JP2017009268A - Air-conditioning system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air-conditioning system which: includes a cooling medium circuit where an outdoor unit having a compressor and an outdoor heat exchanger and an indoor unit having an indoor heat exchanger are connected to each other through a cooling medium communication pipe and cutoff valves to close a liquid cooling medium pipe and a gas cooling medium pipe when a leakage of a cooling medium is detected; and can reliably perform an operation check including cutoff performance of the cutoff valves.SOLUTION: As a cutoff valve inspection process for an operation check of a liquid side cutoff valve 7 and a gas side cutoff valve 8, an air-conditioning system 1: performs operation of a compressor 21 with the liquid side cutoff valve and the gas side cutoff valve opened; and, on the basis of a change in pressure of a cooling medium after closing either the liquid side cutoff valve or the gas side cutoff valve, determines whether or not the closed cutoff valve normally operates.SELECTED DRAWING: Figure 1

Description

  The present invention includes a refrigerant circuit configured by connecting an outdoor unit having a compressor and an outdoor heat exchanger and an indoor unit having an indoor heat exchanger via a refrigerant communication pipe, and the liquid side of the outdoor unit Leakage of refrigerant is detected from the liquid refrigerant pipe from the end to the liquid side end of the indoor heat exchanger and the gas refrigerant pipe from the gas side end of the outdoor unit to the gas side end of the indoor heat exchanger The present invention relates to an air conditioning system provided with a shut-off valve that is closed when the operation is performed.

  Conventionally, there is an air conditioning system including a refrigerant circuit configured by connecting an outdoor unit having a compressor and an outdoor heat exchanger and an indoor unit having an indoor heat exchanger via a refrigerant communication pipe. In such an air conditioning system, in order to reduce the amount of leakage when refrigerant leakage occurs, the liquid refrigerant pipe from the liquid side end of the outdoor unit to the liquid side end of the indoor heat exchanger, and the outdoor A shutoff valve that is closed when refrigerant leakage is detected may be provided for the gas refrigerant pipe from the gas side end of the unit to the gas side end of the indoor heat exchanger. And in such an air conditioning system, as shown in patent document 1 (Unexamined-Japanese-Patent No. 2013-19621), at the time of a periodic inspection etc., opening / closing operation of the shut-off valve is performed, Whether or not the shut-off valve is operating normally is determined by operating noise and vibration.

  However, in the conventional method for confirming the operation of the shut-off valve by operating noise and vibration, when the shut-off valve is closed, the shut-off shut-off valve is actually closed and the desired shut-off performance is obtained. It is impossible to determine whether the valve leakage amount in the closed state is secured.

  An object of the present invention includes a refrigerant circuit configured by connecting an outdoor unit having a compressor and an outdoor heat exchanger and an indoor unit having an indoor heat exchanger via a refrigerant communication pipe, and a liquid refrigerant pipe In addition, in an air conditioning system provided with a shut-off valve that is closed when refrigerant leakage is detected with respect to the gas refrigerant pipe, an operation check including shut-off performance of the shut-off valve can be reliably performed.

  An air conditioning system according to a first aspect is configured by connecting an outdoor unit having a compressor and an outdoor heat exchanger and an indoor unit having an indoor heat exchanger via a liquid refrigerant communication tube and a gas refrigerant communication tube. A refrigerant circuit. The air conditioning system includes a liquid refrigerant pipe from the liquid side end of the outdoor unit including the liquid refrigerant communication pipe to the liquid side end of the indoor heat exchanger, and the gas side of the outdoor unit including the gas refrigerant communication pipe A liquid side shut-off valve and a gas side shut-off valve are provided that are closed when refrigerant leakage is detected in the gas refrigerant pipe from the end to the gas side end of the indoor heat exchanger. In the air conditioning system, the system control unit that controls the components including the liquid side shutoff valve and the gas side shutoff valve performs the shutoff valve inspection process for confirming the operation of the liquid side shutoff valve and the gas side shutoff valve. It has become. Here, the outdoor unit is provided with a suction pressure sensor for detecting the pressure of the refrigerant on the suction side of the compressor. In the shut-off valve inspection process, the compressor is operated in a state where the outdoor heat exchanger functions as a refrigerant radiator with the liquid-side shut-off valve and the gas-side shut-off valve opened. Based on the change in the pressure value of the refrigerant detected by the suction pressure sensor when one of the side shut-off valve and the gas side shut-off valve is closed, one of the closed liquid-side shut-off valve and the gas-side shut-off valve is operating normally. It is to determine whether or not it is operating.

  As described above, the compressor is operated in a state in which both the liquid side shutoff valve and the gas side shutoff valve are opened and the outdoor heat exchanger functions as a refrigerant radiator (cooling cycle state). When one of the opened liquid side shutoff valve and gas side shutoff valve is closed during operation, the refrigerant pressure on the suction side of the compressor suddenly increases if the closed shutoff valve is operating normally. However, if the shut-off valve that has been closed is not operating normally, the pressure of the refrigerant on the suction side of the compressor does not tend to decrease rapidly. As described above, when one of the opened liquid side shut-off valve and gas side shut-off valve is closed during operation of the compressor in the cooling cycle state, the refrigerant detected by the suction pressure sensor at this time is detected. Based on the change in the pressure value, it can be determined whether one of the closed liquid-side shut-off valve and the gas-side shut-off valve is operating normally including the shut-off performance.

  Thereby, here, the operation check including the shutoff performance of the liquid side shutoff valve and the gas side shutoff valve can be reliably performed.

  In the air conditioning system according to the second aspect, in the air conditioning system according to the first aspect, in the shut-off valve inspection process, is one of the closed liquid-side shut-off valve and gas-side shut-off valve operating normally? After determining whether or not, the opening operation of one of the liquid-side shut-off valve and the gas-side shut-off valve that is closed is performed, and then the suction pressure sensor when the other of the liquid-side shut-off valve and the gas-side shut-off valve is closed is Based on the change in the pressure value of the refrigerant to be detected, it is determined whether the other of the closed liquid-side shutoff valve and gas-side shutoff valve is operating normally.

  Here, as described above, after confirming the operation of one of the liquid side shutoff valve and the gas side shutoff valve, both the liquid side shutoff valve and the gas side shutoff valve are opened, and the compressor is operated in the cooling cycle state. Based on the change in the pressure value of the refrigerant detected by the suction pressure sensor at this time by closing the other of the liquid side shut-off valve and the gas side shut-off valve that have not been checked for operation after returning to the operating state. Thus, it is determined whether the other of the closed liquid-side shutoff valve and gas-side shutoff valve is operating normally.

  Thereby, here, the operation check including the shutoff performance of the liquid side shutoff valve and the gas side shutoff valve can be reliably performed.

  An air conditioning system according to a third aspect is configured by connecting an outdoor unit having a compressor and an outdoor heat exchanger and an indoor unit having an indoor heat exchanger via a liquid refrigerant communication tube and a gas refrigerant communication tube. A refrigerant circuit. The air conditioning system includes a liquid refrigerant pipe from the liquid side end of the outdoor unit including the liquid refrigerant communication pipe to the liquid side end of the indoor heat exchanger, and the gas side of the outdoor unit including the gas refrigerant communication pipe A liquid side shut-off valve and a gas side shut-off valve are provided that are closed when refrigerant leakage is detected in the gas refrigerant pipe from the end to the gas side end of the indoor heat exchanger. In the air conditioning system, the system control unit that controls the components including the liquid side shutoff valve and the gas side shutoff valve performs the shutoff valve inspection process for confirming the operation of the liquid side shutoff valve and the gas side shutoff valve. It has become. Here, the outdoor unit is provided with a discharge pressure sensor for detecting the pressure of the refrigerant on the discharge side of the compressor. In the shut-off valve inspection process, the compressor is operated with the outdoor heat exchanger functioning as a refrigerant evaporator with the liquid-side shut-off valve and the gas-side shut-off valve opened. Based on the change in the pressure value of the refrigerant detected by the discharge pressure sensor when one of the side shut-off valve and gas side shut-off valve is closed, one of the closed liquid-side shut-off valve and gas side shut-off valve is operating normally. It is to determine whether or not it is operating.

  As described above, when the compressor is operated in a state where the outdoor heat exchanger functions as a refrigerant evaporator (heating cycle state), one of the opened liquid side shut-off valve and gas side shut-off valve is When the closing operation is performed, if the closed shut-off valve operates normally, the refrigerant pressure on the discharge side of the compressor tends to increase rapidly, but the closed shut-off valve operates normally. Otherwise, there is no tendency for the refrigerant pressure on the discharge side of the compressor to increase rapidly. Thus, when the compressor is operated in the heating cycle state, if one of the opened liquid side shut-off valve and gas side shut-off valve is closed, the refrigerant pressure detected by the discharge pressure sensor at this time is detected. Based on the change in the pressure value, it can be determined whether one of the closed liquid-side shut-off valve and the gas-side shut-off valve is operating normally including the shut-off performance.

  Thereby, here, the operation check including the shutoff performance of the liquid side shutoff valve and the gas side shutoff valve can be reliably performed.

