WO2022239072A1

WO2022239072A1 - Inspection device and inspection method

Info

Publication number: WO2022239072A1
Application number: PCT/JP2021/017742
Authority: WO
Inventors: 貴大橋川; 康敬落合
Original assignee: 三菱電機株式会社
Priority date: 2021-05-10
Filing date: 2021-05-10
Publication date: 2022-11-17
Also published as: EP4339527A4; CN117203474A; EP4339527A1; JPWO2022239072A1

Abstract

In the present invention, if an outdoor unit of an air conditioner (1) includes a second refrigerant path, which is capable of circulating a refrigerant within the outdoor unit even if the refrigerant circulation in a first refrigerant path for circulating the refrigerant between an indoor unit and the outdoor unit is blocked by the closing of a first valve disposed in the first refrigerant path, a signal transmission unit (121) transmits, to the outdoor unit, an instruction signal instructing the outdoor unit to close a second valve which, upon closing, blocks the refrigerant circulation in the second refrigerant path. A determination unit (123) determines whether the first valve is closed after the instruction signal has been transmitted from the signal transmission unit (121) to the outdoor unit.

Description

Inspection device and inspection method

The present disclosure relates to technology for inspecting whether or not a valve arranged in a refrigerant path of an air conditioner is closed.

A liquid pipe valve and a gas pipe valve are arranged at the entrance and exit of a refrigerant path (hereinafter referred to as a first refrigerant path) for circulating the refrigerant between the outdoor units of the air conditioner. Hereinafter, the liquid pipe valve and the gas pipe valve are collectively referred to as the first valve.
When constructing an air conditioner, it is common to perform a test run of the air conditioner to confirm that there are no defects in the construction work.
The first valve must be opened by an operator when installing the air conditioner. When the first valve is closed, or when the first valve is not fully open, the first refrigerant path is blocked and the refrigerant does not circulate. For this reason, it is assumed that the expected air conditioning performance will not be exhibited. Alternatively, it is assumed that power consumption increases due to an increase in pressure loss.
Further, when the first valve is closed, the pressure difference between the low pressure (intake pressure) and the high pressure (discharge pressure) opens, and the air conditioner is operated by protective control to protect the air conditioner. may stop. When stopping such an air conditioner, it is necessary for the operator to consider the cause of the stop. Moreover, when the operation of the air conditioner continues regardless of the protection control, it is necessary to prevent the operator from overlooking the closed state of the first valve.
As described above, it is required to detect the closed state of the first valve and to let the operator recognize that the first valve is closed, especially during trial operation after installation of the air conditioner.

From this point of view, Patent Document 1 discloses a technique for detecting whether or not the first valve is closed.

Japanese Patent Application Laid-Open No. 2007-107820

Depending on the outdoor unit, there may be a second refrigerant path that allows the refrigerant to circulate inside the outdoor unit even if the circulation of the refrigerant in the first refrigerant path is blocked by closing the first valve. In such an outdoor unit, the refrigerant circulates through the second refrigerant path even when the first valve is closed, so the pressure difference between the low pressure and the high pressure does not open. For this reason, the technique of Patent Document 1 has a problem that it is erroneously determined that the first valve is open even though the first valve is closed.

The main purpose of this disclosure is to solve such problems. More specifically, the main purpose of the present disclosure is to correctly determine whether or not the first valve is closed even when an outdoor unit having a second refrigerant path is used. do.

The inspection device according to the present disclosure is
The circulation of the refrigerant in the first refrigerant path for circulating the refrigerant between the indoor unit and the outdoor unit of the air conditioner is blocked by closing the first valve arranged in the first refrigerant path. When the outdoor unit has a second refrigerant path capable of circulating the refrigerant in the outdoor unit, the second refrigerant path arranged in the second refrigerant path is closed. a signal transmission unit configured to transmit an instruction signal to the outdoor unit to instruct the outdoor unit to close a second valve that blocks circulation of the refrigerant;
and a determination unit that determines whether or not the first valve is closed after the instruction signal is transmitted to the outdoor unit by the signal transmission unit.

According to the present disclosure, even when an outdoor unit having a second refrigerant path is used, it is possible to correctly determine whether the first valve is closed.

1 is a diagram showing a configuration example of an anomaly detection system according to Embodiment 1; FIG. 1 is a diagram showing a configuration example of an air conditioner according to Embodiment 1; FIG. FIG. 2 is a diagram showing a first refrigerant path according to Embodiment 1; FIG. 4 is a diagram showing a second refrigerant path according to Embodiment 1; FIG. 4 is a flowchart showing an operation example of the abnormality determination device according to Embodiment 1; FIG. 5 is a diagram showing a configuration example of an air conditioner according to Embodiment 2; The figure which shows the 1st refrigerant|coolant path|route which concerns on Embodiment 2. FIG. FIG. 8 is a diagram showing a second refrigerant path according to Embodiment 2; The figure which shows the structural example of the air conditioner which concerns on Embodiment 3. FIG. The figure which shows the 1st refrigerant|coolant path|route which concerns on Embodiment 3. FIG. The figure which shows the 2nd refrigerant|coolant path|route which concerns on Embodiment 3. FIG.

