Furnace vibrates excessively or rattles during operation.

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

Steps to check:

• Tighten fasteners: Inspect the blower housing, control board mounting, and cabinet panels. Tighten any loose screws.
• Check blower wheel balance: Remove the blower assembly and inspect the wheel for bent fins or accumulated debris on one side. Clean thoroughly. Replace the wheel if damaged.
• Isolate piping: Ensure gas flex line and PVC vent pipes are not resting against the furnace cabinet. Use pipe hangers or insulation to prevent contact.
• Level the furnace: Use shims to level the furnace on its platform or slab to reduce vibration transfer.

If vibration persists, a technician can further evaluate motor mounts and duct connections.