JP2021025726A - Refrigerant leakage detection system - Google Patents

Abstract

To provide a refrigerant leakage detection system capable of accurately detecting refrigerant leakage in an air conditioner.SOLUTION: A refrigerant leakage detection system includes an air conditioner, a server connectable with the air conditioner through an Internet line, and a data storage device for storing an operating state data of the air conditioner transmitted to the server from the air conditioner. The operating state data includes at least an expansion valve opening in the air conditioner. The server calculates a maximum expansion valve opening of each day for a prescribed period (S1-S3) by using the expansion valve openings stored in the data storage device, and detects refrigerant leakage (S6) when the calculated maximum expansion valve opening tends to rise (YES in S4), and days when the maximum expansion valve opening is a first threshold value or more continue (YES in S5).SELECTED DRAWING: Figure 3

Description

The present invention relates to a refrigerant leakage detection system that detects refrigerant leakage in an air conditioner.

If a refrigerant leaks in the air conditioner, the air conditioner will not operate normally, and the user will contact the manufacturer to request repair. In such a case, it is common for the serviceman of the manufacturer to visit the user's house to identify the cause of the failure (refrigerant leakage, etc.), and then revisit with the parts necessary for repair and perform the repair. Is. However, such a method has a problem that it takes a relatively long time from the user's request for repair to the actual repair. If a refrigerant leak can be detected before the serviceman visits, repairs can be performed at the serviceman's first visit.

Patent Document 1 discloses a refrigerant leak detection system in which a plurality of air conditioners and a center server are connected via an Internet line. This refrigerant leakage detection system can automatically detect refrigerant leakage from the past operating state data stored in the center server. Further, in this refrigerant leakage detection system, when the accumulated operating state data is insufficient in the first air conditioner for detecting the refrigerant leakage, the first air conditioner and the equipment configuration and environmental conditions Refrigerant leakage is detected by referring to the operating state data of the second air conditioner in which at least one of the above is similar.

Japanese Patent No. 4826117

However, in the refrigerant leakage detection system of Patent Document 1, accurate detection cannot be performed in an air conditioner for detecting refrigerant leakage when the amount of accumulated operation state data is small. Further, in such a case, since the operating state data of other air conditioners having similar equipment configurations or environmental conditions is used, the detection accuracy may decrease.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a refrigerant leakage detection system capable of accurately detecting refrigerant leakage in an air conditioner.

In order to solve the above problems, the refrigerant leakage detection system according to one aspect of the present invention is transmitted from the air conditioner to the server, a server that can be connected to the air conditioner through an internet line, and the air conditioner. It is provided with a data storage device for accumulating the operation state data of the air conditioner, and the operation state data includes at least the expansion valve opening degree in the air conditioner, and the server includes the expansion valve opening degree. Using the expansion valve opening accumulated in the data storage device, the maximum expansion valve opening for each day for a predetermined period is calculated, and the calculated maximum expansion valve opening tends to increase and the maximum is said. It is characterized in that the refrigerant leakage is detected when the days when the opening degree of the expansion valve is equal to or larger than the first threshold value occur continuously.

Further, in order to solve the above problems, the refrigerant leakage detection system according to another aspect of the present invention is transmitted to the air conditioner, a server that can be connected to the air conditioner via the Internet line, and the server. It is provided with a data storage device for accumulating the operation state data of the air conditioner, and the operation state data includes at least the expansion valve opening degree in the air conditioner, and the server is the data. Using the expansion valve opening accumulated in the storage device, the maximum expansion valve opening for each day for a predetermined period is calculated, and the calculated maximum expansion valve opening tends to increase, and the maximum expansion It is characterized in that refrigerant leakage is detected when the maximum expansion valve opening during the valve opening increasing period is increased by a second threshold value or more as compared with that before the increase.

