detection method pertaining to a third aspect of the invention is the refrigerant system detection method pertaining to the second aspect of the invention, wherein the indoor units have indoor heat exchangers. Additionally, the temperature sensors detect temperature of refrigerant flowing through the indoor heat exchangers. 
     Here, by focusing on a change in the temperature of the refrigerant, it becomes possible to perform refrigerant system detection. 
     A refrigerant system detection method pertaining to a fourth aspect of the invention is the refrigerant system detection method pertaining to the second aspect of the invention, wherein the indoor units condition temperature of indoor air. Additionally, the temperature sensors detect temperature of conditioned air that is conditioned by the indoor units. 
     Here, by focusing on a change in the temperature of the conditioned air that is detected by the temperature sensors, it becomes possible to perform refrigerant system detection. 
     A refrigerant system detection method pertaining to a fifth aspect of the invention is the refrigerant system detection method pertaining to the third or fourth aspect of the invention, wherein the start-up time is an amount of time required from when operation of the outdoor units is started to until the temperature detected by the temperature sensors becomes constant. 
     Here, by placing the outdoor units in a driven state after the elapse of the start-up time and waiting until the detection values of the temperature sensors become stable, it becomes possible to more easily grasp the change in the detection values of the temperature sensors resulting from operation of the outdoor units being stopped thereafter. 
     Thus, it becomes possible to more definitely perform system detection. 
     A refrigerant system detection system pertaining to a sixth aspect of the invention comprises a plurality of indoor units, a plurality of outdoor units and a management component. The indoor units has a physical quantity sensor respectively. The outdoor units connected to the indoor units to configure refrigerant circuits. The management component puts the plural outdoor units into a driven state after start-up time required for start-up, thereafter performs operation inhibition control that stops or weakens the output of the outdoor units one unit at a time, and correlates and records the outdoor unit on which the operation inhibition control has been performed and the indoor units in which detection values of the physical quantity sensors have changed as a result of that outdoor unit being operation-inhibition-controlled. Here, “start-up time” means, for example, an amount of time required for start-up such as driving and stabilizing the outdoor units. 
     Here, the refrigerant system detection system inhibits operation by stopping or weakening the output of the plural outdoor units in the driven state one unit at a time in order to identify the indoor units that are connected to the outdoor units and detect the refrigerant systems. Thus, the refrigerant system detection system can detect the indoor units that belong to the same refrigerant system as the outdoor unit whose operation has been inhibited by identifying the indoor units in which the detection values of the physical quantity sensors have changed in correspondence to the timing when operation of the outdoor unit has been inhibited. Moreover, the plural outdoor units are all placed in an operating state rather than being started one unit at a time, so the start-up times of the outdoor units can be allowed to advance at the same time. Additionally, it suffices simply to sequentially inhibit operation of the target outdoor unit each time the system of each outdoor unit is to be detected. For this reason, it becomes unnecessary to wait for the elapse of the start-up time of the outdoor unit each time the system of each outdoor unit is to be detected. 
     Thus, it becomes possible to shorten the amount of time required for refrigerant system detection. 
     A refrigerant system detection program pertaining to a seventh aspect of the invention is a refrigerant system detection program detecting a refrigerant system in an air conditioning system comprising a plurality of indoor units having physical quantity sensors respectively connected to a plurality of outdoor units, the refrigerant system detection program comprising a drive step, an operation inhibition step and a recording step. In the drive step, a management component puts the plural outdoor units into a driven state after start-up time required for start-up. In the operation inhibition step, the management component stops or weakens the output of the outdoor units one unit at a time to inhibit operation after the drive step. In the recording step, the management component correlates and records the outdoor unit whose operation has been inhibited and the indoor units in which detection values of the physical quantity sensors have changed as a result of operation of that outdoor unit being inhibited. Here, “start-up time” means, for example, an amount of time required for start-up such as driving and stabilizing the outdoor units. 
