Patent ID: 12235029

DETAILED DESCRIPTION

Embodiment is described below with reference to the drawings. In the drawings below, size relationships among components may differ from real ones.

Embodiment

FIG.1is a schematic diagram illustrating an example of an air-conditioning system according to Embodiment. An air-conditioning system100according to Embodiment includes an outdoor unit1, a plurality of indoor units2, and one or more stop valve units3. The outdoor unit1, the plurality of indoor units2, and the stop valve units3are connected together with a refrigerant pipe7, and the refrigerant pipe7allows refrigerant to pass through its inside. Therefore, the refrigerant circulates through the outdoor unit1and the indoor units2. Such a circuit in which the refrigerant circulates is described as a refrigerant circuit4.

The refrigerant is charged into the outdoor unit1. Depending on the number of indoor units2connected to the outdoor unit1, the length of the refrigerant pipe7, and other factors, the refrigerant may be further added. Thus, the refrigerant circuit4may be filled with the refrigerant that has the volume larger than or equal to the volume of the refrigerant charged into the outdoor unit1.

Examples of the refrigerant in Embodiment may include refrigerant of HFO-1234yf alone, refrigerant of a mixture including HFO-1234yf, and hydrocarbon-based refrigerant, such as propane.

The outdoor unit1includes a compressor10, a flow switching device11, an outdoor heat exchanger12, an outdoor air-sending device13, and an outdoor flow control valve14. The compressor10, the flow switching device11, the outdoor heat exchanger12, and the outdoor flow control valve14are connected in sequence by the refrigerant pipe7.

The compressor10is configured to compress refrigerant sucked from a suction port and discharge it as high-temperature and high-pressure gas refrigerant from a discharge port. The flow switching device11may include, for example, a four-way valve and is configured to switch directions of a flow of the refrigerant. By switching the flows of the refrigerant by use of the flow switching device11, the operation is switched between cooling and heating. InFIG.1, the solid line segments in the flow switching device11indicate flows of the refrigerant in cooling operation. The broken line segments indicate flows of the refrigerant in heating operation. Similarly, inFIG.1, the arrows expressed by the solid lines indicate directions in which the refrigerant flows in cooling operation, and the arrows expressed by the broken lines indicate directions in which the refrigerant flows in heating operation.

The outdoor heat exchanger12is configured to exchange heat between the refrigerant and outdoor air. The outdoor heat exchanger12serves as a condenser for the refrigerant in cooling operation and serves as an evaporator for the refrigerant in heating operation. The outdoor air-sending device13includes a propeller fan drivable by a driving source, such as a fan motor, which is not illustrated, and is configured to guide the outdoor air to the outdoor heat exchanger12inside the outdoor unit1and to send air of which heat has been exchanged with the refrigerant to the outside.

The outdoor flow control valve14is also called an expansion valve and is configured to adjust the flow rate of the refrigerant circulating between the outdoor unit1and the indoor units2by changes in its opening degree and configured to decompress the refrigerant compressed in the compressor10. In Embodiment, the opening degree of the outdoor flow control valve14is adjusted depending on the operation status of the indoor units2. The outdoor flow control valve14may be disposed in the stop valve units3, which are described below, in place of in the outdoor unit1. Alternatively, the outdoor flow control valve14may be included in each of the outdoor unit1and the stop valve units3.

Each of the indoor units2includes an indoor heat exchanger20, an indoor air-sending device21, an indoor flow control valve22, a notification unit23, and an indoor control unit24. The notification unit23may be included in a remote controller, which is not illustrated, for the indoor unit2.

The indoor heat exchanger20is configured to exchange heat between the refrigerant from the outdoor unit1and air inside the room. The indoor heat exchanger20is configured to cause heat exchange between the refrigerant and the air sent from the inside of the room into the indoor unit2by the indoor air-sending device21.

The indoor air-sending device21includes a propeller fan drivable by, for example, a fan motor, which is not illustrated, and is configured to guide the air inside the room to the indoor heat exchanger20inside the indoor unit2and to send air of which heat has been exchanged with the refrigerant into the room. Like the outdoor flow control valve14, the indoor flow control valve22is also called an expansion valve and is configured to adjust the flow rate of the refrigerant circulating between the outdoor unit1and the indoor unit2by changes in its opening degree. The notification unit23is configured to provide notification in accordance with an instruction from the indoor control unit24, which is described below, in the case where the refrigerant leaks or in other cases.

