AC Compressor Noise: Causes and Solutions

Inland Empire Comfort
October 30, 2022

While occasional loud noises are typical with an air conditioner and compressor, you cannot overlook every AC compressor noise. Many indicate serious issues that can weaken your HVAC system's performance and, in some instances, even destroy the unit.


Unfortunately, it's impossible to distinguish the negligible sounds from the problematic ones when you don't know what causes them. That's why the air conditioning experts at Inland Empire Comfort, Claremont's trusted air conditioning repair team, break down the most common noises they hear from AC compressors and how you should treat each.


Rattling Noise

Rattling sounds are the scariest ones to hear from an AC compressor, but in most cases, they aren't the most severe.

Rattling often means one of the AC's internal parts is loose, and you need to tighten or reattach it. You can try to find the culprit yourself by removing the back cover and testing the components or calling for professional service. 


If you can't find a loose component and your AC still rattles, it likely means you need a new compressor. It's best to rely on experts for this; they can replace the component safely.


Clicking Noise

A clicking noise can mean several things ranging in severity, from dirt in the air compressor to a damaged or broken fan screen. A clicking AC compressor noise can indicate an electrical problem if you only hear it when first turning on your HVAC system.


Unfortunately, clicking has many possible causes and is nearly impossible to diagnose unless you have professional experience or weeks of free time for trial and error. However, the HVAC experts at Inland Empire Comfort will quickly get to the bottom of your AC's clicking sounds to prevent your AC from giving out.


Humming Noise

A humming AC compressor noise doesn't often mean your system has a severe issue, but you should still investigate the sound to prevent it from worsening. In most cases, humming means your AC's outdoor unit has a loose part or the compressor has low oil. Both issues are easy to fix on your own.


Squealing Noise

Squeals are standard when starting your air conditioner and aren't signs of an issue. However, if the squealing AC compressor noise lasts longer than 10 seconds, it could be a symptom of a severe problem.


Prolonged squealing often happens when air blows through one of your AC's worn-down components that have developed cracks or holes. Evaporator coils are the most common culprits, and you can identify them as the issue by listening for an accompanying bubbling noise. If you hear this, contact an HVAC company to replace the coils.


Buzzing Noise

A buzzing AC compressor noise typically means the unit has loose wires or a failing electrical current. Either issue can cause your AC to shut down at a moment's notice, so it's crucial to address the sound as soon as you hear it.


Unfortunately, not all buzzing noises come from electrical problems. Buzzing can also indicate a refrigerant leak or disconnected internal part. Therefore, rather than fumbling through DIY repairs that don't provide a definitive solution, it's best to call a professional to examine the unit.


Screaming Noise

This is the most severe AC compressor noise; if you notice your unit screaming or producing a loud, indescribable sound, turn your HVAC system off immediately and call Inland Empire Comfort for professional assistance.


A screaming AC compressor noise generally means a refrigerant leak or an excessive pressure build-up. Leaks can add to your utility bills and make you sick, while the pressure could destroy your entire system. Even worse, pressure build-ups don't have one universal cause, so diagnosing and fixing the issue is impossible without professional assistance.


You should also avoid refrigerant leak fixes without professional help. Refrigerant is a toxic substance that can cause dizziness and shortness of breath with enough exposure. Only an HVAC expert will have the skills to patch the problems before they cause health risks.


Get in Touch

Even though hearing an AC compressor noise isn't always the end of the world or your air conditioning system, you should always have an HVAC repair team nearby to fix the severe issues when they strike. Inland Empire Comfort can be that team for you if you live in Riverside, CA, or the surrounding areas.

 

Our experts will immediately diagnose your AC compressor noise and fix the issue on-site so you're not sweating through California's hottest days. Call today at (951) 336-1892 to schedule a service or learn about the different types of HVAC systems for your home.

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