  In the air-conditioning system according to the fourth aspect, in the air-conditioning system according to the third aspect, is the shut-off valve check process in which one of the closed liquid-side shut-off valve and the gas-side shut-off valve is operating normally? After determining whether or not, the opening operation of one of the liquid-side shut-off valve and the gas-side shut-off valve that is closed is performed, and then the discharge pressure sensor when the other of the liquid-side shut-off valve and the gas-side shut-off valve is closed is Based on the change in the pressure value of the refrigerant to be detected, it is determined whether the other of the closed liquid-side shutoff valve and gas-side shutoff valve is operating normally.

  Here, as described above, after confirming the operation of one of the liquid side shutoff valve and the gas side shutoff valve, both the liquid side shutoff valve and the gas side shutoff valve are opened and the compressor is operated in the heating cycle state. Based on the change in the pressure value of the refrigerant detected by the discharge pressure sensor at this time by closing the other one of the liquid side shut-off valve and the gas side shut-off valve that has not been checked for operation after returning to the operating state. Thus, it is determined whether the other of the closed liquid-side shutoff valve and gas-side shutoff valve is operating normally.

  Thereby, here, the operation check including the shutoff performance of the liquid side shutoff valve and the gas side shutoff valve can be reliably performed.

  An air conditioning system according to a fifth aspect is the air conditioning system according to any of the first to fourth aspects, wherein there are a plurality of indoor units, and a liquid side cutoff valve and a gas side cutoff valve are provided in each indoor unit. Correspondingly, the liquid refrigerant pipe and the gas refrigerant pipe are provided. Here, the system control unit performs shut-off valve inspection processing on the corresponding liquid-side shut-off valve and gas-side shut-off valve for one indoor unit among the plurality of indoor units, and shuts off the plurality of indoor units. Operation is stopped for indoor units that are not subject to valve inspection processing.

  In an air conditioning system having a plurality of indoor units, a liquid-side shut-off valve and a gas-side shut-off valve corresponding to each indoor unit are provided, and a shut-off valve inspection process is performed simultaneously for a plurality of liquid-side shut-off valves and gas-side shut-off valves. Change of the pressure value due to the closing operation of multiple liquid side shutoff valves and gas side shutoff valves occurs at the same time, which shutoff valve is operating normally (or which shutoff valve is operating normally) Cannot be distinguished).

  Therefore, here, as described above, for one indoor unit among the plurality of indoor units, while performing the shut-off valve inspection process for the corresponding liquid-side shut-off valve and gas-side shut-off valve, Among them, the operation is stopped for indoor units that are not subject to shut-off valve inspection processing. For this reason, it is possible to determine whether or not the operation is normally performed after distinguishing whether there is a change in the pressure value due to the closing operation of the shut-off valve from the shut-off valve that is the target of the shut-off valve inspection process. .

  As a result, even if the liquid-side shut-off valve and the gas-side shut-off valve corresponding to each of the plurality of indoor units are provided, the operation check including the shut-off performance is sequentially performed for the plurality of shut-off valves. It can be determined whether each shut-off valve is operating normally.

  In the air conditioning system according to the sixth aspect, in the air conditioning system according to any one of the first to fifth aspects, the system control unit is connected to a refrigerant leakage detection device that detects the presence or absence of refrigerant leakage. Yes. Here, in the shut-off valve inspection process, the system control unit inputs a signal indicating the presence or absence of refrigerant leak output from the refrigerant leak detection device to the system control unit by simulating the liquid side shut-off valve and gas side shut-off. A simulated input permission unit is provided for permitting the opening / closing operation of the valve.

  As described above, when the shut-off valve inspection process is performed by simulating the opening / closing operation of the liquid-side shut-off valve and the gas-side shut-off valve by inputting a signal indicating the presence or absence of refrigerant leak output from the refrigerant leak detection device. The system control unit needs to be able to distinguish whether the signal output from the refrigerant leakage detection device is a simulated input or a signal indicating the presence or absence of actual refrigerant leakage. This is because when the signal indicating that the refrigerant is leaking is input from the refrigerant leak detection device, the liquid side shutoff valve and the gas side shutoff valve are closed. At this time, the system control unit Operations necessary for shut-off valve check processing such as operating the compressor in the cooling cycle state by closing the liquid side shut-off valve and gas side shut-off valve, judging that refrigerant leakage has occurred It is because it becomes impossible to perform.

  Therefore, here, as described above, in the shut-off valve inspection process, the liquid side shut-off valve and the gas are input by simulating the signal indicating the presence or absence of the refrigerant leak output from the refrigerant leak detection device to the system control unit. The system control unit is provided with a simulated input permission unit for permitting the opening / closing operation of the side shut-off valve. For this reason, by permitting the shut-off valve inspection process to be performed by inputting a signal indicating the presence or absence of refrigerant leakage output from the refrigerant leakage detection device using the simulated input permission unit, the system control unit can It is possible to prevent the occurrence of leakage and to perform an operation necessary for the shut-off valve inspection process such as operating the compressor in the cooling cycle state or the heating cycle state.

  As a result, the shutoff valve inspection process can be performed here by simulating the signal indicating the presence or absence of refrigerant leakage output from the refrigerant leakage detection device into the system control unit. And the communication connection between the refrigerant leakage detection device and the liquid side shut-off valve and the gas side shut-off valve can be confirmed.

  As described above, according to the present invention, the refrigerant configured by connecting the outdoor unit having the compressor and the outdoor heat exchanger and the indoor unit having the indoor heat exchanger via the refrigerant communication pipe. In an air conditioning system that includes a circuit and is provided with a shut-off valve that closes when a refrigerant leak is detected in the liquid refrigerant pipe and gas refrigerant pipe, ensure operation check including shut-off performance of the shut-off valve To be able to do so.

It is a schematic block diagram of the air conditioning system concerning 1st Embodiment of this invention. It is a control block diagram (the outdoor control part and the indoor control part are shown in detail) of the air conditioning system according to the first embodiment of the present invention. It is a control block diagram (a shut-off valve control part and a refrigerant leak detection part are shown in detail) of an air harmony system concerning a 1st embodiment of the present invention. It is a flowchart of the shut-off valve check process (process by the driving | operation of the compressor in a cooling cycle state) in the air conditioning system concerning 1st Embodiment of this invention. It is a flowchart of the shut-off valve check process (process by the driving | operation of the compressor in a heating cycle state) in the air conditioning system concerning 1st Embodiment of this invention. It is a control block diagram (an outdoor control part and an indoor control part are shown in detail) of the air conditioning system concerning the modification of 1st Embodiment of this invention. It is a schematic block diagram of the air conditioning system concerning 2nd Embodiment of this invention. It is a control block diagram (the outdoor control part and the indoor control part are shown in detail) of the air conditioning system according to the second embodiment of the present invention. It is a control block diagram (a shut-off valve control part and a refrigerant leak detection part are shown in detail) of an air harmony system concerning a 2nd embodiment of the present invention. It is a flowchart of the shut-off valve check process (process by the driving | operation of the compressor in a cooling cycle state) in the air conditioning system concerning 2nd Embodiment of this invention. It is a flowchart of the shut-off valve check process (process by the driving | operation of the compressor in a heating cycle state) in the air conditioning system concerning 2nd Embodiment of this invention. It is a control block diagram (an outdoor control part and an indoor control part are shown in detail) of the air conditioning system concerning the modification 1 of 2nd Embodiment of this invention.

  Hereinafter, an embodiment of an air conditioning system according to the present invention will be described with reference to the drawings. In addition, the concrete structure of embodiment of the air conditioning system concerning this invention is not restricted to the following embodiment and its modification, It can change in the range which does not deviate from the summary of invention.

<First Embodiment>
(1) Configuration-Overall-
FIG. 1 is a schematic configuration diagram of an air conditioning system 1 according to the first embodiment of the present invention.

  The air conditioning system 1 is a system that cools or heats a room such as a building by a vapor compression refrigeration cycle. The air conditioning system 1 mainly includes a vapor compression refrigerant circuit 10 configured by connecting an outdoor unit 2 and an indoor unit 4 via a liquid refrigerant communication tube 5 and a gas refrigerant communication tube 6. The outdoor unit 2 is installed outdoors, and mainly includes a compressor 21 and an outdoor heat exchanger 24. The indoor unit 4 is installed indoors and has an indoor heat exchanger 42. The refrigerant circuit 10 is filled with a refrigerant having a slight flammability such as R32 or a refrigerant having a strong flammability such as R290.

  Further, the air conditioning system 1 includes a liquid refrigerant pipe 50 extending from the liquid side end of the outdoor unit 2 including the liquid refrigerant communication pipe 5 to the liquid side end of the indoor heat exchanger 42, and a gas refrigerant communication pipe 6. The liquid side shut-off valve 7 and the gas which are closed when refrigerant leakage is detected in the gas refrigerant pipe 60 from the gas side end of the outdoor unit 2 including the gas to the gas side end of the indoor heat exchanger 42. A side shut-off valve 8 is provided. Here, a liquid side closing valve 26 and a gas side closing valve 27 which are manually opened and closed are provided at the liquid side end and the gas side end of the outdoor unit 2. The indoor unit 4 includes an indoor liquid refrigerant tube 43 that connects the liquid refrigerant communication tube 5 and the liquid side end of the indoor heat exchanger 42, a gas refrigerant communication tube 6 and the gas side end of the indoor heat exchanger 42. And an indoor gas refrigerant pipe 44 to be connected. Therefore, the liquid refrigerant pipe 50 means a refrigerant pipe composed of the liquid refrigerant communication pipe 5 and the indoor liquid refrigerant pipe 43, and the gas refrigerant pipe 60 is a refrigerant composed of the gas refrigerant communication pipe 6 and the indoor gas refrigerant pipe 44. Means a tube. The liquid side shutoff valve 7 and the gas side shutoff valve 8 are valves that are closed when leakage of the refrigerant is detected. Here, the liquid side shutoff valve 7 is the liquid refrigerant communication pipe 5 in the liquid refrigerant pipe 50. The gas side shut-off valve 8 is provided in a portion of the gas refrigerant pipe 60 near the indoor unit 4 of the gas refrigerant communication pipe 6. Further, unlike the manual valves such as the liquid side shutoff valve 26 and the gas side shutoff valve 27, the liquid side shutoff valve 7 and the gas side shutoff valve 8 are signals indicating whether or not refrigerant has leaked from the outside, and open / close commands. It consists of an automatic valve that is opened and closed in response to a signal. Here, in order to detect the presence or absence of refrigerant leakage, a refrigerant leakage detection device 9 is provided in the room.

