air conditioner

Abstract

To provide an air conditioner that can perform pump-down operation even when its functions are limited due to abnormality detection. [Solution] The air conditioner 1 comprises an outdoor unit, one or more indoor units, and a control device 40 that controls the outdoor unit and one or more indoor units. The control device 40 comprises an abnormality detection unit 41 that detects abnormalities in the outdoor unit and / or one or more indoor units, a function restriction unit 42 that restricts the functions of the outdoor unit and / or one or more indoor units when a predetermined abnormality is detected by the abnormality detection unit 41, and a restriction release unit 43 that releases at least some of the function restrictions imposed by the function restriction unit 42. The restriction release unit 43 determines whether pump-down operation is possible, and if it determines that pump-down operation is possible, it releases at least the function restrictions related to pump-down operation.

Description

Technical Field

[0001] The present disclosure relates to an air conditioner.

Background Art

[0002] In the current air conditioning industry, countermeasures against global warming are essential, and it is necessary to regularly perform maintenance to check for refrigerant leakage and failures in accordance with the fluorocarbon emission control law. In case of an abnormality, unit replacement or the like must be carried out as necessary. When replacing the unit, it is necessary to recover the refrigerant with a refrigerant recovery machine or to recover the refrigerant in the outdoor unit by pump-down operation.

[0003] The pump-down operation is the same as the normal cooling operation except that the liquid side stop valve is closed, and it can simplify the refrigerant recovery work. However, when a predetermined abnormality occurs due to a failure or construction error, the pump-down operation cannot be performed, and the refrigerant recovery by the refrigerant recovery machine is required, which may deteriorate the workability of the construction.

[0004] Patent Document 1 includes a mode setting switch for switching between a normal operation mode and a diagnostic operation mode, and a storage means for storing the diagnostic operation results when operating in the diagnostic operation mode. At least when starting the operation in the normal operation mode for the first time, an operation action according to the diagnostic operation results stored in the storage means is performed, and when starting the operation in the normal operation mode at the end of installation, an air conditioner is disclosed that performs the operation after confirming whether the diagnostic operation has been performed.

[0005] According to this air conditioner, it is possible to surely prevent the omission of the diagnostic operation at the end of installation. If a problem such as incorrect wiring or incorrect piping can be found during the diagnostic operation, the problem part can be corrected on the spot, and the loss during construction can be reduced.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

[0007] However, malfunctions due to manufacturing defects or installation errors can be diverse, and in some cases, abnormalities can occur that prevent normal operation from a safety standpoint. When such abnormalities occur, even if it is necessary to replace the unit, which involves refrigerant recovery, pump-down operation becomes impossible, requiring more extensive work.

[0008] The purpose of this disclosure is to provide an air conditioner that can perform pump-down operation even when its functions are limited in the event of an abnormality detection. [Means for solving the problem]

[0009] The air conditioner disclosed herein is Outdoor unit and One or more indoor units, The system comprises the outdoor unit and a control device for controlling one or more indoor units, The control device is An abnormality detection unit for detecting abnormalities in the outdoor unit and / or one or more indoor units, A function limiting unit that restricts the functions of the outdoor unit and one or more indoor units when a predetermined abnormality is detected by the abnormality detection unit, The system includes a restriction release unit that releases at least a portion of the restrictions on the functions imposed by the aforementioned function restriction unit, The restriction release unit determines whether pump-down operation is possible, and if it determines that pump-down operation is possible, it releases the restrictions on the functions related to pump-down operation. [Brief explanation of the drawing]

[0010] [Figure 1] Figure 1 is a diagram showing the refrigeration cycle of an air conditioner according to one embodiment. [Figure 2] Figure 2 is a block diagram of an air conditioner according to the same embodiment. [Figure 3] Figure 3 is a control flow diagram of the air conditioner when an abnormality is detected according to the same embodiment. [Modes for carrying out the invention]

[0011] (Air conditioner) An air conditioner (refrigeration cycle device) according to one embodiment will be described with reference to Figures 1 and 2. Note that the dimensional ratios in the drawings do not necessarily match the actual dimensional ratios, and the dimensional ratios between the drawings do not necessarily match either. Figure 1 is a configuration diagram showing the refrigeration cycle of the air conditioner 1.

