Refrigerant diagnosis method and apparatus, and multi-split air conditioner and storage medium

Abstract

Disclosed in the present application are a refrigerant diagnosis method and apparatus, and a multi-split air conditioner and a storage medium. In the present invention, the method comprises: when a multi-split air conditioner meets a refrigerant diagnosis condition, acquiring an outdoor ambient temperature of an outdoor unit; determining an operation mode of the multi-split air conditioner on the basis of the outdoor ambient temperature, and calculating a refrigerant determination parameter and a temperature difference parameter on the basis of the operation mode; and determining a refrigerant amount on the basis of the refrigerant determination parameter and the temperature difference parameter.

Description

Refrigerant diagnosis method, device, multi-split air conditioner and storage medium

[0001] This application claims priority to Chinese patent application No. 202310951120.9 filed on July 31, 2023, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the technical field of air conditioners, and in particular to a refrigerant diagnosis method, device, multi-split air conditioner and storage medium. Background Art

[0003] Multi-split systems feature numerous indoor units, resulting in complex and long piping connections and requiring a large refrigerant charge. This complexity and the large number of indoor units can lead to miscalculation, resulting in either excessive or insufficient refrigerant in the system. Furthermore, multi-split systems typically have numerous welds and installation quality varies widely. Failure to maintain pressure long enough before refrigerant charging can lead to micro-leakage during system startup or refrigerant leakage through the high-pressure system after a period of operation, resulting in refrigerant shortages. Excessive refrigerant levels can, in severe cases, cause liquid backflow, leading to liquid compression, or excessive system pressure, triggering a high-pressure shutdown. Low refrigerant levels can lead to refrigerant starvation in indoor units, resulting in insufficient capacity and inability to meet user cooling and heating needs. Furthermore, excessive overheating can trigger high-discharge temperature or low-pressure shutdowns. Therefore, determining the appropriate refrigerant level in the system is crucial for practical engineering applications. In related technologies, the system refrigerant quantity is mainly judged by the compressor exhaust, the compressor exhaust superheat, the system high and low pressures, the compressor return air superheat, etc., but misjudgment sometimes occurs in complex usage environments.

[0004] The above content is only used to assist in understanding the technical solution of this application and does not constitute an admission that the above content is prior art. Technical issues

[0005] The main purpose of this application is to provide a refrigerant diagnosis method, device, multi-split air conditioner and storage medium, aiming to solve the technical problems of inaccurate refrigerant quantity diagnosis of multi-split air conditioners in the prior art and easy misjudgment in complex environments. Technical Solutions

[0006] To achieve the above objectives, the present application provides a refrigerant diagnostic method, which is applied to a multi-split air conditioner, wherein the multi-split air conditioner includes an outdoor unit and multiple indoor units. The refrigerant diagnostic method for the air conditioner includes:

[0007] When the multi-split air conditioner meets the refrigerant diagnosis condition, obtaining the outdoor ambient temperature of the outdoor unit;

[0008] Determining an operating mode of the multi-split air conditioner according to the outdoor ambient temperature, and calculating a refrigerant determination parameter and a temperature difference parameter according to the operating mode; and

[0009] The amount of refrigerant is determined based on the refrigerant determination parameter and the temperature difference parameter.

[0010] In one embodiment, when the multi-split air conditioner meets the refrigerant diagnosis condition, obtaining the outdoor ambient temperature of the outdoor unit includes:

[0011] When the multi-split air conditioner enters the refrigerant diagnosis function, controlling the outdoor fan of the outdoor unit to run according to the target wind speed for an initial stable time;

[0012] determining a target indoor unit from among the indoor units, the target indoor unit being the indoor unit participating in the refrigerant diagnosis;

[0013] Calculating the sum of the indoor unit rated capacity of each target indoor unit and the outdoor unit rated capacity of the outdoor unit; and

[0014] When the ratio of the sum of the rated capacities of the indoor units to the rated capacities of the outdoor units is a preset ratio, it is determined that the multi-split air conditioner meets a refrigerant diagnosis condition, and the outdoor ambient temperature of the outdoor unit is obtained.

[0015] In one embodiment, determining the operating mode of the multi-split air conditioner according to the outdoor ambient temperature, and calculating the refrigerant determination parameter and the temperature difference parameter according to the operating mode include:

[0016] When the outdoor ambient temperature meets a preset temperature range, determining that the operation mode of the multi-split air conditioner is a cooling mode;

[0017] Obtaining the expansion valve opening, high pressure saturation temperature, and condenser outlet temperature of each indoor unit that is turned on within a first preset time period;

[0018] Determining a refrigerant determination parameter according to the expansion valve opening; and

[0019] A temperature difference parameter is calculated based on the high-pressure saturation temperature and the condenser outlet temperature, where the temperature difference parameter is the difference between an average value of the high-pressure saturation temperature and an average value of the condenser outlet temperature.

[0020] In one embodiment, after determining that the operating mode of the multi-split air conditioner is the cooling mode when the outdoor ambient temperature meets a preset temperature range, the method further includes:

[0021] Obtaining the expansion valve opening of the powered-on indoor unit in each indoor unit, the condenser outlet temperature of the outdoor unit, and the outdoor unit return air temperature;

[0022] Determining a refrigerant determination parameter according to the expansion valve opening; and

[0023] A temperature difference parameter is calculated based on the outdoor unit return air temperature and the condenser outlet temperature, where the temperature difference parameter is the difference between an average value of the outdoor unit return air temperature and an average value of the condenser outlet temperature.