An embodiment will be described below with reference to the drawings. In the following description and drawings of the embodiments, the same reference numerals denote the same or corresponding parts.

Embodiment 1.
*** Configuration description ***
FIG. 1 shows a configuration example of an anomaly detection system according to this embodiment.
The abnormality detection system is composed of an air conditioner 1 , an indicator 2 , a display 3 and an abnormality determination device 4 .
The air conditioner 1 , the indicator 2 and the indicator 3 are connected to an abnormality determination device 4 .

The indicator 2 instructs the air conditioner 1 to start trial operation. The indicator 2 is, for example, a remote controller of the air conditioner 1 or a PC (Personal Computer) connected to the air conditioner 1 .

When the closed state of the liquid tube valve 15 and/or the gas tube valve 16, which will be described later, is detected, the indicator 3 displays a message notifying that the liquid tube valve 15 and/or the gas tube valve 16 is in the closed state. indicate. A worker who installs the air conditioner 1 can recognize that the liquid tube valve 15 and/or the gas tube valve 16 is in a closed state from the display of the message on the display device 3 .
The display device 3 is, for example, a remote controller of the air conditioner 1 or a PC connected to the air conditioner 1 .
The indicator 2 and the indicator 3 may be realized by the same device.

The abnormality determination device 4 is a computer. If the indicator 2 and/or the indicator 3 are implemented by a PC, the abnormality determination device 4 may be implemented by the same PC as the indicator 2 and/or the indicator 3 .
The abnormality determination device 4 is composed of a communication device 110 and a processor 120 . Although not shown, the abnormality determination device 4 is assumed to include storage devices such as RAM (Random Access Memory) and HDD (Hard Disk Drive).
The communication device 110 communicates with the air conditioner 1 , the indicator 2 and the display device 3 .
The processor 120 executes a program that implements the functions of the signal transmission unit 121 , the driving data acquisition unit 122 , the determination unit 123 and the notification unit 124 . The processor 120 executes programs and functions as a signal transmission unit 121 , a driving data acquisition unit 122 , a determination unit 123 and a notification unit 124 . Details of the signal transmission unit 121, the driving data acquisition unit 122, the determination unit 123, and the notification unit 124 will be described later.
The abnormality determination device 4 corresponds to an inspection device. Further, the operation procedure of the abnormality determination device 4 corresponds to an inspection method.

FIG. 2 shows a configuration example of the air conditioner 1 .
The air conditioner 1 includes an outdoor unit 10 , an indoor unit 20 , and a connection pipe 30 connecting the outdoor unit 10 and the indoor unit 20 .
FIG. 2 shows a configuration in which a plurality of indoor units 20 are connected to one outdoor unit 10. As shown in FIG. However, the configuration of the air conditioner 1 is not limited to that shown in FIG. The air conditioner 1 may be configured such that one indoor unit 20 is connected to one outdoor unit 10 . Also, the air conditioner 1 may include a plurality of outdoor units 10 .

The outdoor unit 10 includes a compressor 11 , a four-way valve 12 , an outdoor heat exchanger 13 , an outdoor unit fan 14 , a liquid tube valve 15 , a gas tube valve 16 , a subcooling coil 17 and an expansion valve 18 for the subcooling coil.
The indoor unit 20 includes an expansion valve 21 , an indoor heat exchanger 22 and an indoor unit fan 23 .
A refrigerating cycle is configured by annularly connecting the compressor 11, the four-way valve 12, the outdoor heat exchanger 13, the expansion valve 21, and the indoor heat exchanger 22 by refrigerant pipes.
Although not shown in FIG. 2 , the outdoor unit 10 has a communication device that receives an instruction signal from the abnormality determination device 4 . The outdoor unit 10 also has a valve control mechanism that closes the sub-cooling coil expansion valve 18 based on an instruction signal. The instruction signal is a signal that the abnormality determination device 4 instructs the outdoor unit 10 to close the subcooling coil expansion valve 18 .

The compressor 11 compresses a low-temperature, low-pressure refrigerant and converts the low-temperature, low-pressure refrigerant into a high-temperature, high-pressure refrigerant. The compressor 11 is driven by, for example, an inverter, and its capacity (amount of refrigerant discharged per unit time) is controlled.

The four-way valve 12 switches the refrigerant flow according to the operation mode of the air conditioner 1, for example, cooling operation or heating operation.

The outdoor heat exchanger 13 exchanges heat between the refrigerant flowing through the refrigeration cycle and the outdoor air. An outdoor unit fan 14 is adjacent to the outdoor heat exchanger 13 .
The outdoor unit fan 14 blows air to the outdoor heat exchanger 13 . By controlling the number of revolutions of the outdoor unit fan 14, the amount of air blown can be adjusted.

