JP5794279B2 - Air conditioner - Google Patents

Description

  The present invention relates to an air conditioner including a refrigerant circuit, for example.

An air conditioner is generally provided with a refrigerant circuit having an outdoor heat exchanger. In conventional air conditioners, most of the refrigerant is exchanged with the outdoor unit when the compressor is stopped after operation in order to prevent leakage of refrigerant into the room when the piping of the refrigerant circuit is damaged. Some are controlled so as to be closed in a container (for example, Patent Document 1). Moreover, when moving an air conditioner, a refrigerant | coolant is often enclosed by the outdoor heat exchanger of an outdoor unit by pump down driving | operation.

Japanese Patent No. 4269353

In a conventional air conditioner, the compressor and the outdoor heat exchanger may communicate with each other via a four-way switching valve in a state where the refrigerant is closed in the outdoor unit. In this case, many refrigerants move from the outdoor heat exchanger into the compressor, and many refrigerants and refrigeration oil are mixed in the compressor. Therefore, for example, when the compressor is started, the refrigeration oil is easily discharged from the compressor together with the refrigerant, and there is a problem that the reliability of the compressor is lowered.

Therefore, an object of the present invention is to provide an air conditioner that can improve the reliability of the compressor by preventing the refrigerant from moving from the outdoor heat exchanger into the compressor when the refrigerant is confined in the outdoor unit. It is to be.

An air conditioner according to a first invention includes a refrigerant circuit in which a compressor, a four-way switching valve, an outdoor heat exchanger, and a plurality of indoor heat exchangers are connected, and the four-way switching valve includes: A first state in which the discharge side of the compressor communicates with the outdoor heat exchanger side and the suction side of the compressor communicates with the indoor heat exchanger side; the discharge side of the compressor and the indoor heat The refrigerant circuit may be in a second state in which the exchanger side is communicated and the suction side of the compressor and the outdoor heat exchanger side are communicated, and the refrigerant circuit includes the indoor heat exchanger and the outdoor side. A first closing mechanism disposed between the heat exchanger, a second closing mechanism disposed between the outdoor heat exchanger and the four-way switching valve, the outdoor heat exchanger, and the plurality of indoors. A first header connected between the heat exchanger and a contact between the four-way switching valve and the plurality of indoor heat exchangers; The second header, the first header and the second header are connected to each other, and the indoor heat exchanger is disposed in each of the plurality of branch paths, and in each of the plurality of branch paths, A third closing mechanism disposed between the first header and the indoor heat exchanger; a fourth closing mechanism disposed between the second header and the indoor heat exchanger; and an outdoor unit or an indoor unit. A refrigerant leakage detection sensor for detecting refrigerant leakage in the compressor, the compressor, the four-way switching valve, the outdoor heat exchanger, a first closing mechanism, a second closing mechanism, a third closing mechanism, and a fourth closing mechanism. Is arranged inside the outdoor unit, and the plurality of indoor heat exchangers are arranged inside the plurality of indoor units, respectively, and when a refrigerant leak is detected in the outdoor unit during heating operation, A third closing mechanism arranged and The fourth closing mechanism is closed to stop the heating operation, and when a refrigerant leak is detected in the indoor unit during the heating operation, the third closing mechanism and the fourth closing mechanism of the branch path where the refrigerant leakage is detected are closed. However, after the third closing mechanism and the fourth closing mechanism of the branch path where the refrigerant leakage is not detected are kept open and the second closing mechanism is closed and the heating operation is continued, the refrigerant leakage is not detected. The remaining third closing mechanism and fourth closing mechanism of the branch path are closed, and the heating operation is stopped .

In this air conditioner, for example, when the piping of the refrigerant circuit is damaged or when the air conditioner is moved, the outdoor heat exchanger and the four-way switching valve are connected in a state where the refrigerant is closed in the outdoor heat exchanger. Since the space can be closed by the second closing mechanism, the compressor and the outdoor heat exchanger do not communicate with each other. Therefore, in a state where the refrigerant is confined in the outdoor unit, the refrigerant does not move from the outdoor heat exchanger into the compressor, so that a large amount of refrigerant and refrigerating machine oil are not mixed in the compressor. Reliability can be improved.

In this air conditioner, since the first closing mechanism and the second closing mechanism are arranged inside the outdoor unit, the refrigerant can be confined only inside the outdoor unit.
In this air conditioner, a refrigerant circuit in which a plurality of indoor heat exchangers are connected to one outdoor heat exchanger
In this case, the reliability of the compressor can be improved.
In this air conditioner, if there is a refrigerant leak in any of a plurality of branch circuits, a plurality of
Of these branch circuits, only the branch circuit where the refrigerant leaked can be closed.

In the air conditioner pertaining to the second invention, in the air conditioner pertaining to the first invention, the refrigerant circuit is an electric motor for flow rate adjustment disposed between the outdoor heat exchanger and the indoor heat exchanger. A valve is provided, and the first closing mechanism is an electromagnetic valve different from the motor-operated valve.

In this air conditioner, an electromagnetic valve is used as the first closing mechanism for confining the refrigerant in the outdoor heat exchanger. It can be reliably trapped in the heat exchanger.

In the air conditioner pertaining to the third invention, in the air conditioner pertaining to the first or second invention, the first closing mechanism and the second closing mechanism are configured to be in a closed state when not energized. It is characterized by that.

In this air conditioner, even when a power failure occurs in a state where the refrigerant is closed in the outdoor heat exchanger, the electromagnetic valve is closed, so that the state where the refrigerant is closed is maintained.

In the air conditioner pertaining to the fourth invention, in the air conditioner pertaining to any one of the first to third inventions, a pressure sensor for detecting refrigerant leakage is disposed in each of the plurality of branch paths. And

In this air conditioner, the refrigerant leak in the refrigerant circuit can be detected without arranging the refrigerant leak detection sensor in both the indoor unit and the outdoor unit.

In an air conditioner according to a fifth aspect of the present invention, in the air conditioner according to the fourth aspect of the present invention, the pressure sensor includes the third closing mechanism and the fourth closing mechanism described above in each of the plurality of branch paths. It is arranged between them.

In this air conditioner, when there is a refrigerant leak in any of a plurality of branch circuits, the branch circuit in which the refrigerant leaks can be specified.

In the air conditioner pertaining to the sixth invention, in the air conditioner pertaining to any one of the first to fifth inventions, the first header and the second header are arranged inside an outdoor unit, The outdoor unit includes a plurality of pipe connection portions that are connected to either the first header or the second header and to which pipes for connecting the indoor units are connected.

