Mitsubishi inverter air conditioner repair case

Frequency Conversion Machine Maintenance Case I. R Frequency Conversion Fault Number: 020101
Machine Model: KFR-35GW/BPY-R
Symptoms: External machine noise causes analysis: After the maintenance personnel come to the door, the air conditioner detects, when the air conditioner starts, everything is normal. When the temperature difference between the set temperature and the indoor temperature is large, the compressor is in the high frequency operation, the current of the external machine starts. Increased and jittering. It was found that the outdoor unit's copper tube touched the shell, and after being adjusted and turned on, the vibration sound was reduced, but the sound of the frequency rise was emitted when the press was operating.
Remedy: Explain to the user that the sound raised by the frequency converter is a normal sound.
Experience summary: When the frequency converter operates at a high frequency, a large current is emitted, which is difficult to avoid. It should be explained to the user that the upswing time is short.
No.: 020102
Machine Model: KFR-35GW/BPY-R
Fault phenomenon: After the power is turned on, the whole machine does not start up, and the display shows the E1 code.
Analysis of the reasons: check the power supply connection is normal, check the fault code for internal machine communication failure, use a multimeter to check the internal motherboard to the external machine power supply is normal, there are also S side of the excitation signal, indicating that the internal and external machine communication is not a failure, consider The reason for the failure of the general frequency conversion machine is that there are many factors in the outdoor unit. Open the outer case and find that the capacitor on the external power supply board has obvious cracking phenomenon. The reason for further analysis of the capacitor burst may be the failure of the rectifier bridge. Use a multimeter to check the rectification. The bridge's positive and negative resistance is zero, and the rectifier bridge is short-circuited. At the same time replace the outdoor power supply board and rectifier bridge, the boot test machine is normal.
Solution: Replacement of outdoor power supply board and rectifier bridge. Summary of experiences: There are many causes of E1 fault. The fault code only represents a range. The cause of inverter capacitor explosion is generally the capacitor itself and rectifier bridge fault.
No.: 020103
Machine Model: KFR-35GW/BPY-R
Fault phenomenon: Start the indoor unit work, the outdoor fan work, the compressor does not start, the display shows no fault code.
Treatment process: According to the fault phenomenon, it should be a bad compressor or an outdoor electric control board problem. Check the user's power supply, the voltage fluctuates around 220V and should be normal. Turn on the outdoor unit and measure the DC voltage of the main control board in the outdoor room at 310V. If the voltage of the 5V module is measured again, there is no output and the module is judged as bad.
Solution: Replacement of the frequency conversion module Experience summary: It is not very important whether the fault code has or is not displayed. It is important to check and analyze each component patiently.
No.: 020104
Machine Model: KFR-35GW/BPY-R
Symptoms: P0 (module protection) protection after power-on analysis: According to the fault code, it is judged that the inverter module of the outdoor unit is bad. After the frequency conversion module of the measurement outdoor unit is normal, the main board is working properly. After careful inspection of the user voltage fluctuations, but the voltage fluctuations should show "P1" protection, after the test machine for an hour and found that the user's instantaneous voltage fluctuations are too large, causing module protection, it is recommended that users install the regulator, the test machine is normal .
Solution: It is recommended that users install the regulator experience summary: Before the maintenance, carefully check the user's power supply voltage (load voltage, measured voltage after the compressor is working).
No.: 020105
Machine Model: KFR-35GW/BPY-R
Symptom: The outdoor unit does not start and E1 is displayed.
Analysis of the cause: After the start-up running test S, N has a DC signal, it is determined as an outdoor unit failure, check the outdoor unit power board has indicator light, there is a 310V voltage output, the module output +5V is normal, the last inspection of the internal and external machine connection line was found to have previously lengthened Through pipelines, poor contact at the extension line leads to signal interference between S, N, and L, causing the outdoor unit not to operate.
Solution: Replace the internal and external cables. Summary of Experience: When all components are checked and there is no obvious fault, be sure to check if there is any problem with the connecting line. Bad wiring often affects the frequency conversion signal.