The indoor control unit24is configured to control the indoor air-sending device21, the indoor flow control valve22, the notification unit23, and other elements. The indoor control unit24is configured to cause the outdoor unit1, the indoor unit2, and other elements to perform an air-conditioning action desired by a user in accordance with an instruction from a remote controller, which is not illustrated. In the description below, a signal transmitted by the indoor control unit24to the outdoor unit1and other components in the indoor unit2including the indoor control unit24to cause performing the air-conditioning action desired by the user is described as a control signal.

The stop valve unit3in Embodiment is a unit disposed in the refrigerant circuit4including each of the one or more indoor units2inside the same room. The stop valve unit3is disposed between the outdoor unit1and the one or more indoor units2in the refrigerant circuit4.

The stop valve unit3includes a plurality of stop valves30and an information processor31. The stop valve unit3in Embodiment houses the plurality of stop valves30and the information processor31inside its casing.

Each of the stop valves30is disposed in the refrigerant circuit4between the outdoor unit1and the indoor unit2. The stop valve30is configured to allow passage of the refrigerant through the refrigerant circuit4between the outdoor unit1and the indoor unit2by its opening action. The stop valve30is configured to stop the passage of the refrigerant through the refrigerant circuit4between the outdoor unit1and the indoor unit2by its closing action. The stop valve unit3in Embodiment includes the plurality of stop valves30disposed between the outdoor unit1and the one or more indoor units2inside a single room. The stop valve unit3may include the plurality of stop valves30disposed between the outdoor unit1and the plurality of indoor units2inside a plurality of rooms.

The information processor31is configured to exchange data with one or more refrigerant leak sensors5. The one or more refrigerant leak sensors5are disposed in the same room as the room of the one or more indoor units2connected to the stop valve unit3. The information processor31is configured to communicate with the indoor control unit24in each of the one or more indoor units2and to communicate with the outdoor unit1. The refrigerant leak sensors5may be included in the stop valve unit3. In this case, the stop valve unit3is placed in the same room as the room of the one or more indoor units2. In Embodiment, the indoor units2and the refrigerant leak sensors5placed inside a single room and the stop valves30disposed between these indoor units2and the outdoor unit1are combined in a single group. In Embodiment, the stop valves30in the single group are housed in the stop valve unit3.

The information processor31may be configured to communicate with each of the one or more refrigerant leak sensors5through a wire or wirelessly. In Embodiment, the information processor31is configured to communicate with the indoor control units24and the outdoor unit1wirelessly, and they may be configured to communicate with each other through a wire.

Each of the refrigerant leak sensors5is a sensor configured to detect the occurrence of a phenomenon where the refrigerant leaks from the refrigerant circuit4when such a phenomenon occurs. Examples of the refrigerant leak sensor5may include sensors of the oxygen concentration type, the combustible gas detection type, and other types.

When the refrigerant leak sensor5detects a leak of the refrigerant, the information processor31is configured to receive a signal indicating the leak of the refrigerant from the refrigerant leak sensor5. When receiving the signal, the information processor31is configured to transmit a signal to the plurality of stop valves30in the stop valve unit3, the outdoor unit1, and the one or more indoor units2connected to the stop valve unit3, and the signal requests an action programmed to be performed when the refrigerant leaks. In the description below, the signal requesting the predetermined action for the case where the leak of the refrigerant occurs may be described as a request signal. When receiving the signal indicating the leak of the refrigerant from at least one refrigerant leak sensor5, the information processor31is configured to transmit the request signal to all of the stop valves30in the stop valve unit3, all of the indoor units2connected to the stop valve unit3, and the outdoor unit1.

In the case where the single stop valve unit3includes the plurality of stop valves30disposed between the outdoor unit1and the plurality of indoor units2inside the plurality of rooms, the information processor31is configured to communicate with the refrigerant leak sensors5inside the corresponding ones of the plurality of rooms. In this case, the information processor31is configured to memorize the refrigerant leak sensors5, the indoor units2, and the stop valves30in units of groups for each room or for each plurality of neighboring rooms. When receiving the signal indicating the leak of the refrigerant from the refrigerant leak sensor5placed inside any one room, the information processor31is configured to transmit the request signal to all of the indoor units2and all of the stop valves30in the same group as the group of the refrigerant leak sensor5and the outdoor unit1.