In this air conditioner, the reliability of the compressor can be improved even in an outdoor unit to which a plurality of indoor units are connected.

In the air conditioner pertaining to the seventh invention, in the air conditioner pertaining to any one of the first to sixth inventions, the refrigerant is an R32 refrigerant.

In this air conditioner, the reliability of the compressor can be improved even when an R32 refrigerant having a slight flammability is used as the refrigerant.

  As described above, according to the present invention, the following effects can be obtained.

In the first invention, for example, when the piping of the refrigerant circuit is damaged or when the air conditioner is moved, in the state where the refrigerant is closed in the outdoor heat exchanger, the outdoor heat exchanger and the four-way switching valve Since the space can be closed by the second closing mechanism, the compressor and the outdoor heat exchanger do not communicate with each other. Therefore, in a state where the refrigerant is closed in the outdoor heat exchanger, the refrigerant does not move from the outdoor heat exchanger into the compressor, so that many refrigerants and refrigeration oil are not mixed in the compressor, The reliability of the compressor can be improved.

In the first invention, since the first closing mechanism and the second closing mechanism are arranged inside the outdoor unit, the refrigerant can be confined only inside the outdoor unit.
In the first invention, a refrigerant circuit in which a plurality of indoor heat exchangers are connected to one outdoor heat exchanger.
Even in this case, the reliability of the compressor can be improved.
In the first invention, if there is a refrigerant leak in any of the plurality of branch circuits, a plurality of minutes
Only the branch circuit where the refrigerant leaked can be closed.

In the second invention, the electromagnetic valve is used as the first closing mechanism for confining the refrigerant in the outdoor heat exchanger. Therefore, the refrigerant is placed in the outdoor rather than the case where the electric valve for flow rate adjustment is used as the first closing mechanism. It can be reliably trapped in the heat exchanger.

In the third aspect of the invention, even when a power failure occurs when the refrigerant is closed in the outdoor heat exchanger, the solenoid valve is closed, so that the state where the refrigerant is closed is maintained.

In the fourth invention, refrigerant leakage in the refrigerant circuit can be detected without arranging the refrigerant leakage detection sensor in both the indoor unit and the outdoor unit.

In the fifth invention, when there is a refrigerant leak in any of the plurality of branch circuits, the branch circuit in which the refrigerant leaked can be specified.

In the sixth invention, the reliability of the compressor can be improved even in an outdoor unit to which a plurality of indoor units are connected.

In the seventh invention, the reliability of the compressor can be improved even when the R32 refrigerant having a slight flammability is used as the refrigerant.

It is a circuit diagram which shows the refrigerant circuit of the air conditioner which concerns on 1st Embodiment of this invention. It is a figure explaining the control part of the air conditioner of FIG. It is a figure explaining the operation | movement when a refrigerant | coolant leak is detected when the air_conditioning | cooling apparatus of FIG. 1 is performing the cooling operation. It is a figure explaining operation | movement when a refrigerant | coolant leak is detected when the heating operation is performed in the air conditioner of FIG. It is a figure explaining operation | movement when there exists a driving | operation stop instruction | indication in the air conditioner of FIG. It is a circuit diagram which shows the refrigerant circuit of the air conditioner which concerns on 2nd Embodiment of this invention. It is a figure explaining the control part of the air conditioner of FIG. It is a figure explaining operation | movement when a refrigerant | coolant leak is detected when the air_conditioning | cooling apparatus of FIG. 6 is performing air_conditionaing | cooling operation. It is a figure explaining operation | movement when a refrigerant | coolant leak is detected when the heating operation is performed in the air conditioner of FIG. It is a circuit diagram which shows the refrigerant circuit of the air conditioner which concerns on 3rd Embodiment of this invention. It is a figure explaining the control part of the air conditioner of FIG. It is a figure explaining the operation | movement when a refrigerant | coolant leak is detected when the air_conditioning | cooling apparatus of FIG. 10 is performing the cooling operation. It is a figure explaining operation | movement when a refrigerant | coolant leak is detected when the heating operation is performed in the air conditioner of FIG. It is a figure explaining operation | movement when there exists a driving | operation stop instruction | indication in the air conditioner of FIG.

  Hereinafter, an embodiment of an air conditioner 1 according to the present invention will be described.

(First embodiment)
<Overall configuration of the air conditioner 1>
As shown in FIG. 1, the air conditioner 1 of this embodiment is provided with the three indoor units 2 each installed indoors, and the outdoor unit 3 installed outdoors. The indoor unit 2 has a liquid side connection part 2a to which the liquid side pipe 5 is connected and a gas side connection part 2b to which the gas side pipe 6 is connected. It has the liquid side connection part 3a connected, and the gas side connection part 3b to which the gas side piping 6 is connected. Therefore, in the air conditioner 1, the liquid side connection part 2a of the indoor unit 2 is used.
And the liquid side connection part 3a of the outdoor unit 3 are connected by a liquid side pipe 5, and the gas side connection part 2b of the indoor unit 2 and the gas side connection part 3b of the outdoor unit 3 are connected by a gas side pipe 6. The

The air conditioner 1 includes a refrigerant circuit constituted by an indoor unit 2, an outdoor unit 3, a liquid side pipe 5, and a gas side pipe 6. The refrigerant circuit is configured by connecting a compressor 10, a four-way switching valve 11, an outdoor heat exchanger 13, and three indoor heat exchangers 16, and includes the compressor 10, the four-way switching valve 11, and the outdoor. The heat exchanger 13 is arranged inside the outdoor unit 3, and the three indoor heat exchangers 16 are arranged inside the three indoor units 2, respectively. In the present embodiment, R32 refrigerant is used as the refrigerant.

The four-way switching valve 11 communicates the discharge side of the compressor 10 and the outdoor heat exchanger 13 side, and the cooling state (first state) that communicates the suction side of the compressor 10 and the indoor heat exchanger 16 side. And a heating state (second state) in which the discharge side of the compressor 10 and the indoor heat exchanger 16 side are communicated and the suction side of the compressor 10 and the outdoor heat exchanger 13 side are communicated. To get.

In the refrigerant circuit inside the outdoor unit 3, between the four-way switching valve 11 and the outdoor heat exchanger 13,
A solenoid valve 12 is arranged. The electromagnetic valve 12 can take either an open state or a closed state, and is controlled by the control unit 50. In the present embodiment, the electromagnetic valve 12 is
In this invention, it corresponds to the 2nd closing mechanism arrange | positioned between the outdoor heat exchanger 13 and the four-way selector valve 11. FIG.