  The air conditioning system 1 is provided with a system control unit 11 that controls components including the liquid-side cutoff valve 7 and the gas-side cutoff valve 8. The system control unit 11 includes an outdoor control unit 20 that controls the components of the outdoor unit 2, an indoor control unit 40 that controls the components of the indoor unit 4, and a liquid-side cutoff control unit 70 that controls the liquid-side cutoff valve 7. And a gas-side cutoff control unit 80 that controls the gas-side cutoff valve 8 is connected via a communication line. The outdoor control unit 20 is provided in the outdoor unit 2. The indoor control unit 40 is provided in the indoor unit 4. The liquid side cutoff control unit 70 is provided in the liquid side cutoff valve 7, and the gas side cutoff control unit 80 is provided in the gas side cutoff valve 8. The system controller 11 is also connected to a refrigerant leak detection controller 90 that controls the refrigerant leak detector 9. The refrigerant leakage detection control unit 90 is provided in the refrigerant leakage detection device 9. Note that here, wired communication in which the controllers 20, 40, 70, 80, and 90 are connected via a communication line is adopted, but the present invention is not limited to this, and other wireless communication and other devices are used. It may be a communication format.

-Outdoor unit-
As described above, the outdoor unit 2 is connected to the indoor unit 4 via the refrigerant communication pipes 5 and 6 and constitutes a part of the refrigerant circuit 10.

  The outdoor unit 2 mainly includes a compressor 21, a switching mechanism 23, an outdoor heat exchanger 24, an outdoor expansion valve 25, a liquid side closing valve 26, and a gas side closing valve 27.

  The compressor 21 is a mechanism for compressing a refrigerant, and here, a rotary type or scroll type volumetric compression element (not shown) accommodated in a casing (not shown) is also provided in the casing. A hermetic compressor driven by a stored compressor motor 22 is employed.

  The switching mechanism 23 is a four-way switching valve capable of switching between a cooling cycle state in which the outdoor heat exchanger 24 functions as a refrigerant radiator and a heating cycle state in which the outdoor heat exchanger 24 functions as a refrigerant evaporator. Here, the cooling cycle state is a switching state in which the discharge side of the compressor 21 and the gas side end of the outdoor heat exchanger 24 are communicated, and the gas refrigerant communication pipe 6 and the suction side of the compressor 21 are communicated. (Refer to the solid line of the switching mechanism 23 in FIG. 1). The heating cycle state is a switching state in which the discharge side of the compressor 21 and the gas refrigerant communication pipe 6 communicate with each other, and the gas side end of the outdoor heat exchanger 24 communicates with the suction side of the compressor 21 (see FIG. 1). (Refer to the broken line of the switching mechanism 23). The switching mechanism 23 is not limited to a four-way switching valve, and is configured to have a function of switching the flow direction of the refrigerant as described above, for example, by combining a plurality of electromagnetic valves. There may be.

  The outdoor heat exchanger 24 is a heat exchanger that functions as a refrigerant radiator or evaporator by exchanging heat between the refrigerant and outdoor air. The outdoor air that exchanges heat with the refrigerant in the outdoor heat exchanger 24 is supplied by an outdoor fan 28 that is driven by an outdoor fan motor 29.

  The outdoor expansion valve 25 is a mechanism that depressurizes the refrigerant. Here, an electric expansion valve capable of opening degree control is employed.

  As described above, the liquid side closing valve 26 and the gas side closing valve 27 are valves that are manually opened and closed provided at the liquid side end and the gas side end of the outdoor unit 2.

  The outdoor unit 2 is provided with various sensors. Specifically, around the compressor 21 of the outdoor unit 2, a suction pressure sensor 35 for detecting the refrigerant pressure Ps on the suction side of the compressor 21 and a refrigerant pressure Pd on the discharge side of the compressor 21 are detected. And a discharge pressure sensor 36.

-Indoor unit-
As described above, the indoor unit 4 is connected to the outdoor unit 2 through the refrigerant communication pipes 5 and 6 and constitutes a part of the refrigerant circuit 10.

  The indoor unit 4 mainly has an indoor heat exchanger 42.

  The indoor heat exchanger 42 is a heat exchanger that functions as an evaporator or a radiator of the refrigerant by exchanging heat between the refrigerant and the room air. The indoor air that exchanges heat with the refrigerant in the indoor heat exchanger 42 is supplied by an indoor fan 45 driven by an indoor fan motor 46.

  The indoor unit 4 is provided with various sensors. Specifically, the indoor unit 4 includes an indoor heat exchange liquid side sensor 47 that detects the refrigerant temperature Trl at the liquid side end of the indoor heat exchanger 42, and a temperature Tra of the indoor air sucked into the indoor unit 4. And an indoor air sensor 48 for detecting.

-System control unit and refrigerant leakage detection control unit-
2 is a control block diagram of the air conditioning system 1 (the outdoor control unit 20 and the indoor control unit 40 are shown in detail), and FIG. 3 is a control block diagram of the air conditioning system 1 (shut-off valve control units 70 and 80). And the refrigerant leakage detection unit 90 is shown in detail).

  The outdoor control unit 20 controls the operation of the outdoor unit 2 and constitutes a part of the system control unit 11. The outdoor control unit 20 mainly includes an outdoor CPU 121, an outdoor communication unit 122, an outdoor storage unit 123, an outdoor operation unit 124, and an outdoor display unit 125. The outdoor CPU 121 is connected to the outdoor communication unit 122, the outdoor storage unit 123, the outdoor operation unit 124, and the outdoor display unit 125. The outdoor communication unit 122 communicates control data and the like between the indoor control units 40. The outdoor storage unit 123 stores control data and the like. The outdoor operation unit 124 inputs a control command and the like. The outdoor display unit 125 displays (outputs) the operation state and the like. The outdoor CPU 121 receives input of control commands and the like and communicates control data and the like via the outdoor communication unit 122 and the outdoor operation unit 124, reads and writes control data and the like to the outdoor storage unit 123, and the outdoor display unit While displaying the operation state and the like in 125, detection of state quantities by the various sensors 35 and 36 and operation control of the constituent devices 21, 23, 25, and 28 of the outdoor unit 2 are performed.

  The indoor control unit 40 controls the operation of the indoor unit 4 and constitutes a part of the system control unit 11. The indoor control unit 40 mainly includes an indoor CPU 141, an indoor communication unit 142, an indoor storage unit 143, an indoor operation unit 144, and an indoor display unit 145. The indoor CPU 141 is connected to the indoor communication unit 142, the indoor storage unit 143, the indoor operation unit 144, and the indoor display unit 145. The indoor communication unit 142 communicates control data and the like with the outdoor control unit 20, the liquid side cutoff control unit 70, the gas side cutoff control unit 80, and the refrigerant leakage detection control unit 90. The indoor storage unit 143 stores control data and the like. The indoor operation unit 144 inputs a control command and the like. The indoor display unit 145 displays (outputs) the operation state and the like. The indoor CPU 141 receives input of control commands and the like and communicates control data and the like via the indoor communication unit 142 and the indoor operation unit 144, reads and writes control data and the like to the indoor storage unit 143, and displays the indoor display unit. While displaying the operation state and the like in 145, detection of state quantities by various sensors 47 and 48 and operation control of the constituent devices 45 of the indoor unit 4 are performed. When a remote controller is provided corresponding to the indoor unit 4, the remote controller also constitutes the indoor control unit 40.

  The liquid side shutoff control unit 70 controls the opening and closing of the liquid side shutoff valve 7 and constitutes a part of the system control unit 11. The liquid side cutoff control unit 70 mainly includes a liquid side cutoff CPU 171, a liquid side cutoff communication unit 172, and a liquid side cutoff storage unit 173. The liquid side cutoff CPU 171 is connected to the liquid side cutoff communication unit 172 and the liquid side cutoff storage unit 173. The liquid side cutoff communication unit 172 communicates control data and the like between the indoor control units 40. The liquid side interruption | blocking memory | storage part 173 memorize | stores control data etc. The liquid side cutoff CPU 171 communicates control data and the like via the liquid side cutoff communication unit 172, reads and writes the control data and the like to the liquid side cutoff storage unit 173, and controls the opening and closing of the liquid side cutoff valve 7. .