The expansion valve 21 is a valve whose opening can be variably controlled, for example, an electronic expansion valve. By controlling the degree of opening of the expansion valve 21, the amount of pressure reduction of the refrigerant is controlled.

The indoor heat exchanger 22 exchanges heat between the refrigerant flowing through the refrigeration cycle and the indoor air. An indoor unit fan 23 is adjacent to the indoor heat exchanger 22 .
The indoor unit fan 23 blows air to the indoor heat exchanger 22 . By controlling the number of rotations of the indoor unit fan 23, the amount of air blown can be adjusted.

A high pressure sensor 41 and a low pressure sensor 42 are installed before and after the compressor 11 of the outdoor unit 10 . The high pressure sensor 41 measures the high pressure value (discharge pressure value) of the refrigerant in the compressor 11 . The low pressure sensor 42 measures the low pressure value (suction pressure value) of the refrigerant in the compressor 11 .
The high pressure sensor 41 and the low pressure sensor 42 are used when performing control to bring the high pressure and the low pressure closer to target values. Also, the high pressure sensor 41 and the low pressure sensor 42 are used for protective control to avoid damage to the outdoor unit 10 due to an increase in the high pressure and a decrease in the low pressure.

The liquid pipe valve 15 and the gas pipe valve 16 are provided at the connecting portion between the outdoor unit 10 and the connecting pipe 30 .
A worker who performs installation work installs the air conditioner 1 by connecting the outdoor unit 10, the indoor unit 20, and the connecting pipe 30 at the installation location. The liquid pipe valve 15 and the gas pipe valve 16 are closed during shipment and transfer. After connecting the outdoor unit 10, the indoor unit 20 and the connecting pipe 30 at the installation site, the operator opens the liquid pipe valve 15 and the gas pipe valve 16. FIG. When the liquid tube valve 15 and the gas tube valve 16 are opened, circulation of the refrigerant becomes possible.
The liquid pipe valve 15 and the gas pipe valve 16 correspond to the first valve.

During cooling operation, part of the high-pressure refrigerant that has exited the outdoor heat exchanger 13 is decompressed by the subcool coil expansion valve 18, and heat exchange between the decompressed refrigerant and the pre-branched refrigerant is performed by the subcool coil 17. can increase the degree of supercooling. The refrigerant after decompression is returned to the compressor 11 .
The subcool coil expansion valve 18 corresponds to a second valve.

In the outdoor unit 10 shown in FIG. 2, there are two refrigerant paths for circulating the refrigerant.
3 and 4 show two refrigerant paths existing in the outdoor unit 10. FIG.
FIG. 3 shows the first coolant path and FIG. 4 shows the second coolant path.
In the first refrigerant path in FIG. 3, the refrigerant flowing from the indoor unit 20 passes through the gas pipe valve 16, the low pressure sensor 42, the compressor 11, the high pressure sensor 41, the outdoor heat exchanger 13, the subcool coil 17 and the liquid pipe valve. 15 and returned to the indoor unit 20. Refrigerant circulates between the outdoor unit 10 and the indoor unit 20 through the first refrigerant path.
A second refrigerant path in FIG. 4 is a path for recirculating the refrigerant in the outdoor unit 10 . That is, the second refrigerant path is a path passing through the outdoor heat exchanger 13 , the subcooling coil 17 , the subcooling coil expansion valve 18 , the low pressure sensor 42 , the compressor 11 and the high pressure sensor 41 .

If there is no second refrigerant path, if one or both of the liquid pipe valve 15 and the gas pipe valve 16 are closed, both valves are normally open when the compressor 11 is operated. The high-low pressure difference becomes larger than in the case. If the high-low pressure difference exceeds a preset threshold value, it can be determined that the liquid tube valve 15 and/or the gas tube valve 16 may be closed.
However, in the configuration in which the second refrigerant path exists, the expansion valve 18 for the subcooling coil is open even when the circulation of the refrigerant in the first refrigerant path is cut off by closing the liquid tube valve 15 and the gas tube valve 16. , the refrigerant can circulate through the second refrigerant path. Even if the liquid pipe valve 15 and the gas pipe valve 16 are closed, the high-low pressure difference does not increase beyond the threshold when the refrigerant circulates through the second refrigerant path. Therefore, when the sub-cooling coil expansion valve 18 is open, there is a problem that the state of the liquid pipe valve 15 and/or the gas pipe valve 16 cannot be accurately determined.

In order to solve such a problem, the abnormality determination device 4 according to the present embodiment is designed to prevent the liquid pipe valve 15 and/or the gas pipe valve 16 from being closed even when the second refrigerant path exists in the outdoor unit 10. It has a configuration that can correctly determine whether or not
The configuration of the abnormality determination device 4 according to this embodiment will be described below.

