Central air conditioners have a lot of moving parts working to keep your home cool and comfortable. Over time, the parts will wear out and lead to a variety of sounds you may not have heard before. Some of these sounds can be easy to identify and fix, like a loose panel cover, or could be a sign of a bigger problem like a worn out condenser motor.
Air Conditioner Rattling Sounds
Rattling sounds are a fairly common with air conditioners. Over time the various fasteners attaching components to the unit can become loose. If you hear a rattling sound, check the screws or bolts on the cover plates. If the rattling noises is still heard after tightening the panels, remove the cover and check inside the unit for the loose panels. After listening for rattles, always turn the power to the unit off at the breaker.
Central AC Whistling Sounds
Whistling sounds are usually a result of faulty seals. Check for cracks and gaps in the seams of ducts near the AC unit and in the duct work that carries the air throughout the home. Examine the seams around these areas for loose connections and re-tighten any loose screws or bolts. If tape was used to cover the seals, make sure the tape is adhering well to the duct seams.
Like a car, an air conditioner motor uses belts to turn a fan. Over time the belt can stretch and wear out. If there is periodic screeching that only occurs when the unit turns on to blow air or cool the air down, it is likely a worn-out belt that needs to be replaced. A qualified HVAC technician should check the belt and replace it if needed.
Clunking sounds can mean a part has come loose inside the AC unit. A loose fan blade on a motor will often make sounds as it turns. It may also be that a plastic component or cover plate is coming into contact with the fan. A qualified HVAC technician should inspect the unit to ensure it is operating safely.