[0012] As shown in Figure 1, the air conditioner 1 is, for example, a room air conditioner, a packaged air conditioner, or a multi-split air conditioner for a building. Figure 1 shows an example where the air conditioner 1 is a packaged air conditioner. The arrows shown in Figure 1 indicate the flow of refrigerant during pump-down operation (cooling operation).

[0013] The air conditioner 1 comprises an outdoor unit 10 and one or more indoor units 20. In the example shown in Figure 1, multiple indoor units are connected to one outdoor unit, but this is not limited to this configuration. For example, multiple outdoor units may be connected to one indoor unit, or one indoor unit may be connected to one outdoor unit.

[0014] The outdoor unit 10 and one or more indoor units 20 are connected by refrigerant piping (liquid connection pipe 31 and gas connection pipe 32). A liquid-side shut-off valve 33 is provided on the outdoor unit 10 side of the liquid connection pipe 31, and a gas-side shut-off valve 34 is provided on the outdoor unit 10 side of the gas connection pipe 32. The liquid-side shut-off valve 33 and the gas-side shut-off valve 34 are, for example, manual valves, and when they are opened after the installation of the air conditioner 1, the refrigerant that was sealed in the outdoor unit 10 at the time of shipment is filled into the indoor unit 20.

[0015] The outdoor unit 10 includes a four-way valve 11, an accumulator 12, a compressor 13, an outdoor heat exchanger 15, an outdoor fan 16, and an outdoor expansion valve 17. The plurality of indoor units 20 each include an indoor heat exchanger 21 (21a to 21d), an indoor fan 22 (22a to 22d), and an indoor expansion valve 23 (23a to 23d).

[0016] The four-way valve 11 switches the refrigerant flow path according to the operation mode of the air conditioner 1. By switching the four-way valve 11, during the cooling operation, as indicated by the solid-line arrow, a refrigeration cycle is formed in which the refrigerant circulates in the order of the accumulator 12, the compressor 13, the outdoor heat exchanger 15 (condenser), the outdoor expansion valve 17, the liquid-side stop valve 33, the indoor expansion valve 23, the indoor heat exchanger 21 (evaporator), and the gas-side stop valve 34.

[0017] Also, by switching the four-way valve 11, during the heating operation, a refrigeration cycle is formed in which the refrigerant circulates in the order of the accumulator 12, the compressor 13, the gas-side stop valve 34, the indoor heat exchanger 21 (condenser), the indoor expansion valve 23, the liquid-side stop valve 33, the outdoor expansion valve 17, and the outdoor heat exchanger 15 (evaporator).

[0018] The accumulator 12 is a container that adjusts the refrigerant discharged from the evaporator to a predetermined refrigerant dryness and discharges it to the compressor 13. Even if there is an excessive inflow of liquid refrigerant during the operation of the air conditioner 1, it supplies the compressor 13 with refrigerant of a predetermined dryness, avoids liquid compression of the compressor 13, and ensures the reliability of the compressor 13. The compressor 13 is, for example, a scroll compressor, a rotary compressor, or a swing compressor.

[0019] The outdoor heat exchanger 15 exchanges heat between the refrigerant and the outdoor air by the outdoor fan 16, acts as a condenser during the cooling operation, and acts as an evaporator during the heating operation. The outdoor expansion valve 17 is composed of, for example, an electronic expansion valve, a thermal expansion valve, etc., and is a valve for adjusting the flow rate of the refrigerant flowing through the indoor heat exchanger 21 and the outdoor heat exchanger 15. The outdoor expansion valve 17 acts as a pressure reducer during the cooling operation.

[0020] The indoor heat exchanger 21 exchanges heat between the refrigerant and the indoor air by means of the indoor fan 22, serves as an evaporator during the cooling operation, and serves as a condenser during the heating operation. The indoor expansion valve 23 is composed of, for example, an electronic expansion valve, a thermal expansion valve, etc., and is a valve for adjusting the flow rate of the refrigerant flowing through the indoor heat exchanger 21. The indoor expansion valve 23 serves as a pressure reducer during the heating operation.