[0024] In one embodiment, determining the refrigerant judgment parameter according to the expansion valve opening includes:

[0025] Calculating an average opening degree according to the expansion valve opening degree;

[0026] Reading the minimum cooling opening of the expansion valve of each powered-on indoor unit, and calculating the average minimum opening of the minimum cooling opening; and

[0027] A refrigerant judgment parameter is calculated according to the average opening value and the average minimum opening value, and the refrigerant judgment parameter is a ratio of the average opening value to the average minimum opening value.

[0028] In one embodiment, determining the operating mode of the multi-split air conditioner according to the outdoor ambient temperature, and calculating the refrigerant determination parameter and the temperature difference parameter according to the operating mode include:

[0029] When the outdoor ambient temperature does not meet the preset temperature range, determining that the operation mode of the multi-split air conditioner is a heating mode;

[0030] Obtaining the heat exchanger inlet temperature, high pressure saturation temperature and main expansion valve opening of each indoor unit in the second preset time period;

[0031] Calculating an average value of the inlet temperature of each heat exchanger, an average value of the main expansion valve opening of the main expansion valve, and an average value of the saturation temperature of the high-pressure saturation temperature;

[0032] Determining a refrigerant judgment parameter based on the average inlet temperature; and

[0033] A temperature difference parameter is determined according to the average opening degree of the main expansion valve and the average saturation temperature.

[0034] In one embodiment, the determining the refrigerant amount based on the refrigerant determination parameter and the temperature difference parameter includes:

[0035] Selecting an opening comparison threshold range according to the refrigerant judgment parameter;

[0036] Selecting a temperature comparison threshold range according to the temperature difference parameter;

[0037] Comparing the refrigerant judgment parameter with the opening comparison threshold range to obtain an opening comparison result, and comparing the temperature difference parameter with the temperature comparison threshold range to obtain a temperature comparison result; and

[0038] The refrigerant amount of the multi-split air conditioner is determined based on the opening comparison result and the temperature comparison result.

[0039] In addition, to achieve the above-mentioned purpose, the present application also proposes a refrigerant diagnostic device, which includes:

[0040] a temperature acquisition module, configured to acquire the outdoor ambient temperature of the outdoor unit when the multi-split air conditioner meets the refrigerant diagnosis condition;

[0041] a parameter calculation module, configured to determine an operating mode of the multi-split air conditioner according to the outdoor ambient temperature, and calculate a refrigerant determination parameter and a temperature difference parameter according to the operating mode; and

[0042] The refrigerant diagnosis module is used to determine the amount of refrigerant based on the refrigerant judgment parameter and the temperature difference parameter.

[0043] In addition, to achieve the above-mentioned purpose, the present application also proposes a multi-split air conditioner, which includes: a memory, a processor, and a refrigerant diagnostic program stored on the memory and running on the processor, and the refrigerant diagnostic program is configured to implement the refrigerant diagnostic method described above.

[0044] In addition, to achieve the above-mentioned purpose, the present application also proposes a storage medium, on which a refrigerant diagnostic program is stored. When the refrigerant diagnostic program is executed by a processor, the refrigerant diagnostic method as described above is implemented. Beneficial effects

[0045] The present application obtains the outdoor ambient temperature of the outdoor unit when the multi-split air conditioner meets the refrigerant diagnosis conditions; determines the operating mode of the multi-split air conditioner based on the outdoor ambient temperature, calculates the refrigerant judgment parameter and the temperature difference parameter based on the operating mode; and determines the refrigerant quantity based on the refrigerant judgment parameter and the temperature difference parameter. In this way, when the multi-split air conditioner meets the refrigerant diagnosis conditions, the refrigerant quantity is determined based on the temperature parameters of the outdoor and indoor units and the refrigerant judgment parameter, making the determination of the refrigerant quantity more accurate. When the refrigerant quantity is insufficient, it is convenient for installation and after-sales personnel to handle it in a timely manner, avoiding the impact of too much or too little refrigerant on the reliability and comfort of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] FIG1 is a schematic structural diagram of a multi-split air conditioner in a hardware operating environment according to an embodiment of the present application;

[0047] FIG2 is a flow chart of a first embodiment of the refrigerant diagnostic method of the present application;

[0048] FIG3 is a flow chart of a second embodiment of the refrigerant diagnostic method of the present application;

[0049] FIG4 is a flow chart of a third embodiment of the refrigerant diagnostic method of the present application;

[0050] FIG5 is a schematic diagram of a complete implementation process of an embodiment of the refrigerant diagnosis method of the present application;

[0051] FIG6 is a structural block diagram of the first embodiment of the refrigerant diagnostic device of the present application.

[0052] The realization of the objectives, functional features and advantages of this application will be further explained in conjunction with embodiments and with reference to the accompanying drawings. Modes for Carrying Out the Invention

[0053] It should be understood that the specific embodiments described herein are only used to explain the present application and are not intended to limit the present application.

[0054] Refer to Figure 1, which is a schematic diagram of the structure of a multi-split air conditioner in a hardware operating environment according to an embodiment of the present application.

