Trane air conditioner indoor unit is very noisy with a rattling or buzzing sound when the blower runs.

Safety first: Turn off power before tightening or adjusting any components.

• Tighten panels: Secure all access doors and panels with screws. Add foam tape if panels vibrate.
• Secure blower: Check that the blower assembly mounting bolts are tight.
• Isolate lines: Ensure refrigerant lines are not touching the cabinet or other metal surfaces; add foam insulation or clamps as needed.

If noise persists, a technician can further isolate and secure internal components.