The signal transmission unit 121 transmits an instruction signal to the outdoor unit 10 during the test run of the air conditioner 1 . The instruction signal is a signal instructing to close the subcooling coil expansion valve 18 .
The outdoor unit 10 that has received the instruction signal closes the sub-cool coil expansion valve 18 if the sub-cool coil expansion valve 18 is open. Closing the sub-cooling coil expansion valve 18 cuts off circulation of the refrigerant in the second refrigerant circuit.
By shutting off the circulation of the refrigerant in the second refrigerant circuit by closing the sub-cooling coil expansion valve 18, the later-described determination unit 123 can accurately determine the state of the liquid pipe valve 15 and/or the gas pipe valve 16. .

The operating data acquisition unit 122 acquires operating data of the air conditioner 1 . The operating data are, for example, sensor values obtained by sensors installed in the air conditioner 1 . Further, the operating data are control values of the air conditioner 1 . The sensor values include the high pressure value measured by the high pressure sensor 41 and the low pressure value measured by the low pressure sensor 42 . The control values include numerical values such as the frequency of the compressor 11, the rotation speed of the outdoor unit fan 14, and the valve opening degree of the expansion valve 21. FIG.
The operation data acquisition unit 122 acquires the high pressure value measured by the high pressure sensor 41 and the low pressure value measured by the low pressure sensor 42 after the signal transmission unit 121 has transmitted the instruction signal.

The determination unit 123 determines whether or not the liquid tube valve 15 and/or the gas tube valve 16 is closed based on the high pressure value and the low pressure value acquired as the operation data by the operation data acquisition unit 122 . As described above, the determination unit 123 determines that the liquid tube valve 15 and/or the gas tube valve 16 is closed when the high-low pressure difference, which is the pressure difference between the high pressure value and the low pressure value, exceeds a threshold value. do.
Alternatively, the determination unit 123 may determine that the liquid tube valve 15 and/or the gas tube valve 16 are closed when the high pressure exceeds a preset threshold value. Further, the determination unit 123 may determine that the liquid pipe valve 15 and/or the gas pipe valve 16 are closed when the low pressure is below a preset threshold value.
Further, when the air conditioner 1 stops operating due to the activation of the protection function due to an increase in the high pressure or a decrease in the low pressure, the determination unit 123 determines whether the liquid pipe valve 15 and/or the gas pipe valve 16 is closed. It may be determined that there is

When the determination unit 123 determines that the liquid pipe valve 15 and/or the gas pipe valve 16 is in the closed state, the notification unit 124 notifies that the liquid pipe valve 15 and/or the gas pipe valve 16 is in the closed state. Notify workers. Specifically, the notification unit 124 outputs a message to the display device 3 notifying that the liquid pipe valve 15 and/or the gas pipe valve 16 is closed.

***Description of operation***

FIG. 5 shows an operation example of the abnormality determination device 4 according to this embodiment. The operation of the abnormality determination device 4 according to the first embodiment will be described below with reference to the flow of FIG.

When the instruction to start the trial operation of the air conditioner 1 is given by the indicator 2, the trial operation of the air conditioner 1 is started. When the test operation of the air conditioner 1 starts, the operation data acquisition unit 122 acquires the control value as the operation data and recognizes the start of the test operation of the air conditioner 1 .
Then, in step ST01, the signal transmission section 121 transmits an instruction signal to the outdoor unit 10. FIG. Upon receiving the instruction signal, the outdoor unit 10 closes the subcool coil expansion valve 18 based on the instruction signal.

In step ST02, the operating data acquisition unit 122 acquires the high pressure value from the high pressure sensor 41. Further, the operating data acquisition unit 122 acquires the low pressure value from the low pressure sensor 42 . Further, the determination unit 123 calculates a high-low pressure difference ΔP (high-pressure value−low-pressure value), which is the difference between the high-pressure value and the low-pressure value.

Next, in step ST03, the determination unit 123 determines whether or not the high-low pressure difference ΔP exceeds a preset threshold value.
If the high-low pressure difference ΔP exceeds the threshold, the process proceeds to step ST04. On the other hand, if the high-low pressure difference ΔP is equal to or less than the threshold, the process ends.

In step ST04, the determination unit 123 determines that the liquid tube valve 15 and/or the gas tube valve 16 are closed. Then, the notification unit 124 outputs to the display device 3 a message notifying that the liquid pipe valve 15 and/or the gas pipe valve 16 is closed. The display 3 displays a message notifying that the liquid tube valve 15 and/or the gas tube valve 16 are closed.
The operator who saw the message displayed by the display 3 checks the liquid tube valve 15 and the gas tube valve 16, and if the liquid tube valve 15 and/or the gas tube valve 16 is closed, the liquid tube valve 15 and/or perform an operation to open the gas pipe valve 16 .

Note that in step ST03, the determination unit 123 may compare the high pressure value and the threshold instead of comparing the high and low pressure difference ΔP and the threshold as described above. Then, when the high-pressure value exceeds the threshold value, the determination unit 123 determines that the liquid tube valve 15 and/or the gas tube valve 16 are closed. In this case, in step ST02, the operation data acquisition unit 122 only needs to acquire the high pressure value, and the determination unit 123 does not need to calculate the high-low pressure difference ΔP.

