An air conditioning system return air short circuit detection method and detection device, and an air conditioning system

Abstract

The application discloses an air conditioning system return air short circuit detection method and device and an air conditioning system. The air conditioning system return air short circuit detection method comprises the following steps: when the air conditioning system is started and runs to be stable, the return air temperature, the pipeline temperature and the ambient temperature of the air conditioning system are detected; the first difference value between the return air temperature and the ambient temperature is calculated, and whether the air conditioning system is abnormal in return air is judged according to the first difference value; when it is judged that the air conditioning system is abnormal in return air, the second difference value between the return air temperature and the pipeline temperature is calculated, and whether the air conditioning system is short-circuited in return air is judged according to the second difference value. Compared with the prior art, the application can detect whether the air conditioning system is short-circuited in return air when the air conditioning system is running, verify whether the installation position of the unit is reasonable, facilitate the installation personnel to adjust the installation position, avoid the short circuit in return air and improve the reliability of the unit.

Description

Technical Field

[0001] This invention relates to the field of air conditioning, and in particular to a method and device for detecting short circuits in the return air of an air conditioning system, and an air conditioning system. Background Technology

[0002] Currently, ducted air conditioners, ceiling-mounted air conditioners, and other light commercial air conditioners often experience short-circuit return air during actual use.

[0003] Return air short circuit: This means that the air blown out of the air outlet is drawn back into the return air, causing a short circuit between the air outlet and the return air. A slight short circuit will lead to a decrease in cooling and heating effects. When the air outlet-return air short circuit becomes severe, it will cause the indoor unit to freeze and the protection function to fail, and the high pressure protection function to be triggered due to excessive heating pressure. Long-term operation with a return air short circuit will also cause wear and tear on the compressor due to liquid return, and overload.

[0004] Short circuits in return air are mostly caused by poor installation location or improper installation, which means they occur during the installation and commissioning stage. This leads to a series of installation problems such as obstructed airflow or short distance and similar direction between the airflow outlet and return air, causing the airflow outlet to be drawn back to the return air location.

[0005] Currently, the detection and handling of return air short circuits in indoor units are mostly focused on ceiling-mounted units, and the vent operation after a return air short circuit occurs to solve the problem. However, the problem cannot be reported to the installers during the trial operation phase of installation and commissioning, so as to detect the problem in a timely manner. Summary of the Invention

[0006] In view of the problem that existing technologies cannot report the existence of return air short circuits to installers during the trial operation of the installation and commissioning phase, this invention proposes a method and device for detecting return air short circuits in air conditioning systems, as well as an air conditioning system.

[0007] The technical solution of the present invention is to propose a method for detecting short circuit in the return air of an air conditioning system. When the air conditioning system is turned on and runs to a stable state, the return air temperature, pipe temperature and ambient temperature of the air conditioning system are detected.

[0008] Calculate the first difference between the return air temperature and the ambient temperature, and determine whether the air conditioning system has an abnormal return air condition based on the first difference.

[0009] When the return air of the air conditioning system is determined to be abnormal, a second difference between the return air temperature and the duct temperature is calculated, and the air conditioning system is judged to be short-circuited based on the second difference.

[0010] Furthermore, the air conditioning system includes a cooling mode and a heating mode, and when the air conditioning system is in cooling mode, determining whether the air conditioning system has an abnormal return air condition based on the first difference includes:

[0011] Determine whether the first difference is less than the first threshold temperature difference;

[0012] If so, the air return air of the air conditioning system is determined to be abnormal.

[0013] Furthermore, when the air conditioning system is in heating mode, determining whether the air conditioning system has an abnormal return air condition based on the first difference includes:

[0014] Determine whether the first difference is greater than the third threshold temperature difference;

[0015] If so, the air return air of the air conditioning system is determined to be abnormal.

[0016] Furthermore, when the air conditioning system is in cooling mode, determining whether the air conditioning system has a return air short circuit based on the second difference includes:

[0017] Determine whether the second difference is less than the second threshold temperature difference;

[0018] If so, the air conditioning system is determined to be short-circuited in return air.

[0019] Furthermore, when the air conditioning system is in heating mode, determining whether the air conditioning system has a return air short circuit based on the second difference includes:

[0020] Determine whether the second difference is greater than the fourth threshold temperature difference;

[0021] If so, the air conditioning system is determined to be short-circuited in return air.

[0022] Furthermore, the first threshold temperature difference ranges from -5℃ to 0℃;

[0023] The second threshold temperature difference ranges from -4℃ to 4℃.

[0024] Furthermore, the value range of the third threshold temperature difference is 0℃~10℃;

[0025] The fourth threshold temperature difference ranges from -2℃ to 0℃.

[0026] Furthermore, when the air conditioning system is in cooling mode, determining whether the air conditioning system has a return air short circuit based on the second difference also includes:

[0027] Detect the operating position of the indoor unit of the air conditioning system;

[0028] The second threshold temperature difference is compensated according to the operating setting, and the air conditioning system is judged to have a return air short circuit based on the compensated second threshold temperature difference.

[0029] Furthermore, when the air conditioning system is in heating mode, determining whether the air conditioning system has a return air short circuit based on the second difference also includes:

[0030] Detect the operating position of the indoor unit of the air conditioning system;

[0031] The fourth threshold temperature difference is compensated according to the operating setting, and the return air short circuit of the air conditioning system is determined based on the compensated fourth threshold temperature difference.