In the refrigerant circuit inside the outdoor unit 3, a liquid closing valve 20 is disposed on the indoor unit 2 side from the outdoor heat exchanger 13, and a gas closing valve 21 is disposed on the indoor unit 2 side from the four-way switching valve 11. Is placed. The liquid closing valve 20 and the gas closing valve 21 can take either an open state or a closed state, respectively, and are switched manually.

In the refrigerant circuit inside the outdoor unit 3, the indoor unit 2 side (outdoor heat exchanger 13) from the liquid shut-off valve 20.
Between the gas shutoff valve 21 and the indoor unit 2 side (between the four-way switching valve 11 and the plurality of indoor heat exchangers 16). In the second header 31
Is placed. The refrigerant circuit from the outdoor heat exchanger 13 is branched into three in the first header 30 and connected to the three liquid side connection portions 3a of the outdoor unit 3, respectively. On the other hand, four-way switching valve 1
The refrigerant circuit from 1 is branched into three in the second header 31 and connected to the three gas side connection portions 3b of the outdoor unit 3, respectively. Therefore, the refrigerant circuit includes the first header 30 and the second header.
Each of the headers 31 is connected to each other, and the indoor heat exchanger 2 is provided with three branch paths.

In each of the three branch paths, the motor-operated valve 14 is disposed between the first header 30 and the liquid side connection portion 3a. The motor-operated valve 14 can take a plurality of openings corresponding to the open state and the closed state, and is controlled by the control unit 50. The electric valve 14 adjusts the refrigerant flow rate in the branch circuit for flow rate adjustment, and also has a function as an expansion valve. Moreover, the motor operated valve 14 is a motor operated valve that is closed when not energized. In the present embodiment, the motor-operated valve 14 is a first valve disposed between the indoor heat exchanger 16 and the outdoor heat exchanger 13 in the present invention.
It corresponds to a closing mechanism and also corresponds to a third closing mechanism disposed between the first header 30 and the indoor heat exchanger 16.

In each of the three branch circuits, between the second header 31 and the gas side connection portion 3b,
A solenoid valve 15 is arranged. The electromagnetic valve 15 can take either an open state or a closed state, and is controlled by the control unit 50. Further, the electromagnetic valve 15 is an electromagnetic valve that is closed when not energized. In the present embodiment, the electromagnetic valve 15 corresponds to a fourth closing mechanism disposed between the second header 31 and the indoor heat exchanger 16.

The air conditioner 1 can be operated in a cooling operation mode and a heating operation mode,
With the remote control, select one of the operations to perform the operation start operation, operation switching operation,
An operation for stopping the operation or changing the set temperature of the room temperature can be performed.

In the cooling operation mode, the refrigerant discharged from the compressor 10 sequentially flows from the four-way switching valve 11 to the outdoor heat exchanger 12, the electric valve 14, and the indoor heat exchanger 16 as indicated by the broken line arrows in the figure. A cooling cycle is formed in which the refrigerant that has passed through the exchanger 16 returns to the compressor 10 through the four-way switching valve 11. That is, the outdoor heat exchanger 13 functions as a condenser, and the indoor heat exchanger 16 functions as an evaporator.

On the other hand, in the heating operation mode, when the four-way switching valve 11 is switched, the refrigerant discharged from the compressor 10 is transferred from the four-way switching valve 11 to the indoor heat exchanger 16 and the motor-operated valve 14 as indicated by solid arrows in the figure. Then, a heating cycle is formed in which the refrigerant flows in order to the outdoor heat exchanger 13 and the refrigerant that has passed through the outdoor heat exchanger 13 returns to the compressor 10 through the four-way switching valve 11. That is, the indoor heat exchanger 16 functions as a condenser and the outdoor heat exchanger 13 functions as an evaporator.

The three indoor units 2 are each provided with a refrigerant leak detection sensor 17, and the outdoor unit 3 is provided with a refrigerant leak detection sensor 18. The refrigerant leak detection sensors 17 and 18 are connected to the control unit 50 of the air conditioner 1, and output a signal indicating refrigerant leak detection to the control unit 50 when refrigerant leakage is detected. Therefore, in the air conditioner 1 of the present embodiment, the refrigerant leak detection sensor 17 can detect the refrigerant leak in the room and the refrigerant leak detection sensor 18 can detect the refrigerant leak in the room.

As shown in FIG. 2, the control unit 50 of the air conditioner 1 includes a compressor 10, a four-way switching valve 11, an electromagnetic valve 12, three electric valves 14, three electromagnetic valves 15, 3 Two refrigerant leak detection sensors 17 and a refrigerant leak detection sensor 18 are connected to each other. Therefore, the control unit 50
When the refrigerant leakage detection sensors 17 and 18 detect refrigerant leakage indoors or outdoors, the solenoid valve 12, the three motor-operated valves 14, and the three solenoid valves 15 can be controlled.

Next, control (flow) of the air conditioner 1 of the present embodiment will be described with reference to FIGS.

First, the control of the air conditioner 1 when refrigerant leakage occurs during the cooling operation will be described with reference to FIG. Hereinafter, the cooling operation includes a dehumidifying operation. During the cooling operation (S1), it is determined whether or not a refrigerant leak is detected by the refrigerant leak detection sensors 17 and 18 (S2), and this is repeated until a refrigerant leak is detected. When refrigerant leakage is detected (
S2: Yes), motor-operated valve 14 (a closing mechanism downstream of the outdoor heat exchanger 13 in the refrigerant flow direction)
Is closed (S3), and the cooling operation is continued with the motor-operated valve 14 being closed (S4).
As a result, the refrigerant in the refrigerant circuit is prevented from flowing downstream (in the indoor unit side) in the refrigerant flow direction from the motor operated valve 14, and the refrigerant in the refrigerant circuit is sequentially stored in the outdoor heat exchanger 13.

Thereafter, the electromagnetic valve 12 (a closing mechanism on the upstream side in the refrigerant flow direction from the outdoor heat exchanger 13) is closed at a predetermined timing (S5), and the cooling operation is stopped (S6). Therefore, since the refrigerant stored in the outdoor heat exchanger 13 is confined between the motor-operated valve 14 and the electromagnetic valve 12, a large amount of refrigerant is stored indoors when the refrigerant pipe is damaged and refrigerant leaks. Or leakage outside the room is prevented. The timing for closing the electromagnetic valve 12 is preferably after most of the refrigerant in the refrigerant circuit is stored in the outdoor heat exchanger 13. For example, motorized valve 1
A predetermined time until most of the refrigerant in the refrigerant circuit is stored in the outdoor heat exchanger 13 after closing 4 may be determined in advance, and the electromagnetic valve 12 may be closed when the predetermined time elapses.