     Here, the refrigerant system detection program inhibits operation by stopping or weakening the output of the plural outdoor units in the driven state one unit at a time in order to identify the indoor units that are connected to the outdoor units and detect the refrigerant systems. Thus, the refrigerant system detection program can detect the indoor units that belong to the same refrigerant system as the outdoor unit whose operation has been inhibited by identifying the indoor units in which the detection values of the physical quantity sensors have changed in correspondence to the timing when operation of the outdoor unit has been inhibited. Moreover, the plural outdoor units are all placed in an operating state rather than being started one unit at a time, so the start-up times of the outdoor units can be allowed to advance at the same time. Additionally, it suffices simply to sequentially inhibit operation of the target outdoor unit each time the system of each outdoor unit is to be detected. For this reason, it becomes unnecessary to wait for the elapse of the start-up time of the outdoor unit each time the system of each outdoor unit is to be detected. 
     Thus, it becomes possible to shorten the amount of time required for refrigerant system detection. 
     Advantageous Effects of the Invention 
     In the refrigerant system detection method of the first aspect of the invention, it becomes possible to shorten the amount of time required for refrigerant system detection. 
     In the refrigerant system detection method of the second aspect of the invention, by focusing on a change in temperature, it becomes possible to perform refrigerant system detection. 
     In the refrigerant system detection method of the third aspect of the invention, by focusing on a change in the temperature of the refrigerant, it becomes possible to perform refrigerant system detection. 
     In the refrigerant system detection method of the fourth aspect of the invention, by focusing on a change in the temperature of the conditioned air that is detected by the temperature sensors, it becomes possible to perform refrigerant system detection. 
     In the refrigerant system detection method of the fifth aspect of the invention, it becomes possible to more definitely perform system detection. 
     In the refrigerant system detection system of the sixth aspect of the invention, it becomes possible to shorten the amount of time required for refrigerant system detection. 
     In the refrigerant system detection program of the seventh aspect of the invention, it becomes possible to shorten the amount of time required for refrigerant system detection. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a system outline configuration diagram pertaining to an embodiment of the present invention. 
         FIG. 2  is a sequence diagram showing an outline of device information collection and delivery processing. 
         FIG. 3  is an outline flowchart of system setting. 
         FIG. 4  is a flowchart of IP address automatic assignment. 
         FIG. 5  is a flowchart of device information collection. 
         FIG. 6  is a flowchart of system detection processing. 
         FIG. 7  is a flowchart of indoor unit connection verification. 
         FIG. 8  is an explanatory diagram of a state where IP addresses have been automatically assigned. 
         FIG. 9  is an explanatory diagram of a state connected to a server in order to collect device information. 
         FIG. 10  is an explanatory diagram of system detection. 
         FIG. 11  is an explanatory diagram of indoor unit connection verification. 
         FIG. 12  is a system outline configuration diagram showing NAT traversal and router traversal. 
         FIG. 13  is an explanatory diagram of a device information table. 
         FIG. 14  is an explanatory diagram of information that each air conditioner holds. 
         FIG. 15  is an explanatory diagram for performing system detection processing. 
         FIG. 16  is a refrigerant circuit outline diagram showing the relationship between an outdoor unit and indoor units of one system. 
         FIG. 17  is an outline configuration diagram of each controller. 
         FIG. 18  is a diagram showing transitions of temperature changes resulting from stopping operation. 
         FIG. 19  is a diagram showing transitions of temperature changes in conventional refrigerant system detection. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     &lt;Outline Configuration of Air Conditioning System&gt; 
       FIG. 1  shows an outline configuration diagram of an air conditioning system  100  in which an embodiment of the present invention is employed. 
     The air conditioning system  100  is, as shown in  FIG. 1 , configured by a server  70 , routers  91  and  92  (routers R 1  and R 2 ), hubs  31 ,  32  and  33  (hubs H 1 , H 2  and H 3 ), outdoor units  50  and  60 , and indoor units  51 ,  52 ,  53 ,  61 ,  62  and  63 . 
     The server  70  is connected to the router  91  via the Internet IN, and communication using a global IP address is performed therebetween. 