When receiving the request signal, the stop valves30are each configured to close a valve and to stop the passage of the refrigerant. Therefore, the inflow of the refrigerant into the indoor units2is prevented. While not receiving the request signal, the stop valves30are each configured to open or closes the valve in response to a control signal. The refrigerant is allowed to flow by the opening action of the stop valve30, and its passage is stopped by the closing action.

The indoor control unit24in the indoor unit2receiving the request signal is configured to cause the indoor air-sending device21in the indoor unit2to perform processing for diffusing the leaking refrigerant in response to the request signal. Specifically, when the indoor air-sending device21is not in operation before the reception of the request signal, the indoor control unit24is configured to control the indoor air-sending device21such that the indoor air-sending device21starts its operation. When the indoor air-sending device21is in operation before the reception of the request signal, the indoor control unit24is configured to control the indoor air-sending device21, for example, such that the indoor air-sending device21increases the quantity of air. The refrigerant is diffused by the operation of the indoor air-sending device21.

Moreover, the indoor control unit24receiving the request signal is configured to control the notification unit23in the indoor unit2including the indoor control unit24such that the notification unit23issues a warning. The indoor control unit24receiving the request signal is configured to control the indoor flow control valve22in the indoor unit2such that the indoor flow control valve22closes its valve. In Embodiment, the indoor control unit24receiving the request signal is configured not to transmit the control signal to the outdoor unit1.

In Embodiment, when receiving the request signal, the outdoor unit1, in response to the request signal, the outdoor unit1is configured to control the compressor10such that the compressor10suspends its operation and to control the outdoor flow control valve14such that the outdoor flow control valve14closes its valve to prevent the refrigerant from flowing out toward the indoor units2. When receiving the control signal from the indoor unit2together with the request signal, the outdoor unit1in Embodiment is configured to assign a higher priority to the action in accordance with the request signal and performs it. That is, when receiving at least one request signal, the outdoor unit1is configured to suspend the operation of the compressor10and to close the outdoor flow control valve14.

A concrete example of actions of the air-conditioning system100according to Embodiment is described below with reference toFIG.2.FIG.2is a schematic diagram for describing the actions of the air-conditioning system when one or more indoor units are placed in each room.FIG.2illustrates an example in which three indoor units2are placed inside a room A and a single indoor unit2is placed inside a room B. In this example, the stop valves30in the refrigerant circuit4including each of the one or more indoor units2in one room are combined in a group. Thus, the stop valves30in the refrigerant circuit4including each of the three indoor units2inside the room A and the stop valves30in the refrigerant circuit4including the single indoor unit2inside the room B belong to different groups. In the example illustrated inFIG.2, the stop valves30and the refrigerant leak sensor5are included in the single stop valve unit3for each group. Thus, the stop valves30in the refrigerant circuit4including each of the three indoor units2inside the room A are housed in a single stop valve unit3, and the stop valves30in the refrigerant circuit4including the single indoor unit2inside the room B are housed in a different single stop valve unit3. The stop valves30and the refrigerant leak sensors5in a plurality of groups may be included in the single stop valve unit3.

In the description below, the stop valve unit3including the stop valves30in the refrigerant circuit4including each of the three indoor units2inside the room A is described as a stop valve unit3A. The stop valve unit3including the stop valves30in the refrigerant circuit4including the single indoor unit2inside the room B is described as a stop valve unit3B.

The refrigerant leak sensor5is placed inside the room A. The refrigerant leak sensor5may be housed in the stop valve unit3A. In the description below, the refrigerant leak sensor5placed inside the room A may be described as a refrigerant leak sensor5A. The refrigerant leak sensor5A is configured to communicate with the information processor31included in the stop valve unit3A. In the description below, the information processor31included in the stop valve unit3A may be described as an information processor31A.

The refrigerant leak sensor5is placed inside the room B. The refrigerant leak sensor5may be housed in the stop valve unit3B. In the description below, the refrigerant leak sensor5placed inside the room B may be described as a refrigerant leak sensor5B. The refrigerant leak sensor5B is configured to communicate with the information processor31included in the stop valve unit3B. In the description below, the information processor31included in the stop valve unit3B may be described as an information processor31B.

