Unit cools but makes loud rattling or vibrating noises during operation.

Safety first: Turn off and unplug the unit before touching moving parts.

• 1. Check installation: Ensure the unit is on a stable, level surface. For window units, verify the mounting kit is tight and the chassis is not rattling against the window frame.
• 2. Inspect fan area: Remove the front grille and look for foreign objects (plastic, leaves, etc.) in the blower wheel. Remove any debris.
• 3. Tighten screws: With panels removed, gently check and tighten screws securing the fan housing, compressor mounts, and metal panels.
• 4. Check fan blades: Spin the blower wheel and condenser fan by hand. If they wobble or scrape, the hub may be cracked or the shaft bent. Replace the fan or blower wheel if damaged.
• 5. Motor bearings: If noise is a grinding or squealing sound that changes with fan speed, the fan motor bearings may be worn and the motor should be replaced.