No.: 020106
Machine Model: KFR-35GW/BPY-R
Symptom: The fault code “E1” is displayed and “E1” is displayed after two minutes of turning on the KFR-35GW/BPY-R. Then the air conditioner does not work. The air conditioner was purchased in July 2003 and used for 1 month. When the door is checked, the LED on the power board of the outdoor unit is extinguished, which indicates that the power supply of the outdoor machine control unit is not working properly. It is estimated that the outdoor unit is faulty. Check the 220V voltage on the outdoor machine terminal block, the DC voltage at the filter capacitor of the power supply board is not available, the voltage of the AC 220V from the power supply board to the rectifier bridge is normal, and the open circuit of the rectifier bridge is measured, causing the switching power supply circuit on the power supply board and module to work abnormally. The outdoor CPU has no operating voltage, which causes indoor and outdoor communication faults.
Solution: After the rectifier bridge is replaced, the whole machine works normally and the fault is eliminated.
No.: 020106
Machine Model: KFR-35GW/BPY-R
Fault phenomenon: Power on, indoor unit work stop, E1 protection.
Analysis of the reasons: The power supply voltage and signal voltage of the outdoor power meter are normal. There is a 300V DC voltage between the PNs. U, V, and W have no AC voltage output. The power-off detection P and U, V, and W terminals have zero resistance. Therefore, it is judged that the frequency conversion module is faulty, and the replacement module test machine works normally for 30 minutes, and the user is satisfied.
Remedy: Replace the inverter module.
Experience summary: Theoretic analysis is that the indoor boot is stopped, it is indoor and outdoor communication is not on the test, the outdoor power supply voltage and signal voltage are normal, then eliminate the indoor unit problem; PN terminal has 300V DC voltage, indicating that there is no problem with the outdoor power supply, with a multimeter The measurement module (in both cases of power-on and power-off) is abnormal. There is no voltage output from the module, and there is no low-voltage power supply outside the room, causing internal and external devices to fail to communicate, so the replacement module is normal.
Number: 020107
Machine Model: KFR-35GW/BPY-R
Symptom: E1 protection is displayed and the system cannot be turned on.
Analysis of reasons: The user reported that the previous work was normal, the power-on test machine immediately displayed E1, check the internal and external machine connection is no exception, try to change the internal machine and external machine motherboard failure remains, then carefully ask the user before and after the failure situation, the user has an electrician The fault occurred after overhaul of the corridor circuit. Since the machine outlet was not grounded, there was a doubt about the replacement of the zero line fire line. The fire line and neutral line of the air-conditioning socket were tried and replaced, and the fault was eliminated.
Remedy: Summarize the experience of adjusting the L and N lines in the socket: In the course of maintenance, the user should be informed of the situation before and after the fault in order to determine the fault range and avoid detours.
Number: 020108
Machine Type: KFR-26(35)GW/BPY-R KFR-35GW/BPY-R
Symptom: When the cooling and heating display shows that the temperature differs from the actual room temperature by more than 5 degrees. Cause Analysis: This type of problem is generally a room temperature sensor problem. The actual temperature in the vicinity of the sensor is basically the same as the display temperature, but it is different from the room temperature. , It is a few degrees higher, and it is determined that the sampling position of the room temperature sensor is unreasonable at the time of design, (the factory takes the side of the indoor fan motor).
Solution: The problem is solved by changing the position of the room temperature sensor to the return air of the evaporator.
Experience summary: After careful observation, the problem is small, but it must also be handled properly. At the same time, both cooling and heating must be taken into consideration.
No.: 020109
Machine Model: KFR-35GW/BPY-R
Symptom: E1 is displayed after half an hour of power on.
Analysis of the reasons: After inspection, it was found that half an hour after normal operation of the aircraft, it heard two “squeaks” and suddenly stopped. The fault was displayed as indoor and outdoor communication was not smooth. Before shutdown, the current is 6A, the voltage is 210V, the fluorine pressure is 4kgf/cm, the current and voltage values ​​are low, but the air conditioner should be used normally. After shutting down for 5 minutes, it can be normally turned on again. The initial judgment is that it belongs to the outdoor circuit fault. After checking, the outdoor unit module can not provide +5V and +12V power for the outdoor unit power board after checking for a period of time. After replacing the outdoor unit module, the air conditioner After working for a period of time, no indoor or outdoor communication problems were found. However, the high exhaust temperature protection of the compressor appeared. After the system was filled with Freon, the machine was operating normally.