[0055] As shown in Figure 1, the multi-split air conditioner may include: a processor 1001, such as a central processing unit (CPU), a communication bus 1002, a user interface 1003, a network interface 1004, and memory 1005. The communication bus 1002 is used to enable communication between these components. The user interface 1003 may include a display and an input unit, such as a keyboard. The user interface 1003 may also include a standard wired interface or a wireless interface. The network interface 1004 may include a standard wired interface or a wireless interface (such as a Wireless Fidelity (Wi-Fi) interface). The memory 1005 may be a high-speed random access memory (RAM) or a stable non-volatile memory (NVM), such as a disk drive. The memory 1005 may also be a storage device independent of the processor 1001.

[0056] Those skilled in the art will understand that the structure shown in FIG1 does not constitute a limitation on the multi-split air conditioner, and may include more or fewer components than shown in the figure, or a combination of certain components, or a different arrangement of components.

[0057] As shown in FIG. 1 , the memory 1005 as a storage medium may include an operating system, a network communication module, a user interface module, and a refrigerant diagnostic program.

[0058] In the multi-split air conditioner shown in Figure 1, the network interface 1004 is mainly used for data communication with the network server; the user interface 1003 is mainly used for data interaction with the user; the processor 1001 and the memory 1005 in the multi-split air conditioner of the present application can be set in the multi-split air conditioner, and the multi-split air conditioner calls the refrigerant diagnostic program stored in the memory 1005 through the processor 1001, and executes the refrigerant diagnostic method provided by the present application.

[0059] The present application provides a refrigerant diagnosis method. Referring to FIG. 2 , FIG. 2 is a flow chart of a first embodiment of a refrigerant diagnosis method provided by the present application.

[0060] In one embodiment, the refrigerant diagnosis method includes the following steps:

[0061] Step S10: When the multi-split air conditioner meets the refrigerant diagnosis condition, the outdoor ambient temperature of the outdoor unit is obtained.

[0062] In one embodiment, the execution subject may be a multi-split air conditioner, which has functions such as data processing, data communication, and program execution. The multi-split air conditioner may be any model of a multi-split air conditioner including multiple indoor units. Of course, other devices with similar functions may also be used, and these implementation conditions do not impose any restrictions. For ease of explanation, this embodiment uses a multi-split air conditioner as an example.

[0063] It's important to note that multi-split systems, with their numerous indoor units and complex, long piping connections, require a large amount of refrigerant to be filled. This complexity and the large number of indoor units can lead to miscalculation, resulting in either too much or too little refrigerant in the system. Furthermore, multi-split systems typically have numerous welds, and installation quality varies widely. Failure to maintain pressure long enough before refrigerant filling can lead to micro-leakage during system startup or refrigerant leakage through the high-pressure system after a period of operation, resulting in refrigerant shortages. Excessive refrigerant levels can, in severe cases, cause liquid backflow, leading to liquid compression, or excessive system pressure, triggering a high-pressure shutdown. Low refrigerant levels can lead to a refrigerant shortage in the indoor units, resulting in insufficient capacity and an inability to meet user cooling and heating needs. Furthermore, excessive overheating can trigger high-discharge temperature or low-pressure shutdowns. Therefore, determining the appropriate amount of refrigerant in the system is crucial for practical engineering applications. In related technologies, system refrigerant quantity is primarily determined based on compressor exhaust, compressor exhaust superheat, system high and low pressures, and compressor return air superheat. However, this method can sometimes lead to misjudgments in complex operating environments. This solution, however, determines refrigerant quantity based on outdoor and indoor unit temperature parameters and refrigerant determination parameters, provided the multi-split air conditioner meets refrigerant diagnosis requirements. This makes refrigerant quantity determination more accurate, facilitates timely handling by installers and after-sales personnel when refrigerant quantity is insufficient, and prevents the impact of excessive or insufficient refrigerant on system reliability and comfort.

[0064] It should be understood that before the program starts, it is necessary to first determine whether the multi-split air conditioner meets the starting conditions of the refrigerant diagnosis function. Specifically, to determine whether the refrigerant diagnosis conditions are met, the multi-split air conditioner must first be initialized and run, and then it is determined whether the rated capacity of the indoor units participating in the diagnosis meets the comprehensive conditions.

[0065] Furthermore, in order to determine whether the multi-split air conditioner meets the refrigerant diagnosis conditions, in step S10, it is first determined that the multi-split air conditioner enters the refrigerant diagnosis function, and then the outdoor fan of the outdoor unit is controlled to run according to the target wind speed for an initial stable time. Specifically, the outdoor fan is controlled to run at a high wind speed for a period of time TIME1, so that the outdoor return air temperature sensor T4 can detect accurately and the outdoor return air temperature is the same as the outdoor ambient temperature.

[0066] In one embodiment, after the multi-split air conditioner completes initialization operation, the indoor units that need to undergo refrigerant quantity diagnosis are determined from among the indoor units as target indoor units. The target indoor units are pre-set or selected by the user and can be any number of indoor units. This embodiment does not impose any limitation on this.

[0067] It should be noted that, after the target indoor units are determined, the rated capacity of each target indoor unit is calculated, and the stable capacity of the outdoor units in the multi-split air conditioner is obtained.

[0068] It should be understood that the total rated capacity of the target indoor units is required to be R% of the rated capacity of the outdoor units (R is generally 80-120, for example, 100). At this time, it is determined that the multi-split air conditioner meets the refrigerant diagnosis conditions, so the step of obtaining the outdoor ambient temperature of the outdoor unit is entered.