According to the above configuration, from the accumulated history of the expansion valve opening, the maximum expansion valve opening tends to increase, and the maximum expansion valve opening (or the rate of increase of the maximum expansion valve opening) is determined. It is determined that the threshold value is equal to or higher than a predetermined threshold value, and when both of these are positive determinations, the refrigerant leakage is detected. As a result, it is possible to detect the refrigerant leakage without using the operating state data of other air conditioners, and it is possible to accurately detect the refrigerant leakage. Further, since the judgment of the refrigerant leakage can be analyzed retroactively from the day when the air conditioner has a problem, a highly reliable detection result can be obtained.

Further, in the refrigerant leakage detection system, the maximum expansion valve opening calculated by the server extracts the maximum expansion valve opening extracted from the expansion valve openings stored a plurality of times in a day. When the maximum expansion valve opening is set, the corrected maximum expansion valve opening can be obtained by correcting the extracted maximum expansion valve opening using the correction parameter.

According to the above configuration, a more accurate detection result can be obtained by setting the maximum expansion valve opening used for detecting the refrigerant leakage to the corrected maximum expansion valve opening obtained by the correction using the correction parameter. ..

Further, in the refrigerant leakage detection system, the correction parameter may be configured to be at least one of the compressor rotation speed, the room temperature, the room humidity, and the outside air temperature.

Further, in the refrigerant leakage detection system, the air conditioner stores the expansion valve opening degree at regular time intervals multiple times a day, and the maximum expansion valve opening degree is calculated from the stored expansion valve opening degree for one day. Can be configured to be extracted and transmitted to the server.

According to the above configuration, the maximum expansion valve opening is extracted on the air conditioner side, and the extracted maximum expansion valve opening is transmitted to the server to reduce the amount of accumulated data of the data storage device and the communication load of the server. It can be suppressed.

The refrigerant leakage detection system of the present invention can detect refrigerant leakage without using operating state data of other air conditioners, and has an effect of accurately detecting refrigerant leakage in the air conditioner.

It is a figure which shows the schematic structure of the refrigerant leakage detection system which shows one Embodiment of this invention. It is a schematic block diagram of the air conditioner used in the refrigerant leakage detection system of FIG. It is a flowchart which shows the refrigerant leakage detection method in the refrigerant leakage detection system which concerns on Embodiment 1. FIG. It is a graph which shows an example of the daily change of the maximum expansion valve opening degree. It is a flowchart which shows the refrigerant leakage detection method in the refrigerant leakage detection system which concerns on Embodiment 2. (A) to (d) are diagrams showing an example of a correction table in the refrigerant leakage detection system according to the second embodiment.

[Embodiment 1]
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a diagram showing a schematic configuration of a refrigerant leakage detection system (hereinafter, referred to as this system) according to the first embodiment. FIG. 2 is a schematic configuration diagram of an air conditioner 10 applied to this system, and shows a refrigeration cycle applied in the air conditioner 10.

As shown in FIG. 1, this system is roughly configured to include an air conditioner 10, a server 20, and a data storage device 30. The air conditioner 10 is an air conditioner installed in a general house or the like, and can communicate with a server 20 at a remote location using an Internet line. For example, the air conditioner 10 communicates with the server 20 via an access point 50 installed in the same house, and the air conditioner 10 and the access point 50 communicate with each other using a wireless LAN. Then, communication can be performed between the access point 50 and the server 20 using an internet line. In FIG. 1, for convenience of explanation, the air conditioner 10 connected to the server 20 is shown as one, but in this system, a plurality of air conditioners 10 are connected to the server 20.

The server 20 periodically receives the operation state data from the connected air conditioner 10 and stores the operation state data in the data storage device 30. As a result, the past operating state data of the air conditioner 10 is accumulated in the data storage device 30. Further, the server 20 has a function of detecting the refrigerant leakage in the air conditioner 10 by using the past operation state data of the air conditioner 10 stored in the data storage device 30. Further, the server 20 has a function of transmitting the detection result of the refrigerant leak to the air conditioner 10 to the operation terminal 40 (smartphone, tablet, etc.) using the Internet line, the public switched telephone network (public network), or the like. There is.