     The router  91  is connected to the router  92  and the hub  31  via a network NW 1 . A firewall is disposed in this router  91  in order to prevent unauthorized access from the outside. In this router  91 , processing that converts a private IP address into a global IP address and processing such as converting IP addresses and port numbers when plural private IP addresses are shared by one global IP address are performed. 
     The outdoor unit  50  and the outdoor unit  60  are connected by Ethernet (registered trademark) to the hub  31 , and the outdoor units  50  and  60  belong to the network NW 1 . As a result of being mediated by the hub  31  in this manner, the router  91  and the outdoor units  50  and  60  can perform communication by private IP addresses. 
     The router  92  is connected to the hub  32  and the hub  33  via a network NW 2 . 
     The hub  32  is connected to the indoor units  51 ,  52  and  53  by Ethernet (registered trademark). The indoor units  51 ,  52  and  53  belong to the network NW 2 . As a result of being mediated by the hub  32  in this manner, the router  92  and the indoor units  51 ,  52  and  53  can perform communication by private IP addresses. 
     A central controller  40  and the indoor units  61 ,  62  and  63  are connected by Ethernet (registered trademark) to the hub  33 . The central controller  40  and the indoor units  61 ,  62  and  63  also belong to the network NW 2 . As a result of being mediated by the hub  33  in this manner, the router  92 , the indoor units  61 ,  62  and  63  and the central controller  40  can perform communication by private IP addresses. 
     The central controller  40  is, similar to an outdoor unit and an indoor unit, one part of an air conditioner is capable of various setting operations in regard to air conditioners in a local network. 
     The outdoor units  50  and  60  and the indoor units  51 ,  52 ,  53 ,  61 ,  62  and  63  hold beforehand IDs (MAC addresses) that identify themselves. 
     It will be noted that it is necessary to wait for the elapse of start-up time until the outdoor units  50  and  60  reach a predetermined stable state after the outdoor units  50  and  60  start operation. “Start-up time” here means an amount of time required until temperatures that temperature sensors  51   e ,  51   f ,  52   e ,  52   f ,  53   e  and  53   f  (see  FIG. 16 ) disposed in front of indoor heat exchangers  51   a ,  52   a  and  53   a  of the indoor units (see  FIG. 16 ) or in back of the indoor heat exchangers  51   a ,  52   a  and  53   a  detect become stable after causing operation of the outdoor units  50  and  60  to start, and, for example, is a predetermined amount of time determined beforehand by experimental data. As an experiment here, for example, there is a conceivable amount of time that is identified by judging that the outdoor units  50  and  60  have become stable when the difference between detection values of the temperature sensors  51   e ,  51   f ,  52   e ,  52   f ,  53   e  and  53   f  before the outdoor units  50  and  60  start operation and detection values of the temperature sensors  51   e ,  51   f ,  52   e ,  52   f ,  53   e  and  53   f  after the outdoor units  50  and  60  start operation is maintained within the range of a predetermined numerical value during a certain period. Here, the outdoor unit  50  and the outdoor unit  60  may have configurations where the start-up time of the outdoor unit  50  and the start-up time of the outdoor unit  60  differ. 
     Here, the aforementioned air conditioners and the like are, for example, as indicated by the private IP addresses following IPv4 in  FIG. 1 , system-constructed by a network where IPv4 is built in. The network system may also follow IPv6. 
     It will be noted that the outdoor units  50  and  60 , the indoor units  51 ,  52 ,  53 ,  61 ,  62  and  63  and the central controller  40  are only physically connected and can perform communication with each other as a result of IP address setting processing discussed later being performed. 
     Further, although it will be discussed later, at this time, system detection processing that identifies the indoor units that are connected to a given outdoor unit to configure a refrigerant circuit is performed, whereby setting and control according to system becomes possible. 