[0069] In this way, it is possible to determine whether the multi-split air conditioner meets the diagnostic prerequisites before performing refrigerant quantity diagnosis, thereby preventing misjudgment.

[0070] Step S20: determining the operating mode of the multi-split air conditioner according to the outdoor ambient temperature, and calculating the refrigerant determination parameter and the temperature difference parameter according to the operating mode.

[0071] In one embodiment, determining the operating mode of the multi-split air conditioner based on the outdoor ambient temperature means determining whether the multi-split air conditioner is in heating mode or cooling mode based on the specific value of the outdoor ambient temperature, and then calculating different refrigerant judgment parameters and temperature difference parameters according to different operating modes.

[0072] Step S30: determining the amount of refrigerant based on the refrigerant determination parameter and the temperature difference parameter.

[0073] It should be noted that after the refrigerant judgment parameter and the temperature difference parameter are determined, the refrigerant judgment parameter is compared with the opening comparison threshold range, and the temperature difference parameter is compared with the temperature comparison threshold range, and the refrigerant amount is judged and diagnosed based on the two comparison results.

[0074] Furthermore, in order to accurately determine the amount of refrigerant, in step S30, the opening comparison threshold range is first selected according to the refrigerant judgment parameter. Specifically, different opening comparison threshold ranges and temperature comparison threshold ranges are determined according to the operating mode of the multi-split air conditioner.

[0075] It should be understood that, in the cooling mode, Rp is first determined as the refrigerant judgment parameter, and Rp0 and Rp1 are pre-set reference thresholds, that is, the opening comparison threshold range.

[0076] Therefore, in cooling mode, the steps of comparing the cooling capacity judgment parameter with the opening degree comparison threshold range include: Rp is greater than Rp1. If Rp>=Rp0, a serious refrigerant shortage is indicated, and the process ends; otherwise, proceed to the next step. If Rp>=Rp1, a refrigerant shortage is indicated, and the process ends; otherwise, proceed to the next step.

[0077] In one embodiment, in the refrigeration mode, the temperature comparison threshold range is determined to be less than the threshold range of A, and A can be any preset temperature threshold. Therefore, the determination method of the temperature comparison result in the refrigeration mode is as follows: If TCavg - T3avg < A, it is prompted that the refrigerant amount is in the normal range, and the process ends; otherwise, it is prompted that there is too much refrigerant, and the process ends. Where TCavg is the average value of the high-pressure saturation temperature, and T3avg is the average value of the refrigerant outlet temperature of the outdoor unit.

[0078] It should be noted that in the heating mode, first, Poavg is determined as the refrigerant judgment parameter. At this time, the opening comparison threshold range consists of three thresholds, P0, P1, and P2, where P0, P1, and P2 are any increasing values in sequence. Therefore, the judgment steps of the opening comparison result are as follows: If Poavg <= P0, it is prompted that there is seriously too much refrigerant, and the process ends; otherwise, proceed to the next step. If Poavg <= P1, it is prompted that there is too much refrigerant, and the process ends; otherwise, proceed to the next step. If Poavg <= P2, it is prompted that the refrigerant amount is in the normal range, and the process ends; otherwise, proceed to the next step.

[0079] It should be understood that in the heating mode, the temperature comparison threshold range is determined to be less than the value range of B, where B can be any preset temperature threshold. Therefore, the determination method of the temperature comparison result in the heating mode is as follows: If TCavg - TAavg < B, it is prompted that there is seriously too little refrigerant, and the process ends; otherwise, it is prompted that there is too little refrigerant, and the process ends. Where TCavg is the average value of the high-pressure saturation temperature, and TAavg is the average value of the heat exchanger inlet temperature.

[0080] In this way, the parameters participating in the refrigerant diagnosis are realized, and can be processed in intervals according to the corresponding outdoor return air temperature T4 (for each T4 interval, different parameter values can be taken), so that the refrigerant amount can be accurately determined.

[0081] This application realizes the determination of the refrigerant amount based on the temperature parameters of the outdoor unit and the indoor unit and the refrigerant judgment parameter when the multi-connected air conditioner meets the refrigerant diagnosis conditions, making the judgment of the refrigerant amount more accurate. When the refrigerant amount is insufficient, it is convenient for the installation and after-sales personnel to handle it in time, avoiding the impact of too much or too little refrigerant on the reliability and comfort of the system.

[0082] Referring to FIG. 3, FIG. 3 is a schematic flow chart of a second embodiment of a refrigerant diagnosis method provided by this application.

[0083] Based on the above first embodiment, in one embodiment, the refrigerant diagnosis method in the step S20 includes:

[0084] Step S201: When the outdoor ambient temperature meets the preset temperature range, determine that the operating mode of the multi-connected air conditioner is the refrigeration mode.

[0085] It should be noted that the outdoor ambient temperature is first compared with a preset temperature range to determine whether the multi-split air conditioner is operating in cooling mode or heating mode. Specifically, if T4>=TCOOL, the operating mode is determined to be cooling mode. TCOOL is a preset temperature threshold value and can be any value. This embodiment does not limit this.

[0086] Furthermore, in order to realize the judgment of the refrigerant amount in a low-cost multi-split air conditioner that is not equipped with a high-pressure pressure sensor, after step S201, within a first preset time period, the expansion valve openings P1, P2...PN (N is the total number of powered-on indoor units), the outdoor unit return air temperature T4, and the outdoor unit condenser outlet temperature T3 of all powered-on indoor units are obtained.

