Cause analysis: The air conditioner has been installed for more than a year, used in a restaurant, with a power supply of 220 volts. The user reported that after working for some time, the air conditioner would intermittently cool and then stop cooling, failing to work properly. Upon inspection, the pressure was found to be 5Kg and the current was 12.5A. It was suspected that the condenser was too dirty. After cleaning the condenser, the fault was not resolved. Observing the outdoor unit, it was found that when the air conditioner was operating, the external fan motor speed was slow. After 30 minutes of operation, the external fan stopped, and the compressor current increased causing it to shut down. At this point, an inspection revealed an open circuit in the fan motor winding, and the motor casing was very hot. After the motor cooled down, the winding resistance was measured as normal, leading to the conclusion that the fan capacitor was faulty.
Midea Air Conditioner: Frequent shutdowns, poor cooling effect.
Fault symptoms: Frequent shutdowns, poor effect.
Maintenance measures: Replace the fan and capacitor, test machine operation is normal.
Experience summary: Based on the detection, it can be determined that due to the failure of the fan capacitor, the fan protection mechanism activates, causing the fan to stop rotating. This leads to poor system heat dissipation, which in turn causes the compressor to overheat and shut down. Three minutes later, the compressor restarts, repeating the cycle, resulting in frequent start-stop operations. From this fault, it can be seen that some faults are caused by multiple factors, which are the result of interactions between electrical control and the system. Therefore, during maintenance, careful and detailed inspections and observations should be carried out to avoid unnecessary detours.
Reposted from: Beijing Midea Air Conditioning Repair Center http://blog.163.com/mideaktiao_2012/.