[0021] The cooling operation by the air conditioner 1 is performed based on the following principle. The high-temperature and high-pressure refrigerant gas compressed by the compressor 13 is sent through the four-way valve 11 to the outdoor heat exchanger 15. Then, the refrigerant gas is cooled by heat exchange with the outside air in the outdoor heat exchanger 15 serving as a condenser and becomes a high-pressure liquid refrigerant. The high-pressure liquid refrigerant is decompressed and expanded by the outdoor expansion valve 17 and becomes a gas-liquid two-phase refrigerant (a low-temperature and low-pressure liquid refrigerant containing a small amount of refrigerant gas).

[0022] The gas-liquid two-phase refrigerant decompressed by the outdoor expansion valve 17 is sent to each indoor heat exchanger 21. Then, in the indoor heat exchanger 21 serving as an evaporator, it evaporates by heat exchange with the indoor air,夺取 heat, and becomes a low-temperature and low-pressure gas refrigerant. The low-temperature and low-pressure gas refrigerant enters the accumulator 12 through the four-way valve 11, and the low-temperature and low-pressure liquid refrigerant that has not completely evaporated is separated. The low-temperature and low-pressure gas refrigerant from which the liquid refrigerant has been separated returns to the compressor 13. Thereafter, the same cycle is repeated to continue the cooling.

[0023] The heating operation by the air conditioner 1 is performed in a cycle opposite to that during the cooling operation. The high-temperature and high-pressure refrigerant gas compressed by the compressor 13 is sent to each indoor heat exchanger 21 by switching the four-way valve 11. Then, it gives heat to the indoor air in the indoor heat exchanger 21 serving as a condenser, and thereafter, it夺取 heat from the outside air in the outdoor heat exchanger 15 serving as an evaporator. Such a similar cycle is repeated to continue the heating.

[0024] Pump-down operation by air conditioner 1 is an operation in which all refrigerant from the indoor unit 20 is recovered on the outdoor unit 10 side. Pump-down operation is the above-mentioned cooling operation performed with the liquid-side blocking valve 33 (or outdoor expansion valve 17) closed. The refrigerant flow during pump-down operation is the same as the refrigerant flow during cooling operation (arrow in Figure 1), and the refrigerant liquefied in the outdoor heat exchanger 15, which acts as a condenser, is stored on the outdoor unit 10 side without being supplied to the indoor unit 20 because the liquid-side blocking valve 33 is closed.

[0025] The outdoor unit 10 includes an outdoor pressure sensor 14 for measuring the pressure of the refrigerant inside the outdoor unit 10, an intake temperature sensor (not shown) for measuring the temperature of the refrigerant drawn into the compressor 13 (intake temperature), a discharge temperature sensor (not shown) for detecting the temperature of the refrigerant discharged from the compressor 13 (discharge temperature), a liquid pipe temperature sensor (not shown) for measuring the temperature of the liquid pipe of the outdoor heat exchanger 15, and an outdoor temperature sensor (not shown) for measuring the outdoor temperature.

[0026] The outdoor pressure sensor 14 is a sensor that measures the discharge pressure of the refrigerant discharged from the compressor 13 or the suction pressure of the refrigerant drawn into the compressor 13. In the example shown in Figure 1, the outdoor pressure sensor 14 is installed between the four-way valve 11 and the compressor 13 and measures the discharge pressure, but it is not limited to this. For example, the outdoor pressure sensor 14 may be installed between the accumulator 12 and the compressor 13 and measure the suction pressure. Multiple outdoor pressure sensors 14 may be installed.

[0027] Each indoor unit 20 is equipped with a liquid / gas pipe temperature sensor (not shown) for measuring the temperature of the refrigerant liquid / gas pipes inside the indoor unit 20, an indoor intake temperature sensor (not shown) for measuring the indoor temperature, an indoor outlet temperature sensor (not shown) for measuring the temperature of the air blown out from the indoor unit 20, and a remote control 24 (see Figure 2) for operating the indoor unit 20.