[0032] Furthermore, the indoor unit of the air conditioning system has four operating settings, and when the indoor unit is operating at the first setting, the compensation value for compensating the second threshold temperature difference is the first compensation value.

[0033] When the indoor unit of the air conditioner is working at the second setting, the compensation value for compensating the second threshold temperature difference is the second compensation value.

[0034] When the indoor unit of the air conditioner is working at the third setting, the compensation value for compensating the second threshold temperature difference is the third compensation value.

[0035] When the indoor unit of the air conditioner is operating at the fourth setting, the compensation value for compensating the second threshold temperature difference is the fourth compensation value.

[0036] Furthermore, the indoor unit of the air conditioning system has four operating levels, and when the indoor unit is operating at the first level, the compensation value for compensating the fourth threshold temperature difference is the fifth compensation value.

[0037] When the indoor unit of the air conditioner is working at the second setting, the compensation value for compensating the fourth threshold temperature difference is the sixth compensation value.

[0038] When the indoor unit of the air conditioner is working at the third setting, the compensation value for compensating the fourth threshold temperature difference is the seventh compensation value.

[0039] When the indoor unit of the air conditioner is operating at the fourth setting, the compensation value for compensating the fourth threshold temperature difference is the eighth compensation value.

[0040] Furthermore, the first compensation value is 0, the second compensation value, the third compensation value, and the fourth compensation value are all within the range of 0 to 5°C, and the second compensation value is less than the third compensation value, and the third compensation value is less than the fourth compensation value.

[0041] Furthermore, the fifth compensation value is 0, and the values ​​of the sixth, seventh, and eighth compensation values ​​are in the range of -5 to 0℃, with the sixth compensation value being greater than the seventh compensation value and the seventh compensation value being greater than the eighth compensation value.

[0042] Furthermore, when the air conditioning system is equipped with an outlet air temperature sensor, the air conditioning system return air short-circuit detection method further includes the following when an abnormality in the air conditioning system return air is determined:

[0043] Detect the outlet air temperature of the air conditioning system;

[0044] The return air short-circuit ratio of the air conditioning system is calculated based on the outlet air temperature, the return air temperature, and the ambient temperature.

[0045] The return air status of the air conditioning system is determined based on the return air short-circuit ratio.

[0046] Furthermore, the calculation model for the return air short-circuit ratio is as follows:

[0047] Ф=(T_return_air - T_ambient_air) / (T_exhaust_air - T_ambient_air)

[0048] Wherein, Ф is the return air short-circuit ratio, T_return air is the return air temperature, and T_outlet air is the outlet air temperature.

[0049] T_environment refers to the ambient temperature.

[0050] Furthermore, when the air conditioning system is in cooling mode, the return air status of the air conditioning system is determined based on the return air short-circuit ratio, including:

[0051] The return air short-circuit ratio is compared with a first preset ratio and a second preset ratio, and the preset range in which the return air short-circuit ratio falls is determined.

[0052] When the return air short-circuit ratio is within the first preset range, the air return of the air conditioning system is determined to be normal.

[0053] When the return air short-circuit ratio is within the second preset range, it is determined that the air conditioning system has a return air short circuit.

[0054] When the return air short-circuit ratio is in the third preset range, the air conditioning system is determined to be faulty.

[0055] Furthermore, when the air conditioning system is in heating mode, the return air status of the air conditioning system is determined based on the return air short-circuit ratio, including:

[0056] The return air short-circuit ratio is compared with a third preset ratio and a fourth preset ratio, and the preset range in which the return air short-circuit ratio falls is determined.

[0057] When the return air short-circuit ratio is within the fourth preset range, the return air of the air conditioning system is determined to be normal.

[0058] When the return air short-circuit ratio is in the fifth preset range, it is determined that the air conditioning system has a return air short circuit;

[0059] When the return air short-circuit ratio is in the sixth preset range, the air conditioning system is determined to be faulty.

[0060] Furthermore, the first preset ratio ranges from 10% to 40%, and the second preset ratio ranges from 40% to 70%.

[0061] The first preset interval is 0 to Φ1, the second preset interval is Φ1 to Φ2, and the third preset interval is Φ2 to 1;

[0062] Wherein, Φ1 is the first preset ratio and Φ2 is the second preset ratio.

[0063] Furthermore, the third preset ratio ranges from 10% to 40%, and the fourth preset ratio ranges from 40% to 70%.

[0064] The fourth preset interval is 0 to Φ3, the fifth preset interval is Φ3 to Φ4, and the sixth preset interval is Φ3 to 1;

[0065] Wherein, Φ3 is the third preset ratio and Φ4 is the fourth preset ratio.

[0066] The present invention also proposes an air conditioning system return air short circuit detection device using the above-mentioned air conditioning system return air short circuit detection method, comprising: a return air temperature sensor for detecting return air temperature, a wired controller temperature sensor for detecting ambient temperature, a pipe temperature sensor for detecting pipe temperature, and an outlet air temperature sensor for detecting outlet air temperature.

[0067] The air conditioning system return air short circuit detection device determines whether the air conditioning system has an abnormal return air by calculating the temperature difference between the return air temperature sensor and the wired controller temperature sensor.

[0068] The system determines whether the air conditioning system has a return air short circuit by calculating the temperature difference between the return air temperature sensor and the pipe temperature sensor.

[0069] The present invention also proposes an air conditioning system having the aforementioned air conditioning system return air short circuit detection device.