[0087] It should be understood that the refrigerant judgment parameter is then calculated as the above-mentioned indoor unit opening degrees P1, P2...PN, taking the average value Pavg, and calculating the ratio Rp of Pavg and Pmin-cool. Among them, the minimum cooling opening degree of the expansion valve of the powered indoor unit is read and its average value Pmin-cool is calculated.

[0088] In one embodiment, the temperature difference parameter is T3avg-T4avg, wherein the average values ​​of T4 and T3 are T4avg and T3avg, respectively.

[0089] In this way, it is possible to accurately determine the refrigerant amount through parameter calculation in a low-cost multi-split air conditioner that is not equipped with a high-pressure pressure sensor.

[0090] Step S202: obtaining the expansion valve opening degree, high pressure saturation temperature and condenser outlet temperature of each indoor unit that is turned on within a first preset time period.

[0091] It should be understood that when it is determined to be operating in cooling mode, the multi-split air conditioner is first controlled to start cooling operation and timing, and the parameters of the operation from TIME2 minutes to TIME3 minutes are recorded and processed, where the first preset time period is from TIME2 minutes to TIME3 minutes.

[0092] In one embodiment, the acquired parameters include: the expansion valve openings P1, P2...PN of all powered-on indoor units (N is the total number of powered-on indoor units), the outdoor unit return air temperature T4, the high-pressure saturation temperature TC (which can be calculated from the high-pressure pressure sensor data), and the outdoor unit condenser outlet temperature T3.

[0093] Step S203: determining a refrigerant determination parameter according to the expansion valve opening.

[0094] It should be noted that the refrigerant judgment parameter is calculated based on the opening value of the expansion valve.

[0095] Further, in order to accurately calculate the refrigerant judgment parameter, first calculate the average value of the expansion valve opening degrees of all the turned-on indoor units during startup, denoted as Pavg.

[0096] It should be understood that then read the minimum opening degree of the expansion valve of each turned-on indoor unit of the current multi-connected air conditioner in the refrigeration state, so as to calculate the average value of the minimum refrigeration opening degrees of all the turned-on indoor units, denoted as Pmin-cool.

[0097] In one embodiment, finally calculate the ratio Rp of Pavg and Pmin-cool, and use Rp as the refrigerant judgment parameter.

[0098] Step S204: Calculate the temperature difference parameter based on the high-pressure saturation temperature and the condenser outlet temperature, where the temperature difference parameter is the difference between the average value of the high-pressure saturation temperature and the average value of the condenser outlet temperature.

[0099] It should be noted that the temperature difference parameter is determined as TCavg - T3avg, where the average values of TC and T3 are taken as TCavg and T3avg respectively.

[0100] In this application, during refrigeration operation, the ratio Rp of the average value Pavg of the opening degrees of the operating indoor units and Pmin-cool is used, and the average values TCavg and T3avg of the outdoor unit parameters TC and T3 are combined to judge the amount of refrigerant.

[0101] Referring to FIG. 4, FIG. 4 is a schematic flowchart of a third embodiment of a refrigerant diagnosis method provided by this application.

[0102] Based on the above first embodiment, in one embodiment, the refrigerant diagnosis method in the step S20 includes:

[0103] Step S21: When the outdoor ambient temperature does not meet the preset temperature range, determine the operating mode of the multi-connected air conditioner as the heating mode.

[0104] It should be noted that when the outdoor ambient temperature T4 < TCOOL, it is determined that the outdoor ambient temperature does not meet the preset temperature range, so the operating mode of the multi-connected air conditioner is determined as the heating mode.

[0105] Step S22: Obtain the heat exchanger inlet temperature, high-pressure saturation temperature of each turned-on indoor unit in the second preset time period, and the main expansion valve opening degree of the outdoor unit.

[0106] It should be understood that heating operation begins and timing is recorded and processed during the period from TIME4 to TIME5. Specifically, the heat exchanger inlet temperatures TA1, TA2, ...TAN (N is the total number of active indoor units), the outdoor unit return air temperature T4, the outdoor unit main expansion valve opening Po, and the high-pressure saturation temperature TC (which can be calculated from the high-pressure pressure sensor data) of all powered-on indoor units. The second preset time period refers to the period from TIME4 to TIME5.

[0107] Step S23: Calculate the average inlet temperature of each heat exchanger inlet temperature, the average main expansion valve opening degree of the main expansion valve opening, and the average saturation temperature of the high-pressure saturation temperature.

[0108] In one embodiment, the inlet temperatures TA1, TA2, ..., TAN of the indoor heat exchangers are calculated and the average value TAavg is obtained. The average values ​​Poavg and TCavg of the outdoor heat exchangers Po and TC are obtained.

[0109] Step S24: determining a refrigerant judgment parameter according to the average inlet temperature.

[0110] It should be noted that the refrigerant judgment parameter at this time is Poavg, which is the average value of the main expansion valve opening of the outdoor unit of the multi-split air conditioner.

[0111] Step S25: determining a temperature difference parameter according to the average value of the main expansion valve opening and the average value of the saturation temperature.

[0112] It should be understood that the temperature difference parameter in the heating mode is TCavg-TAavg.

[0113] 5 is a complete implementation flow of an embodiment of the present application, in which the refrigerant quantity of a multi-split air conditioner can be determined in different operating modes.