As shown in FIG. 2, the air conditioner 10 is composed of an indoor unit 100 and an outdoor unit 110. An indoor heat exchanger 101 is provided on the indoor unit 100 side on the path of the refrigeration cycle (heat pump) in the air conditioner 10, and a compressor 111, an outdoor heat exchanger 112, and a four-way valve 113 are provided on the outdoor unit 110 side. And an expansion valve 114 is provided. Further, the indoor unit 100 is provided with an indoor fan 102 for sending out the air heat exchanged by the indoor heat exchanger 101 into the room, and the outdoor unit 110 is for sending air to the outdoor heat exchanger 112. The outdoor fan 115 is provided.

The four-way valve 113 switches the direction of refrigerant circulation according to the cooling / heating operation of the air conditioner 10 (FIG. 2 shows the state during the cooling operation). By switching the direction of refrigerant circulation with the four-way valve 113, the outdoor heat exchanger 112 functions as a condenser and the indoor heat exchanger 101 functions as an evaporator during cooling operation, and the indoor heat exchanger 101 condenses during heating operation. The vessel and the outdoor heat exchanger 112 function as an evaporator.

Further, the air conditioner 10 has a plurality of temperature sensors in order to detect the refrigerant temperature of each part in the refrigeration cycle and to detect the indoor temperature or the outside air temperature as needed. In the example of FIG. 2, the air conditioner 10 includes first to seventh temperature sensors 121 to 127. The first temperature sensor 121 detects the compressor discharge temperature. The second temperature sensor 122 detects the compressor suction temperature. The third temperature sensor 123 detects the refrigerant temperature in the outdoor heat exchanger 112. The fourth temperature sensor 124 detects the intake air temperature of the outdoor heat exchanger 112 as the outside air temperature. The fifth temperature sensor 125 detects the refrigerant temperature between the expansion valve 114 and the indoor heat exchanger 101 on the outdoor unit 110 side. The sixth temperature sensor 126 detects the intake air temperature of the indoor heat exchanger 101 as room temperature. The seventh temperature sensor 127 detects the refrigerant temperature in the indoor heat exchanger 101.

As described above, in this system, the operating state data of the air conditioner 10 is transmitted to the server 20 and stored in the data storage device 30. At this time, the operating state data stored in the data storage device 30 includes at least the expansion valve opening degree of the expansion valve 114. This is because in this system, the server 20 detects the refrigerant leakage in the air conditioner 10 based on the expansion valve opening degree accumulated in the data storage device 30.

That is, during the operation of the air conditioner 10, the opening degree of the expansion valve 114 is constantly controlled so that the normal operation of the air conditioner 10 is maintained, and the refrigerant circulation amount is adjusted. As the amount of refrigerant decreases, the expansion valve 114 is controlled so that the opening degree increases in order to increase the amount of refrigerant circulation. Specifically, the opening degree of the expansion valve 114 in the air conditioner 10 is controlled by targeting any one of the compressor discharge temperature, the compressor suction side superheat degree, and the compressor discharge side superheat degree. Since such a method for controlling the opening degree of the expansion valve is known, detailed description thereof will be omitted here. The control can be performed based on the temperature difference from the fifth temperature sensor 125, and the control can be performed based on the temperature difference between the second temperature sensor 122 and the third temperature sensor 123 during the heating operation.

When the air conditioner 10 transmits the expansion valve opening degree to the server 20 as operating state data, the unique number and the transmission time for identifying the air conditioner 10 are simultaneously transmitted. Further, the operation state data transmitted to the server 20 may include data other than the expansion valve opening degree. The operating state data of the air conditioner 10 includes, for example, cycle temperature, indoor temperature, indoor humidity, outside air temperature, current value, control information, error information, expansion valve opening degree, compressor rotation speed, fan rotation speed, etc. of each part. There is. In the first embodiment, the transmission of the operation state data from the air conditioner 10 to the server 20 is performed a plurality of times a day at regular time intervals. As a result, the data storage device 30 stores the operating state data from the installation of the air conditioner 10 to the present.

