A, central air conditioning maintenance method
1, the whole machine automatically stops when working.
Fault: According to the user's feedback, the central air conditioner usually stops automatically during use, but it can be restarted as soon as it is turned on. Good refrigeration effect during operation and irregular shutdown. On-site inspection shows that the power supply voltage is normal with a multimeter, and the voltage of each pole of the motherboard is normal when working. If the motherboard is replaced repeatedly, it will occasionally fail, indicating that the original motherboard is normal and the voltmeter has been connected to the port of the internal machine for repeated debugging. It was found that the voltmeter reading suddenly dropped as soon as the air conditioner stopped, and it immediately returned to normal. If you suspect that the power supply is in poor contact, move the plug by hand, and the reading of the voltmeter will swing. When the power socket was disassembled, it was found that the screw for fastening the neutral terminal was not tightened, which caused serious ignition. After replacing the new socket, test the machine repeatedly, and the fault disappears.
Maintenance summary: this kind of fault looks complicated on the surface, but it is often caused by external reasons, so basic maintenance methods should be used when repairing and handling the fault.
2. The compressor starts frequently.
Troubleshooting: During the use of this machine, it is found that the refrigeration effect is poor and the outdoor compressor is noisy. The working voltage is tested at home, and the voltage is 223V after the compressor is started. At this time, the cooling effect is ok. After about 10 minutes, the noise of the outdoor compressor increases. After 7-8 minutes, the compressor stops and the internal compressor only supplies gas. After about 5 minutes, the compressor is restarted. Check the working environment of the external compressor and the condensation on the condenser surface. It is suspected that poor heat dissipation caused the press to stop. After cleaning the condenser of the external machine, the trial operation failures are still frequent. When the outer casing is opened, I feel that the press is particularly frozen. Check whether all lines are in good condition. Connect the pressure gauge and clamp ammeter and start the machine. The pressure is 7Kgf/cm2 and the current is 8.7A, indicating that the pressure is too high to protect the press. Careful observation shows that the speed of the external fan motor is much slower than before. After replacing the external fan capacitor, the speed of the debugging fan is increased, the working pressure is reduced to 4.8Kgf/cm2, and the working current is also reduced to 6A. The air conditioner is running normally, and there is no frequent start and stop.
3. Indoor noise.
Indoor noise refers to the harsh noise after starting. First of all, check the power supply voltage of the indoor fan, which is100V when it is turned off. After closing, the indoor unit is still running slowly. This is because the plastic motor frame is deformed after being heated by the indoor motor, which leads to the displacement of the plastic motor. The unpleasant noise is caused by the collision between the fan blades and the chassis, accompanied by the smell of burning. Therefore, it can be judged that the fan control thyristor is damaged, and the maintenance method is to suggest replacing the main control board.
4. Indoor noise.
Indoor noise refers to the harsh noise after starting. First of all, check the power supply voltage of the indoor fan, which is100V when it is turned off. After closing, the indoor unit is still running slowly. This is because the plastic motor frame is deformed after being heated by the indoor motor, which leads to the displacement of the plastic motor. The unpleasant noise is caused by the collision between the fan blades and the chassis, accompanied by the smell of burning. Therefore, it can be judged that the fan control thyristor is damaged, and the maintenance method is to suggest replacing the main control board.
The above example is about the knowledge and methods of central air conditioning maintenance, from which we can find that there are many common problems and faults in central air conditioning, such as poor cooling and heating effect. At this time, it needs to be handled through disassembly and professional experience judgment. When necessary, Bian Xiao also suggested that you can use professional tools to repair it, hoping to achieve satisfactory results and conditions as expected. Of course, if most consumers are considered inexperienced, Bian Xiao thinks the best way is to turn to professional maintenance agencies. I hope this will minimize the loss as much as possible.