[0070] Compared with the prior art, the present invention has at least the following beneficial effects:

[0071] 1. This invention can determine whether the air conditioning system has a return air short circuit by using the first difference and the second difference during trial operation, thereby verifying whether the unit installation position is reasonable. Problems can be identified during the installation stage, making it convenient for installers to adjust the installation position.

[0072] 2. This invention can detect and report whether the air conditioning system has a return air short circuit, which can avoid the problem of low heat exchange efficiency and poor actual use effect when the air conditioning is used, thus improving the reliability of the unit. Attached Figure Description

[0073] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0074] Figure 1 This is a flowchart illustrating the detection process for air outlet short circuit in the air conditioning system during cooling mode in this invention.

[0075] Figure 2 This is a flowchart illustrating the detection process for air outlet short circuit in the air conditioning system during heating mode in this invention.

[0076] Figure 3 This is a flowchart illustrating the compensation process for the second threshold temperature difference in the air conditioning system during cooling mode in this invention.

[0077] Figure 4 This is a flowchart illustrating the compensation process for the fourth threshold temperature difference in the heating mode of the air conditioning system in this invention.

[0078] Figure 5 This is a flowchart illustrating the detection process for air outlet short circuit in cooling mode when the air conditioning system of this invention is equipped with an air outlet temperature sensor.

[0079] Figure 6 This is a flowchart illustrating the detection process for air outlet short circuit in heating mode when the air conditioning system of this invention is equipped with an air outlet temperature sensor. Detailed Implementation

[0080] To make the technical problems to be solved, the technical solutions, and the beneficial effects of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and are not intended to limit the present invention.

[0081] Therefore, a feature pointed out in this specification is used to describe one feature of one embodiment of the invention, and does not imply that every embodiment of the invention must have the described feature. Furthermore, it should be noted that this specification describes many features. Although certain features may be combined to illustrate possible system designs, these features may also be used in other combinations not explicitly stated. Therefore, unless otherwise stated, the described combinations are not intended to be limiting.

[0082] The principles and structure of the present invention will be described in detail below with reference to the accompanying drawings and embodiments.

[0083] Currently, ducted and ceiling-mounted air conditioners, and other light commercial air conditioning systems, frequently experience return air short circuits during actual use. However, it's not currently possible to detect these short circuits during system trial operation. The present invention aims to determine the presence of a return air short circuit by detecting a first difference between the return air temperature and the ambient temperature, and a second difference between the return air temperature and the duct temperature. This allows for detection during trial operation, facilitating adjustments to the installation location by installers.

[0084] The technical solution of this invention is to propose a method for detecting short circuits in the return air of an air conditioning system, comprising:

[0085] When the air conditioning system is turned on and running until it is stable, measure the return air temperature, pipe temperature, and ambient temperature of the air conditioning system.

[0086] Calculate the first difference between the return air temperature and the ambient temperature, and determine whether the air conditioning system has an abnormal return air condition based on the first difference.

[0087] When an abnormality is detected in the air conditioning system return air, the second difference between the return air temperature and the duct temperature is calculated, and the air conditioning system is judged to be short-circuited based on the second difference.

[0088] This invention can determine whether a return air short circuit has occurred in the air conditioning system by using the first difference and the second difference. It can detect whether there is a return air short circuit problem in the air conditioning system during the trial run, thus making it easier for installers to adjust the installation position.

[0089] The air conditioning system includes a cooling mode and a heating mode. When the air conditioning system is in cooling mode, a first difference is used to determine whether the air return air of the air conditioning system is abnormal, including:

[0090] Determine whether the first difference is less than the first threshold temperature difference;

[0091] If so, the air conditioning system return air is determined to be abnormal.

[0092] In cooling mode, when the air conditioning system is operating normally, its return air temperature is equal to the ambient temperature. However, when the air conditioning system experiences a return air short circuit, the cold air blown out by the cooling system will be drawn back to the return air, which will cause the return air temperature to drop. Therefore, when the return air temperature is lower than the ambient temperature, it indicates that the air conditioning system's return air is abnormal and further testing is required.

[0093] The first threshold temperature difference is set according to the actual operating conditions. By comparing the first difference with the first threshold temperature difference, the present invention can quickly identify whether the air conditioning system has abnormal return air. The judgment process is simple and can be carried out during the trial operation phase.

[0094] Furthermore, when the air conditioning system is in cooling mode, the system is judged to be in a return air short circuit based on the second difference, including:

[0095] Determine whether the second difference is less than the second threshold temperature difference;

[0096] If so, the air conditioning system return air is determined to be short-circuited.

[0097] This detection process is only performed when the air conditioning system return air is abnormal, in order to save judgment steps. The second threshold temperature difference is set according to the actual operating conditions. If the second difference is less than the second threshold temperature difference, it indicates that a large amount of cold air is being drawn back (normally the return air temperature will be higher than the pipe temperature. Only when a return air short circuit occurs will the temperature difference between the return air temperature and the pipe temperature decrease). This indicates that a return air short circuit has occurred.

[0098] Please see Figure 1 This is a flowchart illustrating the detection process for a short circuit in the return air of an air conditioning system under cooling mode, as described in this invention. T 回风 T represents the return air temperature. 环温 For ambient temperature, T 管温 n1 is the pipeline temperature, n2 is the first threshold temperature difference, n2 is the second threshold temperature difference, ΔT is the first difference, and ΔT* is the second difference.