The information processor31A is configured to communicate with the indoor control unit24in each of the three indoor units2placed inside the room A. The information processor31B is configured to communicate with the indoor control unit24in the single indoor unit2placed inside the room B.

When detecting a leak of the refrigerant, the refrigerant leak sensor5A is configured to transmit a signal indicating the leak of the refrigerant to the information processor31A. When receiving the signal, the information processor31A is configured to transmit a request signal requesting the stop valves30included in the stop valve unit3A to close their valves. The stop valves30included in the stop valve unit3A are each configured to close the valve in accordance with the request signal. In the case where the above outdoor flow control valve14is disposed in the stop valve unit3A, the information processor31A is configured to transmit a request signal requesting the outdoor flow control valve14to close its valve. In this case, the outdoor flow control valve14is configured to close its valve in accordance with the request signal. The information processor31A is configured to transmit a request signal to the indoor control unit24in each of the three indoor units2placed inside the room A. The indoor control unit24receiving the request signal is configured to control the notification unit23such that the notification unit23issues a warning, configured to control the indoor air-sending device21such that the indoor air-sending device21sends air for diffusing the leaking refrigerant, and configured to control the indoor flow control valve22such that the indoor flow control valve22closes its valve.

When detecting a leak of the refrigerant, the refrigerant leak sensor5B is configured to transmit a signal indicating the leak of the refrigerant to the information processor31B. When receiving the signal, the information processor31B is configured to transmit a request signal requesting the stop valves30included in the stop valve unit3B to close their valves. The stop valves30included in the stop valve unit3B are each configured to close the valve in accordance with the request signal. In the case where the outdoor flow control valve14is disposed in the stop valve unit3B, the information processor31B is configured to transmit a request signal requesting the outdoor flow control valve14to close its valve. In this case, the outdoor flow control valve14is configured to close its valve in accordance with the request signal. The information processor31B is configured to transmit a request signal to the indoor control unit24in the single indoor unit2placed inside the room B. The indoor control unit24receiving the request signal is configured to control the notification unit23such that the notification unit23issues a warning, configured to control the indoor air-sending device21such that the indoor air-sending device21sends air for diffusing the leaking refrigerant, and configured to control the indoor flow control valve22such that the indoor flow control valve22closes its valve.

When receiving the signal indicating the leak of the refrigerant, the information processors31A and31B are each configured to transmit the request signal to the outdoor unit1. In response to the received request signal, the outdoor unit1is configured to control the compressor10such that the compressor10suspends its operation and configured to control the outdoor flow control valve14such that the outdoor flow control valve14closes its valve.

In the case where the stop valves30in the refrigerant circuits4including the indoor units2inside the rooms A and B are collectively included in the single stop valve unit3, the information processor31included in the stop valve unit3is configured to communicate with the indoor control units24in the indoor units2arranged inside the rooms A and B. When receiving a signal indicating a leak of the refrigerant from the refrigerant leak sensor5A, the information processor31is configured to transmit a request signal to the outdoor unit1and also transmit the request signal to the indoor units2and the stop valves30in the same group as the group of the refrigerant leak sensor5A. Similarly, when receiving a signal indicating a leak of the refrigerant from the refrigerant leak sensor5B, the information processor31is configured to transmit the request signal to the outdoor unit1and also transmit the request signal to the indoor unit2and the stop valves30in the same group as the group of the refrigerant leak sensor5B.

A hardware configuration of the air-conditioning system100according to Embodiment is described below. The structure of each of the outdoor unit1, the indoor heat exchanger20, the indoor air-sending device21, the indoor flow control valve22, the stop valve30, and the refrigerant leak sensor5is substantially the same as the structure in related art, and its description is omitted. The functions of the information processor31and the indoor control unit24can be achieved by, for example, a structure including a processor, such as a central processing unit (CPU) and a micro processing unit (MPU), a memory, such as a read-only memory (ROM) and a random-access memory (RAM), a communication interface circuit, and other elements. The communication functions of the information processor31and the indoor control unit24can be achieved by the use of the communication interface circuit. The functions of the information processor31other than the communication function can be achieved by the processor reading various programs stored in the memory and executing them. Similarly, the functions of the indoor control unit24other than the communication function can be achieved by the processor reading various programs stored in the memory and executing them. All or part of the functions of the information processor31and the indoor control unit24may be achieved by a dedicated hardware device.