In the cooling operation, the refrigerant mainly stays on the outdoor unit 3 side. Therefore, in the control of the air conditioner 1, since the refrigerant on the outdoor unit 3 side does not move to the indoor unit 2 side, for example, when the refrigerant pipe on the indoor unit 2 side is broken, a large amount of refrigerant may leak into the room. It is suppressed. In the control of the air conditioner 1, the refrigerant that has accumulated on the outdoor unit 3 side is quickly removed from the outdoor heat exchanger 13.
Therefore, for example, when the refrigerant pipe on the outdoor unit 3 side is damaged, a large amount of refrigerant is prevented from leaking outside.

Next, the control of the air conditioner 1 when refrigerant leakage occurs during the heating operation will be described with reference to FIG. During heating operation (S11), it is determined whether or not refrigerant leakage is detected by the refrigerant leakage detection sensors 17 and 18 (S12), and this is repeated until refrigerant leakage is detected. When a refrigerant leak is detected (S12: Yes), it is determined whether the refrigerant has leaked on the outdoor unit side (S13). When the refrigerant leaks on the outdoor unit 3 side (S13: Yes), all the motor-operated valves 25 and the third electromagnetic valves 26 are closed (S14), and the heating operation is stopped (S15). In addition,
Whether the refrigerant has leaked on the outdoor unit side is, for example, whether the refrigerant leak has been detected by the refrigerant leak detection sensor 17 arranged in the outdoor unit 3 or the refrigerant leak detection arranged in the indoor unit 2 It is determined whether the sensor 18 has detected it.

On the other hand, when the refrigerant does not leak on the outdoor unit 3 side (when the refrigerant leaks on the indoor unit 2 side, S13:
No) A branch path in which refrigerant leakage has occurred is specified by each refrigerant leak detection sensor 17 disposed in each of the three indoor units 2, and the motor-operated valve 14 and the electromagnetic valve connected to the branch path in which refrigerant leakage has occurred 15 is closed (S16). And the motor-operated valve 1 connected to the branch path where the refrigerant leakage does not occur
4 and the electromagnetic valve 15 are kept open, and the electromagnetic valve 12 (the closing mechanism downstream in the refrigerant flow direction from the outdoor heat exchanger 13) is closed (S17), and the electromagnetic valve 12 remains closed. The heating operation is continued (S18). As a result, the refrigerant in the refrigerant circuit is prevented from flowing downstream in the refrigerant flow direction from the solenoid valve 12, and the refrigerant in the refrigerant circuit is sequentially stored in the outdoor heat exchanger 13.

And the remaining motor-operated valves 1 connected to the branch path where refrigerant leakage does not occur at a predetermined timing
4 (closing mechanism upstream of the outdoor heat exchanger 13 in the refrigerant flow direction) and the electromagnetic valve 15 are closed (S19), and the heating operation is stopped (S15). The timing for closing the motor-operated valve 14 is preferably after most of the refrigerant in the refrigerant circuit is stored in the outdoor heat exchanger 13 as in the timing for closing the solenoid valve 12 during the cooling operation. .

In the heating operation, the refrigerant mainly stays on the indoor unit 2 side. Therefore, in the control of the air conditioner 1, when the refrigerant leaks on the outdoor unit 3 side, the refrigerant staying on the indoor unit 2 side is confined between the electric valve 14 and the electromagnetic valve 15. Therefore, it is suppressed that the refrigerant on the indoor unit 2 side moves to the outdoor unit 3 side and a large amount of refrigerant leaks outside. Further, in the control of the air conditioner 1, when the refrigerant leaks on the indoor unit 2 side, the branch path where the refrigerant leaks is blocked from the other refrigerant circuits by the motor operated valve 14 and the electromagnetic valve 15. Thus, a large amount of refrigerant is prevented from leaking into the room from the branch path where the refrigerant leakage has occurred.

Next, the control of the air conditioner 1 when the operation of the air conditioner 1 is stopped will be described with reference to FIG. First, during cooling operation or heating operation, it is determined whether or not an operation stop instruction (including automatic stop) has been issued (S21), and this is repeated until an operation stop instruction is received. When there is an operation stop instruction (S21: Yes), it is determined whether or not the cooling operation is being performed (S22).
). When the cooling operation is being performed (S22: Yes), the motor operated valve 14 (the closing mechanism on the downstream side in the refrigerant flow direction from the outdoor heat exchanger 13) is closed (S23), and the cooling operation is continued (S25).
On the other hand, when the cooling operation is not being performed (S22: No), that is, when the heating operation is being performed, the operation is switched to the cooling operation (pump down operation, forced cooling operation) (S24), and steps S23 and S2 are performed.
5 is executed. As a result, the refrigerant in the refrigerant circuit is prevented from flowing downstream (in the indoor unit side) in the refrigerant flow direction from the motor operated valve 14, and the refrigerant in the refrigerant circuit is sequentially stored in the outdoor heat exchanger 13.

Then, at a predetermined timing, the electromagnetic valve 12 (a closing mechanism on the upstream side in the refrigerant flow direction from the outdoor heat exchanger 13) is closed (S26), and the cooling operation is stopped (S27). As a result, when the operation of the air conditioner 1 is stopped, the refrigerant is always stored in the outdoor heat exchanger 13 and the electric valve 14
Since the refrigerant pipe is damaged and the refrigerant leaks while the air conditioner 1 is stopped, a large amount of refrigerant may leak indoors or outdoors. It is suppressed. The timing for closing the solenoid valve 12 is preferably after most of the refrigerant in the refrigerant circuit is stored in the outdoor heat exchanger 13.

<Characteristics of the air conditioner of this embodiment>
In the air conditioner of the present embodiment, in a state where the refrigerant is closed in the outdoor heat exchanger 13,
Since the space between the outdoor heat exchanger 13 and the four-way switching valve 11 can be closed by the electromagnetic valve 12, the compressor 10 and the outdoor heat exchanger 13 do not communicate with each other. Therefore, the refrigerant is the outdoor heat exchanger 1
3, the refrigerant does not move from the outdoor heat exchanger 13 into the compressor 10, so that a large amount of refrigerant and refrigeration oil are not mixed in the compressor 10, and the compressor 10 reliability can be improved.

In the air conditioner of the present embodiment, the electric valve 14 disposed on the indoor heat exchanger 16 side of the outdoor heat exchanger 13 and the electromagnetic disposed on the four-way switching valve 11 side of the outdoor heat exchanger 13. Valve 12
However, since it is arranged inside the outdoor unit 3, the refrigerant can be confined only inside the outdoor unit 3.

