Why is My Air Conditioner Making a Loud Buzzing Sound?

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Why is My Air Conditioner Making a Loud Buzzing Sound

Why is My Air Conditioner Making a Loud Buzzing Sound?

When your air conditioner is working properly and efficiently, it should not produce any sound louder than a low hum. If you hear a strange, distracting buzz from your AC unit, it’s usually an indication that something is wrong.

There are several issues that can lead to a buzzing sound from your AC unit. While some are simple, others may be quite serious, requiring an immediate call for professional air conditioning repair services.

Check out these 5 common reasons why your AC is making a loud buzzing sound:

1. Condenser Fan Motor Issue

When your AC unit is turned on, the condenser fan blows air from the outside unit. If the fan blades are not turning but the inside blower is working fine, the compressor motor may emit a loud buzzing noise. Loose parts, a malfunctioning fan, or debris inside the unit can all prevent the blade from turning. In this case, it’s best to call a professional HVAC services contractor to trace down the problem.

2. Loose AC Parts

air conditioning repairYour AC system is made up of many moving parts and occasionally, the components can vibrate so much that they come loose. Even tiny parts can sometimes affect the performance and efficiency of your AC, and can also lead to more expensive issues over time.

3. Frozen AC Unit

An air conditioner that runs continuously for long periods of time can freeze up, creating a loud buzzing noise. If this happens with your unit, turn it off right away and let it thaw. It should be up and running again without issue after a few hours of being off. Refrigerant leaks may also lead to frozen coils so if this happens frequently, schedule air conditioning repair services immediately.

Read more about frozen coils here!

4. Damage to the Isolation Foot

The AC compressor is almost always mounted on the base of the AC unit. It sits on a small rubber foot, also called isolation foot. Over time, the rubber on the isolation foot can crack or deteriorate. This results in the compressor being unbalanced–producing a buzzing noise when operating.

5. Compressor Malfunction

Your air conditioning unit’s compressor works to pressurize and cool the refrigerant. If there’s a buzzing sound, it may indicate that the compressor is not working as it should. It’s also possible that the electrical voltage is not at the correct amperage.

If you hear a buzzing sound from your AC unit, check if the noise only starts when certain settings are enabled. There may be a faulty part or faulty wiring (i.e. loose or exposed wire) that produces the noise. It’s best to call for professional air conditioning repair services to have your system properly diagnosed and fixed.