Also, regarding step ST03, the determination unit 123 may compare the low pressure value and the threshold instead of comparing the high and low pressure difference ΔP and the threshold as described above. Then, when the low-pressure value is below the threshold value, the determination unit 123 determines that the liquid tube valve 15 and/or the gas tube valve 16 are closed. In this case, in step ST02, the operation data acquisition unit 122 only needs to acquire the low pressure value, and the determination unit 123 does not need to calculate the high-low pressure difference ΔP.

Further, in step ST03, the determination unit 123 causes the air conditioner 1 to operate by activating the protection function due to the increase in the high pressure or the decrease in the low pressure instead of comparing the high and low pressure difference ΔP with the threshold as described above. You may judge whether it stopped. Then, when the operation of the air conditioner 1 stops due to activation of the protection function due to an increase in the high pressure or a decrease in the low pressure, the determination unit 123 determines that the liquid pipe valve 15 and/or the gas pipe valve 16 is closed. can be determined. In this case, in step ST02, the operating data acquisition unit 122 acquires a control value indicating that the operation of the air conditioner 1 should be stopped as the operating data. Then, the determination unit 123 analyzes the control value and recognizes that the operation of the air conditioner 1 has stopped due to activation of the protection function due to an increase in the high pressure or a decrease in the low pressure.

Also, the threshold value to be compared with the high-low pressure difference ΔP may be a fixed value or a variable value. When a variable threshold is used, it is conceivable that the determination unit 123 changes the threshold according to the operating state of the air conditioner 1, such as the frequency of the compressor 11 and the degree of opening of the expansion valve 21 of the indoor unit 20. . By changing the threshold according to the operating state by the determination unit 123, detection accuracy can be improved when the liquid tube valve 15 and/or the gas tube valve 16 is not fully closed.

Further, when the high pressure value is compared with the threshold instead of the high-low pressure difference ΔP, the determination unit 123 uses a variable threshold that changes according to the operating state of the air conditioner 1 as the threshold to be compared with the high pressure value. good too.
Similarly, when the low pressure value is compared with the threshold instead of the high-low pressure difference ΔP, the determination unit 123 uses a variable threshold that changes according to the operating state of the air conditioner 1 as the threshold to be compared with the low pressure value. may

Further, in the above description, it is assumed that the operator who sees the message displayed by the display 3 performs the operation of opening the liquid tube valve 15 and/or the gas tube valve 16 .
Instead of this, the abnormality determination device 4 instructs the outdoor unit 10 to open the liquid tube valve 15 and/or the gas tube valve 16, and automatically opens the liquid tube valve 15 and/or the gas tube valve 16. can be In this case, it is assumed that the outdoor unit 10 includes a valve control mechanism for controlling the opening and closing of the liquid tube valve 15 and the gas tube valve 16 (not shown in FIG. 2).
Specifically, when the determination unit 123 determines that the liquid tube valve 15 and/or the gas tube valve 16 is closed, the signal transmission unit 121 opens the liquid tube valve 15 and/or the gas tube valve 16. An instruction signal instructing to do is transmitted to the outdoor unit 10 . The outdoor unit 10 that has received the instruction signal controls the valve control mechanism to open the liquid pipe valve 15 and/or the gas pipe valve 16 .
By automatically opening the liquid tube valve 15 and/or the gas tube valve 16 in this manner, the work load on the operator can be reduced. In this case, the output of the message to the display device 3 by the notification unit 124 may be omitted.

***Description of the effect of the embodiment***
As described above, in the present embodiment, the abnormality determination device 4 transmits to the outdoor unit 10 an instruction signal instructing the closing of the subcooling coil expansion valve 18, and the outdoor unit 10 closes the subcooling coil expansion valve 18. . Therefore, according to the present embodiment, even if the second refrigerant path exists in the outdoor unit 10, the abnormality determination device 4 determines whether the liquid pipe valve 15 and/or the gas pipe valve 16 is closed. can be determined correctly. As a result, even if the operator forgets to open the liquid pipe valve 15 and/or the gas pipe valve 16 during the installation work, the operator will be notified during the trial operation that the liquid pipe valve 15 and/or the gas pipe valve 16 is closed. can be notified. Even if an abnormal stop occurs during trial operation, the operator can recognize that the cause of the abnormal stop is the closing of the liquid pipe valve 15 and/or the gas pipe valve 16, which leads to a reduction in working time.

Embodiment 2.
In Embodiment 1, the outdoor unit 10 having the configuration shown in FIG. 2, that is, the outdoor unit 10 including the sub-cooling coil 17 and the sub-cooling coil expansion valve 18 and the second refrigerant path shown in FIG. 4 has been described.
In this embodiment, an outdoor unit 10 having another configuration will be described.
In this embodiment, differences from the first embodiment will be mainly described.
Matters not described below are the same as those in the first embodiment.