  The gas side shutoff control unit 80 controls opening and closing of the gas side shutoff valve 8 and constitutes a part of the system control unit 11. The gas side cutoff control unit 80 mainly includes a gas side cutoff CPU 181, a gas side cutoff communication unit 182, and a gas side cutoff storage unit 183. The gas side cutoff CPU 181 is connected to the gas side cutoff communication unit 182 and the gas side cutoff storage unit 183. The gas-side cutoff communication unit 182 communicates control data and the like between the indoor control units 40. The gas side cutoff storage unit 183 stores control data and the like. Then, the gas-side cutoff CPU 181 communicates control data and the like via the gas-side cutoff communication unit 182, reads and writes control data and the like in the gas-side cutoff storage unit 183, and controls the opening and closing of the gas-side cutoff valve 8. .

  The refrigerant leakage detection control unit 90 performs detection control of the refrigerant leakage detection device 9 and is connected to the system control unit 11. The refrigerant leakage detection control unit 90 mainly includes a detection CPU 191, a detection communication unit 192, and a detection storage unit 193. The detection CPU 191 is connected to the detection communication unit 192 and the detection storage unit 193. The detection communication unit 192 communicates control data and the like between the indoor control units 40. The detection storage unit 193 stores control data and the like. The detection CPU 191 communicates control data and the like via the detection communication unit 192, reads and writes control data and the like in the detection storage unit 193, and performs detection control of the refrigerant leakage detection device 9.

  Also, here, the indoor CPU 141 of the indoor control unit 40 has a normal operation processing unit 146 for executing normal operation processing including cooling operation and heating operation, and a shut-off valve 7 that is performed when refrigerant leakage is detected. The refrigerant leakage processing unit 147 for executing the refrigerant leakage processing including the closing of 8 and the shutoff valve inspection processing for executing the shutoff valve inspection processing including the operation check of the shutoff valves 7 and 8 performed for periodic inspection and the like. Part 148.

(2) Operation-Normal operation-
In the air conditioning system 1, the cooling operation and the heating operation are performed as the normal operation.

  First, the cooling operation will be described. When an instruction for cooling operation is given to the system control unit 11 via the indoor operation unit 144 or the like of the indoor control unit 40, the normal cooling processing unit 146 of the indoor CPU 141 executes the following cooling operation.

  Specifically, the switching mechanism 23 is switched to the cooling cycle state (the state indicated by the solid line of the switching mechanism 23 in FIG. 1), and the compressor 21, the outdoor fan 28, and the indoor fan 45 are started. Here, since no refrigerant leak occurs (that is, no refrigerant leak is detected in the refrigerant leak detection device 9), both the liquid side shutoff valve 7 and the gas side shutoff valve 8 are opened. It is in a state. Then, the refrigerant discharged from the compressor 21 is sent to the outdoor heat exchanger 24 via the switching mechanism 23. The refrigerant sent to the outdoor heat exchanger 24 is condensed by being cooled by performing heat exchange with outdoor air supplied by the outdoor fan 28 in the outdoor heat exchanger 24 functioning as a radiator of the refrigerant. This refrigerant is sent to the outdoor expansion valve 25. The refrigerant sent to the outdoor expansion valve 25 is depressurized in the outdoor expansion valve 25, and passes through the liquid side closing valve 26 and the liquid refrigerant pipe 50 (the liquid refrigerant communication pipe 5, the liquid side shutoff valve 7, and the indoor liquid refrigerant pipe 43). Then, it is sent to the indoor heat exchanger 42. The refrigerant sent to the indoor heat exchanger 42 evaporates by being heated by exchanging heat with indoor air supplied from the room indoors by the indoor fan 45 in the indoor heat exchanger 42 functioning as a refrigerant evaporator. . This refrigerant is sucked into the compressor 21 via the gas refrigerant pipe 60 (the indoor gas refrigerant pipe 44, the gas refrigerant communication pipe 6, and the gas side shutoff valve 8), the gas side closing valve 27, and the switching mechanism 23. On the other hand, the room air cooled in the indoor heat exchanger 42 is sent into the room, thereby cooling the room.

  Next, the heating operation will be described. When a heating operation instruction is given to the system control unit 11 via the indoor operation unit 144 of the indoor control unit 40, the following heating operation is executed by the normal operation processing unit 146 of the indoor CPU 141.

  Specifically, the switching mechanism 23 is switched to the heating cycle state (the state indicated by the broken line of the switching mechanism 23 in FIG. 1), and the compressor 21, the outdoor fan 28, and the indoor fan 45 are started. Here, since no refrigerant leak occurs (that is, no refrigerant leak is detected in the refrigerant leak detection device 9), both the liquid side shutoff valve 7 and the gas side shutoff valve 8 are opened. It is in a state. Then, the refrigerant discharged from the compressor 21 passes through the switching mechanism 23, the gas side closing valve 27, and the gas refrigerant pipe 60 (the gas refrigerant communication pipe 6, the gas side shutoff valve 8, and the indoor gas refrigerant pipe 44). It is sent to the indoor heat exchanger 42. The refrigerant sent to the indoor heat exchanger 42 is condensed by cooling the indoor heat exchanger 42 functioning as a refrigerant radiator by exchanging heat with the indoor air supplied from the room by the indoor fan 45. . This refrigerant is sent to the outdoor expansion valve 25 via the liquid refrigerant pipe 50 (the indoor liquid refrigerant pipe 43, the liquid refrigerant communication pipe 5, and the liquid side shut-off valve 7) and the liquid side closing valve 26. On the other hand, the indoor air heated in the indoor heat exchanger 42 is sent indoors, thereby heating the room. The refrigerant sent to the outdoor expansion valve 25 is decompressed by the outdoor expansion valve 25 and sent to the outdoor heat exchanger 24. The refrigerant sent to the outdoor heat exchanger 24 evaporates by being heated by exchanging heat with the outdoor air supplied by the outdoor fan 28 in the outdoor heat exchanger 24 functioning as a refrigerant evaporator. This refrigerant is sucked into the compressor 21 via the switching mechanism 23.

-Refrigerant leakage treatment-
In the above normal operation, when refrigerant leakage is detected, it is necessary to close the liquid side shutoff valve 7 and the gas side shutoff valve 8 in order to reduce the amount of refrigerant leaked into the room. Therefore, when a signal indicating that a refrigerant leak is output from the refrigerant leakage detection device 9 (refrigerant leakage detection control unit 90) is input to the system control unit 11 (indoor control unit 40), the indoor CPU 141 is displayed. The refrigerant leakage processing unit 147 performs the following refrigerant leakage processing.

  Specifically, the liquid side shutoff valve 7 and the gas side shutoff valve 8 are closed to eliminate the flow of refrigerant from the outdoor unit 2 to the indoor unit 4. The compressor 21 is also stopped. Thereby, the leakage amount of the refrigerant | coolant to a room | chamber interior can be reduced, and generation | occurrence | production of the ignition accident in a room | chamber interior can be suppressed here so that the combustible refrigerant | coolant may not exceed combustible density | concentration.

-Check valve check process-
The refrigerant leakage process using the shut-off valves 7 and 8 is an effective means for preventing accidents due to refrigerant leakage. In order to ensure that the refrigerant leakage process is performed, It is necessary that the liquid side shut-off valve 7 and the gas side shut-off valve 8 are actually closed by the closing operation when leakage is detected, and a desired shut-off performance is ensured. On the other hand, it is conceivable to check the operation of the liquid-side shut-off valve 7 and the gas-side shut-off valve 8 during periodic inspections. In the method of confirming the operation by vibration or vibration, when the shut-off valve is closed, the shut-off shut-off valve is actually in the closed state, and the desired shut-off performance (valve leak amount in the closed state, etc.) There is a problem that it is impossible to determine whether it is secured, and it is not possible to check the operation including the shutoff performance of the shutoff valve.

  Therefore, here, as a shut-off valve check process for confirming the operation of the liquid-side shut-off valve 7 and the gas-side shut-off valve 8, the compressor 21 is operated with the liquid-side shut-off valve 7 and the gas-side shut-off valve 8 being opened. Based on the change in the pressure value of the refrigerant when one of the liquid-side shut-off valve 7 and the gas-side shut-off valve 8 is closed after that, whether the shut-off shut-off valve is operating normally is determined. Judgment is made. More specifically, when the compressor 21 is operated with both the liquid-side shut-off valve 7 and the gas-side shut-off valve 8 opened, the opened liquid-side shut-off valve 7 and gas side When one of the shut-off valves 8 is closed, if the shut-off shut-off valve is operating normally, the refrigerant pressure on the suction side and the discharge side of the compressor 21 changes abruptly. If the valve is not operating normally, the refrigerant pressure on the suction side and the discharge side of the compressor 21 does not show a tendency to change rapidly. As described above, when one of the liquid-side shut-off valve 7 and the gas-side shut-off valve 8 in the open state is closed during the operation of the compressor 21, based on the change in the pressure value of the refrigerant at this time. It is possible to determine whether one of the liquid-side shut-off valve 7 and the gas-side shut-off valve 8 that has been closed is operating normally including the shut-off performance. Therefore, the shut-off valve inspection process described here is based on such a technical idea.