[0028] Figure 2 is a block diagram of the air conditioner 1. As shown in Figures 1 and 2, the air conditioner 1 includes a control device 40 that controls an outdoor unit 10 and one or more indoor units 20. The air conditioner 1 can perform cooling operation, heating operation, and pump-down operation by controlling the outdoor unit 10 and one or more indoor units 20 with the control device 40. The control device 40 is installed in the outdoor unit 10 and / or each indoor unit 20. In Figure 2, the pressure sensor is one or more of the above-described pressure sensors, and the temperature sensor is one or more of the above-described temperature sensors.

[0029] As shown in Figure 2, the control device 40 includes an abnormality detection unit 41 that detects abnormalities in the outdoor unit 10 and / or one or more indoor units 20. The abnormality detection unit 41 can detect, for example, excess or insufficient capacity of the indoor unit 20, electrical wiring errors, abnormal transmission of control signals, failure of the outdoor fan 16 or indoor fan 22, failure of the outdoor expansion valve 17 or indoor expansion valve 23, refrigerant leaks in the outdoor unit 10 or indoor unit 20, failure of the compressor 13, failure of the control board, failure of the temperature sensor, failure of the pressure sensor, etc. Failures of the fans 16 and 22 can be detected, for example, by the difference between the commanded rotation speed and the actual rotation speed. Failures of the expansion valves 17 and 23 can be detected, for example, by the pressure measured by the pressure sensor.

[0030] The control device 40 includes a function restriction unit 42 that restricts the functions of the outdoor unit 10 and one or more indoor units 20 when a predetermined abnormality is detected by the abnormality detection unit 41. The function restriction unit 42 restricts the functions of the air conditioner 1, for example, so that cooling operation, heating operation and pump-down operation cannot be performed. The predetermined abnormality is an abnormality that interferes with air conditioning operation, such as a failure of the fans 16 and 22 or a failure of the expansion valves 17 and 23.

[0031] The control device 40 includes a restriction release unit 43 that releases at least some of the function restrictions imposed by the function restriction unit 42. The restriction release unit 43 determines whether pump-down operation is possible, and if it determines that pump-down operation is possible, it releases at least the function restrictions related to pump-down operation. With this configuration, even if the function of the air conditioner 1 is restricted in the event of an abnormality, pump-down operation can be performed. This eliminates the need for refrigerant recovery work using a refrigerant recovery machine during construction work, for example, improving the workability of the air conditioner 1 during construction. The restriction release unit 43 may also release the function restrictions of the outdoor unit 10 and one or more indoor units 20 (excluding the part where the abnormality occurred) if it determines that pump-down operation is possible. The restriction release unit 43 may also release the function restrictions related to cooling operation and / or heating operation if it determines that pump-down operation is possible.

[0032] The restriction release unit 43 identifies the fault location and determines that pump-down operation is possible if the fault is of a predetermined nature that will not damage any of the components of the air conditioner 1 (excluding the faulty component) by pump-down operation. The predetermined faults include failures of fans 16 and 22, and failures of expansion valves 17 and 23.

[0033] The restriction release unit 43 includes an operating mode switching unit 431. The operating mode switching unit 431 is, for example, a switch provided on the outdoor unit 10 or the indoor unit 20, and when an operator presses the operating mode switching unit 431, the restriction on the functions related to pump-down operation is released when pump-down operation is possible. The operating mode switching unit 431 can be switched between, for example, normal operation mode, fault location diagnosis mode and restriction release mode. If it is determined that pump-down operation is possible in fault location diagnosis mode, it switches to restriction release mode automatically or manually. The operating mode may also be switchable by a remote control 24 or an external device 200 described later.

[0034] Preferably, the control device 40 controls the outdoor unit 10 and one or more indoor units 20 within a predetermined limit range when the restriction on the pump-down operation function is released by the restriction release unit 43. With this configuration, by controlling the outdoor unit 10 and one or more indoor units 20 (each component of the air conditioner 1), it becomes possible to perform pump-down operation within a range in which each component is not damaged.