     &lt;Address Automatic Setting&gt; 
     First, as an outline, a global IP address is allocated such that the router  91  can perform, with the server  70  serving as an external server, communication via the Internet IN using a global UP address. Additionally, the router  91  holds plural types of private IP addresses beforehand in order to assign addresses to plural devices that are locally connected. Further, the router  92  that is connected via the network NW 1  to the router  91  also similarly holds plural types of private IP addresses in order to assign addresses to devices that are locally connected to the router  92 . It will be noted that the outdoor units  50  and  60 , the indoor units  51 ,  52 ,  53 ,  61 ,  62  and  63  and the central controller  40  are divided between and belong to the network NW 1  and the network NW 2  as a result of being mediated by the router  92 . 
     Details thereof will be described below with reference to flowcharts and explanatory drawings. 
       FIG. 3  shows an outline flowchart of address automatic setting. 
     First, to begin, the flow is started by turning the power ON. 
     In step S 10 , automatic assignment of private IP addresses is performed with respect to each air conditioner from the routers  91  and  92 . 
     In step S 20 , respective device information is transmitted to the server  70  from each air conditioner. 
     In step S 30 , refrigerant system detection processing is performed. 
     In step S 40 , indoor unit connection verification is performed. 
     As described above, address automatic setting is performed. Details will be described below in order in each step. 
     (IP Address Automatic Assignment) 
       FIG. 4  shows a flowchart relating to IP address automatic assignment. 
     Here, a DHCP function is utilized to perform assignment of a private IP address with respect to each air conditioner. 
     In step S 11 , each air conditioner that has an ID beforehand transmits a signal requesting a private IP address by broadcasting it to the network (networks NW 1 , NW 2 ) to which that air conditioner belongs. 
     In step S 12 , the routers  91  and  92  that belong to the same network and receive the signal requesting a private IP address send, to each air conditioner, a candidate private IP address from among the private IP addresses that the routers  91  and  92  hold. 
     In step S 13 , each air conditioner transmits a signal requesting private IP address acquisition. 
     In step S 14 , a private IP address allocation notification is sent to each air conditioner from the routers  91  and  92 , and a private IP address correlated with an ID is assigned to each air conditioner. 
     Here, in a state where an address has been assigned to each air conditioner, for example, as shown in  FIG. 8 , there are assigned private IP addresses resulting from 32-bit IPv4 in which binary numbers in octet grouped decimal numbers are written. Private IP addresses resulting from 128-bit IPv6 may also be assigned. 
     (Device Information Collection) 
       FIG. 2  shows an outline sequence of device information collection and delivery resulting from server connection. 
       FIG. 5  shows a flowchart of device information collection and delivery processing by the server  70  resulting from connecting to the server  70 . 
     In step S 21 , each air conditioner transmits device information to the server  70  via the Internet IN. Here, in the router  91 , the private IP address that has been assigned to each air conditioner is converted into a global IP address. The transmission here converts the IP address and port number in the router  91  such that each air conditioner can send device information to the server  70  using one global IP address. 
     In step S 22 , the server  70  creates a device information table on the basis of the device information that has been transmitted from each air conditioner. The device information table here is, for example, as shown in  FIG. 13 , configured by, in regard to the outdoor units  50  and  60  and the indoor units  51 ,  52 ,  53 ,  61 ,  62  and  63 , information indicating whether the device is an outdoor unit or an indoor unit, IDs (MAC addresses), the IP addresses that have been automatically assigned in step S 10 , network addresses, and data identifying parent units of the outdoor units. Of these, the network addresses are addresses corresponding to the networks NW 1  and NW 2 , with the network address corresponding to the network NW 1  being 192.168.10 and the network address corresponding to the network NW 2  being 192.168.20. 
     In step S 23 , the server  70  stands by while creating the device information table until the server  70  is able to acquire device information from all of the air conditioners. Here, the server  70  completes creation of the device information table. The device information table here has the content shown in  FIG. 13 , for example, and is a table where a list of device information of the outdoor units  50  and  60  and the indoor units  51 ,  52 ,  53 ,  61 ,  62  and  63  (whether it is an outdoor unit or an indoor unit; IDs (MAC addresses); private IP addresses; network addresses; etc.) and test operation instruction data that designates parent outdoor units are compiled. It will be noted that, because information indicating whether it is an outdoor unit or an indoor unit is included in the device information in this manner, each air conditioner becomes capable of grasping whether a partner with which it performs IP communication is an indoor unit or an outdoor unit by storing the device information table. 