  Next, the shut-off valve inspection process will be described in detail with reference to FIGS. Here, FIG. 4 is a flowchart of the shut-off valve check process involving the operation of the compressor 21 in the cooling cycle state, and FIG. 5 is a flowchart of the shut-off valve check process involving the operation of the compressor 21 in the heating cycle state. It is. When an instruction for shut-off valve inspection processing is given to the system control unit 11 via the indoor operation unit 144 of the indoor control unit 40 or the outdoor operation unit 124 of the outdoor control unit 20, the shut-off valve inspection processing unit 148 of the indoor control unit 40. Thus, the following shut-off valve inspection process is executed. In addition, here, it is possible to select and perform either a shut-off valve check process by operating the compressor 21 in the cooling cycle state or a shut-off valve check process by operating the compressor 21 in the heating cycle state. It has become.

  First, the shut-off valve inspection process accompanied by the operation of the compressor 21 in the cooling cycle state will be described.

  In step ST1, the shut-off valve inspection processing unit 148 causes the outdoor heat exchanger 24 to function as a refrigerant radiator in a state in which the liquid-side shut-off valve 7 and the gas-side shut-off valve 8 are opened (cooling cycle state). ), The compressor 21 is operated, and then in step ST2, one of the liquid side shutoff valve 7 and the gas side shutoff valve 8 is closed. That is, an operation similar to the cooling operation in which the refrigerant circulates in the refrigerant circuit 10 in the cooling cycle state is performed, and then one of the liquid-side shut-off valve 7 and the gas-side shut-off valve 8 is closed so that the compressor 21 It tries to stop the circulation of the refrigerant while continuing the operation.

  Here, when the compressor 21 is operated in the cooling cycle state with both the liquid side shut-off valve 7 and the gas side shut-off valve 8 opened, the open liquid-side shut-off valve 7 and When one of the gas-side shut-off valves 8 is closed, the refrigerant pressure Ps (suction pressure Ps) on the suction side of the compressor 21 tends to rapidly decrease if the closed shut-off valve operates normally. As shown, the suction pressure Ps does not tend to decrease rapidly unless the shut-off shut-off valve is operating normally. Thus, in steps ST1 and ST2, as described above, when the compressor 21 is operating in the cooling cycle state, one of the opened liquid side shutoff valve 7 and gas side shutoff valve 8 is closed. Thus, as long as the shut-off valve that has been closed is operating normally, a state in which the suction pressure Ps tends to decrease rapidly is created.

  Then, the shut-off valve inspection processing unit 148 detects the refrigerant detected by the suction pressure sensor 35 when one of the liquid-side shut-off valve 7 and the gas-side shut-off valve 8 is closed in step ST3 after the processing of steps ST1 and ST2. Based on the change in the pressure value (suction pressure Ps), it is determined whether one of the closed liquid-side shut-off valve 7 and gas-side shut-off valve 8 is operating normally. Here, when one of the liquid-side shut-off valve 7 and the gas-side shut-off valve 8 is closed in step ST2 and the suction pressure Ps tends to decrease rapidly, the closed liquid-side shut-off valve 7 and It is determined that one of the gas side shut-off valves 8 is operating normally. Here, whether or not the suction pressure Ps has a tendency to rapidly decrease is determined, for example, by a decrease width ΔPs of the suction pressure Ps before and after performing the closing operation of one of the liquid side shutoff valve 7 and the gas side shutoff valve 8 in step ST2. Can be determined based on whether or not becomes equal to or greater than a predetermined decrease width ΔPss.

  If it is determined in step ST3 that one of the liquid-side shut-off valve 7 and the gas-side shut-off valve 8 that has been closed to satisfy the condition of the suction pressure Ps is operating normally, the step In ST4, the fact that one of the closed liquid-side shut-off valve 7 and gas-side shut-off valve 8 is operating normally is notified through a display on the indoor display unit 145 of the indoor control unit 40, and the above suction pressure. If it is determined that one of the liquid-side shut-off valve 7 and the gas-side shut-off valve 8 that has been closed without satisfying the condition of Ps is not operating normally, in step ST5, the liquid-side shut-off that has been closed is performed. The fact that one of the valve 7 and the gas side shutoff valve 8 is not operating normally is notified through a display on the indoor display unit 145 of the indoor control unit 40 or the like.

  In this way, the operation confirmation including the shutoff performance of one of the liquid side shutoff valve 7 and the gas side shutoff valve 8 can be reliably performed by the processing of steps ST1 to ST5.

  Then, the shut-off valve inspection processing unit 148 determines whether one of the closed liquid-side shut-off valve 7 and gas-side shut-off valve 8 is operating normally (that is, after the processing of steps ST1 to ST5). In step ST6, one of the liquid-side shut-off valve 7 and the gas-side shut-off valve that has been closed is opened, and then in step ST7, the other of the liquid-side shut-off valve 7 and the gas-side shut-off valve 8 is closed. . That is, after confirming the operation of one of the liquid side shutoff valve 7 and the gas side shutoff valve 8, both the liquid side shutoff valve 7 and the gas side shutoff valve 8 are opened to operate the compressor 21 in the cooling cycle state. , And the other of the liquid side shutoff valve 7 and the gas side shutoff valve 8 that have not been checked for operation is closed to stop the circulation of the refrigerant while continuing the operation of the compressor 21. It tries to.

  The shut-off valve inspection processing unit 148 then detects the refrigerant detected by the suction pressure sensor 35 when the other of the liquid-side shut-off valve 7 and the gas-side shut-off valve 8 is closed in step ST8 after the processing of steps ST6 and ST7. Based on the change in the pressure value (suction pressure Ps), it is determined whether or not the other of the closed liquid-side shut-off valve 7 and gas-side shut-off valve 8 is operating normally. Here, when the other closing operation of the liquid side shut-off valve 7 and the gas side shut-off valve 8 in step ST7 shows a tendency that the suction pressure Ps rapidly decreases, the closing operation is performed as in step ST3. It is determined that the other of the liquid side cutoff valve 7 and the gas side cutoff valve 8 is operating normally.

  If it is determined in step ST8 that the other of the liquid side shut-off valve 7 and the gas side shut-off valve 8 that has been closed to satisfy the condition of the suction pressure Ps is operating normally, step In ST9, the fact that the other one of the closed liquid-side shutoff valve 7 and gas-side shutoff valve 8 is operating normally is notified through a display on the indoor display unit 145 of the indoor control unit 40, etc. If it is determined that the other of the liquid-side shut-off valve 7 and the gas-side shut-off valve 8 that has been closed without satisfying the condition of Ps is not operating normally, in step ST10, the liquid-side shut-off that has been closed is performed. The fact that the other of the valve 7 and the gas side shut-off valve 8 is not operating normally is notified through a display on the indoor display unit 145 of the indoor control unit 40 or the like.

  As described above, by the processing of steps ST6 to ST10, the operation check including the other shutoff performance of the liquid side shutoff valve 7 and the gas side shutoff valve 8 can be reliably performed. That is, the operation confirmation including the shutoff performance of the liquid side shutoff valve 7 and the gas side shutoff valve 8 can be reliably performed by the processing of steps ST1 to ST10.

  Next, the shut-off valve inspection process accompanied by the operation of the compressor 21 in the heating cycle state will be described.

  In step ST11, the shutoff valve inspection processing unit 148 causes the outdoor heat exchanger 24 to function as a refrigerant evaporator in a state in which the liquid side shutoff valve 7 and the gas side shutoff valve 8 are opened (heating cycle state). ), The compressor 21 is operated, and then in step ST12, one of the liquid side shutoff valve 7 and the gas side shutoff valve 8 is closed. That is, an operation similar to the heating operation in which the refrigerant circulates in the refrigerant circuit 10 in a heating cycle state is performed, and then one of the liquid-side shut-off valve 7 and the gas-side shut-off valve 8 is closed, whereby the compressor 21 It tries to stop the circulation of the refrigerant while continuing the operation.

  Here, when the compressor 21 is operated in the heating cycle with both the liquid-side shut-off valve 7 and the gas-side shut-off valve 8 being opened, the open-side liquid-side shut-off valve 7 and If one of the gas side shutoff valves 8 is closed, the refrigerant pressure Pd (discharge pressure Pd) on the discharge side of the compressor 21 tends to increase rapidly if the shut off shut valve operates normally. As shown, if the shut-off shut-off valve is not operating normally, the discharge pressure Pd does not tend to increase rapidly. Thus, in steps ST11 and ST12, as described above, when the compressor 21 is operating in the heating cycle state, one of the opened liquid side shutoff valve 7 and gas side shutoff valve 8 is closed. By doing so, as long as the shut-off valve that has been closed is operating normally, a state in which the discharge pressure Pd tends to increase rapidly is created.

  The shut-off valve inspection processing unit 148 then detects the refrigerant detected by the discharge pressure sensor 36 when one of the liquid-side shut-off valve 7 and the gas-side shut-off valve 8 is closed in step ST13 after the processing in steps ST11 and ST12. Based on the change in the pressure value (discharge pressure Pd), it is determined whether one of the closed liquid-side shut-off valve 7 and gas-side shut-off valve 8 is operating normally. Here, when one of the liquid-side shut-off valve 7 and the gas-side shut-off valve 8 is closed in step ST12 and the discharge pressure Pd tends to increase rapidly, the closed liquid-side shut-off valve 7 and It is determined that one of the gas side shut-off valves 8 is operating normally. Here, whether or not the discharge pressure Pd has shown a tendency to increase rapidly is determined, for example, by an increase width ΔPd of the discharge pressure Pd before and after performing the closing operation of one of the liquid-side cutoff valve 7 and the gas-side cutoff valve 8 in step ST12. Can be determined based on whether or not has reached a predetermined increase width ΔPds or more.

