Save $200+ This Summer: Learn to Repair Your Own Air Conditioner

4. Strange Smells or Noises?

This is often caused by buildup or debris inside the system:

Clean the Filters and Inner Components: Musty smells are usually a sign of mold or mildew on filters or coils. Take out the filters, clean them, and use a soft cloth to wipe around the coil area. For stubborn smells, a mild solution of water and white vinegar can help.
Remove Visible Debris: Rattling or buzzing sounds might mean leaves, twigs, or dust have made their way into the outdoor unit. Turn off the power, then gently clean around the fan and vents.
Tighten Loose Screws: If the sound seems to come from vibration, check for any loose screws or panels and tighten them using a screwdriver.