Air conditioner

Abstract

To provide an air conditioner which can determine a type of abnormal conditions in a more precise manner.SOLUTION: This air conditioner comprises: a first operation valve provided between a compressor and an indoor heat exchanger on a gas pipe; a second operation valve provided between an expansion valve and the indoor heat exchanger on a liquid pipe; a first temperature measurement unit for measuring a temperature of the indoor heat exchanger; a second temperature measurement unit for measuring a temperature of an outdoor heat exchanger; a third temperature measurement unit for measuring an indoor temperature; a fourth temperature measurement unit for measuring an outdoor temperature; and a control device. The control device has: an operation determination unit; a first comparison unit for comparing the outdoor temperature with the temperature of the outdoor heat exchanger in the case of a cooling operation; and a first determination unit for determining a state of each device when the temperature of the outdoor heat exchanger is lower than the outdoor temperature.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present disclosure relates to air conditioning systems. [Background technology]

[0002] In air conditioners that use a refrigeration cycle, abnormalities such as gas low (insufficient amount of refrigerant), blockage of the control valve, and switching failure of the four-way valve can occur. It is known that continuing operation in such a state can cause compressor failure.

[0003] A known technology for determining the type of abnormality in a refrigeration cycle is described in the following Patent Document 1. The device according to the following Patent Document 1 acquires the temperature of either the indoor heat exchanger or the outdoor heat exchanger as an index, and is said to be able to determine various abnormal states based on this index. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2003-090582 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, when the temperature of only one of the indoor heat exchanger and the outdoor heat exchanger is used as an index as described above, the accuracy of identifying an abnormal state may be impaired. For example, there remains a drawback in that it is not possible to distinguish between blockage of the control valve of a gas pipe (piping through which a gas-phase refrigerant flows) and blockage of the control valve of a liquid pipe (piping through which a liquid-phase refrigerant flows).

[0006] The present disclosure has been made to solve the above-mentioned problems, and has an object to provide an air conditioner that is capable of determining the type of abnormal state in more detail. [Means for solving the problem]

[0007] In order to solve the above problems, an air conditioner according to the present disclosure is an air conditioner including an indoor heat exchanger, an outdoor heat exchanger, a gas pipe connecting the indoor heat exchanger and the outdoor heat exchanger and through which a gas-phase refrigerant flows, a compressor arranged on the gas pipe, a liquid pipe connecting the indoor heat exchanger and the outdoor heat exchanger and through which a liquid-phase or two-phase gas-liquid refrigerant flows and which forms a circulation circuit together with the gas pipe, an expansion valve arranged on the liquid pipe, and a four-way valve that switches the flow direction of the refrigerant between a cooling operation and a heating operation, and further including a first operating valve arranged on the gas pipe between the compressor and the indoor heat exchanger, a second operating valve arranged on the liquid pipe between the expansion valve and the indoor heat exchanger, a first temperature measuring unit that measures a temperature of the indoor heat exchanger, and The air conditioning system further includes a second temperature measuring unit that measures the temperature of the outdoor heat exchanger, a third temperature measuring unit that measures the temperature inside the room, a fourth temperature measuring unit that measures the temperature outside the room, and a control device, wherein the control device has an operation discrimination unit that discriminates whether the air conditioning system is in cooling operation or heating operation, a first comparison unit that compares the temperature of the outdoor heat exchanger with the outdoor temperature when the air conditioning system is in cooling operation, and a first discrimination unit that discriminates the state of each device when the temperature of the outdoor heat exchanger is lower than the outdoor temperature, and the first discrimination unit discriminates that a switching failure has occurred in the four-way valve when the temperature of the indoor heat exchanger is equal to or higher than a predetermined first threshold, and discriminates that the first operating valve and the second operating valve are in a blocked state when the temperature of the indoor heat exchanger is less than the first threshold.

[0008] An air conditioner according to the present disclosure includes an indoor heat exchanger, an outdoor heat exchanger, a gas pipe connecting the indoor heat exchanger and the outdoor heat exchanger and through which a gas-phase refrigerant flows, a compressor arranged on the gas pipe, a liquid pipe connecting the indoor heat exchanger and the outdoor heat exchanger and through which a liquid-phase refrigerant flows and which forms a circulation circuit together with the gas pipe, an expansion valve arranged on the liquid pipe, and a four-way valve that switches the flow direction of the refrigerant between a cooling operation and a heating operation, and the air conditioner according to the present disclosure includes a first operating valve arranged on the gas pipe between the compressor and the indoor heat exchanger, a second operating valve arranged on the liquid pipe between the expansion valve and the indoor heat exchanger, and a four-way valve arranged on the indoor heat exchanger. The air conditioning system further includes a first temperature measurement unit that measures the temperature of the outdoor heat exchanger, a second temperature measurement unit that measures the temperature of the outdoor heat exchanger, a third temperature measurement unit that measures the temperature inside the room, a fourth temperature measurement unit that measures the temperature outside the room, and a control device, wherein the control device has an operation discrimination unit that discriminates whether the air conditioning system is in cooling operation or heating operation, a first comparison unit that compares the temperature of the outdoor heat exchanger with the outdoor temperature when the air conditioning system is in heating operation, and a first discrimination unit that discriminates the state of each device when the temperature of the outdoor heat exchanger is higher than the outdoor temperature, and the first discrimination unit discriminates that a switching failure of the four-way valve has occurred when the temperature of the indoor heat exchanger is lower than a predetermined first threshold value. Effect of the Invention

[0009] According to the present disclosure, it is possible to provide an air conditioner that is capable of determining the type of abnormal state in more detail. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a circuit diagram of an air conditioner according to an embodiment of the present disclosure, illustrating a state during cooling operation. [Diagram 2] FIG. 1 is a circuit diagram of an air conditioner according to an embodiment of the present disclosure, illustrating a state during heating operation. [Diagram 3] 4 is a table showing the relationship between various indexes and abnormal states in an air conditioner according to an embodiment of the present disclosure. [Figure 4]FIG. 2 is a functional block diagram of a control device according to an embodiment of the present disclosure. [Diagram 5] 4 is a control flow during cooling operation of the control device according to the embodiment of the present disclosure. [Figure 6] 13 is another control flow during cooling operation and heating operation of the control device according to the embodiment of the present disclosure. [Figure 7] 4 is a control flow during heating operation of the control device according to the embodiment of the present disclosure. [Figure 8] FIG. 2 is a hardware configuration diagram of a control device according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] (Configuration of Air Conditioner 1) An air conditioner 1 according to an embodiment of the present disclosure will be described below with reference to Fig. 1 to Fig. 8. As shown in Fig. 1, the air conditioner 1 includes a refrigeration cycle circuit 10, a first operating valve 20, a second operating valve 30, a first temperature measuring unit 41, a second temperature measuring unit 42, a third temperature measuring unit 43, a fourth temperature measuring unit 44, and a control device 50.