[0114] In one embodiment, during heating operation, the amount of refrigerant is determined by using the average value of the inlet temperature of the indoor heat exchanger TAavg and the average values ​​of the main expansion valve opening Po and the high-pressure saturation temperature TC of the outdoor parameters Poavg and TCavg.

[0115] In addition, the present application also proposes a storage medium, on which a refrigerant diagnostic program is stored. When the refrigerant diagnostic program is executed by a processor, the steps of the refrigerant diagnostic method described above are implemented.

[0116] Since the storage medium adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought by the technical solutions of the above embodiments, which will not be described one by one here.

[0117] Refer to FIG. 6 , which is a structural block diagram of a first embodiment of a refrigerant diagnostic device provided by the present application.

[0118] As shown in FIG6 , the refrigerant diagnostic device proposed in this application includes:

[0119] The temperature acquisition module 10 is used to obtain the outdoor ambient temperature of the outdoor unit when the multi-split air conditioner meets the refrigerant diagnosis condition.

[0120] In one embodiment, the execution subject may be a multi-split air conditioner, which has functions such as data processing, data communication, and program execution. The multi-split air conditioner may be any model of a multi-split air conditioner including multiple indoor units. Of course, other devices with similar functions may also be used, and these implementation conditions do not impose any restrictions. For ease of explanation, this embodiment uses a multi-split air conditioner as an example.

[0121] It's important to note that multi-split systems, with their numerous indoor units and complex, long piping connections, require a large amount of refrigerant to be filled. This complexity and the large number of indoor units can lead to miscalculation, resulting in either too much or too little refrigerant in the system. Furthermore, multi-split systems typically have numerous welds, and installation quality varies widely. Failure to maintain pressure long enough before refrigerant filling can lead to micro-leakage during system startup or refrigerant leakage through the high-pressure system after a period of operation, resulting in refrigerant shortages. Excessive refrigerant levels can, in severe cases, cause liquid backflow, leading to liquid compression, or excessive system pressure, triggering a high-pressure shutdown. Low refrigerant levels can lead to a refrigerant shortage in the indoor units, resulting in insufficient capacity and an inability to meet user cooling and heating needs. Furthermore, excessive overheating can trigger high-discharge temperature or low-pressure shutdowns. Therefore, determining the appropriate amount of refrigerant in the system is crucial for practical engineering applications. In related technologies, the system refrigerant quantity is mainly determined by the compressor exhaust, the compressor exhaust superheat, the system high and low pressures, the compressor return air superheat, etc. However, in complex usage environments, misjudgments may sometimes occur. However, the present application determines the refrigerant quantity based on the temperature parameters of the outdoor and indoor units and the refrigerant judgment parameters when the multi-split air conditioner meets the refrigerant diagnosis conditions. This makes the refrigerant quantity determination more accurate and facilitates timely handling by installation and after-sales personnel when the refrigerant quantity is insufficient, thus avoiding the impact of excessive or insufficient refrigerant on the reliability and comfort of the system.

[0122] It should be understood that before the program starts, it is necessary to first determine whether the multi-split air conditioner meets the starting conditions of the refrigerant diagnosis function. Specifically, to determine whether the refrigerant diagnosis conditions are met, the multi-split air conditioner must first be initialized and run, and then it is determined whether the rated capacity of the indoor units participating in the diagnosis meets the comprehensive conditions.

[0123] Furthermore, in order to determine whether the multi-split air conditioner meets the refrigerant diagnosis conditions, in step S10, it is first determined that the multi-split air conditioner enters the refrigerant diagnosis function, and then the outdoor fan of the outdoor unit is controlled to run according to the target wind speed for an initial stable time. Specifically, the outdoor fan is controlled to run at a high wind speed for a period of time TIME1, so that the outdoor return air temperature sensor T4 can detect accurately.

[0124] In one embodiment, after the multi-split air conditioner completes initialization operation, the indoor units that need to undergo refrigerant quantity diagnosis are determined from among the indoor units as target indoor units. The target indoor units are pre-set or selected by the user and can be any number of indoor units. This embodiment does not impose any limitation on this.

[0125] It should be noted that, after the target indoor units are determined, the rated capacity of each target indoor unit is calculated, and the stable capacity of the outdoor units in the multi-split air conditioner is obtained.

[0126] It should be understood that the total rated capacity of the target indoor units is required to be R% of the rated capacity of the outdoor units (R is generally 80-120, for example, 100). At this time, it is determined that the multi-split air conditioner meets the refrigerant diagnosis conditions, so the step of obtaining the outdoor ambient temperature of the outdoor unit is entered.

[0127] In this way, it is possible to determine whether the multi-split air conditioner meets the diagnostic prerequisites before performing refrigerant quantity diagnosis, thereby preventing misjudgment.

[0128] The parameter calculation module 20 is used to determine the operation mode of the multi-split air conditioner according to the outdoor ambient temperature, and calculate the refrigerant judgment parameter and the temperature difference parameter according to the operation mode.

[0129] In one embodiment, determining the operating mode of the multi-split air conditioner based on the outdoor ambient temperature means determining whether the multi-split air conditioner is in heating mode or cooling mode based on the specific value of the outdoor ambient temperature, and then calculating different refrigerant judgment parameters and temperature difference parameters according to different operating modes.

