Safety: Turn off power at the disconnect before inspecting moving parts.

Inspect fan blade: Remove top grille and check that the fan blade is tight on the motor shaft. Tighten set screw if loose.
Check for debris: Remove sticks, leaves, or other objects from the fan and base pan.
Examine blade alignment: Spin the blade by hand and watch for contact with the shroud. Gently straighten bent blades or replace the fan blade if severely damaged.
Compressor mounts: Verify compressor mounting bolts and rubber isolators are intact and tight.

Loud banging or rattling noise from outdoor Fraser‑Johnston condenser

Possible Causes