[0012] (Refrigeration cycle circuit 10) The refrigeration cycle circuit 10 includes an indoor heat exchanger 11, an outdoor heat exchanger 12, a gas pipe 13, a compressor 14, a liquid pipe 15, an expansion valve 16, and a four-way valve (not shown).

[0013] The indoor heat exchanger 11 exchanges heat between the indoor air and the refrigerant. The indoor heat exchanger 11 is, for example, a fin-and-tube type or plate type heat exchanger, and the refrigerant flows inside. Although not shown in the figure, it is desirable to provide the indoor heat exchanger 11 with a fan for compressing air into the room.

[0014] The outdoor heat exchanger 12 exchanges heat between the outdoor air and the refrigerant. The outdoor heat exchanger 12 is, for example, a fin-and-tube type or plate type heat exchanger, similar to the indoor heat exchanger 11, and a refrigerant flows inside. Although not shown, it is preferable that the outdoor heat exchanger 12 is provided with a fan for compressing air to the outside of the room.

[0015] (Gas pipe 13, compressor 14) The gas pipe 13 is a pipe that connects the indoor heat exchanger 11 and the outdoor heat exchanger 12, and a gas-phase refrigerant flows inside the gas pipe 13. A compressor 14 is provided on the gas pipe 13. The compressor 14 is, for example, a scroll-type or rotary-type rotating machine, and compresses the gas-phase refrigerant that flows in from the inlet side, raises the pressure to a predetermined level, and then discharges the refrigerant into the gas pipe 13.

[0016] (Liquid pipe 15, expansion valve 16) The liquid pipe 15 is a pipe connecting the indoor heat exchanger 11 and the outdoor heat exchanger 12, and a liquid phase or a gas-liquid two-phase refrigerant flows inside. The liquid pipe 15 forms a circulation circuit together with the gas pipe 13. That is, both ends of the liquid pipe 15 are connected to ends of the indoor heat exchanger 11 and the outdoor heat exchanger 12 that are different from the ends to which the gas pipe 13 is connected. An expansion valve 16 is provided on the liquid pipe 15. The expansion valve 16 is, for example, an electromagnetic expansion valve 16, and has a function of expanding the refrigerant flowing through the liquid pipe 15 to reduce its pressure.

[0017] Although not shown in the figure, the four-way valve is a valve that switches the flow direction of the refrigerant in the gas pipe 13 and the liquid pipe 15 between cooling operation and heating operation. During cooling operation, as shown in Fig. 1, the refrigerant flows through the compressor 14, the outdoor heat exchanger 12, the expansion valve 16, and the indoor heat exchanger 11 in that order. On the other hand, during heating operation, as shown in Fig. 2, the refrigerant flows through the compressor 14, the indoor heat exchanger 11, the expansion valve 16, and the outdoor heat exchanger 12 in that order.

[0018] (Operation of refrigeration cycle circuit 10) Next, the operation of the refrigeration cycle circuit 10 during cooling operation will be described. During cooling operation, the high-temperature, high-pressure gas-phase refrigerant discharged from the compressor 14 flows into the outdoor heat exchanger 12. In the outdoor heat exchanger 12, the refrigerant exchanges heat with the outdoor air, becoming a high-temperature, high-pressure liquid-phase refrigerant. This refrigerant then passes through the expansion valve 16, where it is reduced in pressure, becoming a low-temperature, low-pressure, two-phase liquid-phase refrigerant. This refrigerant then flows into the indoor exchanger and exchanges heat with the indoor air. That is, the low-temperature refrigerant exchanges heat with the high-temperature air in the room, and the indoor air temperature drops. On the other hand, the temperature of the refrigerant rises, becoming a low-temperature, low-pressure gas-phase refrigerant. This refrigerant flows into the compressor 14 again, and the above cycle occurs continuously.

[0019] On the other hand, during heating operation, the high-temperature, high-pressure gas-phase refrigerant discharged from the compressor 14 flows into the indoor heat exchanger 11. In the indoor heat exchanger 11, the refrigerant exchanges heat with the indoor air, becoming a high-temperature, high-pressure liquid-phase refrigerant. This refrigerant then passes through the expansion valve 16, where it is reduced in pressure, becoming a low-temperature, low-pressure two-phase gas-liquid refrigerant. This refrigerant then flows into the outdoor exchanger and exchanges heat with the outdoor air. In other words, the low-temperature refrigerant exchanges heat with the outdoor air, generating a low-temperature, low-pressure gas-phase refrigerant. This refrigerant flows back into the compressor 14, and the above cycle continues.

[0020] (First control valve 20, second control valve 30) The first operating valve 20 is a valve that switches the flow state of the refrigerant in the gas pipe 13. The second operating valve 30 is a valve that switches the flow state of the refrigerant in the liquid pipe 15. As these valves, electromagnetic on-off valves are suitably used.

[0021] (First temperature measuring unit 41 to fourth temperature measuring unit 44) The first temperature measurement unit 41 is a temperature sensor that measures the temperature of the indoor heat exchanger 11. The second temperature measurement unit 42 is a temperature sensor that measures the temperature of the outdoor heat exchanger 12. These sensors directly measure the temperature of the pipes or fins in the heat exchanger, rather than the temperature of the refrigerant in the heat exchanger. The third temperature measurement unit 43 measures the indoor temperature, and the fourth temperature measurement unit 44 measures the outdoor temperature. The first temperature measurement unit 41 to the fourth temperature measurement unit 44 are each electrically connected to a control device 50 described later, and each measurement result is transmitted to the control device 50 as an electrical signal.