[0130] The refrigerant diagnosis module 30 is configured to determine the amount of refrigerant based on the refrigerant determination parameter and the temperature difference parameter.

[0131] It should be noted that after the refrigerant judgment parameter and the temperature difference parameter are determined, the refrigerant judgment parameter is compared with the opening comparison threshold range, and the temperature difference parameter is compared with the temperature comparison threshold range, and the refrigerant amount is judged and diagnosed based on the two comparison results.

[0132] Further, in order to accurately determine the refrigerant amount, in step S30, the opening comparison threshold range is first selected according to the refrigerant judgment parameter. Specifically, different opening comparison threshold ranges and temperature comparison threshold ranges are determined according to the operating mode of the multi-connected air conditioner.

[0133] It should be understood that in the refrigeration mode, first determine Rp as the refrigerant judgment parameter, and Rp0 and Rp1 are preset reference thresholds, that is, the opening comparison threshold range.

[0134] Therefore, the steps of comparing the refrigerant judgment parameter with the opening comparison threshold range in the refrigeration mode include: Rp is greater than Rp1. If Rp >= Rp0, it is prompted that the refrigerant is severely insufficient, and the process ends; otherwise, go to the next step. If Rp >= Rp1, it is prompted that the refrigerant is insufficient, and the process ends; otherwise, go to the next step.

[0135] In one embodiment, in the refrigeration mode, the temperature comparison threshold range is determined to be a threshold range less than A, and A can be any preset temperature threshold. Therefore, the determination method of the temperature comparison result in the refrigeration mode is: if TCavg - T3avg < A, it is prompted that the refrigerant amount is in the normal range, and the process ends; otherwise, it is prompted that there is too much refrigerant, and the process ends. Where TCavg is the average value of the high-pressure saturation temperature, and T3avg is the average value of the refrigerant outlet temperature of the outdoor unit.

[0136] It should be noted that in the heating mode, first determine Poavg as the refrigerant judgment parameter. At this time, the opening comparison threshold range is composed of three thresholds P0, P1, and P2, where P0, P1, and P2 are arbitrarily increasing values. Therefore, the judgment steps of the opening comparison result are: if Poavg <= P0, it is prompted that there is too much refrigerant, and the process ends; otherwise, go to the next step. If Poavg <= P1, it is prompted that there is too much refrigerant, and the process ends; otherwise, go to the next step. If Poavg <= P2, it is prompted that the refrigerant amount is in the normal range, and the process ends; otherwise, go to the next step.

[0137] It should be understood that in the heating mode, the temperature comparison threshold range is determined to be a value range less than B, where B can be any preset temperature threshold. Therefore, the determination method of the temperature comparison result in the heating mode is: if TCavg - TAavg < B, it is prompted that the refrigerant is severely insufficient, and the process ends; otherwise, it is prompted that the refrigerant is insufficient, and the process ends. Where TCavg is the average value of the high-pressure saturation temperature, and TAavg is the average value of the heat exchanger inlet temperature.

[0138] In this way, the parameters participating in the refrigerant diagnosis can be processed in intervals according to the corresponding outdoor return air temperature T4 (for each T4 interval, different parameter values can be taken), so as to accurately determine the refrigerant amount.

[0139] This application realizes the determination of the refrigerant quantity based on the temperature parameters of the outdoor unit and indoor unit and the refrigerant judgment parameters when the multi-split air conditioner meets the refrigerant diagnosis conditions, so that the determination of the refrigerant quantity is more accurate, and it is convenient for the installation and after-sales personnel to deal with it in time when the refrigerant quantity is insufficient, avoiding the impact of too much or too little refrigerant on the reliability and comfort of the system.

[0140] It should be understood that the above is only an example and does not constitute any limitation to the technical solution of the present application. In specific applications, technicians in this field can make settings as needed, and the present application does not impose any restrictions on this.

[0141] It should be noted that the workflow described above is merely illustrative and does not limit the scope of protection of this application. In actual applications, technicians in this field can select part or all of it according to actual needs to achieve the purpose of this embodiment scheme, and no restrictions are imposed here.

[0142] In addition, for technical details not fully described in this embodiment, please refer to the refrigerant diagnosis method provided in any embodiment of the present application, and will not be repeated here.

[0143] In addition, it should be noted that, in this document, the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or system comprising a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or system. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or system comprising the element.

[0144] The serial numbers of the above embodiments of the present application are for description only and do not represent the advantages or disadvantages of the embodiments.

[0145] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus the necessary general hardware platform. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of this application, or the part that contributes to the existing technology, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as read-only memory (ROM) / RAM, a magnetic disk, or an optical disk) and includes a number of instructions for enabling a terminal device (which can be a mobile phone, a computer, a server, or a network device, etc.) to execute the methods described in each embodiment of this application.

[0146] The above are merely optional embodiments of the present application and do not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A refrigerant diagnostic method, wherein: The refrigerant diagnosis method is applied to a multi-split air conditioner, wherein the multi-split air conditioner includes an outdoor unit and a plurality of indoor units. The refrigerant diagnosis method for the air conditioner includes: When the multi-split air conditioner meets the refrigerant diagnosis condition, obtaining the outdoor ambient temperature of the outdoor unit; Determining the operating mode of the multi-split air conditioner according to the outdoor ambient temperature, and calculating the refrigerant determination parameter and the temperature difference parameter according to the operating mode; and The amount of refrigerant is determined based on the refrigerant determination parameter and the temperature difference parameter.