A flow of processing by the stop valve units3, the outdoor unit1, and the indoor units2in the case where the refrigerant is detected inside a room is described below.FIG.3is a sequence diagram illustrating an example flow of processing in the air-conditioning system in the case where the refrigerant is detected inside a room. Here, the indoor unit2belongs to the same group as the group of the refrigerant leak sensor5detecting the leak of the refrigerant.

At step S1, the information processor31receives a signal indicating a leak of the refrigerant from the refrigerant leak sensor5. At step S2, the information processor31transmits a request signal to the stop valves30in the same group as the group of the refrigerant leak sensor5. At step S3, the stop valve30receiving the request signal closes its valve in response to the request signal. At step S4, the information processor31transmits the request signal to the indoor unit2in the same group as the group of the refrigerant leak sensor5. At step S5, the indoor control unit24receiving the request signal controls the notification unit23such that the notification unit23issues a warning. In response to the request signal, the notification unit23issues the warning. The indoor control unit24controls the indoor air-sending device21such that the indoor air-sending device21sends air for diffusing the leaking refrigerant. In response to the control, the indoor air-sending device21sends air for diffusing the leaking refrigerant. The indoor control unit24controls the indoor flow control valve22such that the indoor flow control valve22closes its valve. In response to the control, the indoor flow control valve22closes its valve.

At step S6, the information processor31transmits the request signal to the outdoor unit1. At step S7, the outdoor unit1receiving the request signal controls the compressor10such that the compressor10suspends its operation and controls the outdoor flow control valve14such that the outdoor flow control valve14closes its valve. The processing at step S2, the processing at step S4, and the processing at step S6may be performed in parallel to each other or in any order. The processing at step S3, the processing at step S5, and the processing at step S7may be performed upon receipt of the request signal, in parallel to each other or in any order.

Next, differences between the air-conditioning system100according to Embodiment and an air-conditioning system101in related art are described.FIG.4is a schematic diagram illustrating an example of the air-conditioning system in related art. The air-conditioning system101in related art includes the outdoor unit1and a plurality of indoor units6and does not include the stop valve units3. In the air-conditioning system101, in place of the above stop valve units3, the stop valves30are disposed inside or outside each of the indoor units6. In the air-conditioning system101, the refrigerant leak sensor5is disposed inside or outside each of the indoor units6. The indoor units6each include the above indoor heat exchanger20, the above indoor air-sending device21, the indoor flow control valve22, and the notification unit23, like the above-described indoor unit2. The indoor units6each include an indoor controller60corresponding to the combination of the above information processor31and the above indoor control unit24. That is, the indoor controller60in the indoor unit6in related art has the function of the above information processor31.

In related art, when detecting a leak of refrigerant, the refrigerant leak sensor5in the indoor unit6is configured to transmit a signal indicating the leak of the refrigerant to the indoor controller60in the indoor unit6. The indoor controller60in the indoor unit6in which the leak of the refrigerant is detected is configured to control the notification unit23such that the notification unit23issues a warning and configured to control the stop valves30and the indoor flow control valve22in the indoor unit6such that the stop valves30and the indoor flow control valve22close their valves. The indoor controller60in the indoor unit6is configured to transmit the request signal for the case where the refrigerant leaks to the outdoor unit1.

When the refrigerant leak sensor5in the indoor unit6does not detect the leak of the refrigerant, the indoor controller60in the indoor unit6is configured to perform substantially the same processing as the processing by the above indoor control unit24. Thus, the indoor controller60in the indoor unit6in which the leak of the refrigerant is not detected is configured to transmit a control signal for the case where the leak of the refrigerant is not detected to the outdoor unit1.

The outdoor unit1is configured to perform the processing by using the request signal or the control signal from each of the plurality of indoor units6. When, however, the number of indoor units6in the air-conditioning system101is large, the amount of data of signals to be processed by the outdoor unit1is large. The traffic in transmission and reception of signals between the outdoor unit1and the indoor units6is large.