Subsequently, a method for detecting refrigerant leakage in the server 20 of this system will be described. When a refrigerant leaks in the air conditioner 10, the amount of the refrigerant decreases significantly in a short period of time. During that time, the maximum expansion valve opening degree of the air conditioner 10 tends to increase in order to increase the amount of refrigerant circulation. Therefore, in the refrigerant leakage detection method of this system, the maximum expansion valve opening is confirmed in chronological order at regular intervals from the accumulated operating state data, and the upward tendency of the maximum expansion valve opening is determined. Judge the refrigerant leakage. FIG. 3 is a flowchart showing a refrigerant leakage detection method of this system.

The timing at which the server 20 detects the refrigerant leakage from the air conditioner 10 is not particularly limited. Here, it is assumed that the refrigerant leakage is detected when the operator issues a refrigerant leakage detection instruction. Further, the operator in this case is, for example, a serviceman of the manufacturer, and when a repair request is received from the user of the air conditioner 10, it is conceivable to access the server 20 and issue a refrigerant leakage detection instruction. The refrigerant leakage detection instruction issued by the serviceman can be transmitted from the operation terminal 40 owned by the serviceman to the server 20.

When the refrigerant leak is detected for a specific air conditioner 10, the server 20 sets the maximum expansion valve opening every day for a predetermined period from the past operation state data accumulated in the data storage device 30. Is calculated. This calculation process corresponds to the steps S1 to S3 in the flowchart of FIG.

In this case, the predetermined period for acquiring the expansion valve opening degree from the data storage device 30 does not have to be a fixed length, and it is preferable that the serviceman can arbitrarily set it. This is because the user of the air conditioner 10 does not always issue a repair request immediately after a problem occurs in the air conditioner 10. When the user's repair request is delayed, by lengthening the predetermined period for acquiring the expansion valve opening degree, it is possible to reliably grasp the time when the refrigerant leak occurs and appropriately detect the refrigerant leak.

First, the server 20 acquires all the expansion valve openings for the past predetermined period (for example, one week) with respect to the air conditioner 10 from the data storage device 30 (S1).

When the server 20 acquires the past expansion valve opening degree from the data storage device 30, the expansion valve 20 is the expansion valve when the compressor is operating and the expansion valve 114 is normally controlled from the acquired expansion valve opening degree. The opening degree is extracted (S2). Such extraction of the expansion valve opening degree is performed in order to match the data conditions of the expansion valve opening degree used for detecting the refrigerant leakage. The air conditioner 10 may perform special control with the expansion valve opening degree as a fixed value, for example, during a start-up operation immediately after the power is turned on or during a defrosting operation. Since it is not appropriate to use the expansion valve opening degree during such special control for detecting refrigerant leakage, it is excluded in the step of S2. Further, the server 20 extracts the maximum daily expansion valve opening degree from the expansion valve opening degree extracted in S2 (S3). FIG. 4 shows an example of the maximum expansion valve opening degree extracted in S3, and is a graph showing the daily change of the maximum expansion valve opening degree. The maximum expansion valve opening degree extracted in S3 corresponds to the extraction maximum expansion valve opening degree described in the claims.

The server 20 determines whether or not the maximum expansion valve opening degree has continuously increased for a predetermined number of days (for example, 3 days) or more based on the maximum expansion valve opening degree extracted in S3 (S4). If YES in S4, the maximum expansion valve opening degree tends to increase, so that there is a possibility that refrigerant leakage has occurred, and the process shifts to S5. If NO in S4, it is determined that there is no refrigerant leakage because the maximum expansion valve opening degree does not show an upward tendency (S7). In the example of FIG. 4, since the maximum expansion valve opening degree has increased for 6 consecutive days from 8/3 to 8/8, it is determined as YES in S4.

