Indoor unit makes loud rattling or buzzing noises during operation

Safety: Turn off power before removing covers.

• Check front panel and filters: Ensure the front panel is fully latched and filters are properly seated.
• Tighten screws: Remove the front cover and gently tighten visible screws securing the fan housing and PCB bracket.
• Inspect blower wheel: Look for heavy dust buildup or foreign objects in the blower. Clean carefully with a brush and vacuum.
• Secure piping: If copper pipes are touching the plastic casing, insert foam or rubber spacers to prevent vibration noise.
• Test: Restore power and run the unit. If noise persists, the blower wheel may be cracked or the motor bearings worn and should be replaced.