  If it is determined in step ST13 that one of the liquid-side shut-off valve 7 and the gas-side shut-off valve 8 that has been closed to satisfy the condition of the discharge pressure Pd is operating normally, the step In ST14, the fact that one of the closed liquid-side shut-off valve 7 and gas-side shut-off valve 8 is operating normally is notified through a display on the indoor display unit 145 of the indoor control unit 40, and the above discharge pressure. If it is determined that one of the liquid-side shut-off valve 7 and the gas-side shut-off valve 8 that is closed without satisfying the Pd condition is not operating normally, in step ST15, the liquid-side shut-off that has been closed is operated. The fact that one of the valve 7 and the gas side shutoff valve 8 is not operating normally is notified through a display on the indoor display unit 145 of the indoor control unit 40 or the like.

  As described above, by the processing of steps ST11 to ST15, it is possible to reliably perform an operation check including the shutoff performance of one of the liquid side shutoff valve 7 and the gas side shutoff valve 8.

  Then, the shut-off valve inspection processing unit 148 determines whether one of the closed liquid-side shut-off valve 7 and gas-side shut-off valve 8 is operating normally (that is, after the processing of steps ST11 to ST15). In step ST16, one of the closed liquid-side cutoff valve 7 and the gas-side cutoff valve is opened, and then in step ST17, the other of the liquid-side cutoff valve 7 and the gas-side cutoff valve 8 is closed. . That is, after confirming the operation of one of the liquid side shutoff valve 7 and the gas side shutoff valve 8, both the liquid side shutoff valve 7 and the gas side shutoff valve 8 are opened to operate the compressor 21 in the heating cycle state. , And the other of the liquid side shutoff valve 7 and the gas side shutoff valve 8 that have not been checked for operation is closed to stop the circulation of the refrigerant while continuing the operation of the compressor 21. It tries to.

  The shut-off valve inspection processing unit 148 then detects the refrigerant detected by the discharge pressure sensor 36 when the other of the liquid-side shut-off valve 7 and the gas-side shut-off valve 8 is closed in step ST18 after the processing in steps ST16 and ST17. Based on the change of the pressure value (discharge pressure Pd), it is determined whether or not the other of the closed liquid-side shut-off valve 7 and gas-side shut-off valve 8 is operating normally. Here, when the other closing operation of the liquid side shutoff valve 7 and the gas side shutoff valve 8 in step ST17 showed a tendency for the discharge pressure Pd to increase rapidly, the closing operation was performed as in step ST13. It is determined that the other of the liquid side cutoff valve 7 and the gas side cutoff valve 8 is operating normally.

  If it is determined in step ST18 that the other of the liquid-side shut-off valve 7 and the gas-side shut-off valve 8 that has been closed to satisfy the condition of the discharge pressure Pd is operating normally, the step In ST19, the fact that the other one of the closed liquid-side shutoff valve 7 and gas-side shutoff valve 8 is operating normally is notified through a display on the indoor display unit 145 of the indoor control unit 40, etc. If it is determined that the other of the liquid-side shut-off valve 7 and the gas-side shut-off valve 8 that have been closed without satisfying the Pd condition is not operating normally, in step ST20, the liquid-side shut-off that has been closed is performed. The fact that the other of the valve 7 and the gas side shut-off valve 8 is not operating normally is notified through a display on the indoor display unit 145 of the indoor control unit 40 or the like.

  As described above, by the processes in steps ST16 to ST20, the operation check including the other shutoff performance of the liquid side shutoff valve 7 and the gas side shutoff valve 8 can be reliably performed. That is, the operation confirmation including the shutoff performance of the liquid side shutoff valve 7 and the gas side shutoff valve 8 can be reliably performed by the processing of steps ST11 to ST20.

(3) Modifications In order to ensure that refrigerant leakage processing such as closing of the shut-off valves 7 and 8 when refrigerant leakage is detected is performed during periodic inspection of the air conditioning system 1 or the like, It is desirable not only to confirm the operation of the liquid side shutoff valve 7 and the gas side shutoff valve 8, but also to confirm the communication connection between the system control unit 11 and the refrigerant leakage detection device 9.

  For this reason, a signal indicating the presence or absence of refrigerant leakage is simulated from the refrigerant leakage detection device 9, and a simulated signal indicating the presence or absence of the refrigerant is input to the system control unit 11. It is conceivable to perform the shut-off valve inspection process of the above-described embodiment by performing the opening / closing operation of the gas-side shut-off valve 8.

  However, when the shut-off valve inspection process is performed by simulating the opening / closing operation of the liquid-side shut-off valve 7 and the gas-side shut-off valve 8 and indicating the presence or absence of refrigerant leakage output from the refrigerant leak detection device 9 The system controller 11 needs to be able to distinguish whether the signal output from the refrigerant leakage detection device 9 is a simulated input or a signal indicating the presence or absence of actual refrigerant leakage. . This is because when the signal indicating that the refrigerant has leaked is input from the refrigerant leak detection device 9, the system control unit 11 determines that the refrigerant has actually leaked, and shuts off the liquid side. This is because the valve 7 and the gas-side shut-off valve 8 are closed and operations necessary for the shut-off valve inspection process such as operating the compressor 21 in the cooling cycle state or the heating cycle state cannot be performed. That is, when a signal indicating that a refrigerant leak is generated from the refrigerant leakage detection device 9 is input to the system control unit 11, the refrigerant of the system control unit 11 is used regardless of whether the signal is a simulated input or not. The leakage processing unit 147 performs refrigerant leakage processing (processing for closing the liquid side cutoff valve 7 and the gas side cutoff valve 8 to stop the compressor 21), and the cutoff valve inspection processing unit 148 of the system control unit 11 is performed. This means that the shut-off valve inspection process cannot be performed.

  Therefore, here, as shown in FIG. 6, in the shut-off valve inspection process, a signal indicating the presence or absence of refrigerant leakage output from the refrigerant leak detection device 9 is simulated and input to the system control unit 11 to simulate the liquid side. A simulated input permission unit 149 for permitting the opening / closing operation of the shut-off valve 7 and the gas-side shut-off valve 8 is provided in the system control unit 11 (here, the indoor CPU 141 of the indoor control unit 40). Prior to performing the shut-off valve inspection process, the liquid side is obtained by simulating input of a signal indicating the presence or absence of refrigerant leakage output from the refrigerant leakage detection device 9 through the indoor operation unit 144 of the indoor control unit 40 or the like. By inputting to the simulated input permission unit 149 that the shut-off valve 7 and the gas-side shut-off valve 8 are opened and closed, the refrigerant leak processing by the refrigerant leak processing unit 147 is prevented from being performed, and the shut-off valve inspection is performed. The processing unit 148 permits the shut-off valve inspection process. By doing in this way, the system control part 11 will judge that the leakage of the refrigerant | coolant has really generate | occur | produced by the simulated input of the signal which shows the presence or absence of the leakage of the refrigerant | coolant output from the refrigerant | coolant leak detection apparatus 9. Therefore, it is possible to perform an operation necessary for the shut-off valve check process such as operating the compressor 21 in the cooling cycle state or the heating cycle state.

  In this case, the shutoff valve inspection process can be performed by inputting a signal indicating the presence or absence of refrigerant leakage output from the refrigerant leakage detection device 9 to the system control unit 11 in a simulated manner. The operation of the liquid side shutoff valve 7 and the gas side shutoff valve 8 can be confirmed along with the confirmation of the communication connection between the unit 11 and the refrigerant leak detection device 9.

Second Embodiment
In the first embodiment and the modification thereof, one indoor unit 4 is connected to the outdoor unit 2 via the refrigerant communication pipes 5 and 6, and the liquid side shut-off valve 7 and the The structure (refer FIGS. 1-3, FIG. 6) by which the gas side cutoff valve 8 was provided in the liquid refrigerant pipe 50 and the gas refrigerant pipe 60 is employ | adopted.

  However, a plurality of indoor units are connected to the outdoor unit 2 via the refrigerant communication pipes 5 and 6, and a liquid side shutoff valve and a gas side shutoff valve are connected to the liquid refrigerant pipe 50 and the gas refrigerant pipe 60 corresponding to each indoor unit. The provided configuration may be adopted.

  As such a configuration, for example, as shown in FIGS. 7 to 9, a plurality (here, two) of indoor units 4 a and 4 b are connected to the outdoor unit 2 via the refrigerant communication pipes 5 and 6. There is a configuration in which the liquid side shutoff valves 7a and 7b and the gas side shutoff valves 8a and 8b are provided in the liquid refrigerant pipe 50 and the gas refrigerant pipe 60 corresponding to the indoor units 4a and 4b.

(1) Configuration Next, regarding the configuration of the air conditioning system 1 having a plurality of indoor units 4a, 4b, one indoor unit 4 of the first embodiment is connected to the outdoor unit 2 via the refrigerant communication tubes 5, 6. The description will focus on the differences from the configuration.