In the air conditioner of the present embodiment, the electric valve 14 disposed on the indoor heat exchanger 16 side of the outdoor heat exchanger 13 and the electromagnetic disposed on the four-way switching valve 11 side of the outdoor heat exchanger 13. Valve 12
However, since the motor-operated valve and the solenoid valve are in a closed state when not energized, the motor-operated valve 14 and the solenoid valve 12 are in the closed state even when a power failure occurs in a state where the refrigerant is enclosed in the outdoor heat exchanger 13. As a result, the state in which the refrigerant is confined is maintained.

Moreover, in the air conditioner of this embodiment, the refrigerant circuit has the three branch paths in which the first header 30 and the second header 31 are respectively connected and the indoor heat exchanger 16 is respectively arranged. In the refrigerant circuit in which three indoor heat exchangers 16 are connected to one outdoor heat exchanger 13, the reliability of the compressor 10 can be improved.

In the air conditioner of the present embodiment, the refrigerant circuit is in each of the three branch paths.
Since it has the motor-operated valve 14 arrange | positioned between the 1st header 30 and the indoor heat exchanger 16, and the electromagnetic valve 15 arrange | positioned between the 2nd header 31 and the indoor heat exchanger 16, When there is a refrigerant leak in any of the three branch circuits, only the branch circuit in which the refrigerant leaks out of the three branch circuits can be closed.

Moreover, in the air conditioner of this embodiment, the outdoor units are the first header 30 and the second header 31.
A plurality of pipe connection portions 3a connected to any of the above and to which pipes for indoor unit connection are connected,
Since it has 3b, also in the outdoor unit 3 to which the some indoor unit 2 is connected, the reliability of the compressor 10 can be improved.

Moreover, in the air conditioner of this embodiment, although R32 refrigerant | coolant which has slight flammability is used as a refrigerant | coolant, the reliability of a compressor can be improved also in this case. In addition, R3 as a refrigerant
Even when there is a refrigerant leak when two refrigerants are used, the refrigerant is confined in the outdoor unit 3 (outdoor heat exchanger 13), so there is no problem based on the refrigerant leak.

(Second Embodiment)
6 to 9 show a second embodiment of the present invention. In the air conditioner 1 of the first embodiment, the refrigerant leak detection sensors 17 and 18 are arranged in the indoor unit 2 and the outdoor unit 3 in order to detect refrigerant leakage, whereas the air conditioner of the second embodiment. The machine 101 is greatly different in that the pressure sensor 117 is disposed in the outdoor unit 3. Since other configurations are substantially the same as those in the first embodiment, the description thereof is omitted.

In the air conditioner 101 of the second embodiment, as shown in FIG. 6, the motor-operated valve 14 is disposed between the first header 30 and the liquid side connection portion 3 a in each of the three branch paths. A pressure sensor 117 is disposed between the motor-operated valve 14 and the liquid side connection portion 3a. Therefore, the pressure sensor 117 is disposed closer to the indoor heat exchanger 16 than the motor operated valve 14 in each of the three branch paths.

The pressure sensor 117 detects the refrigerant pressure in the refrigerant circuit (in the branch path), and is connected to the control unit 50 of the air conditioner 1 and transmits a signal indicating the refrigerant pressure in the refrigerant circuit to the control unit. 5
Output for 0. Therefore, in the air conditioner 101 of the present embodiment, the control unit 50 can monitor the refrigerant pressure in the refrigerant circuit (in the branch path), and based on the refrigerant pressure, in the refrigerant circuit (in the branch path). Can detect refrigerant leakage.

The control part 50 of the air conditioner 101 of 2nd Embodiment has a refrigerant | coolant leak detection part. The refrigerant leak detection unit detects refrigerant leak in the refrigerant circuit (in the branch path) based on the output from the pressure sensor 117.

The refrigerant leak detection unit of the present embodiment stores, for example, the refrigerant pressure for various operating states (for example, the temperature of the indoor heat exchanger 16) when there is no refrigerant leak in the refrigerant circuit (branch path). When the refrigerant pressure detected by the pressure sensor 117 is lower than the stored refrigerant pressure by a predetermined amount or more, it is detected that the refrigerant is leaking in the refrigerant circuit (in the branch path).

In the air conditioner 101 of the present embodiment, when refrigerant leakage is detected by the refrigerant leakage detection unit, all the motor-operated valves 14 and the electromagnetic valves 15 of the three branch paths are closed, and the pressure sensors 117 of the respective branch paths. Based on the refrigerant pressure detected by the above, it is detected whether there is a refrigerant leak in any of the three branch paths. For example, among the refrigerant pressures of the three branch paths, there is a branch path that is lower than the refrigerant pressure by a predetermined amount or more with respect to various operating states (for example, the temperature of the indoor heat exchanger 16) when there is no refrigerant leakage in the refrigerant circuit. When it is detected that the refrigerant is leaking in the branch path. On the other hand, among the refrigerant pressures in the three branch paths, there is no branch path that is lower than the refrigerant pressure by a predetermined amount or more with respect to various operating states (for example, the temperature of the indoor heat exchanger 16) when there is no refrigerant leakage in the refrigerant circuit. At this time, since the refrigerant does not leak in the three branch paths, it is detected that the refrigerant is leaking in a portion (in the outdoor unit 3) other than the three branch paths of the refrigerant circuit.

As shown in FIG. 7, the control unit 50 of the air conditioner 101 of the second embodiment includes a compressor 10, a four-way switching valve 11, a solenoid valve 12, three motor-operated valves 14, and three solenoids. The valve 15 and the three pressure sensors 117 are connected to each other. Therefore, the control unit 50 includes the pressure sensor 11.
When the refrigerant leakage in the refrigerant circuit (in the branch path) is detected based on the output from 7, the electromagnetic valve 12, the three motor-operated valves 14, and the three electromagnetic valves 15 can be controlled.

Next, control (flow) of the air conditioner of the present embodiment will be described with reference to FIGS. 8 and 9. Note that the control of the air conditioner when the operation of the air conditioner is stopped is the same as that in the first embodiment, and the description thereof is omitted.

First, the control of the air conditioner when refrigerant leakage occurs during the cooling operation will be described with reference to FIG. During the cooling operation (S201), it is detected whether or not the pressure detected by the pressure sensor 117 is abnormal (S202), and this is repeated until an abnormality is detected. When it is detected that the pressure is abnormal (S202: Yes), the motor-operated valve 14 (the closing mechanism downstream in the refrigerant flow direction from the outdoor heat exchanger 13) is closed (S203), and the motor-operated valve 14 is closed. The cooling operation is continued with the state kept (S204). As a result, the refrigerant in the refrigerant circuit is prevented from flowing downstream (in the indoor unit side) in the refrigerant flow direction from the motor operated valve 14, and the refrigerant in the refrigerant circuit is sequentially stored in the outdoor heat exchanger 13.