     In step S 24 , the server  70  delivers the device information that has been created to each air conditioner. Here, a firewall is disposed in the router  91  in order to prevent hacking. For this reason, the method becomes one where, first, the air conditioners transmit a signal requesting the device information table to the server  70  and where, in response thereto, the server  70  sends the device information table to the air conditioners. In this method, IP addresses and port numbers are converted in the router  91 . As a result of the air conditioners separately executing this communication, the device information table is delivered to each air conditioner. 
     Here, in a state where the device information table has been transmitted to each air conditioner, there is constructed a network where the air conditioners are capable of communicating with each other using private IP addresses such as shown in  FIG. 9 , for example. It will be noted that these communications can be realized by utilizing NAT traversal technology such as shown in  FIG. 12 . 
     (System Detection Processing) 
       FIG. 6  shows a flowchart in regard to processing that identifies and discriminates the refrigerant systems that plurally exist in the air conditioning system  100 . 
     The system detection processing here is, for example, as shown in  FIG. 15 , processing for the server  70  to automatically grasp, when the indoor units  51 ,  52  and  53  are connected via a refrigerant pipe D 1  with respect to the outdoor unit  50  to configure one refrigerant system and the indoor units  61 ,  62  and  63  are connected via a refrigerant pipe D 2  with respect to the outdoor unit  60  to configure one refrigerant system, information of these refrigerant systems. Here, the server  70  detects the refrigerant systems by changes in the detection values of the temperature sensors in each indoor unit when the operating state of each outdoor unit is changed one unit at a time. 
     Here, the configuration of the refrigerant circuit that has the outdoor unit  50  and the indoor units  51 ,  52  and  53  and which is one refrigerant system will be described with reference to  FIG. 16 . 
     The outdoor unit  50  has a compressor  21 , a four-way valve  22 , an outdoor heat exchanger  23 , an accumulator  24 , an outdoor expansion valve  25 , a receiver  26 , an outdoor unit controller  27 , an outdoor fan  28 , an intake pressure sensor  29 , a discharge pressure sensor  30 , an intake temperature sensor  31 , a discharge temperature sensor  32 , an outdoor heat exchange temperature sensor  33  and an outdoor temperature sensor  36 . The outdoor unit controller  27  controls the compressor  21  and the outdoor fan  28  by values that the various temperature sensors detect. Specifically, as shown in  FIG. 17 , the outdoor unit controller  27  is equipped with an outdoor unit control component  27   a , a drive component  27   b , a storage component  27   c  and a communication component  27   d . Of these, the drive component  27   b  is connected such that it can transmit control signals to the four-way valve  22  and the compressor  21 . Further, a communication line for communicating with other air conditioners and the server  70  extends from the communication component  27   d . Further, various programs for executing IP address automatic assignment for performing address automatic setting, device information collection, system detection processing and indoor unit connection verification processing are stored in the storage component  27   c.    
     Further, the indoor unit  51  has an indoor heat exchanger  51   a , an indoor fan  51   b , an indoor expansion valve  51   c , an indoor heat exchange temperature sensor  51   d , a liquid side temperature sensor  51   e , a gas side temperature sensor  51   f  and an indoor unit controller  71 . It will be noted that the indoor units  52  and  53  are also the same and that members having corresponding member numbers have corresponding functions, so description thereof will be omitted. The indoor unit controllers  71 ,  72  and  73  perform air volume control of the indoor fan  51   b  by values that the liquid side temperature sensor  51   e  and the gas side temperature sensor  51   f  detect. Specifically, the indoor unit controller  71  has, as shown in  FIG. 17 , an indoor unit control component  71   a , a temperature sensor input component  71   b , a storage component  71   c  and a communication component  71   d . Of these, the temperature sensor input component  71   b  is connected to the various temperature sensors  51   d ,  51   e  and  51   f . Further, a communication line for communicating with other air conditioners and the server  70  extends from the communication component  71   d.    