2. The refrigerant diagnostic method according to claim 1, wherein: When the multi-split air conditioner meets the refrigerant diagnosis condition, obtaining the outdoor ambient temperature of the outdoor unit includes: When the multi-split air conditioner enters the refrigerant diagnosis function, the outdoor fan of the outdoor unit is controlled to run according to the target windshield for an initial stable time; Determining a target indoor unit from among the indoor units, the target indoor unit being the indoor unit participating in the refrigerant diagnosis; Calculating the sum of the indoor unit rated capacity of each target indoor unit and the outdoor unit rated capacity of the outdoor unit; and When the ratio of the sum of the rated capacities of the indoor units to the rated capacities of the outdoor units is a preset ratio, it is determined that the multi-split air conditioner meets the refrigerant diagnosis condition, and the outdoor ambient temperature of the outdoor unit is obtained.

3. The refrigerant diagnostic method according to claim 1, wherein: The step of determining the operating mode of the multi-split air conditioner according to the outdoor ambient temperature, and calculating the refrigerant determination parameter and the temperature difference parameter according to the operating mode, comprises: When the outdoor ambient temperature meets a preset temperature range, determining that the operation mode of the multi-split air conditioner is a cooling mode; Obtaining the expansion valve opening degree, high pressure saturation temperature and condenser outlet temperature of each indoor unit in the first preset time period; Determining a refrigerant determination parameter according to the expansion valve opening; and A temperature difference parameter is calculated based on the high-pressure saturation temperature and the condenser outlet temperature, wherein the temperature difference parameter is a difference between an average value of the high-pressure saturation temperature and an average value of the condenser outlet temperature.

4. The refrigerant diagnosis method according to claim 3, wherein: When the outdoor ambient temperature meets the preset temperature range, after determining that the operation mode of the multi-split air conditioner is the cooling mode, the method further includes: Obtaining the expansion valve opening of the turned-on indoor unit in each indoor unit, the condenser outlet temperature of the outdoor unit, and the return air temperature of the outdoor unit; Determining a refrigerant determination parameter according to the expansion valve opening; and A temperature difference parameter is calculated based on the outdoor unit return air temperature and the condenser outlet temperature, and the temperature difference parameter is the difference between the average value of the outdoor unit return air temperature and the average value of the condenser outlet temperature.

5. The refrigerant diagnostic method according to claim 3, wherein: The step of determining the refrigerant judgment parameter according to the expansion valve opening comprises: Calculating an average opening degree according to the expansion valve opening degree; Reading the minimum refrigeration opening of the expansion valve of each powered-on indoor unit, and calculating the minimum opening average of the minimum refrigeration opening; and A refrigerant judgment parameter is calculated according to the average opening value and the minimum opening value, and the refrigerant judgment parameter is a ratio of the average opening value to the minimum opening value.

6. The refrigerant diagnostic method according to claim 1, wherein: The step of determining the operating mode of the multi-split air conditioner according to the outdoor ambient temperature, and calculating the refrigerant determination parameter and the temperature difference parameter according to the operating mode, comprises: When the outdoor ambient temperature does not meet the preset temperature range, determining that the operation mode of the multi-split air conditioner is a heating mode; Obtaining the heat exchanger inlet temperature, high pressure saturation temperature and main expansion valve opening of each indoor unit in the second preset time period; Calculate the average inlet temperature of each heat exchanger inlet temperature, the average main expansion valve opening of the main expansion valve opening, and the average saturation temperature of the high-pressure saturation temperature; Determining a refrigerant determination parameter according to the average value of the inlet temperature; and A temperature difference parameter is determined according to the average opening degree of the main expansion valve and the average saturation temperature.

7. The refrigerant diagnostic method according to any one of claims 1 to 6, wherein: The determining the amount of refrigerant based on the refrigerant determination parameter and the temperature difference parameter includes: Selecting an opening comparison threshold range according to the refrigerant judgment parameter; Selecting a temperature comparison threshold range according to the temperature difference parameter; Comparing the refrigerant judgment parameter with the opening comparison threshold range to obtain an opening comparison result, and comparing the temperature difference parameter with the temperature comparison threshold range to obtain a temperature comparison result; and The amount of refrigerant of the multi-split air conditioner is determined based on the opening comparison result and the temperature comparison result.

8. A refrigerant diagnostic device, wherein: The refrigerant diagnostic device comprises: A temperature acquisition module, used for acquiring the outdoor ambient temperature of the outdoor unit when the multi-split air conditioner meets the refrigerant diagnosis condition; a parameter calculation module, configured to determine an operation mode of the multi-split air conditioner according to the outdoor ambient temperature, and calculate a refrigerant determination parameter and a temperature difference parameter according to the operation mode; and The refrigerant diagnosis module is used to determine the amount of refrigerant based on the refrigerant judgment parameter and the temperature difference parameter.

9. A multi-split air conditioner, wherein: The multi-split air conditioner includes: a memory, a processor, and a refrigerant diagnostic program stored in the memory and running on the processor, wherein the refrigerant diagnostic program is configured to implement the refrigerant diagnostic method according to any one of claims 1 to 7.

10. A storage medium, wherein: The storage medium stores a refrigerant diagnostic program, and when the refrigerant diagnostic program is executed by the processor, the refrigerant diagnostic method according to any one of claims 1 to 7 is implemented.

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