  Specifically, the air conditioning system 1 having a plurality of indoor units 4a and 4b is a system that cools and heats a room such as a building by a vapor compression refrigeration cycle, as in the first embodiment. The air conditioning system 1 mainly includes a vapor compression refrigerant circuit 10 configured by connecting an outdoor unit 2 and indoor units 4a and 4b via a liquid refrigerant communication tube 5 and a gas refrigerant communication tube 6. Yes. The refrigerant circuit 10 is filled with a refrigerant having a slight flammability such as R32 or a refrigerant having a strong flammability such as R290 as the refrigerant.

  The outdoor unit 2 is installed outdoors and mainly includes a compressor 21 and an outdoor heat exchanger 24 as in the first embodiment. Here, since the structure of the outdoor unit 2 is the same as that of the outdoor unit 2 of 1st Embodiment, it attaches | subjects the same code | symbol as the thing of 1st Embodiment, and abbreviate | omits description here.

  The indoor unit 4a is installed in the room A and has an indoor heat exchanger 42a, and the indoor unit 4b is installed in the room B and has an indoor heat exchanger 42b. Here, since the configuration of the indoor units 4a and 4b is basically the same as that of the indoor unit 4 of the first embodiment, the subscripts “a” and “b” are added to the same reference numerals as those of the first embodiment. Thus, the description is omitted here. However, here, unlike the first embodiment, in each indoor unit 4a, 4b, the indoor liquid refrigerant pipe 43a of the indoor unit 4a is connected to the indoor liquid refrigerant pipe 43a so that the cooling operation and the heating operation can be performed individually. An expansion valve 41a is provided, and the indoor expansion valve 41b is provided in the indoor liquid refrigerant pipe 43b of the indoor unit 4b. These indoor expansion valves 41a and 41b are electric expansion valves capable of opening degree control.

  Further, here, the liquid refrigerant pipe 50 and the gas refrigerant communication pipe 6 from the liquid side end of the outdoor unit 2 including the liquid refrigerant communication pipe 5 to the liquid side ends of the indoor heat exchangers 42a and 42b are included. Liquid side shut-off valves 7a, 7b that are closed when refrigerant leakage is detected in the gas refrigerant pipe 60 from the gas side end of the outdoor unit 2 to the gas side ends of the indoor heat exchangers 42a, 42b. Gas side shut-off valves 8a and 8b are provided. Here, the liquid side shut-off valve 7 a is provided in the liquid refrigerant branch pipe 50 a that branches in correspondence with the indoor unit 4 a in the liquid refrigerant pipe 50, and the liquid side shut-off valve 7 b is provided in the liquid refrigerant pipe 50. Of these, the liquid refrigerant branch pipe 50b is branched corresponding to the indoor unit 4b. Further, the gas side shut-off valve 8 a is provided in the gas refrigerant branch pipe 60 a that is branched corresponding to the indoor unit 4 a in the gas refrigerant pipe 60, and the gas side shut-off valve 8 b is provided in the gas refrigerant pipe 60. The gas refrigerant branch pipe 60b is branched corresponding to the indoor unit 4b. Since the configuration of these shutoff valves 7a, 7b, 8a, 8b is the same as that of the shutoff valves 7, 8 of the first embodiment, the subscripts “a” and “b” are added to the same reference numerals as those of the first embodiment. A description thereof will be omitted here.

  Also, here, in order to detect the presence or absence of refrigerant leakage on the indoor unit 4a side, the refrigerant leakage detection device 9a is provided in the room A, and in order to detect the presence or absence of refrigerant leakage on the indoor unit 4b side. The refrigerant leakage detection device 9b is provided in the room B. Here, since the configuration of the refrigerant leak detection devices 9a and 9b is the same as that of the refrigerant leak detection device 9 of the first embodiment, subscripts “a” and “b” are added to the same reference numerals as those of the first embodiment. Thus, the description is omitted here.

  And here, the system control part 11 which controls the component apparatus containing the liquid side cutoff valves 7a and 7b and the gas side cutoff valves 8a and 8b is provided. The system control unit 11 controls the outdoor control unit 20 that controls the component devices of the outdoor unit 2, the indoor control units 40a and 40b that control the component devices of the indoor units 4a and 4b, and the liquid side shut-off valves 7a and 7b. The liquid side cutoff control units 70a and 70b and the gas side cutoff control units 80a and 80b for controlling the gas side cutoff valves 8a and 8b are connected via a communication line. The outdoor control unit 20 is provided in the outdoor unit 2. The indoor control units 40a and 40b are provided in the indoor units 4a and 4b. The liquid side cutoff control units 70a and 70b are provided in the liquid side cutoff valves 7a and 7b, and the gas side cutoff control units 80a and 80b are provided in the gas side cutoff valves 8a and 8b. The system control unit 11 is also connected to refrigerant leakage detection control units 90a and 90b that control the refrigerant leakage detection devices 9a and 9b. The refrigerant leakage detection control units 90a and 90b are provided in the refrigerant leakage detection devices 9a and 9b. Here, since the outdoor control part 20 is the same as the outdoor control part 20 of 1st Embodiment, it attaches | subjects the same code | symbol as the thing of 1st Embodiment, and abbreviate | omits description here. The control units 40a, 40b, 70a, 70b, 80a, 80b, 90a, and 90b are the same as the control units 40, 70, 80, and 90 of the first embodiment, and therefore the same reference numerals as those of the first embodiment. The subscripts “a” and “b” are attached to and the description is omitted here.

(2) Operation-Normal operation-
Here, as in the first embodiment, the cooling operation and the heating operation are performed as the normal operation. Specifically, when an instruction for cooling operation or heating operation is given to the system control unit 11 via the indoor operation units 144a, 144b of the indoor control units 40a, 40b, the normal operation processing unit 146a of the indoor CPUs 141a, 141b, By 146b, basically the same cooling operation or heating operation as in the first embodiment is executed. However, the indoor units 4a and 4b are provided with indoor expansion valves 41a and 41b, and the only difference is that the opening degree control is performed in the cooling operation and the heating operation.

-Refrigerant leakage treatment-
In the above normal operation, when refrigerant leakage is detected, the liquid side shutoff valves 7a and 7b and the gas side shutoff valves 8a and 8b are closed in order to reduce the amount of refrigerant leaked into the room. There is a need. Therefore, a signal indicating that a refrigerant leak output from the refrigerant leakage detection devices 9a and 9b (refrigerant leakage detection control units 90a and 90b) is input to the system control unit 11 (indoor control units 40a and 40b). Then, the refrigerant leakage processing similar to that of the first embodiment is executed by the refrigerant leakage processing units 147a and 147b of the indoor CPUs 141a and 141b.

  Specifically, the liquid side shutoff valves 7a and 7b and the gas side shutoff valves 8a and 8b are closed to eliminate the flow of refrigerant from the outdoor unit 2 to the indoor units 4a and 4b. The compressor 21 is also stopped. Thereby, the leakage amount of the refrigerant | coolant to room | chamber A and B can be reduced, and generation | occurrence | production of the ignition accident in a room | chamber interior can be suppressed here so that the combustible refrigerant | coolant may not exceed combustible density | concentration.

-Check valve check process-
Here, basically, as in the first embodiment, the liquid side shut-off valves 7a and 7b and the liquid side shut-off valves 7a and 7b and the gas-side shut-off valves 8a and 8b are checked as the shut-off valve check process for confirming the operation. The compressor 21 is operated in a state where the gas side shut-off valves 8a and 8b are opened, and then the refrigerant when the liquid side shut-off valves 7a and 7b and the gas side shut-off valves 8a and 8b are closed is displayed. Based on the change in the pressure value, it is determined whether or not the shut-off shut-off valve is operating normally.

  However, in the air conditioning system 1 having a plurality of indoor units 4a and 4b, liquid-side cutoff valves 7a and 7b and gas-side cutoff valves 8a and 8b corresponding to the indoor units 4a and 4b are provided, and a plurality of liquid-side cutoff valves 7a are provided. , 7b and gas side shut-off valves 8a and 8b, when the shut-off valve inspection process is performed at the same time, the pressure value change due to the closing operation of the plurality of liquid side shut-off valves 7a and 7b and gas side shut-off valves 8a and 8b simultaneously There is a problem that it is not possible to distinguish which shutoff valve is operating normally (or which shutoff valve is not operating normally).

  Therefore, here, for one indoor unit (for example, the indoor unit 4a) among the plurality of indoor units 4a and 4b, the corresponding liquid side shutoff valve 7a and gas side shutoff valve 8a are subjected to shutoff valve inspection processing. On the other hand, among the plurality of indoor units 4a and 4b, the operation of the indoor unit (for example, the indoor unit 4b) that is not the target of the shut-off valve inspection process is stopped. For this reason, it is possible to determine whether or not the operation is normally performed after distinguishing whether there is a change in the pressure value due to the closing operation of the shut-off valve from the shut-off valve that is the target of the shut-off valve inspection process. .

  Specifically, the shut-off valve inspection process basically follows the processes of steps ST1 to ST10 and steps ST11 to ST20 shown in the flowcharts of FIGS. This is executed for the liquid side shutoff valve and the gas side shutoff valve corresponding to the indoor unit to be inspected. However, at this time, the indoor units that are not the inspection target are stopped by closing the corresponding indoor expansion valves as shown in steps ST1 and ST6 and steps ST11 and ST16. In this way, for one indoor unit among the plurality of indoor units 4a and 4b, the plurality of indoor units 4a and 4b are subjected to the shut-off valve inspection process for the corresponding liquid-side shut-off valve and gas-side shut-off valve. Among them, the operation is stopped for the indoor units that are not the target of the shut-off valve inspection process. For this reason, it operates normally after distinguishing whether there is a change in the pressure value (suction pressure Ps or discharge pressure Pd) due to closing operation of the shut-off valve from being due to the shut-off valve subject to the shut-off valve inspection process. You can judge whether or not.

