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4 Likely Causes for a Buzzing AC Unit

Posted on July 12, 2017 by Chris Lancaster

fix buzzing AC unitWhen it’s working efficiently and correctly, your air conditioner should not produce any noises louder than a low hum. If you hear a loud, distracting buzz from your AC unit, that is a sign that there is something wrong. Several issues can cause a buzzing noise from your AC unit. Some are very simple fixes, while some are very serious.

What’s the Buzz I Hear from My AC Unit?

The team at Lancaster Brothers has put together this list of possible causes for buzzing to help you diagnose your system:

1. Your AC Unit is Frozen

When the air conditioner is running for long periods of time, it can freeze up, which will cause a loud buzzing sound. If this happens, turn off the unit to let it thaw. After a few hours of it being off, it should be running again without issue when you switch it back on.  Refrigerant leaks cause the unit to freeze, so if this happens frequently, or it is still buzzing after a few hours, professional assistance is needed.

2. Your AC Unit Has Loose Parts

With so many pieces moving in conjunction inside your air conditioner, parts sometimes vibrate loose. While it may seem like no big deal, missing or loose parts can affect the efficiency and performance of the unit and lead to more expensive problems over time.  

3. Your AC’s Condenser Fan Motor isn’t Working Properly

The condenser fan is the large fan that blows from the outside unit when your AC unit kicks on. If the inside blower is working but the fan is not turning, the fan motor will emit a loud buzz. Debris inside the unit, a failing fan, or loose parts can all be reasons for why the blades aren’t turning.

4. Your AC Has Electrical Issues

Electrical issues are also common causes to loud buzzing sounds. One of the easiest electrical fixes is replacing the contractor relay switch which is a low-voltage switch in your exterior unit that is controlled by the interior thermostat. When it goes out, it will create the loud buzz. However, more serious electrical problems, such as aging or loose electrical connections can also cause the buzz from the unit. If those aren’t repaired, they can lead to more serious problems, including electrical shorts.  

Call Lancaster Brothers for Fast AC Fixes

A loud buzzing sound is a sign there is something wrong with your air conditioning unit.  If you hear this noise, turn off the unit immediately, and give us a call. Here at Lancaster Brothers, our professional and experienced technicians are available to diagnose the problem quickly and fix it fast. From routine maintenance to keep your system running in top condition to replacing your AC unit, Lancaster Brothers will get your house cool and comfortable in no time.  

We Install Quality Lennox Air Conditioners and Furnaces

LennoxIf your AC is on its last leg, give us a call. Our experts can set you up with a system that is the right size for your home and your budget. Check out the savings on Lennox systems on our Specials page.

If you need AC repairs or replacement, call the professionals at Lancaster Brothers at (913) 851-3399 or contact us online and we’ll be there to fix it fast!

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