[0022] (Control device 50) The control device 50 detects and determines abnormal states of various devices based on the results of measurements by the above-mentioned first temperature measurement unit 41 to fourth temperature measurement unit 44. As shown in Fig. 4, the control device 50 has an operation determination unit 51, a first comparison unit 52, a first determination unit 53, a second comparison unit 54, a second determination unit 55, a third determination unit 56, a fourth determination unit 57, and a memory unit 58. The operation of each functional block will be described below with reference to the flowcharts shown in Figs. 5 to 7.

[0023] (Operation of each function block during cooling operation) The operation discrimination unit 51 discriminates whether the air conditioner 1 is in a cooling operation state or a heating operation state (step S11). First, the operation of each functional block during cooling operation will be described. In the case of cooling operation, the first comparison unit 52 compares the temperature of the outdoor heat exchanger 12 with the outdoor temperature (step S12). When it is determined that the temperature of the outdoor heat exchanger 12 is lower than the outdoor temperature, the first discrimination unit 53 discriminates the state of each device (step S13). Specifically, when the temperature of the indoor heat exchanger 11 is equal to or higher than a predetermined first threshold, the first discrimination unit 53 discriminates that a switching failure of the four-way valve has occurred, and when the temperature of the indoor heat exchanger 11 is lower than the first threshold, the first discrimination unit 53 discriminates that the first operating valve 20 and the second operating valve 30 are in a blocked state.

[0024] That is, the type of abnormal state is determined based on the relationship between the measured temperature of each part and the state of each device shown in Fig. 3. The states 1 to 5 enclosed in circles in Fig. 3 correspond to the numbers 1 to 5 in Figs. 5 to 7.

[0025] When the first comparison unit 52 determines that the temperature of the outdoor heat exchanger 12 is higher than the outdoor temperature, the second comparison unit 54 compares the temperature of the indoor heat exchanger 11 with the indoor temperature (step S14). When the first comparison unit 52 determines that the temperature of the indoor heat exchanger 11 is higher than the indoor temperature in step S14, the second determination unit 55 determines the state of each device by comparing the temperature of the indoor heat exchanger 11 with a second threshold value determined in advance (step S15). Specifically, when the temperature of the indoor heat exchanger 11 is higher than the second threshold value, the second determination unit 55 determines that the first operating valve 20 is in a blocked state, and when the temperature of the indoor heat exchanger 11 is lower than the second threshold value, the second determination unit 55 determines that the first operating valve 20 and the second operating valve 30 are in a blocked state.

[0026] On the other hand, when the first comparison unit 52 judges that the temperature of the outdoor heat exchanger 12 is lower than the outdoor temperature, the third discrimination unit 56 judges an abnormal state (step S16). Specifically, the third discrimination unit 56 judges the state of each device by comparing the temperature of the indoor heat exchanger 11 with a predetermined third threshold value and a fourth threshold value that is higher than the third threshold value. More specifically, when the temperature of the indoor heat exchanger 11 is lower than the third threshold value, the third discrimination unit 56 judges that the second operating valve 30 is in a blocked state or in a normal operating state. When the temperature of the indoor heat exchanger 11 is higher than the third threshold value and lower than the fourth threshold value, it is judged that the amount of refrigerant charged is reduced. Furthermore, when the temperature of the indoor heat exchanger 11 is higher than the fourth threshold value, it is judged that the first operating valve 20 and the second operating valve 30 are in a blocked state.

[0027] When the third discrimination unit 56 judges that the temperature of the indoor heat exchanger 11 is lower than the third threshold, the fourth discrimination unit 57 performs further discrimination. As shown in FIG. 6, the fourth discrimination unit 57 operates the compressor 14 for a predetermined time in a state in which the rotation speed is higher than a predetermined rotation speed threshold (step S21). Thereafter, when the temperature of the indoor heat exchanger 11 is higher than a predetermined fifth threshold, it judges that the second operating valve 30 is in a closed state (step S22). That is, it is determined whether the operation is in a normal operating state or the second operating valve 30 is in a closed state.

[0028] (Operation of each function block during heating operation) On the other hand, during heating operation, each functional block operates as shown in Fig. 7. That is, even if it is determined in step S31 that the operation is heating, the first comparison unit 52 compares the temperature of the outdoor heat exchanger 12 with the outdoor temperature (step S32). The first determination unit 53 determines the state of each device when it is determined that the temperature of the outdoor heat exchanger 12 is higher than the outdoor temperature. Specifically, the first determination unit 53 determines that a switching failure of the four-way valve has occurred when the temperature of the indoor heat exchanger 11 is lower than a predetermined first threshold value (step S33).

[0029] On the other hand, when the first discrimination unit 53 determines that the temperature of the outdoor heat exchanger 12 is lower than the outdoor temperature, the second comparison unit 54 compares the temperature of the indoor heat exchanger 11 with the temperature of the room (step S34). When the temperature of the indoor heat exchanger 11 is determined to be lower than the temperature of the room in step S34, the second discrimination unit 55 discriminates the state of each device by comparing the temperature of the indoor heat exchanger 11 with a second threshold value determined in advance. Specifically, when the temperature of the indoor heat exchanger 11 is higher than the second threshold value, the second discrimination unit 55 discriminates that the first operating valve 20 and the second operating valve 30 are in a closed state, and when the temperature of the indoor heat exchanger 11 is equal to or lower than the second threshold value, the second discrimination unit 55 discriminates that the first operating valve 20 is in a closed state (step S35).

[0030] Furthermore, when the second comparison unit 54 judges that the temperature of the indoor heat exchanger 11 is higher than the temperature of the room, the third discrimination unit 56 discriminates the state of each device. Specifically, the third discrimination unit 56 compares the temperature of the indoor heat exchanger 11 with a predetermined third threshold value and a fourth threshold value that is higher than the third threshold value. When the temperature of the indoor heat exchanger 11 is lower than the third threshold value, the third discrimination unit 56 discriminates that the first operating valve 20 and the second operating valve 30 are in a blocked state. When the temperature of the indoor heat exchanger 11 is higher than the third threshold value and lower than the fourth threshold value, it is determined that the amount of refrigerant charged is reduced. When the temperature of the indoor heat exchanger 11 is higher than the fourth threshold value, it is determined that the second operating valve 30 is in a blocked state or in a normal operating state (step S36).