[0099] In cooling mode, the compressor is first run for S1 minutes to ensure that the air conditioning system is turned on and runs stably. Then, the first difference is calculated by the return air temperature and the ambient temperature, and it is determined whether the first difference is less than the first threshold temperature difference. If the first difference is less than the first threshold temperature difference, it is determined that the return air is abnormal. The second difference is then calculated by the return air temperature and the pipe temperature, and it is determined whether the second difference is less than the second threshold temperature difference. If the second difference is less than the second threshold temperature difference, it is determined that the air conditioning system has a return air short circuit.

[0100] S1 is the time it takes for the air conditioning system to reach a relatively stable state, which is generally set to 10 to 30 minutes. The value of n1 ranges from -5℃ to 0℃, meaning that the judgment is only made when the return air temperature is lower than the ambient temperature.

[0101] The value of n2 ranges from -4℃ to 4℃.

[0102] Through the above steps, this invention enables testing during trial operation, making it convenient for installers to adjust the installation position.

[0103] When the air conditioning system is in heating mode, the system determines whether there is an abnormal return air condition based on the first difference, including:

[0104] Determine whether the first difference is greater than the third threshold temperature difference;

[0105] If so, the air return air of the air conditioning system is determined to be abnormal.

[0106] In heating mode, when the air conditioning system is operating normally, its return air temperature is equal to the ambient temperature. However, when the air conditioning system experiences a return air short circuit, the hot air blown out during heating will be drawn back to the return air, causing the return air temperature to rise. Therefore, when the return air temperature is higher than the ambient temperature, it indicates that the air conditioning system's return air is abnormal and further testing is required.

[0107] The third threshold temperature difference is set according to the actual operating conditions. By comparing the first difference with the third threshold temperature difference, the present invention can quickly identify whether the air conditioning system has abnormal return air. The judgment process is simple and can be carried out during the trial operation phase.

[0108] Furthermore, when the air conditioning system is in heating mode, the system determines whether there is a return air short circuit based on the second difference, including:

[0109] Determine whether the second difference is greater than the fourth threshold temperature difference;

[0110] If so, the air conditioning system is determined to be short-circuited in return air.

[0111] This detection process is only performed when the air conditioning system return air is abnormal, in order to save judgment steps. The fourth threshold temperature difference is set according to the actual operating conditions. If the second difference is greater than the fourth threshold temperature difference, it indicates that a large amount of hot air is being drawn back (normally the return air temperature is lower than the pipe temperature. Only when a return air short circuit occurs will the temperature difference between the return air temperature and the pipe temperature decrease). This can be considered as a return air short circuit.

[0112] Please see Figure 2 This is a flowchart illustrating the detection process for a short circuit in the return air of an air conditioning system under heating mode, as described in this invention. T 回风 T represents the return air temperature. 环温 For ambient temperature, T 管温 n is the pipeline temperature, n3 is the third threshold temperature difference, n4 is the fourth threshold temperature difference, ΔT is the first difference, and ΔT* is the second difference.

[0113] In heating mode, the compressor is first run for S2 minutes to ensure that the air conditioning system is turned on and runs stably. Then, the first difference is calculated by the return air temperature and the ambient temperature, and it is determined whether the first difference is greater than the third threshold temperature difference. If the first difference is greater than the third threshold temperature difference, it is determined that the return air is abnormal. The second difference is further calculated by the return air temperature and the pipe temperature, and it is determined whether the second difference is greater than the fourth threshold temperature difference. If the second difference is greater than the fourth threshold temperature difference, it is determined that the air conditioning system has a return air short circuit.

[0114] S2 is the time it takes for the air conditioning system to reach a relatively stable state, which is generally set to 10 to 30 minutes. The value of n3 ranges from -5℃ to 0℃, meaning that the judgment is only made when the return air temperature is lower than the ambient temperature.

[0115] The value of n4 ranges from -4℃ to 4℃.

[0116] Through the above steps, this invention enables testing during trial operation, making it convenient for installers to adjust the installation position.

[0117] Furthermore, when the air conditioning system is in cooling mode, determining whether the air conditioning system has a return air short circuit based on the second difference also includes:

[0118] Check the operating position of the indoor unit of the air conditioning system;

[0119] The second threshold temperature difference is compensated based on the operating setting, and the return air short circuit of the air conditioning system is determined based on the compensated second threshold temperature difference.

[0120] Here, since the air conditioning system has multiple operating levels and the return air power is different in each operating level, it is also necessary to compensate for the second threshold temperature difference according to the actual operating level. Specifically, when the air conditioning system is in cooling mode, the indoor unit of the air conditioning system has four operating levels, and when the indoor unit is working at the first level, the compensation value for compensating for the second threshold temperature difference is the first compensation value.

[0121] When the indoor unit of the air conditioner is working at the second setting, the compensation value for compensating for the second threshold temperature difference is the second compensation value.

[0122] When the indoor unit of the air conditioner is working at the third setting, the compensation value for compensating for the second threshold temperature difference is the third compensation value.

[0123] When the indoor unit of the air conditioner is operating at the fourth setting, the compensation value for compensating for the second threshold temperature difference is the fourth compensation value.

[0124] By using the above method, the present invention can compensate for the second threshold temperature difference based on the operating setting of the indoor unit of the air conditioning system, thereby further improving the reliability of the air conditioning system in detecting return air short circuits.

[0125] The first compensation value is 0, and the values ​​of the second, third, and fourth compensation values ​​are in the range of 0 to 5℃. The second compensation value is less than the third compensation value, and the third compensation value is less than the fourth compensation value.