Even if YES is determined in S4, it cannot be considered that there is refrigerant leakage unless the maximum expansion valve opening degree (or the rate of increase in the maximum expansion valve opening degree) is so large. For example, there is a possibility that the temperature itself tends to rise (or fall), and the maximum expansion valve opening tends to rise following such a change in temperature.

Therefore, when the server 20 determines YES in S4, the server 20 further determines the magnitude of the maximum expansion valve opening degree. In the example of FIG. 3, the server 20 determines whether or not the days when the maximum expansion valve opening degree is equal to or more than a predetermined threshold value (first threshold value: for example, 350 steps) are continuously generated (S5). This first threshold value corresponds to an expansion valve opening value that is large enough to be unlikely to occur in a normal ambient environment (outside air temperature, etc.) when there is no refrigerant leakage. If YES in S5, it is determined that there is refrigerant leakage because the state in which the maximum expansion valve opening degree is large is continuously generated (S6). If NO in S5, it is determined that there is no refrigerant leakage because the maximum expansion valve opening degree is not so large (S7). In the example of FIG. 4, since the maximum expansion valve opening degree is 350 steps or more continuously on 8/7 and 8/8, YES is determined in S5.

In S5 in the flowchart of FIG. 3, the magnitude of the maximum expansion valve opening degree is determined, but the present invention is not limited to this, and the magnitude of the increase rate of the maximum expansion valve opening degree is determined. You may. For example, the determination in S5 may be used to determine whether or not the maximum expansion valve opening has increased by a predetermined threshold value (second threshold value: for example, 200 steps) or more in the increase period of the maximum expansion valve opening degree as compared with that before the increase. Good. In the example of FIG. 4, since the maximum expansion valve opening has increased by 200 steps or more (238 = 370-132) during the increase period (8 / 2 to 8/8) of the maximum expansion valve opening, it is determined as YES in S5. Will be done.

As described above, the refrigerant leakage detection method of this system shows that the maximum expansion valve opening tends to increase and that the maximum expansion valve opening (or maximum expansion valve opening) is based on the accumulated history of the expansion valve opening. It is determined that the rate of increase in opening degree) is equal to or higher than a predetermined threshold value, and when both of these are positive determinations, refrigerant leakage is detected. As a result, it is possible to detect the refrigerant leakage without using the operating state data of other air conditioners, and it is possible to accurately detect the refrigerant leakage. Further, since the judgment of the refrigerant leakage can be analyzed retroactively from the day when the air conditioner 10 has a problem, a highly reliable detection result can be obtained.

The server 20 transmits the detection result of the refrigerant leakage to the air conditioner 10 (the detection result of S6 or S7) to the operation terminal 40 of the serviceman who has issued the refrigerant leakage detection instruction. As a result, the serviceman can confirm the presence or absence of refrigerant leakage before going to repair the air conditioner 10.

[Embodiment 2]
In the refrigerant leakage detection method according to the first embodiment, the maximum daily expansion valve opening is extracted from the accumulated past expansion valve opening, and the refrigerant leakage is detected based on the extracted maximum expansion valve opening. Is going. However, the expansion valve opening varies depending on parameters such as compressor rotation speed, room temperature, room humidity, and outside air temperature. Therefore, if these parameters are different in the extracted maximum expansion valve opening, refrigerant leakage will occur. There may be some error in the detection result.

In the refrigerant leakage detection method according to the second embodiment, the maximum expansion valve opening degree used for detecting the refrigerant leakage is corrected by at least one of the compressor rotation speed, the room temperature, the room humidity, and the outside air temperature. As a result, a more accurate detection result can be obtained. FIG. 5 is a flowchart showing a refrigerant leakage detection method of the present system according to the second embodiment. The flowchart shown in FIG. 5 is different from the flowchart shown in FIG. 3 only in that the step S31 is added between S3 and S4.