[0031] When the third discrimination unit 56 determines that the temperature of the indoor heat exchanger 11 is higher than the third threshold, a further discrimination is performed by the fourth discrimination unit 57. As shown in Fig. 6, when the temperature of the indoor heat exchanger 11 is determined to be higher than the fourth threshold, the fourth discrimination unit 57 operates the compressor 14 with the rotation speed higher than a predetermined rotation speed threshold for a predetermined time (step S21). Thereafter, when the temperature of the outdoor heat exchanger 12 is lower than a predetermined sixth threshold, it determines that the second operating valve 30 is in a closed state (step S22).

[0032] (Action and effect) In conventional devices, the temperature of either the indoor heat exchanger 11 or the outdoor heat exchanger 12 is generally obtained as an index, and various abnormal conditions are determined based on this index. However, in this case, there is a risk that the accuracy of determining the abnormal condition may be impaired. For example, there remains a drawback in that it is not possible to distinguish between blockage of the control valve of the gas pipe 13 (piping through which the gas-phase refrigerant flows) and blockage of the control valve of the liquid pipe 15 (piping through which the liquid-phase refrigerant flows). Therefore, the above-mentioned configurations are adopted in this embodiment.

[0033] According to the above configuration, the first discrimination unit 53 can discriminate between a switching failure of the four-way valve and a blockage of the first operation valve 20 and the second operation valve 30 based on the temperature of the indoor heat exchanger 11, the temperature of the outdoor heat exchanger 12, the indoor temperature, and the outdoor temperature. That is, in the cooling operation state, when the switching failure of the four-way valve occurs, the refrigerant flow direction is opposite to the predetermined direction, so that the temperature of the indoor heat exchanger 11 rises and the temperature of the outdoor heat exchanger 12 falls. On the other hand, when the switching of the four-way valve is normal and the first operation valve 20 and the second operation valve 30 are blocked, the temperatures of the indoor heat exchanger 11 and the outdoor heat exchanger 12 do not change. Based on these temperature indicators, it becomes possible to discriminate an abnormal state more precisely. Therefore, when an abnormality occurs, appropriate measures for recovery can be taken immediately. As a result, it becomes possible to operate the air conditioner 1 more stably for a long period of time.

[0034] According to the above configuration, the second determination unit 55 can determine whether the first operating valve 20 is in a closed state or whether the first operating valve 20 and the second operating valve 30 are in a closed state based on the temperature of the indoor heat exchanger 11 and the temperature of the room. That is, when the first operating valve 20 is in a closed state during cooling operation, the refrigerant present in the section between the first operating valve 20 and the inlet of the compressor 14 flows into the indoor heat exchanger 11 and the outdoor heat exchanger 12, but the amount is small, so the pressure rise is small. Therefore, the amount of change in the temperature of the indoor heat exchanger 11 and the outdoor heat exchanger 12 is small. On the other hand, when the first operating valve 20 and the second operating valve 30 are in a closed state, the indoor heat exchanger 11 and the outdoor heat exchanger 12 are blocked from each other, so the amount of change in the temperature of the indoor heat exchanger 11 is extremely small. Also, the refrigerant present in the section between the first operating valve 20 and the inlet of the compressor 14 flows into the indoor heat exchanger 11 and the outdoor heat exchanger 12, but because the amount is small, the pressure rise in the outdoor heat exchanger 12 is small. Therefore, the amount of change in the temperature of the outdoor heat exchanger 12 is small. Based on these temperature indicators, it is possible to more precisely determine an abnormal state. Therefore, when an abnormality occurs, appropriate measures can be taken immediately to restore the system. As a result, it is possible to operate the air conditioner 1 more stably for a long period of time.

[0035] According to the above configuration, based on the temperature of the indoor heat exchanger 11 and the indoor temperature, the third discrimination unit 56 can discriminate whether the second operating valve 30 is in a blocked state or in a normal operation state, whether the amount of refrigerant charged is reduced, and whether the first operating valve 20 and the second operating valve 30 are in a blocked state. That is, in the cooling operation state, when the amount of refrigerant charged is reduced, the flow direction of the refrigerant is the same as during normal operation, so the temperature change of the indoor heat exchanger 11 and the outdoor heat exchanger 12 is small. Also, when the second operating valve 30 is in a blocked state, the pressure of the indoor heat exchanger 11 decreases, so the temperature of the indoor heat exchanger 11 also decreases. On the other hand, the pressure of the outdoor heat exchanger 12 increases, so the temperature of the outdoor heat exchanger 12 increases. Based on these temperature indicators, it is possible to discriminate an abnormal state more precisely. Therefore, when an abnormality occurs, appropriate measures for recovery can be taken immediately. As a result, it is possible to operate the air conditioner 1 more stably for a long period of time.

[0036] According to the above configuration, when the third discrimination unit 56 judges that the temperature of the indoor heat exchanger 11 is lower than the third threshold value, the compressor 14 is operated at a predetermined rotation speed for a certain period of time, and then the fourth discrimination unit 57 judges whether the second operating valve 30 is in a blocked state or in a normal operating state based on a comparison with a further threshold value. That is, when the second operating valve 30 is in a blocked state in a cooling operation state, the pressure of the indoor heat exchanger 11 decreases, so the temperature of the indoor heat exchanger 11 also decreases. On the other hand, the pressure of the outdoor heat exchanger 12 increases, so the temperature of the outdoor heat exchanger 12 increases. Based on these temperature indicators, it is possible to more precisely discriminate an abnormal state. Therefore, when an abnormality occurs, appropriate measures for recovery can be taken immediately. As a result, it is possible to operate the air conditioner 1 more stably for a long period of time.

[0037] According to the above configuration, the first determination unit 53 can determine whether the four-way valve is switched properly based on the temperature of the indoor heat exchanger 11, the temperature of the outdoor heat exchanger 12, the indoor temperature, and the outdoor temperature. That is, in the heating operation state, when the four-way valve is switched properly, the refrigerant flow direction is opposite to the predetermined direction, so that the temperature of the indoor heat exchanger 11 drops and the temperature of the outdoor heat exchanger 12 rises. Based on these temperature indicators, it becomes possible to more precisely determine the abnormal state. Therefore, when an abnormality occurs, appropriate measures for recovery can be taken immediately. As a result, it becomes possible to operate the air conditioner 1 more stably for a long period of time.