[0126] Please see Figure 3 This is a flowchart illustrating the compensation process of the air conditioning system of the present invention for compensating for the second threshold temperature difference in cooling mode, wherein T 回风 T represents the return air temperature. 环温The ambient temperature is n1, the first threshold temperature difference is n2, the second threshold temperature difference is n2, the first difference is ΔT, the first gear is ultra-high, the second gear is high, the third gear is medium, the fourth gear is low, the second compensation value is a, the third compensation value is b, and the fourth compensation value is c.

[0127] In cooling mode, the compressor is first run for S1 minutes to ensure that the air conditioning system is turned on and runs to a stable state. Then, the first difference is calculated by the return air temperature and the ambient temperature, and it is determined whether the first difference is less than the first threshold temperature difference. If the first difference is less than the first threshold temperature difference, it is determined that the return air is abnormal.

[0128] Then, based on the operating setting of the indoor unit of the air conditioning system, the second threshold temperature difference is compensated. Here, the difference is calculated. Since the first compensation value is 0, the second threshold temperature difference is still used for judgment in the first setting. In the second, third, and fourth settings, the difference between the second threshold temperature difference and its corresponding compensation value is used for judgment.

[0129] If the second difference at this time, that is, the difference between the return air temperature and the pipeline temperature, is less than the compensated second threshold temperature difference, then it can be determined that a return air short circuit has occurred.

[0130] By using the above method, the present invention can compensate for the second threshold temperature difference based on the operating setting of the indoor unit of the air conditioning system, thereby further improving the reliability of the air conditioning system in detecting return air short circuits.

[0131] Furthermore, when the air conditioning system is in heating mode, determining whether the air conditioning system has a return air short circuit based on the second difference also includes:

[0132] Check the operating position of the indoor unit of the air conditioning system;

[0133] The fourth threshold temperature difference is compensated based on the operating setting, and the return air short circuit of the air conditioning system is determined based on the compensated fourth threshold temperature difference.

[0134] Here, since the air conditioning system has multiple operating levels and the return air power is different in each operating level, it is also necessary to compensate for the fourth threshold temperature difference according to the actual operating level. Specifically, when the air conditioning system is in heating mode, the indoor unit of the air conditioning system has four operating levels, and when the indoor unit is working at the first level, the compensation value for the fourth threshold temperature difference is the fifth compensation value.

[0135] When the indoor unit of the air conditioner is working at the second setting, the compensation value for compensating for the fourth threshold temperature difference is the sixth compensation value.

[0136] When the indoor unit of the air conditioner is working at the third setting, the compensation value for compensating for the fourth threshold temperature difference is the seventh compensation value.

[0137] When the indoor unit of the air conditioner is operating at the fourth setting, the compensation value for compensating for the fourth threshold temperature difference is the eighth compensation value.

[0138] After using the above method, the present invention can compensate for the fourth threshold temperature difference based on the working position of the indoor unit of the air conditioning system, thereby further improving the reliability of the air conditioning system in detecting return air short circuits.

[0139] Among them, the fifth compensation value is 0, and the values ​​of the sixth, seventh and eighth compensation values ​​are in the range of -5 to 0℃, with the sixth compensation value being greater than the seventh compensation value and the seventh compensation value being greater than the eighth compensation value.

[0140] Please see Figure 4 This is a flowchart illustrating the compensation process of the air conditioning system of the present invention for compensating for the fourth threshold temperature difference in heating mode, wherein T 回风 T represents the return air temperature. 环温 n3 is the ambient temperature, n4 is the third threshold temperature difference, n4 is the fourth threshold temperature difference, ΔT is the first difference, the first gear is the ultra-high gear, the second gear is the high gear, the third gear is the medium gear, the fourth gear is the low gear, the sixth compensation value is d, the seventh compensation value is e, and the eighth compensation value is f.

[0141] In heating mode, the compressor is first run for S2 minutes to ensure that the air conditioning system is turned on and runs until it is stable. Then, the first difference is calculated by the return air temperature and the ambient temperature, and it is determined whether the first difference is greater than the third threshold temperature difference. If the first difference is greater than the third threshold temperature difference, it is determined that the return air is abnormal.

[0142] Then, based on the operating setting of the indoor unit of the air conditioning system, the fourth threshold temperature difference is compensated. Here, the difference is calculated. Since the fifth compensation value is 0, the fourth threshold temperature difference is still used for judgment in the first setting. In the second, third, and fourth settings, the difference between the fourth threshold temperature difference and its corresponding compensation value is used for judgment.

[0143] If the second difference, i.e. the difference between the return air temperature and the pipeline temperature, is determined to be less than the compensated fourth threshold temperature difference, then a return air short circuit can be identified.

[0144] By using the above method, the present invention can compensate for the second threshold temperature difference based on the operating setting of the indoor unit of the air conditioning system, thereby further improving the reliability of the air conditioning system in detecting return air short circuits.

[0145] Furthermore, when the air conditioning system is equipped with an outlet air temperature sensor, the air conditioning system return air short-circuit detection method also includes the following when an abnormality in the return air is determined:

[0146] Detect the outlet air temperature of the air conditioning system;

[0147] The return air short-circuit ratio of the air conditioning system is calculated based on the supply air temperature, return air temperature, and ambient temperature.

[0148] The return air status of the air conditioning system is determined by the return air short-circuit ratio.