In the step of S31, the maximum expansion valve opening degree extracted in S3 is corrected by the corresponding correction parameter. The correction parameter here is at least one of the compressor rotation speed, the room temperature, the room humidity, and the outside air temperature. The correction parameter used for the correction in S31 is included in the operation state data transmitted from the air conditioner 10 to the server 20 together with the expansion valve opening degree, and is associated with the expansion valve opening degree in the data storage device 30. Is remembered.

A specific example of the method for correcting the maximum expansion valve opening degree in the step of S31 will be described with reference to FIG. Specifically, for the maximum expansion valve opening degree, a correction value is read from the correction table shown in FIGS. 6A to 6D, and the read correction value is added to the maximum expansion valve opening degree. The maximum expansion valve opening degree corrected in S31 corresponds to the corrected maximum expansion valve opening degree described in the claims.

FIG. 6A shows a correction table when the compressor rotation speed is used as a correction parameter. The case where correction is performed using the compressor rotation speed as a correction parameter will be described below using the graph of FIG. 4 as an example. The correction using the compressor rotation speed as the correction parameter can be applied regardless of whether the air conditioner 10 is performing the cooling operation or the heating operation.

For example, assuming that the compressor rotation speed stored corresponding to the maximum expansion valve opening degree "358" of 8/7 is 2000 rpm, the correction value at this time is "from the correction table of FIG. 6 (a)". It is 50 ". Then, by adding the correction value "50" to the maximum expansion valve opening degree "358" of 8/7, the maximum expansion valve opening degree after correction becomes "408". Further, assuming that the compressor rotation speed stored corresponding to the maximum expansion valve opening degree "370" of 8/8 is 3000 rpm, the correction value at this time is "25". Then, by adding the correction value "25" to the maximum expansion valve opening degree "370" of 8/8, the maximum expansion valve opening degree after correction becomes "395". The maximum expansion valve opening degree between 8/2 and 8/6 can be similarly corrected.

FIG. 6B shows a correction table when the room temperature is used as the correction parameter. The case of performing correction using the room temperature as a correction parameter will be described below using the graph of FIG. 4 as an example. The correction using the room temperature as the correction parameter can be applied when the air conditioner 10 is in the cooling operation.

For example, assuming that the room temperature stored corresponding to the maximum expansion valve opening degree "358" of 8/7 is 25 ° C., the correction value at this time is "0" from the correction table of FIG. 6B. ". Therefore, the maximum expansion valve opening degree "358" of 8/7 also has the corrected maximum expansion valve opening degree "358". Further, assuming that the room temperature stored corresponding to the maximum expansion valve opening degree "370" of 8/8 is 30 ° C., the correction value at this time is "-10". Then, by adding the correction value "-10" to the maximum expansion valve opening degree "370" of 8/8, the maximum expansion valve opening degree after correction becomes "360". The maximum expansion valve opening degree between 8/2 and 8/6 can be similarly corrected.

FIG. 6C shows a correction table when indoor humidity is used as a correction parameter (applicable when cooling operation is performed). FIG. 6D shows a correction table when the outside air temperature is used as the correction parameter (applicable when the heating operation is performed). When these correction parameters are used, the correction can be performed in the same manner.

When the above-mentioned correction is performed in S31 of FIG. 5, the processes of S4 to S7 are performed using the corrected maximum expansion valve opening degree. The processes of S4 to S7 are the same as the processes described in the first embodiment.

As described above, in the refrigerant leakage detection method according to the second embodiment, the maximum expansion valve opening degree is corrected by using the correction parameter, and the refrigerant leakage is detected based on the corrected maximum expansion valve opening degree. There is. This makes it possible to detect refrigerant leakage with higher accuracy.