[0038] According to the above configuration, the second determination unit 55 can determine whether the first operating valve 20 is in a closed state or whether the first operating valve 20 and the second operating valve 30 are in a closed state based on the temperature of the indoor heat exchanger 11 and the temperature of the room. That is, when the first operating valve 20 is in a closed state during heating operation, all refrigerant flows into the section between the first operating valve 20 and the inlet of the compressor 14, so the pressure of the indoor heat exchanger 11 and the outdoor heat exchanger 12 drops. Therefore, the temperatures of the indoor heat exchanger 11 and the outdoor heat exchanger 12 also drop. On the other hand, when the first operating valve 20 and the second operating valve 30 are in a closed state, the indoor heat exchanger 11 and the outdoor heat exchanger 12 are blocked, so the amount of change in the temperature of the outdoor heat exchanger 12 is extremely small. In addition, all refrigerant flows into the section between the first operating valve 20 and the inlet of the compressor 14, so the pressure of the outdoor heat exchanger 12 drops. Therefore, the temperature of the outdoor heat exchanger 12 also drops. Based on these temperature indices, it becomes possible to more precisely determine an abnormal state. Therefore, when an abnormality occurs, appropriate measures can be taken immediately for recovery. As a result, it becomes possible to operate the air conditioner 1 more stably for a long period of time.

[0039] According to the above configuration, based on the temperature of the indoor heat exchanger 11 and the indoor temperature, the third discrimination unit 56 can discriminate whether the second operating valve 30 is in a blocked state or in a normal operation state, whether the amount of refrigerant charged is reduced, and whether the first operating valve 20 and the second operating valve 30 are in a blocked state. That is, in the heating operation state, when the amount of refrigerant charged is reduced, the flow direction of the refrigerant is the same as in the normal operation state, so the temperature change of the indoor heat exchanger 11 and the outdoor heat exchanger 12 is small. Also, when the second operating valve 30 is in a blocked state, the pressure of the indoor heat exchanger 11 increases, so the temperature of the indoor heat exchanger 11 also increases. On the other hand, the pressure of the outdoor heat exchanger 12 decreases, so the temperature of the outdoor heat exchanger 12 decreases. Based on these temperature indicators, it is possible to discriminate an abnormal state more precisely. Therefore, when an abnormality occurs, appropriate measures for recovery can be taken immediately. As a result, it is possible to operate the air conditioner 1 more stably for a long period of time.

[0040] According to the above configuration, when the third discrimination unit 56 judges that the temperature of the indoor heat exchanger 11 is higher than the fourth threshold, the compressor 14 is operated at a predetermined rotation speed for a certain period of time, and then the fourth discrimination unit 57 discriminates whether the second operating valve 30 is in a blocked state or in a normal operating state based on a comparison with a further threshold. That is, when the second operating valve 30 is in a blocked state in a heating operation state, the pressure of the indoor heat exchanger 11 increases, so the temperature of the indoor heat exchanger 11 also increases. On the other hand, the pressure of the outdoor heat exchanger 12 decreases, so the temperature of the outdoor heat exchanger 12 also decreases. Based on these temperature indicators, it is possible to more precisely discriminate an abnormal state. Therefore, when an abnormality occurs, appropriate measures for recovery can be taken immediately. As a result, it is possible to operate the air conditioner 1 more stably for a long period of time.

[0041] (Other embodiments) Although the embodiment of the present disclosure has been described above in detail with reference to the drawings, the specific configuration is not limited to this embodiment, and design changes and the like within the scope of the gist of the present disclosure are also included. For example, the configuration of the refrigeration cycle circuit 10 is only an example, and it is possible to adopt a configuration including other auxiliary devices such as a receiver not shown. In other words, the above configurations can be applied to any equipment that uses a refrigeration cycle. In other words, regardless of the type of refrigeration cycle device or the type of auxiliary devices, the above configuration can accurately determine an abnormal state while maintaining high versatility.

[0042] It should be noted that the order of the processes performed by the control device 50 in the embodiment of the present disclosure may be changed as long as appropriate processes are performed.

[0043] The storage unit 58 and other storage devices in the embodiment of the present disclosure may be provided anywhere within the range where appropriate information is transmitted and received. Furthermore, the storage unit 58 and other storage devices may each be present in multiple locations within the range where appropriate information is transmitted and received, and data may be stored in a distributed manner.

[0044] The above-mentioned process steps of the control device 50 are stored in the form of a program in a recording medium readable by the computer 200, and the above-mentioned process is performed by the computer 200 reading and executing this program. A specific example of the computer 200 is shown below.

[0045] As shown in FIG. 8, a computer 200 includes a CPU 101, a main memory 102, a storage 103, and an interface 104. For example, the above-mentioned control device 50 is implemented in a computer 200. The operations of the above-mentioned processing units are stored in the storage 103 in the form of a program. The CPU 101 reads the program from the storage 103, loads it in the main memory 102, and executes the above-mentioned processing in accordance with the program. The CPU 101 also secures a storage area in the main memory 102 corresponding to the above-mentioned storage unit 58 in accordance with the program.

[0046] Examples of the storage 103 include a hard disk drive (HDD), a solid state drive (SSD), a magnetic disk, a magneto-optical disk, a compact disc read only memory (CD-ROM), a digital versatile disc read only memory (DVD-ROM), and a semiconductor memory. The storage 103 may be an internal medium directly connected to the bus of the computer 200, or an external medium connected to the computer 200 via the interface 104 or a communication line. In addition, when the program is distributed to the computer 200 via a communication line, the computer 200 that has received the program may expand the program in the main memory 102 and execute the above-mentioned process. The storage 103 is a non-transitory tangible storage medium.

[0047] The program may also realize some of the functions described above. Furthermore, the program may be a file that can realize the functions described above in combination with a program already recorded in computer 200, that is, a so-called difference file (difference program).

[0048] In addition to or instead of the above configuration, a custom LSI (Large Scale Integrated Circuit) such as a PLD (Programmable Logic Device), an ASIC (Application Specific Integrated Circuit), a GPU (Graphics Processing Unit), or a processing device similar thereto may be provided. Examples of PLDs include PAL (Programmable Array Logic), GAL (Generic Array Logic), CPLD (Complex Programmable Logic Device), and FPGA (Field Programmable Gate Array). In this case, some or all of the functions realized by the processor may be realized by the integrated circuit.

[0049] <Additional Notes> The air conditioner 1 described in each embodiment can be understood, for example, as follows.