[0149] Here, when the air conditioning system is equipped with an air outlet temperature sensor, it can accurately detect the outlet air temperature. By measuring the outlet air temperature, return air temperature, ambient temperature, and air volume, the proportion of outlet air being drawn back to return air can be calculated. When the proportion of air being drawn back is large, a return air short circuit has occurred, affecting the performance. When the proportion is large enough, it means that most of the air blown out is drawn back into the return air, affecting the reliability of the unit and requiring shutdown for troubleshooting.

[0150] Therefore, the above method can accurately detect the return air short-circuit ratio and more accurately determine the return air status of the air conditioning system.

[0151] The calculation model for the return air short-circuit ratio is as follows:

[0152] Ф=(T 回风 -T 环境 ) / (T 出风 -T 环境 )

[0153] Where Ф is the return air short-circuit ratio, and T 回风 For return air temperature, T 出风 T represents the outlet air temperature. 环境 The ambient temperature.

[0154] The calculation principle is as follows:

[0155] Total air volume G = Short-circuit air volume G1 + Ambient return air volume G2;

[0156] Since the short-circuit air temperature T1 can be assumed to be the same as the outlet air temperature T 出风 Equal, ambient temperature is the wired controller temperature T 环境 The return air temperature is T 回风 Therefore, we have G1*Cp*T 出风 +G2*Cp*T 环境 =G*Cp*T 回风

[0157] We can obtain Ф=(T) 回风 -T 环境 ) / (T 出风 -T 环境 ).

[0158] When the air conditioning system is in cooling mode, the above-mentioned determination of the return air status of the air conditioning system based on the return air short-circuit ratio includes:

[0159] The return air short-circuit ratio is compared with a first preset ratio and a second preset ratio, and the preset range in which the return air short-circuit ratio falls is determined.

[0160] When the return air short-circuit ratio is within the first preset range, the air conditioning system return air is determined to be normal.

[0161] When the return air short-circuit ratio is in the second preset range, the air conditioning system is determined to be short-circuited in the return air.

[0162] When the return air short-circuit ratio is in the third preset range, the air conditioning system is determined to be faulty.

[0163] By calculating the return air short-circuit ratio using the above method, the return air status of the air conditioning system can be determined more accurately.

[0164] The first preset ratio ranges from 10% to 40%, and the second preset ratio ranges from 40% to 70%.

[0165] The first preset interval is 0 to Φ1, the second preset interval is Φ1 to Φ2, and the third preset interval is Φ2 to 1;

[0166] Wherein, Φ1 is the first preset ratio and Φ2 is the second preset ratio.

[0167] Please see Figure 5 This is a flowchart illustrating the detection process for short circuit in the air outlet during cooling mode when the air conditioning system of this invention is equipped with an outlet air temperature sensor. In this flowchart, T... 回风 T represents the return air temperature. 环温 Where n is the ambient temperature, n1 is the first threshold temperature difference, Φ is the return air short-circuit ratio, Φ1 is the first preset ratio, Φ2 is the second preset ratio, and ΔT is the first difference.

[0168] In cooling mode, the compressor is first run for S1 minutes to ensure that the air conditioning system is turned on and runs to a stable state. Then, the first difference is calculated by the return air temperature and the ambient temperature, and it is determined whether the first difference is less than the first threshold temperature difference. If the first difference is less than the first threshold temperature difference, it is determined that the return air is abnormal.

[0169] Then, the return air short-circuit ratio is calculated, and the return air status is further judged based on the return air short-circuit ratio. When the return air short-circuit ratio is within the first preset range, the return air of the air conditioning system is determined to be normal.

[0170] When the return air short-circuit ratio is in the second preset range, the air conditioning system is determined to be short-circuited in the return air.

[0171] When the return air short-circuit ratio is in the third preset range, the air conditioning system is judged to be faulty, and the return air short circuit is serious.

[0172] In summary, the present invention, through the above-described scheme, can accurately detect the return air short-circuit ratio and more precisely determine the return air status of the air conditioning system.

[0173] When the air conditioning system is in heating mode, the above-mentioned determination of the return air status of the air conditioning system based on the return air short-circuit ratio includes:

[0174] The return air short-circuit ratio is compared with the preset third and fourth preset ratios, and the preset range in which the return air short-circuit ratio falls is determined.

[0175] When the return air short-circuit ratio is in the fourth preset range, the air conditioning system return air is determined to be normal.

[0176] When the return air short-circuit ratio is in the fifth preset range, the air conditioning system is determined to be short-circuited in the return air.

[0177] When the return air short-circuit ratio is in the sixth preset range, the air conditioning system is determined to be faulty.

[0178] By calculating the return air short-circuit ratio using the above method, the return air status of the air conditioning system can be determined more accurately.

[0179] The third preset ratio ranges from 10% to 40%, and the fourth preset ratio ranges from 40% to 70%.

[0180] The fourth preset interval is 0 to Φ3, the fifth preset interval is Φ3 to Φ4, and the sixth preset interval is Φ4 to 1;

[0181] Wherein, Φ3 is the third preset ratio and Φ4 is the fourth preset ratio.

[0182] Please see Figure 6 This is a flowchart illustrating the detection of air outlet short circuit in heating mode when the air conditioning system of this invention is equipped with an air outlet temperature sensor, wherein T 回风 T represents the return air temperature. 环温 Where n is the ambient temperature, n3 is the third threshold temperature difference, Φ is the return air short-circuit ratio, Φ3 is the third preset ratio, Φ4 is the fourth preset ratio, and ΔT is the first difference.