     Using the above configuration, the server  70  performs the system detection processing discussed below in accordance with the flow shown in  FIG. 6 . 
     In step S 31 , the server  70  verifies whether or not all of the outdoor units  50  and  60  are stopped. Here, when the server  70  verifies that all of the outdoor units  50  and  60  are stopped, the server  70  moves to step S 32 . Here, in  FIG. 18 , which shows the transition of the system detection processing, section  1  represents a time period from when power is turned ON to until the server  70  verifies that the outdoor units are stopped. 
     In step S 32 , the server  70  measures detection values Ts of the indoor heat exchange temperature sensors  51   d ,  52   d ,  53   d , etc., when the outdoor units are stopped. 
     In step S 33 , the server  70  causes all of the outdoor units  50  and  60  to start operation in unison. In  FIG. 18 , this is indicated by the graphs of the outdoor unit  50  and the outdoor unit  60  rising in unison. 
     In step S 34 , the start-up times of the outdoor units  50  and  60  whose operation has been started advance at the same time, and the server  70  waits for the start-up times to elapse. For the start-up times, in  FIG. 18 , a predetermined amount of time is determined beforehand as an amount of time in which section  2 , which is a section from when the outdoor unit  50  and the outdoor unit  60  start operation to until the detection values of the indoor heat exchange temperature sensors  51   d ,  52   d ,  53   d , etc. start changing, elapses and the values detected by the liquid side temperature sensors  51   e ,  52   e  and  53   e  and the gas side temperature sensors  51   f ,  52   f  and  53   f  become constant thereafter in section  3 . For this reason, here, whether or not start-up time has elapsed is judged by whether or not this predetermined amount of time has elapsed after the outdoor units start operation. 
     In step S 35 , the server  70  causes either one of the outdoor unit  50  and the outdoor unit  60  to stop operation. Here, as shown in  FIG. 18 , for the purpose of description, a case where the server  70  causes the outdoor unit  50  to stop will be taken as an example and described. As a result of the server  70  causing the outdoor unit  50  to stop in this manner, the detection values of the indoor heat exchange temperature sensors of the indoor units included in the refrigerant system of the outdoor unit  50  become closer to the values that were measured in the state where operation of the outdoor unit  50  was stopped in step S 32 . 
     In step S 36 , the server  70  measures detection values Tg of the indoor heat exchange temperature sensors  51   d ,  52   d  and  53   d  after operation of the outdoor unit  50  has stopped. 
     In step S 37 , when the temperature difference between the values Ts that the server  70  measured in the state where operation of the outdoor unit  50  was stopped in step S 32  and the values Tg that the server  70  measured in the state where the outdoor unit  50  was stopped in step S 36  is equal to or less than a detection threshold value (set beforehand), the server  70  regards the indoor units  51 ,  52  and  53  having the indoor heat exchange temperature sensors  51   d ,  52   d  and  53   d  as belonging to the same refrigerant system as the outdoor unit  50  and detects them as targets in which the same refrigerant system address as each other is to be held. This is processing that is performed in the time period indicated by section  4  in  FIG. 18 . 
     In step S 38 , the server  70  assigns the same refrigerant system address (e.g., here, the private IP address of the outdoor unit  50 ) to the outdoor unit  50  and the indoor units  51 ,  52  and  53  of the same refrigerant system detected in step S 37  and causes the outdoor unit  50  and the indoor units  51 ,  52  and  53  to store that same refrigerant system address. By using, as the refrigerant system address, the private IP address of the outdoor unit of that system in this manner, it becomes unnecessary for the server  70  to create a separate and new private IP address. 
     In step S 39 , the server  70  judges whether or not all of the outdoor units  50  and  60  have stopped operation, and when all of the outdoor units  50  and  60  have stopped operation, the server  70  ends the system detection processing. Further, if there are outdoor units that are in operation, the server  70  moves to step Sag. 