Even when the outdoor unit1receives the request signal from an indoor unit6detecting the leak of the refrigerant, in a case where the outdoor unit1receives the control signal requiring an outflow of the refrigerant from another indoor unit6, the outdoor unit1in related art may flow the refrigerant out toward the indoor unit6. In the case where the plurality of indoor units6are placed inside the same room, however, problems described below may arise. A possible case where the refrigerant leak sensor5in the indoor unit6in which the refrigerant leaks does not detect the leak of the refrigerant and the refrigerant leak sensor5in another indoor unit6detects the leak of the refrigerant is discussed. In this case, the indoor unit6that does not detect the leak of the refrigerant may not close the stop valves30and may transmit the control signal requiring the outflow of the refrigerant to the outdoor unit1. The processing by the outdoor unit1in response to the control signal may cause the refrigerant to flow into the indoor unit6and lead to further leaks of the refrigerant.

In related art, only the notification unit23in the indoor unit6in which the refrigerant leak sensor5detecting the leak of the refrigerant is disposed issues a warning about the leak of the refrigerant. In actuality, however, the leak of the refrigerant may occur in a different indoor unit6, and, when the refrigerant leak sensor5in the different indoor unit6does not detect the leak of the refrigerant, a user of the different indoor unit6may not be sufficiently warned. Moreover, in related art, the indoor air-sending device21in the indoor unit6in which the refrigerant leak sensor5does not detect the leak of the refrigerant is disposed does not perform air-sending processing for reducing the concentration of the leaking refrigerant. Thus, when the refrigerant leak sensor5in the indoor unit6in which the refrigerant leaks does not detect the leak of the refrigerant, the refrigerant may accumulate, and such a configuration may lead to an increased concentration of the refrigerant.

Moreover, the air-conditioning system101in related art also has the following problems. For the air-conditioning system100, the air-conditioning system101, and other systems, all the refrigerant leak sensors5need to be changed to change the type of the refrigerant, to change the characteristics of the refrigerant leak sensors5, to replace the refrigerant leak sensors5because of age deterioration, or in other cases. As described above, however, in the air-conditioning system101in related art, the refrigerant leak sensor5is disposed in each of the indoor units6. Thus, when the number of indoor units2in the air-conditioning system101is large, the burden of work in replacing the refrigerant leak sensors5is significant. An example of the characteristics of the refrigerant leak sensors5may be a threshold value of the concentration of the refrigerant used in the refrigerant leak sensor5when it determines whether the refrigerant leaks or not. The threshold value depends on the type of the refrigerant or other factors.

In contrast to the air-conditioning system101in related art, the air-conditioning system100according to Embodiment has the following advantageous effects. First, in Embodiment, the stop valves30for stopping the inflow of the refrigerant into the one or more indoor units2inside the room are combined in the stop valve unit3. When the refrigerant leak sensor5inside the room detects the leak of the refrigerant, the information processor31in the stop valve unit3is configured to receive the signal indicating the leak of the refrigerant from the refrigerant leak sensor5. The information processor31receiving the signal is configured to transmit the request signal to the outdoor unit1, the one or more indoor units2, the stop valves30, and other elements, and the request signal requests performing predetermined processing for the occurrence of the leak of the refrigerant. At this time, the one or more indoor units2receiving the request signal are each configured not to transmit the control signal to the outdoor unit1. Thus, the traffic in the air-conditioning system100is to be reduced. When receiving at least one request signal, the outdoor unit1is configured to perform the processing in response to the request signal, and thus the amount of data processing can be reduced, in comparison with the case where processing using the control signal as well is performed.

When the outdoor unit1suspends its operation in response to the request signal, the inflow of the refrigerant toward the indoor units2is prevented. All the stop valves30receiving the request signal are each configured to perform the closing action in accordance with the request signal. When the outdoor flow control valve14is included in the stop valve unit3, the information processor31is configured to transmit the request signal requesting closing to the outdoor flow control valve14, and the outdoor flow control valve14is configured to close its valve in accordance with the request signal. Thus, the inflow of the refrigerant into all the indoor units2inside the room is prevented. Thus, situations where the refrigerant flows into the indoor unit2in which the refrigerant leaks can be prevented, and further leaks can be prevented.

In Embodiment, all the indoor units2in the same room are each configured to issue a warning indicating the leak of the refrigerant in accordance with the request signal. Thus, a user of the same room can be sufficiently notified. Because the indoor air-sending device21in each of all the indoor units2in the same room is configured to perform the air-sending operation for diffusing the refrigerant, the refrigerant is further diffused and the increase in concentration of the refrigerant is further prevented, in comparison with the air-conditioning system in related art.