[0183] In heating mode, the compressor is first run for S2 minutes to ensure that the air conditioning system is turned on and runs until it is stable. Then, the first difference is calculated by the return air temperature and the ambient temperature, and it is determined whether the first difference is greater than the third threshold temperature difference. If the first difference is greater than the third threshold temperature difference, it is determined that the return air is abnormal.

[0184] Then, the return air short-circuit ratio is calculated, and the return air status is further judged based on the return air short-circuit ratio. When the return air short-circuit ratio is in the fourth preset range, the return air of the air conditioning system is judged to be normal.

[0185] When the return air short-circuit ratio is in the fifth preset range, the air conditioning system is determined to be short-circuited in the return air.

[0186] When the return air short-circuit ratio is in the sixth preset range, the air conditioning system is judged to be faulty, and the return air short circuit is serious.

[0187] In summary, the present invention, through the above-described scheme, can accurately detect the return air short-circuit ratio and more precisely determine the return air status of the air conditioning system.

[0188] In summary, compared with the prior art, the present invention has at least the following beneficial effects:

[0189] 1. This invention can determine whether the air conditioning system has a return air short circuit by using the first difference and the second difference during trial operation, thereby verifying whether the unit installation position is reasonable. Problems can be identified during the installation stage, making it convenient for installers to adjust the installation position.

[0190] 2. This invention can detect and report whether the air conditioning system has a return air short circuit, which can avoid the problem of low heat exchange efficiency and poor actual use effect when the air conditioning is used, thus improving the reliability of the unit.

[0191] The present invention also proposes an air conditioning system return air short circuit detection device using the above-mentioned air conditioning system return air short circuit detection method, which includes: a return air temperature sensor for detecting return air temperature, a wired controller temperature sensor for detecting ambient temperature, a pipe temperature sensor for detecting pipe temperature, and an outlet air temperature sensor for detecting outlet air temperature.

[0192] The air conditioning system return air short circuit detection device determines whether the air conditioning system has an abnormal return air by calculating the temperature difference between the return air temperature sensor and the temperature sensor of the wired controller.

[0193] The system determines whether the air conditioning system has a return air short circuit by calculating the temperature difference between the return air temperature sensor and the pipe temperature sensor.

[0194] The present invention also proposes an air conditioning system having the aforementioned air conditioning system return air short circuit detection device.

[0195] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for detecting short circuits in the return air of an air conditioning system, characterized in that, include: When the air conditioning system is turned on and running until it is stable, the return air temperature, pipe temperature, and ambient temperature of the air conditioning system are detected. Calculate the first difference between the return air temperature and the ambient temperature, and determine whether the air conditioning system has an abnormal return air condition based on the first difference. When the return air of the air conditioning system is determined to be abnormal, a second difference between the return air temperature and the duct temperature is calculated, and the air conditioning system is judged to be short-circuited based on the second difference. The air conditioning system includes a cooling mode and a heating mode. When the air conditioning system is in cooling mode, it determines whether the air conditioning system has an abnormal return air condition based on the first difference, including: Determine whether the first difference is less than the first threshold temperature difference; If so, the air return air of the air conditioning system is determined to be abnormal; When the air conditioning system is in cooling mode, determining whether the air conditioning system has a return air short circuit based on the second difference includes: Determine whether the second difference is less than the second threshold temperature difference; If so, the air conditioning system is determined to be short-circuited in the return air circuit. When the air conditioning system is in cooling mode, determining whether the air conditioning system has a return air short circuit based on the second difference also includes: Detect the operating position of the indoor unit of the air conditioning system; The second threshold temperature difference is compensated according to the operating setting, and the air conditioning system is judged to have a return air short circuit based on the compensated second threshold temperature difference.

2. The method for detecting short circuits in the return air of an air conditioning system according to claim 1, characterized in that, When the air conditioning system is in heating mode, determining whether the air conditioning system has an abnormal return air condition based on the first difference includes: Determine whether the first difference is greater than the third threshold temperature difference; If so, the air return air of the air conditioning system is determined to be abnormal.

3. The method for detecting short circuits in the return air of an air conditioning system according to claim 2, characterized in that, When the air conditioning system is in heating mode, determining whether the air conditioning system has a return air short circuit based on the second difference includes: Determine whether the second difference is greater than the fourth threshold temperature difference; If so, the air conditioning system is determined to be short-circuited in return air.

4. The method for detecting short circuits in the return air of an air conditioning system according to claim 1, characterized in that, The first threshold temperature difference ranges from -5℃ to 0℃; The second threshold temperature difference ranges from -4℃ to 4℃.

5. The method for detecting short circuits in the return air of an air conditioning system according to claim 3, characterized in that, The value range of the third threshold temperature difference is 0℃~10℃; The fourth threshold temperature difference ranges from -2℃ to 0℃.

6. The method for detecting short circuits in the return air of an air conditioning system according to claim 3, characterized in that, When the air conditioning system is in heating mode, determining whether the air conditioning system has a return air short circuit based on the second difference also includes: Detect the operating position of the indoor unit of the air conditioning system; The fourth threshold temperature difference is compensated according to the operating setting, and the return air short circuit of the air conditioning system is determined based on the compensated fourth threshold temperature difference.