[Embodiment 3]
In the refrigerant leakage detection method according to the first and second embodiments, the operation state data is transmitted from the air conditioner 10 to the server 20 a plurality of times a day at regular time intervals. Then, the server 20 extracts the maximum expansion valve opening degree for each day from the accumulated past expansion valve opening degree, and detects the refrigerant leakage based on the extracted maximum expansion valve opening degree. On the other hand, in the present system according to the third embodiment, the above-mentioned extraction process is performed not by the server 20 but by the air conditioner 10.

Specifically, the air conditioner 10 stores the operation state data at regular time intervals a plurality of times a day. The stored operation state data for one day is stored in the memory included in the air conditioner 10.

At a predetermined time, the air conditioner 10 performs an extraction process on the stored operation state data for one day. Only the extracted operation status data is transmitted to the server 20. Here, the extraction process performed by the air conditioner 10 is a process of extracting the maximum expansion valve opening degree from the operating state data for one day, and is the process of S2 and S3 of FIG. 3 or FIG. Equivalent to.

As described above, in the present system according to the third embodiment, the process of extracting the maximum expansion valve opening degree is performed on the air conditioner 10 side, and the extracted maximum expansion valve opening degree is transmitted to the server 20. The amount of data stored in the data storage device 30 and the communication load of the server 20 can be suppressed. As a result, a more reliable judgment result can be obtained.

The embodiments disclosed this time are examples in all respects and do not serve as a basis for limited interpretation. Therefore, the technical scope of the present invention is not construed solely by the above-described embodiments, but is defined based on the description of the claims. It also includes all changes within the meaning and scope of the claims.

10 Air conditioner 20 Server 30 Data storage device 40 Operation terminal 50 Access point 100 Indoor unit 101 Indoor heat exchanger 102 Indoor fan 110 Outdoor unit 111 Compressor 112 Outdoor heat exchanger 113 Four-way valve 114 Expansion valve 115 Outdoor fan 121-127 1st to 7th temperature sensors

Claims (5)

With an air conditioner
A server that can connect to an air conditioner via an internet line,
It is equipped with a data storage device that stores the operating state data of the air conditioner transmitted from the air conditioner to the server.
The operating state data includes at least the expansion valve opening degree in the air conditioner.
The server
Using the expansion valve opening stored in the data storage device, the maximum daily expansion valve opening for a predetermined period is calculated.
It is characterized in that refrigerant leakage is detected when the calculated maximum expansion valve opening degree tends to increase and the days when the maximum expansion valve opening degree is equal to or higher than the first threshold value occur continuously. Refrigerant leak detection system. With an air conditioner
A server that can connect to an air conditioner via an internet line,
It is equipped with a data storage device that stores the operating state data of the air conditioner transmitted to the server.
The operating state data includes at least the expansion valve opening degree in the air conditioner.
The server
Using the expansion valve opening stored in the data storage device, the maximum daily expansion valve opening for a predetermined period is calculated.
Refrigerant leakage when the calculated maximum expansion valve opening tends to increase and the maximum expansion valve opening during the increase period of the maximum expansion valve opening increases by a second threshold value or more compared to before the increase. Refrigerant leak detection system characterized by detecting. The refrigerant leakage detection system according to claim 1 or 2.
The maximum expansion valve opening calculated by the server is obtained when the maximum expansion valve opening extracted from the expansion valve openings stored a plurality of times in a day is taken as the extraction maximum expansion valve opening. A refrigerant leakage detection system characterized in that it is a corrected maximum expansion valve opening degree obtained by correcting the extraction maximum expansion valve opening degree using a correction parameter. The refrigerant leakage detection system according to claim 3.
The refrigerant leakage detection system is characterized in that the correction parameter is at least one of the compressor rotation speed, the room temperature, the room humidity, and the outside air temperature. The refrigerant leakage detection system according to any one of claims 1 to 3.
The air conditioner stores the expansion valve opening a plurality of times a day at regular time intervals, extracts the maximum expansion valve opening from the stored expansion valve opening for one day, and transmits the maximum expansion valve opening to the server. A refrigerant leak detection system characterized by this.

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