[0035] Controlling the outdoor unit 10 and one or more indoor units 20 within a predetermined limit range means controlling the load on each component of the outdoor unit 10 and one or more indoor units 20 to be less than during normal operation. For example, the control device 40 controls the frequency of the compressor 13 to be lower than during normal operation, controls the opening of the outdoor expansion valve 17 and / or indoor expansion valve 23 to be smaller (or larger) than during normal operation, and controls the rotational speed of the outdoor fan 16 and / or indoor fan 22 to be smaller (or larger) than during normal operation.

[0036] The control device 40 is connectable to an external device 200, and it is preferable that the restriction release unit 43 releases the restriction on the pump-down operation function when the external device 200 is connected and it is determined that pump-down operation is possible. With such a configuration, pump-down operation can be performed using the external device 200, improving the work efficiency of the worker. The external device 200 is, for example, an inspection device used for maintenance.

[0037] Preferably, the control device 40 can adjust the control values ​​of the outdoor unit 10 and / or one or more indoor units 20 by operating an external device 200 when the restriction on the pump-down operation function is released by the restriction release unit 43. With such a configuration, the operator can adjust the control values ​​depending on the type of failure, and the pump-down operation can be performed within a range that does not damage each component. The control values ​​are, for example, the frequency of the compressor 13, the opening degree of the expansion valves 17 and 23, and the rotational speed of the fans 16 and 22.

[0038] The control device 40 preferably includes a storage unit (not shown) that stores the abnormalities detected by the abnormality detection unit 41. This allows the operator to adjust the control values ​​based on the abnormality history.

[0039] The air conditioner 1 preferably includes a notification unit (not shown) that notifies of abnormalities detected by the abnormality detection unit 41. The notification unit notifies (displays) the details of the abnormality (alarm) on the display screen of the remote control 24, external device 200, information terminal, etc. The notification unit may also be a buzzer that sounds a warning.

[0040] (Control method) Next, we will explain the control method when an abnormality is detected, referring to Figure 3. Figure 3 is a control flow chart for when an abnormality is detected in an air conditioner.

[0041] As shown in Figure 3, first, it is checked whether the air conditioner has stopped operating due to an alarm (anomaly detection) (S101). If the air conditioner has not stopped operating when the alarm (anomaly detection) occurs, normal operation continues (S102).

[0042] If the function is restricted and the air conditioner is stopped when an alarm (abnormality detection) occurs, check if the setting (operation) mode has been switched (S103). If the setting (operation) mode has been switched, start the fault location diagnosis mode (S104). In the fault location diagnosis mode, determine whether the fault location is identified and whether normal operation (pump-down operation) is possible (S105). If it is determined that the fault location is identified and normal operation (pump-down operation) is possible, disable the alarm (release some of the restricted functions) and perform normal operation (pump-down operation) within a predetermined restricted range (S106). If it is determined that the fault location cannot be identified and / or normal operation (pump-down operation) is not possible, maintain the function restrictions and normal operation will not be possible (S107).

[0043] If no setting mode is switched in step S103, check if an external device is connected (S108). If no external device is connected, maintain the function restrictions and disable normal operation (S107). If an external device is connected, start the fault location diagnosis mode (S109).

[0044] In fault location diagnosis mode, the system identifies the fault location and determines whether normal operation (pump-down operation) is possible (S110). If the fault location is identified and it is determined that normal operation (pump-down operation) is possible, the alarm is disabled (some of the restricted functions are released), and the fixed values ​​(control values) are adjusted by an external device to perform normal operation (pump-down operation) (S111). If the fault location cannot be identified and / or it is determined that normal operation (pump-down operation) is not possible, the function restrictions are maintained and normal operation is not possible (S107). [1] As described above, the air conditioner 1 comprises an outdoor unit 10, one or more indoor units 20, and a control device 40 that controls the outdoor unit 10 and one or more indoor units 20. The control device 40 comprises an abnormality detection unit 41 that detects abnormalities in the outdoor unit 10 and / or one or more indoor units 20, a function restriction unit 42 that restricts the functions of the outdoor unit 10 and one or more indoor units 20 when a predetermined abnormality is detected by the abnormality detection unit 41, and a restriction release unit 43 that releases at least some of the function restrictions imposed by the function restriction unit 42. The restriction release unit 43 determines whether pump-down operation is possible and, if it determines that pump-down operation is possible, releases at least the function restrictions related to pump-down operation.