[0050] (1) An air conditioner 1 according to a first aspect includes an indoor heat exchanger 11, an outdoor heat exchanger 12, a gas pipe 13 that connects the indoor heat exchanger 11 and the outdoor heat exchanger 12 and through which a gas-phase refrigerant flows, a compressor 14 arranged on the gas pipe 13, a liquid pipe 15 that connects the indoor heat exchanger 11 and the outdoor heat exchanger 12 and through which a liquid-phase or two-phase gas-liquid refrigerant flows and forms a circulation circuit together with the gas pipe 13, an expansion valve 16 arranged on the liquid pipe 15, and a four-way valve that switches the flow direction of the refrigerant between a cooling operation and a heating operation. The air conditioner 1 includes a first operating valve 20 arranged on the gas pipe 13 between the compressor 14 and the indoor heat exchanger 11, a second operating valve 30 arranged on the liquid pipe 15 between the expansion valve 16 and the indoor heat exchanger 11, and a first temperature measuring unit 41 that measures the temperature of the indoor heat exchanger 11. The air conditioning system further includes a second temperature measurement unit 42 that measures the temperature of the outdoor heat exchanger 12, a third temperature measurement unit 43 that measures the indoor temperature, a fourth temperature measurement unit 44 that measures the outdoor temperature, and a control device 50. The control device 50 has an operation determination unit 51 that determines whether the air conditioning system 1 is in the cooling operation or the heating operation, a first comparison unit 52 that compares the temperature of the outdoor heat exchanger 12 with the outdoor temperature in the cooling operation, and a first determination unit 53 that determines the state of each device when the temperature of the outdoor heat exchanger 12 is lower than the outdoor temperature. The first determination unit 53 determines that a switching failure has occurred in the four-way valve when the temperature of the indoor heat exchanger 11 is equal to or higher than a predetermined first threshold, and determines that the first operating valve 20 and the second operating valve 30 are in a blocked state when the temperature of the indoor heat exchanger 11 is lower than the first threshold.

[0051] According to the above configuration, the first discrimination unit 53 can discriminate between a switching failure of the four-way valve and blockage of the first operating valve 20 and the second operating valve 30 based on the temperature of the indoor heat exchanger 11, the temperature of the outdoor heat exchanger 12, the indoor temperature, and the outdoor temperature.

[0052] (2) An air conditioner 1 according to a second aspect is the air conditioner 1 of (1), wherein the control device 50 further has a second comparison unit 54 which compares the temperature of the indoor heat exchanger 11 with the temperature of the room when the first comparison unit 52 determines that the temperature of the outdoor heat exchanger 12 is higher than the outdoor temperature, and a second discrimination unit 55 which discriminates the state of each device by comparing the temperature of the indoor heat exchanger 11 with a predetermined second threshold value when the temperature of the indoor heat exchanger 11 is higher than the room temperature, and the second discrimination unit 55 determines that the first operating valve 20 is in a blocked state when the temperature of the indoor heat exchanger 11 is higher than the second threshold value, and determines that the first operating valve 20 and the second operating valve 30 are in a blocked state when the temperature of the indoor heat exchanger 11 is lower than the second threshold value.

[0053] According to the above configuration, the second discrimination unit 55 can discriminate whether the first operating valve 20 is in a blocked state, or whether the first operating valve 20 and the second operating valve 30 are in a blocked state, based on the temperature of the indoor heat exchanger 11 and the temperature inside the room.

[0054] (3) An air conditioner 1 according to a third aspect is the air conditioner 1 of (2), wherein the control device 50 further has a third discrimination unit 56 that, when the second comparison unit 54 determines that the temperature of the indoor heat exchanger 11 is lower than the temperature inside the room, discriminates the state of each device by comparing the temperature of the indoor heat exchanger 11 with a predetermined third threshold value and a fourth threshold value that is higher than the third threshold value, and the third discrimination unit 56 discriminates that the second operating valve 30 is in a blocked state or in a normal operating state when the temperature of the indoor heat exchanger 11 is lower than the third threshold value, discriminates that the amount of refrigerant charged is decreasing when the temperature of the indoor heat exchanger 11 is higher than the third threshold value and lower than the fourth threshold value, and discriminates that the first operating valve 20 and the second operating valve 30 are in a blocked state when the temperature of the indoor heat exchanger 11 is higher than the fourth threshold value.

[0055] According to the above configuration, based on the temperature of the indoor heat exchanger 11 and the room temperature, the third discrimination unit 56 can determine whether the second operating valve 30 is in a blocked state or in normal operation, whether the amount of refrigerant charged is decreasing, and whether the first operating valve 20 and the second operating valve 30 are in a blocked state.

[0056] (4) The air conditioner 1 according to a fourth aspect is the air conditioner 1 of (3), wherein the control device 50 further has a fourth discrimination unit 57 that discriminates whether the second operating valve 30 is in a blocked state or in a normal operating state when the third discrimination unit 56 determines that the temperature of the indoor heat exchanger 11 is lower than the third threshold value, and the fourth discrimination unit 57 operates the compressor 14 for a predetermined time at a rotation speed higher than a predetermined rotation speed threshold value, and discriminates that the second operating valve 30 is in a blocked state when the temperature of the indoor heat exchanger 11 is higher than a predetermined fifth threshold value.

[0057] According to the above configuration, when the third discrimination unit 56 determines that the temperature of the indoor heat exchanger 11 is lower than the third threshold value, the compressor 14 is operated at a predetermined rotation speed for a certain period of time, and then the fourth discrimination unit 57 can discriminate whether the second operating valve 30 is in a blocked state or in a normal operating state based on a comparison with a further threshold value.