Thereafter, the solenoid valve 12 (the closing mechanism on the upstream side in the refrigerant flow direction from the outdoor heat exchanger 13) is closed at a predetermined timing (S205), and the cooling operation is stopped (S206). Therefore,
Since the refrigerant stored in the outdoor heat exchanger 13 is confined between the motor-operated valve 14 and the solenoid valve 12, a large amount of refrigerant is discharged indoors or outdoors when the refrigerant pipe is damaged and refrigerant leaks. To prevent leakage. The timing for closing the solenoid valve 12 is the first timing.
Similarly to the embodiment, it is preferable that most of the refrigerant in the refrigerant circuit is stored in the outdoor heat exchanger 13.

Next, control of the air conditioner when refrigerant leakage occurs during heating operation will be described with reference to FIG. During the heating operation (S211), it is detected whether or not the pressure detected by the pressure sensor 117 is abnormal (S212), and this is repeated until an abnormality is detected. When it is detected that the pressure is abnormal (S212: Yes), it is determined whether or not the refrigerant has leaked on the outdoor unit 3 side (S213). When the refrigerant leaks on the outdoor unit 3 side (S213: Yes), all the motor-operated valves 14 and the electromagnetic valves 15 are closed (S214), and the heating operation is stopped (S215).
.

On the other hand, when the refrigerant does not leak on the outdoor unit 3 side (when the refrigerant leaks on the indoor unit 2 side, S213
: No), each pressure sensor 117 arranged in each branch path identifies the branch path where the refrigerant leaked, and closes the motor-operated valve 14 and the electromagnetic valve 15 connected to the branch path where the refrigerant leak occurred (S216). Then, the solenoid valve 12 (the closing mechanism on the downstream side in the refrigerant flow direction from the outdoor heat exchanger 13) is closed (S217), and the heating operation is continued with the solenoid valve 12 being closed (S218). As a result, the refrigerant in the refrigerant circuit is prevented from flowing downstream in the refrigerant flow direction from the solenoid valve 12, and the refrigerant in the refrigerant circuit is sequentially stored in the outdoor heat exchanger 13.

Then, the remaining motor-operated valve 14 and electromagnetic valve 15 connected to the branch path where refrigerant leakage does not occur at a predetermined timing are closed (S209), and the heating operation is stopped (S215). The timing for closing the motor-operated valve 14 is preferably after most of the refrigerant in the refrigerant circuit is stored in the outdoor heat exchanger 13, similarly to the timing for closing the electromagnetic valve 12 during the cooling operation. .

<Characteristics of the air conditioner of this embodiment>
In the air conditioner of this embodiment, the same effect as the air conditioner of 1st Embodiment is acquired.

Further, in the air conditioner of the present embodiment, the pressure sensor 1 for detecting refrigerant leakage is provided in a plurality of branch paths.
17 is arranged, the refrigerant leakage in the refrigerant circuit can be detected without arranging the refrigerant leakage detection sensor in both the indoor unit 2 and the outdoor unit 3.

Moreover, in the air conditioner of this embodiment, since the pressure sensor 117 is arrange | positioned between the motor operated valve 14 and the solenoid valve 15 in each of three branch passages, refrigerant | coolant leaks in either of three branch circuits. If there is, the branch circuit where the refrigerant leaked can be specified.

(Third embodiment)
10 to 14 show a third embodiment of the present invention. In the air conditioner 1 of the first embodiment, three (a plurality of) indoor heat exchangers are connected to one outdoor heat exchanger 3, whereas in the air conditioner 201 of the third embodiment, The difference is that one indoor heat exchanger is connected to one outdoor heat exchanger 3. Since other configurations are substantially the same as those in the first embodiment, the description thereof is omitted.

As shown in FIG. 10, the air conditioner 201 of the present embodiment includes one indoor unit 2 installed indoors and an outdoor unit 3 installed outdoor. The air conditioner 201 includes a refrigerant circuit configured by the indoor unit 2, the outdoor unit 3, the liquid side pipe 5, and the gas side pipe 6. The refrigerant circuit includes a compressor 10, a four-way switching valve 11, an outdoor heat exchanger 13, and one indoor heat exchanger 1.
6 is connected.

In the refrigerant circuit inside the outdoor unit 3, an electric valve 14 is disposed between the outdoor heat exchanger 13 and the indoor heat exchanger 16. The motor-operated valve 14 can take a plurality of openings corresponding to the open state and the closed state, and is controlled by the control unit 50. The electric valve 14 adjusts the refrigerant flow rate in the branch circuit for flow rate adjustment, and also has a function as an expansion valve.

In the refrigerant circuit inside the outdoor unit 3, an electromagnetic valve 212 is disposed between the outdoor heat exchanger 13 and the motor operated valve 14. The electromagnetic valve 212 can take either an open state or a closed state, and is controlled by the control unit 50. In the present embodiment, the electromagnetic valve 212 corresponds to a first closing mechanism disposed between the indoor heat exchanger 16 and the outdoor heat exchanger 13 in the present invention.

As shown in FIG. 11, the control unit 50 of the air conditioner 201 includes a compressor 10, a four-way switching valve 11, an electromagnetic valve 12, an electric valve 14, an electromagnetic valve 212, and a refrigerant leak detection sensor 17. The refrigerant leakage detection sensor 18 is connected to each other. Therefore, when the refrigerant leak detection sensor 17 or 18 detects the refrigerant leak in the room or outdoors, the controller 50 controls the solenoid valve 12.
And the solenoid valve 212 can be controlled.

Next, the control (flow) of the air conditioner of the present embodiment will be described with reference to FIGS.

First, the control of the air conditioner when refrigerant leakage occurs during the cooling operation will be described with reference to FIG. Hereinafter, the cooling operation includes a dehumidifying operation. During the cooling operation (S301), it is determined whether or not refrigerant leakage has been detected by the refrigerant leakage detection sensors 17 and 18 (S302), and this is repeated until refrigerant leakage is detected. When the refrigerant leakage is detected (S302: Yes), the electromagnetic valve 212 (the closing mechanism on the downstream side in the refrigerant flow direction from the outdoor heat exchanger 13) is closed (S303), and the electromagnetic valve 212 is closed. The cooling operation is continued as it is (S304). As a result, the refrigerant in the refrigerant circuit is prevented from flowing downstream (in the indoor unit side) in the refrigerant flow direction from the solenoid valve 212, and the refrigerant in the refrigerant circuit is sequentially transferred to the outdoor heat exchanger 13.
It is stored in.

