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What To Do If Your Outdoor AC Unit Is Making Noise

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Now that the weather is nice, you have likely started your central air conditioning system for the season. If so, you may notice that the appliance makes a few noises. Well, an excessively noisy AC system may require some extra care. Keep reading to learn about a few things you can do to reduce the noise.

Adjust The Fan

If you hear a rattling noise coming from the outdoor condenser, then the noise is likely coming from the fan. The condenser fan sits on the very top of the unit and pulls heat through the side vents, so it flows up and out of the device. This fan stays on as long as the condenser is working, so it gets a lot of use. The fan will often loosen from the main hub that keeps it in place, so a bit of tightening may be enough to reduce the noise. 

Use a screwdriver to release the screws from the top casing or cover. Pull up the cover to expose the pan and locate the screw, bolt, or another connector that sits on the central hub section of the fan. Tighten it and then use your hands to try to wiggle the fan to see if it is secure. You should not be able to move the fan vertically, but it should spin with ease.

At this time, you also want to make sure the fan is clean. A dirty fan can create some noise, so use a clean cotton cloth to wipe away debris stuck to the blades. You want to make sure the blades are straight and not crooked, so look for an uneven surface when you spin the fan around. If one blade looks uneven, then use your hands to gently bend it back in place. Fan blades that are excessively bent may require the replacement of an entirely new fan unit.

Have The Compressor Checked

The AC compressor is one of the working parts inside the unit that can fail over time. Failure is common after extensive use, so old age is really what stops the part from working.

The compressor has a lot of moving parts that can make noise as they break down. The piston will make the most noise. This is the part that squeezes the coolant until it changes from a fluid to a gas. As the piston wears, it will scrape against the side of the compression chamber and make a screeching noise. Also, the old compressors will often vibrate as they run and create a lot of noise.

If you think the compressor may be responsible for the sounds you hear, then the part will need to be checked and possibly replaced. This is not something that you can do since the coolant will need to remain under pressure as the job is completed. So, speak with an air conditioning repair professional about this. 


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