FIG. 6 shows a configuration example of the air conditioner 1 according to this embodiment.

Since the indoor unit 20 and the connection pipe 30 are the same as those shown in FIG. 2, the description thereof is omitted.
In the outdoor unit 10, the four-way valve 12, the outdoor heat exchanger 13, the outdoor unit fan 14, the liquid pipe valve 15, the gas pipe valve 16, the high pressure sensor 41 and the low pressure sensor 41 are those shown in FIG. is the same as , so the description is omitted.

In the outdoor unit 10 shown in FIG. 6, an injection compressor 111 is arranged instead of the compressor 11 shown in FIG. The injection compressor 111 has a connection port for intermediate pressure in addition to a connection port for discharge pressure and a connection port for suction pressure.
In the outdoor unit 10 shown in FIG. 6, an injection expansion valve 118 is arranged instead of the subcool coil expansion valve 18 shown in FIG. The injection expansion valve 118 adjusts the amount of injection injected from the injection pipe 119 to the intermediate pressure of the injection compressor 111 . The injection expansion valve 118 corresponds to a second valve.
Also, in the outdoor unit 10 shown in FIG. 6, an economizer 117 is arranged instead of the subcooling coil 17 shown in FIG. The economizer 117 recovers the heat of the liquid refrigerant that has flowed out of the outdoor heat exchanger 13 with intermediate-pressure refrigerant.
In the outdoor unit 10 shown in FIG. 6, part of the liquid refrigerant that has flowed out of the outdoor heat exchanger 13 during cooling operation is branched and injected into the intermediate pressure of the injection compressor 111, thereby improving the refrigeration cycle efficiency. .
It is assumed that the outdoor unit 10 has a valve control mechanism (not shown in FIG. 6) that closes the injection expansion valve 118 based on an instruction signal.

Also in the outdoor unit 10 according to the present embodiment, there are the first refrigerant path and the second refrigerant path.
FIG. 7 shows a first refrigerant path according to this embodiment, and FIG. 8 shows a second refrigerant path according to this embodiment.
In the first refrigerant path in FIG. 7, the refrigerant flowing from the indoor unit 20 passes through the gas pipe valve 16, the low pressure sensor 42, the injection compressor 111, the high pressure sensor 41, the outdoor heat exchanger 13, the economizer 117 and the liquid pipe valve. 15 and returned to the indoor unit 20. Refrigerant circulates between the outdoor unit 10 and the indoor unit 20 through the first refrigerant path.
Also in the present embodiment, the second refrigerant path is a path through which the refrigerant circulates inside the outdoor unit 10 . In this embodiment, as shown in FIG. 8, the second refrigerant path passes through the outdoor heat exchanger 13, the economizer 117, the injection expansion valve 118, the injection pipe 119, the injection compressor 111, and the high pressure sensor 41. is the route.

In the outdoor unit 10 according to the present embodiment as well, if the injection expansion valve 118 is open even if the circulation of the refrigerant in the first refrigerant path is blocked by closing the liquid pipe valve 15 and the gas pipe valve 16, The coolant can circulate through the second coolant path. Even if the liquid pipe valve 15 and the gas pipe valve 16 are closed, the high-low pressure difference does not increase beyond the threshold when the refrigerant circulates through the second refrigerant path. Therefore, when the injection expansion valve 118 is open, there is a problem that the state of the liquid tube valve 15 and/or the gas tube valve 16 cannot be accurately determined.

The configuration of the abnormality determination device 4 according to this embodiment is as shown in FIG.
Also in the present embodiment, in order to solve the above problem, the signal transmission unit 121 transmits to the outdoor unit 10 an instruction signal instructing the injection expansion valve 118 to close.
The outdoor unit 10 that has received the instruction signal closes the injection expansion valve 118 if the injection expansion valve 118 is open. Closing the injection expansion valve 118 cuts off the recirculation of the refrigerant in the second refrigerant circuit.
Also in the present embodiment, the determination unit 123 can accurately determine the state of the liquid pipe valve 15 and/or the gas pipe valve 16 by blocking the circulation of the refrigerant in the second refrigerant circuit by closing the injection expansion valve 118. can do.

An operation example of the abnormality determination device 4 according to the present embodiment is as shown in FIG. Therefore, detailed description of the operation of the abnormality determination device 4 according to the present embodiment will be omitted.

Thus, even when the outdoor unit 10 includes the second refrigerant path having the configuration shown in FIG. can be judged correctly.

Embodiment 3.
In this embodiment, an outdoor unit 10 having a configuration different from that of the first and second embodiments will be described.
In this embodiment, differences from the first embodiment will be mainly described.
Matters not described below are the same as those in the first embodiment.

FIG. 9 shows a configuration example of the air conditioner 1 according to this embodiment.

