Haier Air Conditioner Repair Summary: Inverter Console Air Conditioner, shows fault code E5 upon startup.
Model: KFR-50/60LW/U(DBPZXF)
Fault Phenomenon: Alarm E5 upon startup
Repair Process: According to the alarm feedback indicating AC overcurrent fault, the analysis points to a short circuit in the CT coil, power module failure or poor heat dissipation of the outdoor unit. During on-site testing, sometimes it alarms upon startup and sometimes it runs but fails to reach the highest frequency after about 5 minutes and then alarms. After replacing the SPDU module, some machines can run normally, but others still alarm. Upon inspection, it was found that thermal grease on some modules was unevenly applied (uneven application of thermal grease reduces the contact area between the module's heat dissipation surface and the heat sink), leading to poor heat dissipation of the module. After reapplying the thermal grease, the test run was normal. However, some machines still alarmed. Further inspection revealed that the condenser of the outdoor unit and the heat sink of the SPDU module were overheating, but there seemed to be no problem with the speed of the external fan (the installation environment of the outdoor unit is good). Trying to replace the outdoor motor resulted in a normal test run.
Repair Measures: Based on the detected faults, replace the module or the outdoor motor, restoring the air conditioner to normal operation. Beijing Haier Air Conditioner Repair.
Note: Some thermally conductive silicon grease purchased from the market has inferior quality and should not be used to avoid misjudgment of faults.
Beijing Haier Air Conditioner Repair Center, August 10, 2011.