  Thereby, even if it is the structure which provided the liquid side shut-off valve 7a, 7b and gas side shut-off valve 8a, 8b corresponding to each of several indoor unit 4a, 4b here, several shut-off valve 7a, 7b, It is possible to determine whether or not each of the shut-off valves 7a, 7b, 8a, and 8b is operating normally by sequentially performing the operation check including the shut-off performance for 8a and 8b.

(3) Modification 1
Also in the above embodiment, as in the modification of the first embodiment, as shown in FIG. 12, a signal indicating the presence or absence of refrigerant leakage output from the refrigerant leakage detection devices 9 a and 9 b is simulated in the system control unit 11. System input unit 149a and 149b for permitting the liquid side shut-off valves 7a and 7b and the gas side shut-off valves 8a and 8b to be opened and closed by the system input. You may make it provide in indoor CPU141a, 141b) of part 40a, 40b.

(4) Modification 2
In the said embodiment and the modification 1, the liquid side shutoff valves 7a and 7b corresponding to each indoor unit 4a and 4b are provided in the liquid refrigerant pipe 50 (50a and 50b). However, here, since the liquid expansion pipes 50 (50a, 50b) are provided with indoor expansion valves 41a, 41b corresponding to the indoor units 4a, 4b, the indoor expansion valves 41a, 41b are closed. When the shut-off performance (valve leakage amount in the closed state, etc.) satisfies the shut-off performance required by the shut-off valve, the indoor expansion valves 41a and 41b may be used also as the liquid-side shut-off valves 7a and 7b.

<Other embodiments>
In the said 1st and 2nd embodiment and these modifications, although the structure which can be switched and performed between air_conditionaing | cooling operation and heating operation is employ | adopted, it is not limited to this. For example, other configurations such as a configuration dedicated to cooling without the switching mechanism 23 may be used.

  Moreover, in the said 1st and 2nd embodiment and these modifications, although the refrigerant | coolant leak detection apparatus 9, 9a, 9b is provided indoors, it is not limited to this. For example, you may be provided in other places, such as in indoor unit 4, 4a, 4b.

  The present invention includes a refrigerant circuit configured by connecting an outdoor unit having a compressor and an outdoor heat exchanger and an indoor unit having an indoor heat exchanger via a refrigerant communication pipe, and the liquid side of the outdoor unit Leakage of refrigerant is detected from the liquid refrigerant pipe from the end to the liquid side end of the indoor heat exchanger and the gas refrigerant pipe from the gas side end of the outdoor unit to the gas side end of the indoor heat exchanger The present invention can be widely applied to an air conditioning system provided with a shut-off valve that is closed when the operation is performed.

DESCRIPTION OF SYMBOLS 1 Air conditioning system 2 Outdoor unit 4, 4a, 4b Indoor unit 5 Liquid refrigerant communication pipe 6 Gas refrigerant communication pipe 7, 7a, 7b Liquid side shutoff valve 8, 8a, 8b Gas side shutoff valve 9, 9a, 9b Refrigerant leak detection Device 10 Refrigerant circuit 11 System controller 21 Compressor 24 Outdoor heat exchanger 35 Suction pressure sensor 36 Discharge pressure sensor 42, 42a, 42b Indoor heat exchanger 50 Liquid refrigerant pipe 60 Gas refrigerant pipe 149, 149a, 149b Simulation input permission section

JP 2013-19621 A

Claims (6)

An outdoor unit (2) having a compressor (21) and an outdoor heat exchanger (24) and an indoor unit (4, 4a, 4b) having an indoor heat exchanger (42, 42a, 42b) are connected to a liquid refrigerant communication pipe ( 5) and a refrigerant circuit (10) configured by connecting via a gas refrigerant communication pipe (6), and the indoor heat exchanger from the liquid side end of the outdoor unit including the liquid refrigerant communication pipe A liquid refrigerant pipe (50) up to the liquid side end of the gas, and a gas refrigerant pipe (from the gas side end of the outdoor unit including the gas refrigerant communication pipe to the gas side end of the indoor heat exchanger ( 60) In an air conditioning system provided with a liquid side shut-off valve (7, 7a, 7b) and a gas side shut-off valve (8, 8a, 8b) which are closed when refrigerant leakage is detected.
The outdoor unit is provided with a suction pressure sensor (35) for detecting the pressure of the refrigerant on the suction side of the compressor,
The system control unit (11) that controls the components including the liquid side shutoff valve and the gas side shutoff valve may perform a shutoff valve check process for confirming the operation of the liquid side shutoff valve and the gas side shutoff valve. Is possible,
In the shut-off valve inspection process, the compressor is operated in a state where the outdoor heat exchanger functions as a refrigerant radiator in a state where the liquid-side shut-off valve and the gas-side shut-off valve are opened. The liquid-side shut-off valve that has been closed based on a change in the pressure value of the refrigerant detected by the suction pressure sensor when one of the liquid-side shut-off valve and the gas-side shut-off valve is closed. Determine whether one of the gas side shut-off valves is operating normally,
Air conditioning system (1). In the shut-off valve check process, it is determined whether one of the closed liquid-side shut-off valves (7, 7a, 7b) and the gas-side shut-off valves (8, 8a, 8b) is operating normally. Later, one of the liquid-side shut-off valve and the gas-side shut-off valve that has been closed is opened, and then the other of the liquid-side shut-off valve and the gas-side shut-off valve is closed. Based on a change in the pressure value of the refrigerant detected by the sensor (35), it is determined whether the other of the liquid-side shut-off valve and the gas-side shut-off valve that has been closed is operating normally.
The air conditioning system (1) according to claim 1. An outdoor unit (2) having a compressor (21) and an outdoor heat exchanger (24) and an indoor unit (4, 4a, 4b) having an indoor heat exchanger (42, 42a, 42b) are connected to a liquid refrigerant communication pipe ( 5) and a refrigerant circuit (10) configured by connecting via a gas refrigerant communication pipe (6), and the indoor heat exchanger from the liquid side end of the outdoor unit including the liquid refrigerant communication pipe A liquid refrigerant pipe (50) up to the liquid side end of the gas, and a gas refrigerant pipe (from the gas side end of the outdoor unit including the gas refrigerant communication pipe to the gas side end of the indoor heat exchanger ( 60) In an air conditioning system provided with a liquid side shut-off valve (7, 7a, 7b) and a gas side shut-off valve (8, 8a, 8b) which are closed when refrigerant leakage is detected.
The outdoor unit is provided with a discharge pressure sensor (36) for detecting the pressure of the refrigerant on the discharge side of the compressor,
The system control unit (11) that controls the components including the liquid side shutoff valve and the gas side shutoff valve may perform a shutoff valve check process for confirming the operation of the liquid side shutoff valve and the gas side shutoff valve. Is possible,
In the shut-off valve inspection process, the compressor is operated in a state where the outdoor heat exchanger functions as the refrigerant evaporator in a state where the liquid-side shut-off valve and the gas-side shut-off valve are opened. The liquid-side shut-off valve that has been closed based on a change in the pressure value of the refrigerant that is detected by the discharge pressure sensor when one of the liquid-side shut-off valve and the gas-side shut-off valve is closed. Determine whether one of the gas side shut-off valves is operating normally,
Air conditioning system (1). In the shut-off valve check process, it is determined whether one of the closed liquid-side shut-off valves (7, 7a, 7b) and the gas-side shut-off valves (8, 8a, 8b) is operating normally. Thereafter, one of the liquid-side shut-off valve and the gas-side shut-off valve that has been closed is opened, and then the other of the liquid-side shut-off valve and the gas-side shut-off valve is closed. Based on a change in the pressure value of the refrigerant detected by the sensor (36), it is determined whether the other of the liquid-side shut-off valve and the gas-side shut-off valve that has been closed is operating normally.
The air conditioning system (1) according to claim 3. There are a plurality of the indoor units (4a, 4b),
The liquid side shutoff valves (7a, 7b) and the gas side shutoff valves (8a, 8b) are provided in the liquid refrigerant pipe (50) and the gas refrigerant pipe (60) so as to correspond to the indoor units. And
The system control unit (11) is configured to perform the shut-off valve check process on the corresponding liquid-side shut-off valve and the gas-side shut-off valve for one indoor unit among the plurality of indoor units, For the indoor units that are not subject to the shut-off valve inspection process among the indoor units, the operation is stopped.
The air conditioning system (1) according to any one of claims 1 to 4. The system controller (11) is connected to a refrigerant leakage detection device (9, 9a, 9b) that detects the presence or absence of leakage of the refrigerant,
In the shut-off valve inspection process, the system control unit is configured to input a signal indicating whether or not the refrigerant is leaked, which is output from the refrigerant leak detection device, to the liquid-side shut-off valve ( 7, 7a, 7b) and a simulated input permission unit (149, 149a, 149b) for allowing the gas side shut-off valve (8, 8a, 8b) to be opened and closed.
The air conditioning system (1) according to any one of claims 1 to 5.

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