Furnace vibrates excessively and causes rattling noises in ducts

Safety: Turn off power before tightening or adjusting components.

• Tighten hardware: Check all accessible screws on blower housing, burner door, and flue supports. Tighten any loose fasteners.
• Inspect blower wheel: Look for bent fins or heavy dust buildup on one side. Clean the wheel evenly to restore balance.
• Support ductwork: Ensure flexible ducts are properly supported and not resting on structures that amplify vibration.
• Test operation: Restore power and observe. Persistent severe vibration may require blower or combustion fan replacement.