Then, during the cooling operation, the electromagnetic valve 12 that is upstream of the outdoor heat exchanger 13 in the refrigerant flow direction is closed at a predetermined timing (S305), and the cooling operation is stopped (S306).
Therefore, since the refrigerant stored in the outdoor heat exchanger 13 is confined between the solenoid valve 212 and the solenoid valve 12, a large amount of refrigerant is stored indoors when the refrigerant pipe is damaged and refrigerant leaks. Or leakage outside the room is prevented. The timing for closing the electromagnetic valve 12 is preferably after most of the refrigerant in the refrigerant circuit is stored in the outdoor heat exchanger 13, as in the first embodiment.

Next, control of the air conditioner when refrigerant leakage occurs during heating operation will be described with reference to FIG. During the heating operation (S311), it is determined whether or not refrigerant leakage has been detected by the refrigerant leakage detection sensors 17 and 18 (S312), and this is repeated until refrigerant leakage is detected. When the refrigerant leakage is detected (S312: Yes), the electromagnetic valve 12 (the closing mechanism on the downstream side in the refrigerant flow direction from the outdoor heat exchanger 13) is closed (S313), and the electromagnetic valve 12 is closed. The heating operation is continued as it is (S314). As a result, the refrigerant in the refrigerant circuit is prevented from flowing downstream from the solenoid valve 12 in the refrigerant flow direction, and the refrigerant in the refrigerant circuit is sequentially transferred to the outdoor heat exchanger 1.
3 is stored.

Then, at a predetermined timing, the electromagnetic valve 212 (a closing mechanism upstream of the outdoor heat exchanger 13 in the refrigerant flow direction) is closed (S315), and the heating operation is stopped (S316). Therefore, since the refrigerant stored in the outdoor heat exchanger 13 is confined between the electromagnetic valve 212 and the electromagnetic valve 12, a large amount of refrigerant leaks indoors or outdoors when refrigerant leakage occurs. Is prevented. The timing for closing the solenoid valve 212 is the solenoid valve 1 during the cooling operation.
Similarly to the timing of closing 2, it is preferable that most of the refrigerant in the refrigerant circuit is stored in the outdoor heat exchanger 13.

Then, during the cooling operation, the electromagnetic valve 12 that is upstream of the outdoor heat exchanger 13 in the refrigerant flow direction is closed at a predetermined timing (S26), and the cooling operation is stopped (S27). As a result, since the refrigerant stored in the outdoor heat exchanger 13 is confined between the solenoid valve 212 and the solenoid valve 12, a large amount of refrigerant is generated when the refrigerant pipe is damaged and refrigerant leaks. Leakage indoors or outdoors is prevented. The timing for closing the solenoid valve 12 is as follows.
It is preferable that most of the refrigerant in the refrigerant circuit is stored in the outdoor heat exchanger 13.

Next, control of the air conditioner when the operation of the air conditioner is stopped will be described with reference to FIG. First, it is determined whether or not there has been an operation stop instruction (including automatic stop) during cooling operation or heating operation (S321), and this is repeated until an operation stop instruction is received. When there is an operation stop instruction (S321: Yes), it is determined whether or not the cooling operation is being performed (S3).
22). When the cooling operation is being performed (S322: Yes), the solenoid valve 212 (outdoor heat exchanger 13).
Is closed (S323), and the cooling operation is continued (S323).
S325). On the other hand, when the cooling operation is not being performed (S322: No), that is, when the heating operation is being performed, the operation is switched to the cooling operation (pump down operation, forced cooling operation) (S324), and steps S323 and S325 are executed. As a result, the refrigerant in the refrigerant circuit is prevented from flowing downstream (in the indoor unit side) in the refrigerant flow direction with respect to the electromagnetic valve 212, and the refrigerant in the refrigerant circuit is sequentially stored in the outdoor heat exchanger 13.

Then, at a predetermined timing, the electromagnetic valve 12 (the closing mechanism on the upstream side in the refrigerant flow direction from the outdoor heat exchanger 13) is closed (S326), and the cooling operation is stopped (S327). As a result, when the operation of the air conditioner is stopped, the refrigerant is always stored in the outdoor heat exchanger 13 and the electromagnetic valve 2
12 and the solenoid valve 12 is confined between the solenoid valve 12 and the refrigerant piping is damaged during the operation stop of the air conditioner, so that a large amount of refrigerant leaks indoors or outdoors. It is suppressed. The timing for closing the solenoid valve 12 is preferably after most of the refrigerant in the refrigerant circuit is stored in the outdoor heat exchanger 13.

<Characteristics of the air conditioner of this embodiment>
In the air conditioner of this embodiment, the same effect as the air conditioner of 1st Embodiment is acquired.

In the air conditioner of the present embodiment, the refrigerant circuit includes the outdoor heat exchanger 13 and the indoor heat exchanger 1.
6 and an electromagnetic valve 212 different from the motor operated valve 14 disposed between the outdoor heat exchanger 13 and the motor operated valve 14. Outdoor heat exchanger 13
Since the electromagnetic valve 212 is used to confine the refrigerant in the outdoor heat exchanger 13, the refrigerant can be reliably confined in the outdoor heat exchanger 13 as compared with the case where the electric valve 14 for flow rate adjustment is used.

As mentioned above, although embodiment of this invention was described based on drawing, it should be thought that a specific structure is not limited to these embodiment. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims for patent, and further includes meanings equivalent to the scope of claims for patent and all modifications within the scope.

For example, in the first to third embodiments described above, the compressor 10, the four-way switching valve 11, the outdoor heat exchanger 13, the first closing mechanism (electric valve 14) for confining the refrigerant in the outdoor heat exchanger 13, and Although the case where the second closing mechanism (electromagnetic valve 12) is arranged inside the outdoor unit 3 has been described, the compressor 10, the four-way switching valve 11, the outdoor heat exchanger 13, and the refrigerant are confined in the outdoor heat exchanger 13. Therefore, the first closing mechanism and the second closing mechanism may not be disposed inside the outdoor unit 3.

In the first to second embodiments described above, the refrigerant circuit has the electric valve 14 for flow rate adjustment disposed between the outdoor heat exchanger 13 and the indoor heat exchanger 16, and the refrigerant is Outdoor heat exchanger 13
The case where the motor-operated valve 14 is used as the first closing mechanism for confining to the electric valve 14 has been described. However, similarly to the third embodiment, an electromagnetic valve different from the motor-operated valve 14 is used as the first closing mechanism. Is disposed between the indoor heat exchanger 16 and the electromagnetic valve, and the solenoid valve transfers the refrigerant to the outdoor heat exchanger 13.
May be used to trap.

