4 Tips for Quieting Your A/C

It’s normal for your air conditioner to make noise when it’s operating, but unusual or loud sounds can be worrisome. If you’re hearing high-pitched squealing, shrill shrieking, loud banging or steady hissing sounds, there may be something seriously wrong, so call your HVAC contractor for a diagnosis right away.

Other noises are just annoying, though, and quieting your A/C may not require expertise. Here are some helpful tips for solving common, irritating air conditioner sounds:

Silence a Rattling Blower Fan

Loose, dirty or bent fan blades can cause rattling or murmuring noises in the blower unit. To quiet the sound, vacuum up any collected debris inside the blower compartment and dust off the fan blades. Use a screwdriver or Allen wrench to tighten up the central hub if the fan is loose. For a bent blade, use your hands and apply steady pressure to realign it.

Lubricate a Noisy Fan Motor

If your blower unit has oil ports, you can lubricate the fan motor to quiet humming or grinding noises – just put a couple of drops of an “SAE 10” oil to each port. To keep it well lubricated, add more oil at the start of each cooling season.

Tighten Rattling Screws

The various mechanical parts located inside the air handler and condenser cabinets vibrate a bit whenever they’re running. This minor repeated movement can gradually loosen some of the cabinet and mounting screws and cause an irritating rattling sound. To fix this, listen closely for the rattle and follow it back to its source, then fully tighten any loose screws.

Quiet Compressor Clamor

Normal A/C compressor noise can get quite loud when it bounces off a home’s exterior walls. If the racket from your compressor is ruining your outdoor enjoyment, talk to your HVAC pro about installing vibration-lessening mounts or a noise-insulating compressor blanket.