[0045] With this configuration, even if the functions of the outdoor unit 10 and / or indoor unit 20 are limited in the event of an abnormality, pump-down operation can be performed. As a result, for example, refrigerant recovery work using a refrigerant recovery machine becomes unnecessary during installation work, improving the workability of the air conditioner 1 during installation.

[0046] [2] In the air conditioner 1 described in [1] above, it is preferable that the control device 40 controls the outdoor unit 10 and one or more indoor units 20 within a predetermined limit range when the restriction on the function related to pump-down operation is released by the restriction release unit 43.

[0047] With this configuration, by controlling the outdoor unit 10 and one or more indoor units 20 (each component of the air conditioner 1), it becomes possible to perform a pump-down operation within a range that does not damage each component.

[0048] [3] In the air conditioner 1 described in [1] or [2] above, it is preferable that the control device 40 is connectable to an external device 200, and the restriction release unit 43 releases the restriction on the function related to pump-down operation when it determines that the external device 200 is connected and pump-down operation is possible.

[0049] With this configuration, it becomes possible to perform pump-down operation using external equipment 200, improving the efficiency of the worker's construction work.

[0050] [4] In the air conditioner 1 described in [3] above, it is preferable that the control device 40 can adjust the control values ​​of the outdoor unit 10 and / or one or more indoor units 20 by operating an external device 200 when the restriction on the function related to pump-down operation is released by the restriction release unit 43.

[0051] With this configuration, the operator can adjust the control values ​​depending on the type of malfunction, and pump-down operation can be performed within a range where no component is damaged.

[0052] It should be noted that the air conditioner is not limited to the configuration of the embodiment described above, nor is it limited to the effects and benefits described above. Furthermore, it goes without saying that the air conditioner can be modified in various ways without departing from the spirit of the present invention. For example, one or more of the various modifications described above may be arbitrarily selected and adopted in the configuration or method described in the embodiment described above. [Explanation of symbols]

[0053] 1: Air conditioner, 10: Outdoor unit, 11: Four-way valve, 12: Accumulator, 13: Compressor, 14: Outdoor pressure sensor, 15: Outdoor heat exchanger, 16: Outdoor fan, 17: Outdoor expansion valve, 20: Indoor unit, 21, 21a, 21b, 21c, 21d: Indoor heat exchanger, 22, 22a, 22b, 22c, 22d: Indoor fan, 23, 23a, 23b, 23c, 23d: Indoor expansion valve, 24: Remote control, 31: Liquid connection pipe, 32: Gas connection pipe, 33: Liquid side shut-off valve, 34: Gas side shut-off valve, 40: Control device, 41: Anomaly detection unit, 42: Function restriction unit, 43: Restriction release unit, 431: Operating mode switching unit, 200: External device

Claims

1. Outdoor unit and One or more indoor units, The system comprises the outdoor unit and a control device for controlling one or more indoor units, The control device is An abnormality detection unit for detecting abnormalities in the outdoor unit and / or one or more indoor units, A function limiting unit that restricts the functions of the outdoor unit and one or more indoor units when a predetermined abnormality is detected by the abnormality detection unit, The system includes a restriction release unit that releases at least a portion of the restrictions on the functions imposed by the function restriction unit, The aforementioned restriction release unit determines whether pump-down operation is possible, and if it determines that pump-down operation is possible, it releases the restriction on at least the functions related to pump-down operation in the air conditioner.

2. The air conditioner according to claim 1, wherein the control device controls the outdoor unit and one or more indoor units within a predetermined limit range when the restriction on the function related to the pump-down operation is released by the restriction release unit.

3. The control device is connectable to external devices, The air conditioner according to claim 1 or 2, wherein the restriction release unit releases the restriction on the function related to the pump-down operation when the external device is connected and it is determined that the pump-down operation is possible.

4. The air conditioner according to claim 3, wherein the control device can adjust the control values ​​of the outdoor unit and / or one or more indoor units by operating the external device when the restriction on the function related to the pump-down operation is released by the restriction release unit.

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