In Embodiment, the refrigerant leak sensor5is disposed for not each indoor unit2but each group of indoor units2in the same room. The number of refrigerant leak sensors5disposed for the group of indoor units2may be one or more. The one or more refrigerant leak sensors5for the group of the indoor units2in the same room may be housed in the stop valve unit3. Thus, in the case where the number of indoor units2in the air-conditioning system100is large or in other cases, the burden of the processing of replacing the refrigerant leak sensors5is to be reduced.

As described above, the air-conditioning system100according to Embodiment includes the outdoor unit1, the plurality of indoor units2, and the one or more refrigerant leak sensors5. In the refrigerant circuit4in which the refrigerant is circulated, the outdoor unit1is configured to exchange heat between outdoor air and the refrigerant. In the refrigerant circuit4, the indoor units2are each configured to exchange heat between the refrigerant and air inside the room and to perform air conditioning inside the room. The one or more refrigerant leak sensors5are each configured to detect a leak of the refrigerant from the refrigerant circuit4. The refrigerant leak sensors5are each arranged separately from the outdoor unit1and the plurality of indoor units2. Thus, work for the outdoor unit1and the plurality of indoor units2in replacing the refrigerant leak sensors5is not necessary. Accordingly, the burden of work of replacing the refrigerant leak sensors5is reduced.

In Embodiment, the number of refrigerant leak sensors5in the room is less than or equal to the number of indoor units2inside the room. Thus, the burden of work of replacing the refrigerant leak sensors5is reduced.

The air-conditioning system100in Embodiment further includes the plurality of stop valves30each configured to stop the inflow of the refrigerant into the plurality of indoor units2in the case where the refrigerant leaks. The plurality of stop valves30are each arranged separately from the outdoor unit1and the indoor units2. Thus, work for the outdoor unit1and the indoor units2is not needed in work for the stop valves30, and the burden of the work for the stop valves30is lightened.

The air-conditioning system100in Embodiment further includes the one or more stop valve units3. The one or more stop valve units3each include the plurality of stop valves30housed in its casing. Thus, the burden of work for the stop valves30is further reduced.

The stop valve unit3in Embodiment includes the one or more refrigerant leak sensors5. Therefore, the burden of replacement work for the refrigerant leak sensors5is further reduced.

The stop valve unit3in Embodiment further includes the information processor configured to control the plurality of stop valves30included in the stop valve unit3. When detecting the leak of the refrigerant inside a room, the refrigerant leak sensor5is configured to transmit the signal indicating the leak of the refrigerant to the information processor31. The information processor31is configured to control the plurality of stop valves30each configured to stop the inflow of the refrigerant into the one or more indoor units2placed inside a room as a single group. When receiving the signal indicating the leak of the refrigerant inside the room from the refrigerant leak sensor5, the information processor31is configured to transmit the request signal to the plurality of stop valves30included in the group including the stop valves30each configured to stop the inflow of the refrigerant into the one or more indoor units2inside the room, and the request signal causes performing the predetermined action for the case where the refrigerant leaks. When receiving the request signal, the stop valves30are each configured to close the valve to stop the passage of the refrigerant in accordance with the request signal. Therefore, in the case where the leak of the refrigerant is detected inside the room, the leak of the refrigerant from the one or more indoor units2inside the room is prevented.

In Embodiment, the plurality of stop valves30each configured to stop the inflow of the refrigerant into the one or more indoor units2placed inside a room are included as a single group in the single stop valve unit3. Therefore, the burden of work for the stop valves30each configured to stop the inflow of the refrigerant into the one or more inside a room is reduced.

In Embodiment, the one or more refrigerant leak sensors5placed inside each room are combined in the single group and are included in the single stop valve unit3. Therefore, the burden of work for the refrigerant leak sensors5configured to detect the leak of the refrigerant for each rooms is lightened.