     In step Sag, the server  70  causes one given outdoor unit to stop from among the outdoor units that are in operation. Here, for the purpose of description, the server  70  causes the outdoor unit  60 , which is the remaining outdoor unit that is in operation, to stop. Then, the server  70  moves to step S 36  and performs the aforementioned processing in the same manner to detect the indoor units of the refrigerant system of the outdoor unit  60 . This is processing that is performed in the time period indicated by section  5  in  FIG. 18 . 
     Because of the above-described processing, the refrigerant systems are grasped and stored, and the fact that the air conditioning system  100  has the networks and refrigerant systems shown in  FIG. 10  is grasped in the server  70 . 
     (Indoor Unit Connection Verification) 
       FIG. 7  shows a flowchart of indoor unit connection verification processing at a stage where a private IP address has been assigned to each air conditioner and refrigerant system detection has also ended. 
     In step S 41 , the outdoor units  50  and  60  transmit signals requesting refrigerant system addresses. 
     In step S 42 , refrigerant system address reply signals are sent from the indoor units  51 ,  52  and  53  to the outdoor unit  50 , and refrigerant system address reply signals are sent from the indoor units  61 ,  62  and  63  to the outdoor unit  60 . 
     In step S 43 , the outdoor units  50  and  60  store the IP addresses of the indoor units in the same system. 
     Thus, the outdoor units  50  and  60  and the indoor units  51 ,  52 ,  53 ,  61 ,  62  and  63  can grasp the connection relationship and refrigerant system relationship such as shown in  FIG. 11  while correlating those relationships with private IP addresses. 
     It will be noted that the individual air conditioners reach a state where they can grasp hierarchical self data such as shown in  FIG. 14 , for example. Further, these communications can be realized by utilizing broadcast router traversal technology such as shown in  FIG. 12 . 
     Due to the above, address setting processing differentiated by refrigerant system ends. 
     &lt;Characteristics of Air Conditioning System  100  Pertaining to Present Embodiment&gt; 
     In a conventional air conditioning system, for example, as shown in  FIG. 19 , refrigerant system detection is performed by causing the outdoor units to start operation one unit at a time and identifying the indoor units in which a temperature change occurs. For this reason, as shown in  FIG. 19 , there arises the need to wait for the elapse of the start-up time of the outdoor unit each time operation of the outdoor units is started for detection of each refrigerant system. For this reason, as a result, it takes a lot of time to detect the refrigerant systems. 
     In contrast, in the air conditioning system  100  of the present embodiment, refrigerant system detection is performed by first placing both of the outdoor units  50  and  60  in a driven state and thereafter stopping, one unit at a time, the outdoor unit on which refrigerant system detection is to be performed. For this reason, when detecting the refrigerant system of each outdoor unit, it suffices simply to stop the outdoor unit, and it is not necessary to wait for the elapse of the start-up time. For this reason, it becomes possible to perform refrigerant system detection in a shorter amount of time than the conventional method. 
     &lt;Modifications of Air Conditioning System  100 &gt; 
     An embodiment of the present invention has been described above on the basis of the drawings, but the specific configuration thereof is not limited to this embodiment and is alterable in a scope that does not depart from the gist of the invention. 
     In the preceding embodiment, a case where control that causes the outdoor units  50  and  60  in operation to stop is performed for refrigerant system detection has been taken as an example and described. 
     However, the present invention is not limited to this and may also be configured such that, rather than completely stopping the outdoor units  50  and  60  in operation, for example, as shown in  FIG. 17 , control that weakens the output that drives the compressor  21  is performed by the outdoor unit control component  27   a  and the drive component  27   b . In this case also, the values of the temperature sensors of the indoor units of the same refrigerant system also change, so the refrigerant system can be detected in the same manner as in the preceding embodiment. 
     INDUSTRIAL APPLICABILITY 
     By utilizing the present invention, it becomes possible to perform refrigerant system detection in a short amount of time, so the invention can be used particularly as a method of automatically detecting refrigerant systems of an air conditioning system configured by plural outdoor units and indoor units.