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Why Is Your Air Conditioner Making That Noise?

The last thing you want to hear is a new noise coming from your HVAC system. Unfortunately, many noises tied to your HVAC system indicate larger problems, which is why knowing what each sound means is so important. Here are a few noises you might hear and what they could mean for your air conditioner.

3 Common HVAC Noises & What They Could Mean

  1. Buzzing

A buzzing noise coming from your HVAC system could mean problems with your outdoor unit’s fan. When the fan blades come loose, they can create friction with the passing air, making a buzzing noise. A buzzing sound could also indicate that there is debris in the fins of your outdoor unit or the motor that powers the fan is about to fail. Unfortunately, when your refrigerant lines develop leaks, it can also create a buzzing noise.

If your air conditioner is making a buzzing noise, perform a quick physical inspection of the outdoor unit. Remove plants that may be growing close to the system, and consider spraying down the fins to remove leaves or twigs that could be stuck.

  1. Clanking 

Clanking is a sign that something within your HVAC system may be out of balance. Sometimes, the air compressor welds become damaged, allowing your system to rock back and forth and come into contact with the sides of the unit. Over time, this movement can cause even more damage, which is why it is so important to have clanking checked immediately by an HVAC professional.

  1. Squealing

Squealing can be a sign of poor airflow or gaps in existing vent work. When air tries to escape through these areas, it can cause friction that creates a loud squealing noise. Additionally, failing blower wheels can also contribute to a squealing noise. Pay attention to where you notice squealing noises, and report the issue to your HVAC expert.


At Blue Ox Heating & Air in Minneapolis, MN, we can help you with any issues you might be having with your HVAC system. Our team has more than 100 years of combined experience diagnosing and resolving a long list of HVAC concerns, ranging from sudden system outages to air quality problems. Additionally, we love giving back to veterans, active military, and first responders by offering complimentary inclusion in Our Honor Club, giving them access to free monitoring and inspections of their plumbing, HVAC, and electrical systems. Find out more about how we can help by visiting our website or calling (612) 326-3837.