Since the indoor unit 20 and the connection pipe 30 are the same as those shown in FIG. 2, the description thereof is omitted.
Further, in the outdoor unit 10, the compressor 11, the four-way valve 12, the outdoor heat exchanger 13, the outdoor unit fan 14, the liquid pipe valve 15, the gas pipe valve 16, the high pressure sensor 41 and the low pressure sensor 42 are arranged as shown in FIG. Since it is the same as that shown in , the description is omitted.

The outdoor unit 10 according to this embodiment is provided with an oil separator 51 , a capillary tube 52 and an oil return valve 53 .
The oil separator 51 separates refrigerating machine oil contained in the refrigerant discharged from the compressor 11 .
The capillary tube 52 functions as a flow resistance that appropriately adjusts the flow rate of the refrigerating machine oil and refrigerant returned from the oil separator 51 to the suction side of the compressor 11 .
The oil return valve 53 is opened while the compressor 11 is running. The oil return valve 53 corresponds to a second valve.
Refrigerating machine oil discharged from the compressor 11 is quickly recovered to the compressor 11 by an oil return path composed of the oil separator 51 , the capillary tube 52 and the oil return valve 53 . As a result, it is possible to prevent refrigerating machine oil from flowing out of the outdoor unit 10 and being distributed throughout the refrigerant path, thereby preventing lubrication failure of the compressor 11 . As a result, a highly reliable refrigeration cycle can be realized.
It is assumed that the outdoor unit 10 has a valve control mechanism (not shown in FIG. 9) that closes the oil return valve 53 based on an instruction signal.

Also in the outdoor unit 10 according to the present embodiment, there are the first refrigerant path and the second refrigerant path.
FIG. 10 shows a first refrigerant path according to this embodiment, and FIG. 11 shows a second refrigerant path according to this embodiment.
10, the refrigerant flowing from the indoor unit 20 passes through the gas pipe valve 16, the low pressure sensor 42, the compressor 11, the high pressure sensor 41, the oil separator 51, the outdoor heat exchanger 13 and the liquid pipe. It is returned to the indoor unit 20 via the valve 15 . Refrigerant circulates between the outdoor unit 10 and the indoor unit 20 through the first refrigerant path.
Also in the present embodiment, the second refrigerant path is a path through which the refrigerant circulates inside the outdoor unit 10 . In this embodiment, as shown in FIG. 11, the second refrigerant path is a path passing through the compressor 11, the high pressure sensor 41, the oil separator 51, the capillary tube 52, the oil return valve 53, and the low pressure sensor 42. is.

Also in the outdoor unit 10 according to the present embodiment, even if the circulation of the refrigerant in the first refrigerant path is blocked by closing the liquid tube valve 15 and the gas tube valve 16, if the oil return valve 53 is open, the refrigerant can circulate through the second refrigerant path. Even if the liquid pipe valve 15 and the gas pipe valve 16 are closed, the high-low pressure difference does not increase beyond the threshold when the refrigerant circulates through the second refrigerant path. Therefore, when the oil return valve 53 is open, there is a problem that the states of the liquid tube valve 15 and/or the gas tube valve 16 cannot be accurately determined.

The configuration of the abnormality determination device 4 according to this embodiment is as shown in FIG.
Also in the present embodiment, in order to solve the above problem, the signal transmission section 121 transmits an instruction signal to the outdoor unit 10 to instruct the oil return valve 53 to be closed.
The outdoor unit 10 that has received the instruction signal closes the oil return valve 53 if the oil return valve 53 is open. By closing the oil return valve 53, circulation of the refrigerant in the second refrigerant circuit is interrupted.
Also in the present embodiment, the determining unit 123 can accurately determine the state of the liquid tube valve 15 and/or the gas tube valve 16 by blocking the circulation of the refrigerant in the second refrigerant circuit by closing the oil return valve 53. be able to.

*** Supplementary explanation of hardware configuration ***
Finally, a supplementary description of the hardware configuration of the abnormality determination device 4 will be given.
The processor 120 shown in FIG. 1 is an IC (Integrated Circuit) that performs processing.
The processor 120 is a CPU (Central Processing Unit), a DSP (Digital Signal Processor), or the like.
The communication device 110 shown in FIG. 1 is an electronic circuit that performs data communication processing.
The communication device 110 is, for example, a communication chip or a NIC (Network Interface Card).

A storage device (not shown in FIG. 1) also stores an OS (Operating System).
At least part of the OS is executed by the processor 120 .
While executing at least part of the OS, the processor 120 executes a program that implements the functions of the signal transmission unit 121, the driving data acquisition unit 122, the determination unit 123, and the notification unit 124.
Task management, memory management, file management, communication control, etc. are performed by the processor 120 executing the OS.
In addition, at least one of information, data, signal values, and variable values indicating the processing results of the signal transmission unit 121, the driving data acquisition unit 122, the determination unit 123, and the notification unit 124 is stored in a storage device, a register in the processor 120, and Stored in at least one of the cache memories.
A program that realizes the functions of the signal transmission unit 121, the driving data acquisition unit 122, the determination unit 123, and the notification unit 124 is compatible with magnetic discs, flexible discs, optical discs, compact discs, Blu-ray (registered trademark) discs, DVDs, and the like. It may be stored in a transport recording medium. Then, a portable recording medium storing a program for realizing the functions of the signal transmission unit 121, the operation data acquisition unit 122, the determination unit 123, and the notification unit 124 may be distributed.