Further, in the above-described embodiment, the first closing mechanism (motor valve 14) and the second closing mechanism (electromagnetic valve 12) for confining the refrigerant in the outdoor heat exchanger 13 are configured to be in a closed state when not energized. Although the case where it is performed has been described, it may not be configured to be in a closed state when not energized.

Further, in the first and second embodiments described above, the case where three indoor units 2 are connected to one outdoor unit 3 has been described, but it is connected to one outdoor unit 3. The number of indoor units 2 may be changed.

In the first and second embodiments described above, the refrigerant circuit includes a third closing mechanism disposed between the first header 30 and the indoor heat exchanger 16 in each of the plurality of branch paths, and the second Header 3
Although the case where it has the 4th closing mechanism arrange | positioned between 1 and the indoor heat exchanger 16 was demonstrated, the 3rd closing mechanism and the 4th closing mechanism are arrange | positioned at each of several branch paths. You don't have to.

Further, in the first and second embodiments described above, the case where the pressure sensors 117 for detecting refrigerant leakage are respectively arranged in the plurality of branch paths has been described. However, the pressure for detecting refrigerant leak is set in the plurality of branch paths. Instead of the sensor, a temperature sensor for detecting refrigerant leakage may be provided.

In the first and second embodiments described above, the pressure sensor 117 is disposed between the third closing mechanism (electric valve 14) and the fourth closing mechanism (electromagnetic valve 15) in each of the plurality of branch paths. As described above, the pressure sensor 117 may not be disposed between the third closing mechanism (the electric valve 14) and the fourth closing mechanism (the electromagnetic valve 15) in each of the plurality of branch paths.

In the first and second embodiments described above, the first header 30 and the second header 31 are arranged inside the outdoor unit 3, and the outdoor unit 3 is connected to the first header 30 and the second header 31. The case of having a plurality of pipe connection portions connected to any one of the pipes for connecting the indoor unit has been described, but the first header and the second header are inside the branch unit different from the outdoor unit 3. The branch unit may be connected to the indoor unit 2 and the outdoor unit 3 via the branch unit.

Moreover, although the above-mentioned 1st-3rd embodiment demonstrated the case where R32 refrigerant | coolant was used as a refrigerant | coolant, another refrigerant | coolant may be used.

By utilizing the present invention, it is possible to improve the reliability of the compressor by preventing the refrigerant from moving from the outdoor heat exchanger into the compressor when the refrigerant is confined in the outdoor unit.

DESCRIPTION OF SYMBOLS 1, 101, 201 Air conditioner 2 Indoor unit 3 Outdoor unit 3a, 3b Piping connection part 10 Compressor 11 Four-way switching valve 12 Solenoid valve (2nd closing mechanism)
13 Outdoor heat exchanger 14 Electric valve (first closing mechanism, third closing mechanism)
15 Solenoid valve (fourth closing mechanism)
16 Indoor heat exchanger 17 Refrigerant leak detection sensor 18 Refrigerant leak detection sensor 30 First header 31 Second header 117 Pressure sensor 212 Solenoid valve (first closing mechanism)

Claims (7)

A refrigerant circuit including a compressor, a four-way switching valve, an outdoor heat exchanger, and a plurality of indoor heat exchangers;
The four-way switching valve is
A first state in which the discharge side of the compressor and the outdoor heat exchanger side are communicated and the suction side of the compressor and the indoor heat exchanger side are communicated;
A second state in which the discharge side of the compressor and the indoor heat exchanger side are communicated and the suction side of the compressor and the outdoor heat exchanger side are communicated;
The refrigerant circuit is
A first closing mechanism disposed between the indoor heat exchanger and the outdoor heat exchanger;
A second closing mechanism disposed between the outdoor heat exchanger and the four-way switching valve ;
A first header connected between the outdoor heat exchanger and the plurality of indoor heat exchangers;
A second header connected between the four-way switching valve and the plurality of indoor heat exchangers;
Each of the indoor heat exchangers connects the first header and the second header, respectively
Having a plurality of branched paths arranged;
In each of the plurality of branch paths,
A third closing mechanism disposed between the first header and the indoor heat exchanger;
A fourth closing mechanism disposed between the second header and the indoor heat exchanger;
A refrigerant leakage detection sensor for detecting refrigerant leakage in the outdoor unit or indoor unit,
The compressor, the four-way switching valve, the outdoor heat exchanger, the first closing mechanism, the second closing mechanism, the third closing mechanism, and the fourth closing mechanism are arranged inside the outdoor unit,
The plurality of indoor heat exchangers are respectively disposed inside the plurality of indoor units,
When refrigerant leakage in the outdoor unit is detected during the heating operation, the third closing mechanism and the fourth closing mechanism arranged in all the branch circuits are closed, and the heating operation is stopped.
When refrigerant leakage is detected in the indoor unit during heating operation, the third closing mechanism and the fourth closing mechanism of the branch path where the refrigerant leakage is detected are closed, and the third closing of the branch path where the refrigerant leakage is not detected After the mechanism and the fourth closing mechanism are kept open and the second closing mechanism is closed and the heating operation is continued, the remaining third closing mechanism and the fourth closing mechanism in the branch path where no refrigerant leakage is detected An air conditioner characterized by closing and stopping heating operation . The refrigerant circuit has an electric valve for flow rate adjustment disposed between the outdoor heat exchanger and the indoor heat exchanger,
The air conditioner according to claim 1 , wherein the first closing mechanism is an electromagnetic valve different from the electric valve. The air conditioner according to claim 1 or 2 , wherein the first closing mechanism and the second closing mechanism are configured to be in a closed state when not energized. The air conditioner according to any one of claims 1 to 3, wherein a pressure sensor or a temperature sensor for detecting a refrigerant leak is arranged in each of the plurality of branch paths. The air conditioner according to claim 4 , wherein the pressure sensor or the temperature sensor is disposed between the third closing mechanism and the fourth closing mechanism in each of the plurality of branch paths. . The first header and the second header are disposed inside an outdoor unit,
The outdoor unit claims, characterized in that it comprises a plurality of pipe connecting section pipe is connected to the first is connected to one of the header and the second header and the indoor unit connection 1- 5
The air conditioner according to any one of the above. The air conditioner according to any one of claims 1 to 6 , wherein the refrigerant is an R32 refrigerant.

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