[0058] (5) An air conditioner 1 according to a fifth aspect is an air conditioner 1 including an indoor heat exchanger 11, an outdoor heat exchanger 12, a gas pipe 13 connecting the indoor heat exchanger 11 and the outdoor heat exchanger 12 and through which a gas-phase refrigerant flows, a compressor 14 arranged on the gas pipe 13, a liquid pipe 15 connecting the indoor heat exchanger 11 and the outdoor heat exchanger 12 and through which a liquid-phase refrigerant flows and which forms a circulation circuit together with the gas pipe 13, an expansion valve 16 arranged on the liquid pipe 15, and a four-way valve that switches the flow direction of the refrigerant between a cooling operation and a heating operation. The air conditioner 1 includes a first operating valve 20 arranged on the gas pipe 13 between the compressor 14 and the indoor heat exchanger 11, and a second operating valve 30 arranged on the liquid pipe 15 between the expansion valve 16 and the indoor heat exchanger 11. The air conditioning system further includes a first temperature measurement unit 41 that measures the temperature of the indoor heat exchanger 11, a second temperature measurement unit 42 that measures the temperature of the outdoor heat exchanger 12, a third temperature measurement unit 43 that measures the indoor temperature, a fourth temperature measurement unit 44 that measures the outdoor temperature, and a control device 50. The control device 50 has an operation discrimination unit 51 that discriminates whether the air conditioning system 1 is in the cooling operation or the heating operation, a first comparison unit 52 that compares the temperature of the outdoor heat exchanger 12 with the outdoor temperature when the air conditioning system is in the heating operation, and a first discrimination unit 53 that discriminates the state of each device when the temperature of the outdoor heat exchanger 12 is higher than the outdoor temperature. The first discrimination unit 53 discriminates that a switching failure of the four-way valve has occurred when the temperature of the indoor heat exchanger 11 is lower than a predetermined first threshold value.

[0059] According to the above configuration, the first determination unit 53 can determine whether or not the four-way valve has switched, based on the temperature of the indoor heat exchanger 11, the temperature of the outdoor heat exchanger 12, the indoor temperature, and the outdoor temperature.

[0060] (6) An air conditioner 1 according to a sixth aspect is the air conditioner 1 of (5), wherein the control device 50 further has a second comparison unit 54 which compares the temperature of the indoor heat exchanger 11 with the temperature of the room when the first comparison unit 52 determines that the temperature of the outdoor heat exchanger 12 is lower than the outdoor temperature, and a second discrimination unit 55 which discriminates the state of each device by comparing the temperature of the indoor heat exchanger 11 with a predetermined second threshold value when the temperature of the indoor heat exchanger 11 is lower than the room temperature, and the second discrimination unit 55 discriminates that the first operating valve 20 and the second operating valve 30 are in a blocked state when the temperature of the indoor heat exchanger 11 is higher than the second threshold value, and discriminates that the first operating valve 20 is in a blocked state when the temperature of the indoor heat exchanger 11 is lower than the second threshold value.

[0061] According to the above configuration, the second discrimination unit 55 can discriminate whether the first operating valve 20 is in a blocked state, or whether the first operating valve 20 and the second operating valve 30 are in a blocked state, based on the temperature of the indoor heat exchanger 11 and the temperature inside the room.

[0062] (7) An air conditioner 1 according to a seventh aspect is the air conditioner 1 of (6), wherein the control device 50 further has a third discrimination unit 56 that, when the second comparison unit 54 determines that the temperature of the indoor heat exchanger 11 is higher than the temperature inside the room, discriminates the state of each device by comparing the temperature of the indoor heat exchanger 11 with a predetermined third threshold value and a fourth threshold value that is higher than the third threshold value, and the third discrimination unit 56 discriminates that the first operating valve 20 and the second operating valve 30 are in a blocked state when the temperature of the indoor heat exchanger 11 is lower than the third threshold value, discriminates that the amount of refrigerant charged is decreasing when the temperature of the indoor heat exchanger 11 is higher than the third threshold value and lower than the fourth threshold value, and discriminates that the second operating valve 30 is in a blocked state or in a normal operating state when the temperature of the indoor heat exchanger 11 is higher than the fourth threshold value.

[0063] According to the above configuration, based on the temperature of the indoor heat exchanger 11 and the room temperature, the third discrimination unit 56 can determine whether the second operating valve 30 is in a blocked state or in normal operation, whether the amount of refrigerant charged is decreasing, and whether the first operating valve 20 and the second operating valve 30 are in a blocked state.

[0064] (8) An air conditioner 1 according to an eighth aspect is the air conditioner 1 of (7), wherein the control device 50 further has a fourth discrimination unit 57 which discriminates whether the second operating valve 30 is in a blocked state or in a normal operating state when the third discrimination unit 56 determines that the temperature of the indoor heat exchanger 11 is higher than the fourth threshold value, and the fourth discrimination unit 57 operates the compressor 14 for a predetermined time at a rotation speed higher than a predetermined rotation speed threshold value, and discriminates that the second operating valve 30 is in a blocked state when the temperature of the outdoor heat exchanger 12 is lower than a predetermined sixth threshold value.

[0065] According to the above configuration, when the third discrimination unit 56 determines that the temperature of the indoor heat exchanger 11 is higher than the fourth threshold value, the compressor 14 is operated at a predetermined rotation speed for a certain period of time, and then the fourth discrimination unit 57 can discriminate whether the second operating valve 30 is in a blocked state or in a normal operating state based on a comparison with a further threshold value. [Explanation of symbols]

[0066] 1...Air conditioner 10...Refrigeration cycle circuit 11...Indoor heat exchanger 12...Outdoor heat exchanger 13...Gas pipe 14...Compressor 15...Liquid pipe 16...Expansion valve 20...First operating valve 30...Second operating valve 41...First temperature measurement section 42...Second temperature measurement section 43...Third temperature measurement section 44...Fourth temperature measurement section 50...Control device 51...Operation discrimination section 52...First comparison section 53...First discrimination section 54...Second comparison section 55...Second discrimination section 56...Third discrimination section 57...Fourth discrimination section 58...Memory section 101...CPU 102...Main memory 103...Storage 104...Interface 200...Computer

Claims

1. An indoor heat exchanger; An outdoor heat exchanger; a gas pipe connecting the indoor heat exchanger and the outdoor heat exchanger, through which a gas-phase refrigerant flows; a compressor disposed on the gas pipe; a liquid pipe connecting the indoor heat exchanger and the outdoor heat exchanger, through which a liquid-phase or two-phase gas-liquid refrigerant flows, and which forms a circulation circuit together with the gas pipe; an expansion valve provided on the liquid pipe; a four-way valve that switches the flow direction of the refrigerant between a cooling operation and a heating operation; An air conditioning device comprising: a first operating valve provided on the gas pipe between the compressor and the indoor heat exchanger; a second operating valve provided on the liquid pipe between the expansion valve and the indoor heat exchanger; A first temperature measuring unit that measures a temperature of the indoor heat exchanger; A second temperature measuring unit that measures a temperature of the outdoor heat exchanger; A third temperature measuring unit that measures a temperature inside a room; a fourth temperature measuring unit that measures an outdoor temperature; A control device; Further equipped with The control device includes: an operation determination unit that determines whether the air conditioner is in the cooling operation or the heating operation; a first comparison unit that compares a temperature of the outdoor heat exchanger with an outdoor temperature in the case of the cooling operation; a first determination unit that determines a state of each device when the temperature of the outdoor heat exchanger is lower than the outdoor temperature; having The first discrimination unit discriminates that a switching failure of the four-way valve has occurred when the temperature of the indoor heat exchanger is equal to or higher than a predetermined first threshold, and discriminates that the first operating valve and the second operating valve are in a blocked state when the temperature of the indoor heat exchanger is less than the first threshold.

