Furnace rattles, vibrates, or makes banging noises when starting or stopping.

Safety first: Turn off power before tightening internal components.

• Tighten panels: Ensure all furnace access panels are properly seated and screws are tight.
• Secure blower assembly: Check mounting bolts for the blower housing and tighten as needed.
• Inspect duct connections: Look for loose or unsupported ducts near the furnace. Add hangers or braces where necessary.
• Add padding: For oil-canning sheet metal, carefully add foam tape or braces to reduce flexing, without blocking airflow.