Whether you have a window unit or built-in ducts, air conditioning is a necessity in warm climates. Over time, however, they can develop a familiar rattle that doesn’t seem to go away. Turning off the air can be a punishment, however. That irritating squeak might seem like a small price to pay for the cooling benefit of air conditioning. Fortunately, professionals say most noises don’t require major intervention. Instead, look for minor gaps and routine maintenance to fix some of the most common causes of air conditioner noise.
1. Pay attention to the gap
A major contributor to squeaky AC noise is gaps on the sides of a window unit. “Almost every manufacturer offers a slider to fill the gap, which doesn’t always do the job. The foam insulation on the sides deadens noise much better and helps keep cool air inside,” said Mark Snell, owner and founder of Polestar Plumbing, Heating & Air Conditioning in Kansas.
Rattles and clicks can also result from the vibration of a window unit against the window frame. If there is a gap between the base of the air conditioner and the window frame on the outside of the house, you may need to consider that gap as well. Support the weight of the unit with mounting brackets, concrete slabs, or mounting rails. These securing mechanisms help the air conditioner stay upright and not tip over.
2. Isolate or replace
“Ensure the seal around the window unit and window frame is in good condition and provides insulation. Good insulation requires the unit to run for shorter periods of time to cool the room; Holes and gaps allow flowing air to increase unwanted noise levels,” advises Steve Stewart, owner of Southern Comfort Mechanical in Texas.
Insulate the outside edge of the air conditioner with foam strips. If the problem persists, the culprit could be the window itself. If your windows haven’t been replaced in decades, chances are the panes will vibrate or the window frame will splinter. If the insulation isn’t working, call in a window expert to see if it’s economical to completely replace the windows.
3. Get a sound blanket
Another way to quiet a noisy air conditioner is with a sound blanket. “You can also have your contractor install a soundproof blanket around your air conditioning compressor. A soundproof blanket is a great way to significantly reduce the noise level of your air conditioner without sacrificing its efficiency,” says Snell.
If you live in a central air home, your heating, ventilating, and air conditioning (HVAC) system includes a large compressor and condenser outside the home. The hum can disturb people sleeping or working in adjacent rooms. An HVAC technician can install a sound blanket or an air conditioning fence. You should have this done by a professional so that the distance is correct and the device does not overheat. These blankets can also reduce the amount of dirt and dust entering the unit, helping to extend the life of the machine.
4. Keep it clean
It’s amazing how much dust and dirt can accumulate in air conditioning systems. The particles can accumulate, making for a noisy — and allergen-filled — home. For central air units, periodically have a qualified professional come out to clean dust in the vents and in the compressor unit. Replace the filters regularly and patch any leaks in the duct system.
“Keep the filter screens clean by removing and washing them to allow the desired airflow; the same goes for the external coils. The gaps between the ribs should be free of debris build-up. Follow the instruction manual to lift them and place Make sure the unit is unplugged while flushing,” recommends Stewart.
With window units, the cleaning process can be done entirely by yourself. The Department of Energy even suggests cleaning the cooling fins and condensate drains, since they can also affect how much energy the air conditioner needs to do its job.
Tips for maintaining your air conditioner
Like all devices, your air conditioner also requires regular maintenance and care. The manufacturer’s guide contains a wealth of information on how to clean and secure your machine.
If you’ve done all the above steps and the noise is still unbearable, something may be wrong. A faulty fan motor, compressor, and refrigerant leaks can cause loud whistling noises. Loud banging or crunching is not normal. It could be a loose part, something stuck in the engine, or it could be time to replace the compressor.
In these cases, turn off the unit, turn off the power source to the air conditioner, and contact a professional. Refrigerant leaks can be particularly damaging, so it’s best not to take chances. A licensed HVAC technician can help diagnose the problem and find a long-term solution.