2. The control device includes: a second comparison unit that compares the temperature of the indoor heat exchanger with the temperature of the indoor room when the first comparison unit determines that the temperature of the outdoor heat exchanger is higher than the outdoor temperature; a second determination unit that, when a temperature of the indoor heat exchanger is higher than a temperature inside the room, determines a state of each device by comparing the temperature of the indoor heat exchanger with a predetermined second threshold value; and The air conditioning device according to claim 1, wherein the second discrimination unit discriminates that the first operating valve is in a blocked state when the temperature of the indoor heat exchanger is higher than the second threshold value, and discriminates that the first operating valve and the second operating valve are in a blocked state when the temperature of the indoor heat exchanger is lower than the second threshold value.

3. The control device includes: a third determination unit that, when it is determined by the second comparison unit that the temperature of the indoor heat exchanger is lower than the temperature of the room, determines a state of each device by comparing the temperature of the indoor heat exchanger with a predetermined third threshold value and a fourth threshold value that is higher than the third threshold value; 3. The air conditioning device of claim 2, wherein the third discrimination unit discriminates that the second operating valve is in a blocked state or in a normal operating state when the temperature of the indoor heat exchanger is lower than the third threshold value, discriminates that the amount of refrigerant charged is decreasing when the temperature of the indoor heat exchanger is higher than the third threshold value and lower than the fourth threshold value, and discriminates that the first operating valve and the second operating valve are in a blocked state when the temperature of the indoor heat exchanger is higher than the fourth threshold value.

4. The control device includes: A fourth determination unit that determines whether the second operating valve is in a closed state or in a normal operation state when the third determination unit determines that the temperature of the indoor heat exchanger is lower than the third threshold value, The fourth discrimination unit, 4. The air conditioning apparatus according to claim 3, wherein the compressor is operated for a predetermined time period at a rotation speed higher than a predetermined rotation speed threshold, and the second operating valve is determined to be in a blocked state when the temperature of the indoor heat exchanger is higher than a predetermined fifth threshold.

5. An indoor heat exchanger; An outdoor heat exchanger; a gas pipe connecting the indoor heat exchanger and the outdoor heat exchanger, through which a gas-phase refrigerant flows; a compressor disposed on the gas pipe; a liquid pipe connecting the indoor heat exchanger and the outdoor heat exchanger, through which a liquid phase refrigerant flows, and which forms a circulation circuit together with the gas pipe; an expansion valve provided on the liquid pipe; a four-way valve that switches the flow direction of the refrigerant between a cooling operation and a heating operation; An air conditioning device comprising: a first operating valve provided on the gas pipe between the compressor and the indoor heat exchanger; a second operating valve provided on the liquid pipe between the expansion valve and the indoor heat exchanger; A first temperature measuring unit that measures a temperature of the indoor heat exchanger; A second temperature measuring unit that measures a temperature of the outdoor heat exchanger; A third temperature measuring unit that measures a temperature inside a room; a fourth temperature measuring unit that measures an outdoor temperature; A control device; Further equipped with The control device includes: an operation determination unit that determines whether the air conditioner is in the cooling operation or the heating operation; a first comparison unit that compares a temperature of the outdoor heat exchanger with an outdoor temperature in the case of the heating operation; a first determination unit that determines a state of each device when the temperature of the outdoor heat exchanger is higher than the outdoor temperature; having The first determination unit determines that a switching malfunction has occurred in the four-way valve when a temperature of the indoor heat exchanger is lower than a predetermined first threshold value.

6. The control device includes: a second comparison unit that compares the temperature of the indoor heat exchanger with the temperature of the room when the first comparison unit determines that the temperature of the outdoor heat exchanger is lower than the outdoor temperature; a second determination unit that, when a temperature of the indoor heat exchanger is lower than a temperature inside the room, determines a state of each device by comparing the temperature of the indoor heat exchanger with a predetermined second threshold value; and The air conditioning device according to claim 5, wherein the second discrimination unit discriminates that the first operating valve and the second operating valve are in a blocked state when the temperature of the indoor heat exchanger is higher than the second threshold value, and discriminates that the first operating valve is in a blocked state when the temperature of the indoor heat exchanger is equal to or lower than the second threshold value.

7. The control device includes: a third determination unit that, when it is determined by the second comparison unit that the temperature of the indoor heat exchanger is higher than the temperature of the room, determines a state of each device by comparing the temperature of the indoor heat exchanger with a predetermined third threshold value and a fourth threshold value that is higher than the third threshold value; The air conditioning device of claim 6, wherein the third discrimination unit discriminates that the first operating valve and the second operating valve are in a blocked state when the temperature of the indoor heat exchanger is lower than the third threshold value, discriminates that the amount of refrigerant charged is decreasing when the temperature of the indoor heat exchanger is higher than the third threshold value and lower than the fourth threshold value, and discriminates that the second operating valve is in a blocked state or in a normal operating state when the temperature of the indoor heat exchanger is higher than the fourth threshold value.

8. The control device includes: a fourth determination unit that determines whether the second operating valve is in a closed state or in a normal operation state when the third determination unit determines that the temperature of the indoor heat exchanger is higher than the fourth threshold value; The fourth discrimination unit, 8. The air conditioning system according to claim 7, wherein the compressor is operated for a predetermined time period while the rotation speed of the compressor is higher than a predetermined rotation speed threshold value, and the second operating valve is determined to be in a closed state when the temperature of the outdoor heat exchanger is lower than a predetermined sixth threshold value.

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