Solution: Replace the module and add some fluorine.
Experience summary: The DC power supply of the inverter outdoor unit power supply board is fed back by the inverter module. If no power indicator is found on the power board, it is often mistakenly judged as a failure of the outdoor power board. In this case, pay attention to whether the module can To provide +5V, +12V, when there is communication failure in the inverter, there may be several faults.
No.: 020110
Machine Model: KFR-26GW/BPY-R
Symptoms: After a period of time, the machine stops and E1 protection occurs.
Analysis: E1 is a communication failure. After checking the sinusoidal DC voltage signal between S and N, it is determined that the internal control system should be no problem. The outdoor unit power supply board has an indicator lamp, the module input voltage is 310V, and the output +5V is normal. Compressors and modules have normal resistance. All components are inspected properly. Suspected line problems. After careful inspection, it is found that the module interface is inserted loosely. After plugging in, the test machine is normal. Seal the interface with glass glue to prevent loosening. .
Remedy: Insert the plug and seal the connector with glass sealant.
Experience summary: For such failures, when checking the electrical components are normal, you should carefully check each component and interface for good contact.
No.: 020111
Machine Model: KFR-26GW/BPY-R
Fault phenomenon: “P2” protection shutdown cause analysis: protection shutdown occurs during work, machine use environment is good, “P2” is compressor overheat protection, and the possibility of compressor overheat protection due to poor cooling can be excluded; 20 minutes after the operation of the machine is observed Stop protection, measured the thermal protection device on the exhaust pipe of the compressor, then short-circuit the thermal protector test machine, the machine is normal, and it is determined that the compressor exhaust pipe thermal protector malfunctions.
Solution: Replace the compressor exhaust temperature sensor and the machine will return to normal.
Lessons learned: We should carefully check whether the various protection functions operate when the machine fails.
No.: 020112
Product Model: KFR-26GW/BPY-R
Symptoms: E1 appears within 3 minutes of internal operation
Process: power test machine, the internal machine is operating normally. When the internal machine is working for 3 minutes, the whole machine is protected and shut down, the remote control cannot be turned on, and the internal machine has a communication failure. According to the failure time, it is concluded that the fault should appear on the external machine. Because the KFR-26GW/BPY-R external main control board and the power board are integrated together, it is meticulously checked that the frequency conversion module has no +5V and +12V output, so it is determined that the frequency conversion module is bad.
Solution: Replacement of the frequency conversion module Experience summary: Analyze the conclusions from the measurement data, faster and more accurately.
No.: 020113
Machine Model: KFR-26GW/BPY-R
Symptom: The display temperature is not consistent with the set temperature during shutdown (a difference of 4°C)
Analysis of the reasons: According to the situation reflected by the user, the detection situation is: the power supply is normal (218V). Working pressure (in cooling): 0.4 MPa. The electronic control function is normal and the remote control operates completely. Outlet temperature is 47°C. Judging the machine itself does not have any problems. However, there is indeed a deviation between the temperature displayed by the air-conditioning indoor unit and the set temperature at the time of shutdown (the maximum difference is 4°C), which is inconsistent with the propaganda of the aircraft (the indoor temperature difference is +0.5°C). Through patience and user communication, explanation, user satisfaction.
Solution: Explain the instructions to the user.
Experience summary: When a network encounters such problems, it should be patient and meticulous to communicate with users. The key is to understand the purpose that users want to achieve and to maximize user satisfaction.

IJOY Vape

IJOY Vape,IJOY E-Cigarette,IJOY Disposable Vape,IJOY Vape Kit,IJOY Vape Pod

TSVAPE Wholesale/OEM/ODM , https://www.tsecigarette.com