Further, the “units” of the signal transmission unit 121, the driving data acquisition unit 122, the determination unit 123, and the notification unit 124 may be read as “circuit”, “process”, “procedure”, “processing”, or “circuitry”. good.
Further, the abnormality determination device 4 may be realized by a processing circuit. The processing circuits are, for example, logic ICs (Integrated Circuits), GAs (Gate Arrays), ASICs (Application Specific Integrated Circuits), and FPGAs (Field-Programmable Gate Arrays).
In this case, the signal transmission unit 121, the driving data acquisition unit 122, the determination unit 123, and the notification unit 124 are each realized as part of the processing circuit.
In this specification, the general concept of processors and processing circuits is referred to as "processing circuitry."
Thus, processors and processing circuitry are each examples of "processing circuitry."

Although the first to third embodiments have been described above, two or more of these embodiments may be combined for implementation.
Alternatively, one of these embodiments may be partially implemented.
Alternatively, two or more of these embodiments may be partially combined for implementation.
Also, the configurations and procedures described in these embodiments may be changed as necessary.

1 air conditioner, 2 indicator, 3 indicator, 4 abnormality determination device, 10 outdoor unit, 11 compressor, 12 four-way valve, 13 outdoor heat exchanger, 14 outdoor unit fan, 15 liquid pipe valve, 16 gas pipe valve , 17 subcool coil, 18 subcool coil expansion valve, 20 indoor unit, 21 expansion valve, 22 indoor heat exchanger, 23 indoor unit fan, 30 connection pipe, 41 high pressure sensor, 42 low pressure sensor, 51 oil separator, 52 capillary tube, 53 oil return valve, 110 communication device, 111 injection compressor, 117 economizer, 118 injection expansion valve, 119 injection pipe, 120 processor, 121 signal transmitter, 122 operation data acquisition unit, 123 determination unit, 124 Notification department.

Claims

The circulation of the refrigerant in the first refrigerant path for circulating the refrigerant between the indoor unit and the outdoor unit of the air conditioner is blocked by closing the first valve arranged in the first refrigerant path. When the outdoor unit has a second refrigerant path capable of circulating the refrigerant in the outdoor unit, the second refrigerant path arranged in the second refrigerant path is closed. a signal transmission unit configured to transmit an instruction signal to the outdoor unit to instruct the outdoor unit to close a second valve that blocks circulation of the refrigerant;
and a determination unit that determines whether or not the first valve is closed after the instruction signal is transmitted to the outdoor unit by the signal transmission unit.
The determination unit is
2. The inspection device according to claim 1, wherein whether or not the first valve is closed is determined using at least one of a high pressure value and a low pressure value of the refrigerant in a compressor included in the outdoor unit. .
The determination unit is
Any one of the high pressure value, the low pressure value, and the pressure difference between the high pressure value and the low pressure value is compared with a variable threshold whose value changes according to the operating state of the air conditioner. 3. The inspection apparatus according to claim 2, wherein the first valve is closed.
The signal transmission unit is
2. The inspection device according to claim 1, wherein an instruction signal instructing the outdoor unit to open the first valve is transmitted when the determination unit determines that the first valve is closed.
The inspection device according to claim 1, wherein the second refrigerant path includes a subcooling coil, and is a refrigerant path in which an expansion valve for the subcooling coil is arranged as the second valve.
The second refrigerant path is a refrigerant circuit that includes an economizer and an injection expansion valve that adjusts the amount of injection injected into the injection compressor included in the outdoor unit. The inspection device according to claim 1.
The second refrigerant path includes an oil separator for separating refrigerating machine oil contained in the refrigerant discharged from the compressor included in the outdoor unit; 2. The inspection apparatus according to claim 1, wherein the refrigerant circuit includes a capillary tube for adjusting the flow rate of refrigerant, and an oil return valve for returning the refrigerant oil and the refrigerant to the compressor as the second valve. .
The circulation of the refrigerant in the first refrigerant path for circulating the refrigerant between the indoor unit and the outdoor unit of the air conditioner is blocked by closing the first valve arranged in the first refrigerant path. When the outdoor unit has a second refrigerant path capable of circulating the refrigerant in the outdoor unit, the second refrigerant path arranged in the second refrigerant path is closed. A computer sends an instruction signal to the outdoor unit to instruct the outdoor unit to close a second valve that blocks circulation of the refrigerant;
The inspection method, wherein the computer determines whether or not the first valve is closed after the instruction signal is transmitted to the outdoor unit.