What Causes Air Conditioning to Be Noisy?

Dirt

• If an air conditioner gets to be too dirty, the accumulated debris and lint can create noise as air blows through it. This can sound like buzzing, clanking or a clicking sound as air flow is blocked or reduced. Disconnect power to the air conditioner and use a clean, damp cloth to clean the air vents and grilles. If they're excessively dirty, use a vacuum cleaner to suction out dirt and debris.

Outdoor Debris

• If the air conditioner is a whole-home model, look at the main unit located outdoors and clear away any leaves, dirt, grass or debris that may have blown up against the unit and may be causing it to rattle or make noise. It may sound like something hitting the air conditioner repeatedly or it might be more quiet, like a clicking or squeaking. If you can, remove anything that may be caught in the air conditioner and clear a path around the unit to prevent items from getting caught later.

Filter

• A dirty air filter can reduce the effectiveness and cooling power of the air conditioner and may make it run more frequently, but it can also cause a noise. If the air conditioner is humming or buzzing, the filter may be dirty and needs to be cleaned. Once the air conditioner has been disconnected from power, open the access panel and remove the air filter. Clean it with soapy water if it is a permanent filter, and rinse it out before air-drying for at least 24 hours. Replace a disposable air filter. Note that if the filter is positioned poorly, this can also create a squeaking noise as air leaks around the filter.

Condenser Coils and Fan

• If the condenser coils are dirty, the air conditioner can make a buzzing or ticking sound. Open the air conditioner and clean out the condenser coils with a vacuum cleaner brush attachment to remove any dirt that may be creating problems with the coils. If the fan needs to be cleaned, it may be making a squeaking sound during operation. Use a soft brush to clean the fan blades. Look for signs that the fan is hitting the sides of the air conditioner and creating noise, a problem which may require a technician's help.

Location

• Ensure that the air conditioner is not located too close to the side of a building or wall, as the normal vibration of the unit can create noise if the air conditioner is coming in contact with another surface when it is turned on. Allow a space around the perimeter of the air conditioner to reduce vibration. Check the ducts for loose hardware.