DIAGNOSIS A foreign object is likely interfering with the condenser fan blades, or the fan motor bearings are failing.
FIX Unplug the unit. Access the rear panel. Visually inspect the fan area for any obstruction—plastic packaging material or ice chips are common. Carefully remove any debris. Manually spin the fan blades to check for smooth rotation.
IF THAT DIDN'T WORK The fan motor shaft may be misaligned. Check that the fan is securely mounted to the motor shaft. If the grinding persists after clearing debris, the fan motor assembly likely needs replacement.
HEADS UP Do not operate the unit with a grinding fan. It can overheat the compressor and cause permanent failure. Always disconnect power before inspecting internal components.