The stop valve unit3in Embodiment further includes the information processor31. The information processor3131is configured to control the plurality of stop valves30included in the stop valve unit3. When detecting the leak of the refrigerant inside the room, the refrigerant leak sensor5is configured to transmit the signal indicating the leak of the refrigerant to the information processor31. When receiving the signal indicating the leak of the refrigerant, the information processor31transmits, to the plurality of stop valves30included in the stop valve unit3, the request signal for causing performing the predetermined action for the case where the refrigerant leaks. When receiving the request signal, the stop valves30are each configured to close the valve to stop the passage of the refrigerant in accordance with the request signal. Therefore, the air-conditioning system100according to Embodiment can stop the inflows of the refrigerant into the one or more indoor units2inside the room where the refrigerant leaks all at once, and the leak of the refrigerant can be reliably prevented.

When receiving the signal indicating the leak of the refrigerant, the information processor31in Embodiment is configured to transmit, to the outdoor unit1, the request signal for causing performing the predetermined action for the case where the refrigerant leaks. When receiving the request signal, the outdoor unit1is configured to suspend its action in accordance with the request signal. In the case where the leak of the refrigerant is detected, because the request signal from the information processor31causes the outdoor unit1to suspend its action, the inflow of the refrigerant toward the indoor units2can be prevented, and further leaks of the refrigerant can be prevented.

The indoor unit2in Embodiment is configured to transmit the control signal for controlling the outdoor unit1to the outdoor unit1. Therefore, the indoor units2can apply an air-conditioning operation desired by a user to the outdoor unit1. When receiving the request signal, the outdoor unit1in Embodiment is configured to suspend its action in accordance with the request signal, even in a case where the outdoor unit1receives the control signal. Because the outdoor unit1suspends its action in accordance with the request signal even in a case where the outdoor unit1receives the control signal requiring the outflow of the refrigerant from another indoor unit2, the inflow of the refrigerant toward the indoor unit2in which the refrigerant leaks can be prevented. Therefore, further leaks of the refrigerant can be prevented. The outdoor unit1is configured to suspend its action in response to the request signal alone, in place of the processing using the request signal and the control signal. Thus, the burden of data processing by the outdoor unit1can be reduced.

When receiving the signal indicating the leak of the refrigerant from the refrigerant leak sensor5detecting the leak of the refrigerant inside the room, the information processor31in Embodiment is configured to transmit the request signal to the one or more indoor units2inside the room. When receiving the request signal, the indoor units2are each configured not to transmit the control signal for controlling the outdoor unit1in accordance with the request signal. Therefore, the traffic in the air-conditioning system100is to be reduced. Because it is not necessary for the outdoor unit1to perform the processing of receiving the control signal and the processing using the control signal, the amount of processing by the outdoor unit1can be reduced.

When receiving the signal indicating the leak of the refrigerant from the refrigerant leak sensor5detecting the leak of the refrigerant inside the room, the information processor31in Embodiment is configured to transmit, to the one or more indoor units2inside the room, the request signal for causing performing the predetermined action for the case where the refrigerant leaks. The indoor unit2includes the indoor air-sending device21configured to send air into the room and the indoor control unit24configured to control the indoor air-sending device21. When receiving the request signal from the information processor31, the indoor control unit24is configured to control the indoor air-sending device21such that the indoor air-sending device21performs air-sending processing for diffusing the leaking refrigerant in accordance with the request signal. In the case where the leak of the refrigerant is detected inside the room, the information processor31is configured to transmit the request signal to the one or more indoor units2inside the room all at once, and the indoor air-sending device21in each of the indoor units2is configured to perform the air-sending processing in response to the request signal. Thus, the diffusion of the refrigerant inside the room is further promoted. Therefore, the rise in the concentration of the refrigerant inside the room can be prevented.

When receiving the signal indicating the leak of the refrigerant from the refrigerant leak sensor5detecting the leak of the refrigerant inside the room, the information processor31in Embodiment is configured to transmit, to the indoor units2inside the room, the request signal for causing performing the predetermined action for the case where the refrigerant leaks. The indoor unit2includes the notification unit23configured to provide notification of the leak of the refrigerant and the indoor control unit24configured to control the notification unit23. When receiving the request signal from the information processor31, the indoor control unit24is configured to control the notification unit23such that the notification unit23provides notification of the leak of the refrigerant in accordance with the request signal. In the case where the leak of the refrigerant is detected inside the room, the information processor31is configured to transmit the request signal to the one or more indoor units2inside the room all at once, and the indoor units2are each configured to issue a warning in accordance with the request signal. Thus, a user inside the room can be sufficiently notified of the leak of the refrigerant.