7. The method for detecting short circuits in the return air of an air conditioning system according to claim 1, characterized in that, The indoor unit of the air conditioning system has four operating settings, and when the indoor unit is operating at the first setting, the compensation value for compensating the second threshold temperature difference is the first compensation value. When the indoor unit of the air conditioner is working at the second setting, the compensation value for compensating the second threshold temperature difference is the second compensation value. When the indoor unit of the air conditioner is working at the third setting, the compensation value for compensating the second threshold temperature difference is the third compensation value. When the indoor unit of the air conditioner is operating at the fourth setting, the compensation value for compensating the second threshold temperature difference is the fourth compensation value.

8. The method for detecting short circuits in the return air of an air conditioning system according to claim 6, characterized in that, The indoor unit of the air conditioning system has four operating settings, and when the indoor unit is operating at the first setting, the compensation value for compensating the fourth threshold temperature difference is the fifth compensation value. When the indoor unit of the air conditioner is working at the second setting, the compensation value for compensating the fourth threshold temperature difference is the sixth compensation value. When the indoor unit of the air conditioner is working at the third setting, the compensation value for compensating the fourth threshold temperature difference is the seventh compensation value. When the indoor unit of the air conditioner is operating at the fourth setting, the compensation value for compensating the fourth threshold temperature difference is the eighth compensation value.

9. The method for detecting short circuits in the return air of an air conditioning system according to claim 7, characterized in that, The first compensation value is 0, and the values ​​of the second, third, and fourth compensation values ​​are all within the range of 0 to 5°C. The second compensation value is less than the third compensation value, and the third compensation value is less than the fourth compensation value.

10. The method for detecting short circuits in the return air of an air conditioning system according to claim 8, characterized in that, The fifth compensation value is 0, and the values ​​of the sixth, seventh, and eighth compensation values ​​are in the range of -5 to 0℃, with the sixth compensation value being greater than the seventh compensation value and the seventh compensation value being greater than the eighth compensation value.

11. The method for detecting short circuits in the return air of an air conditioning system according to claim 1, characterized in that, When the air conditioning system is equipped with an outlet air temperature sensor, the air conditioning system return air short-circuit detection method further includes the following when the return air of the air conditioning system is determined to be abnormal: Detect the outlet air temperature of the air conditioning system; The return air short-circuit ratio of the air conditioning system is calculated based on the outlet air temperature, the return air temperature, and the ambient temperature. The return air status of the air conditioning system is determined based on the return air short-circuit ratio.

12. The method for detecting short circuits in the return air of an air conditioning system according to claim 11, characterized in that, The calculation model for the return air short-circuit ratio is as follows: Ф= (T 回风 - T 环境 ) / (T 出风 - T 环境 ) Where Ф is the return air short-circuit ratio, and T 回风 The return air temperature, T 出风 T represents the outlet air temperature. 环境 The ambient temperature is [value missing].

13. The method for detecting short circuits in the return air of an air conditioning system according to claim 11, characterized in that, When the air conditioning system is in cooling mode, the return air status of the air conditioning system is determined based on the return air short-circuit ratio, including: The return air short-circuit ratio is compared with a first preset ratio and a second preset ratio, and the preset range in which the return air short-circuit ratio falls is determined. When the return air short-circuit ratio is within the first preset range, the air return of the air conditioning system is determined to be normal. When the return air short-circuit ratio is within the second preset range, it is determined that the air conditioning system has a return air short circuit. When the return air short-circuit ratio is in the third preset range, the air conditioning system is determined to be faulty.

14. The method for detecting short circuits in the return air of an air conditioning system according to claim 11, characterized in that, When the air conditioning system is in heating mode, the return air status of the air conditioning system is determined based on the return air short-circuit ratio, including: The return air short-circuit ratio is compared with a third preset ratio and a fourth preset ratio, and the preset range in which the return air short-circuit ratio falls is determined. When the return air short-circuit ratio is within the fourth preset range, the return air of the air conditioning system is determined to be normal. When the return air short-circuit ratio is in the fifth preset range, it is determined that the air conditioning system has a return air short circuit; When the return air short-circuit ratio is in the sixth preset range, the air conditioning system is determined to be faulty.

15. The method for detecting short circuits in the return air of an air conditioning system according to claim 13, characterized in that, The first preset ratio ranges from 10% to 40%, and the second preset ratio ranges from 40% to 70%. The first preset interval is 0~Φ1, the second preset interval is Φ1~Φ2, and the third preset interval is Φ2~1; Wherein, Φ1 is the first preset ratio and Φ2 is the second preset ratio.

16. The method for detecting short circuits in the return air of an air conditioning system according to claim 14, characterized in that, The third preset ratio ranges from 10% to 40%, and the fourth preset ratio ranges from 40% to 70%. The fourth preset interval is 0~Φ3, the fifth preset interval is Φ3~Φ4, and the sixth preset interval is Φ3~1; Wherein, Φ3 is the third preset ratio and Φ4 is the fourth preset ratio.

17. An air conditioning system return air short-circuit detection device employing the air conditioning system return air short-circuit detection method as described in any one of claims 1 to 16, characterized in that, include: Return air temperature sensor for detecting return air temperature, wired controller temperature sensor for detecting ambient temperature, pipe temperature sensor for detecting pipe temperature, and outlet air temperature sensor for detecting outlet air temperature. The air conditioning system return air short circuit detection device determines whether the air conditioning system has an abnormal return air by calculating the temperature difference between the return air temperature sensor and the wired controller temperature sensor. The system determines whether the air conditioning system has a return air short circuit by calculating the temperature difference between the return air temperature sensor and the pipe temperature sensor.

18. An air conditioning system, characterized in that, The air conditioning system has the air conditioning system return air short circuit detection device as described in claim 17.

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