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7 Common Causes of Air Conditioner Clunking Noise

air conditioner clunking noise

You come home from a long day at work and sit down to relax in the cool comfort of your home. Suddenly, you hear a loud clunking noise coming from your air conditioner. You know it’s not supposed to make that noise, and it’s definitely not a good sign. But what could be causing it?

In this blog, we will discuss the seven most common causes of AC clunking or hissing noises. From loose parts, to worn-out components, we have got you covered. We will explain each cause in detail and give you tips on how to fix or prevent them. Don’t let a noisy air conditioner ruin your peace of mind. Read on to find out more, and call All Weather Heating & Air Conditioning for all of your AC needs!

Understanding Loud Air Conditioner Noises

Air Conditioner Loud Noises

When your air conditioner starts making clunking noises, it can be frustrating and concerning at the same time. Understanding the root cause of these sounds is crucial to ensure that your system functions correctly and does not suffer further damage. Identifying these issues early on can help you prevent costly repairs and replacements in the long run.

Outdoor Unit Loose Parts

Loose parts are a common cause of air conditioning noises. These can include screws, bolts, and belts that have become dislodged or damaged over time. Not only do loose materials create irritating sounds, but they can also cause damage to other components if left unaddressed.

Regular AC maintenance from a professional HVAC technician can help prevent loose parts from causing significant problems in the first place. If you hear any unusual noises coming from your AC unit, contact a professional immediately to diagnose and address the issue before it becomes worse.

Scroll Compressor Issues

Scroll compressors are an integral part of AC units and can cause clunking noises if not maintained properly. These compressors function using two interleaving scrolls to compress refrigerant gas and circulate it through the system. However, common issues such as wear and tear, lack of regular maintenance, or incorrect installation can lead to clunking noises.

Diagnosing issues with scroll compressors can be difficult without the help of a professional HVAC technician. So be sure to reach out to your local expert for routine maintenance and cleaning of the unit so you can prevent these issues from arising in the first place and avoid costly compressor replacement.

Faulty Fan Blades

Worn-out or misaligned fan blades can cause clunking, banging noise, or knocking noise in your air conditioner. This can lead to decreased performance and potential damage to the unit. Although regular tuneups and cleaning can prevent issues with fan blades, if you hear clunking noises, it’s important to have a professional inspect and repair the issue promptly.

Don’t ignore these sounds, as they can lead to bigger problems. Trust an experienced HVAC technician to address any issues with your air conditioner’s fan blades for optimal performance and longevity.

Air Conditioners Refrigerant Leak

Air Conditioners Refrigerant Leak

Maintaining the right level of refrigerant is crucial for your air conditioner to function optimally. Low refrigerant levels can cause clunking or hissing sounds to come from your AC unit. The evaporator coil can even freeze up, due to clogged or dirty air filters, leading to strange sounds. Additionally, a malfunctioning compressor can produce loud and unusual sounds.

Loose or damaged parts such as belts and bearings can also lead to rattling noises, knocking sounds, or a buzzing noise. Electrical issues such as faulty wiring or a failing capacitor can also cause strange noises from the AC. Regular maintenance and cleaning can prevent these issues, but if you hear any unusual noises, it’s essential to have a professional inspect and repair the issue promptly to avoid further damage.

Blocked or Dirty Condenser Fan/Coils

Maintaining a clean and unobstructed condenser fan and coils is crucial for the efficient functioning of your air conditioner. When dust, debris, or other particles accumulate on the coils, it can cause clunking noises and reduce the efficiency of your unit. Neglecting regular maintenance of your air conditioning unit can lead to dirty coils and subsequent sound issues such as knocking, squealing, rattling, and humming noises.

Scheduling regular cleaning of the condenser unit by a professional technician can prevent clunking noises and improve cooling efficiency. Additionally, investing in a high-quality air filter can help reduce debris accumulation on the coils, minimizing noise levels and improving overall system performance.

Electrical Issues

Problems with electrical components can lead to clunking or clicking sounds from your air conditioner. Loose wiring connections can cause electrical arcing and create a clunking noise, while faulty capacitors can make the compressor start and stop abruptly, resulting in a similar sound.

An old or damaged contactor may also lead to an intermittent power supply and make a clicking or clunking noise. If you suspect any electrical issues with your air conditioning system, it’s essential to get them inspected and repaired by an experienced professional as soon as possible.

Worn Out Parts

AC Worn Out Parts

Worn-out parts are a common cause of air conditioner clunking noises. Fan motor and blades, motor mounts, blower motor, compressors, and belts can all wear down over time and produce unusual sounds as they malfunction. 

Blower motors pull in warm air to be cooled, and then push cool air throughout your home. Over time, its mounts can loosen, causing the blower wheel to bang against its metal casing. Without proper mount support, the blower wheel becomes off-balance whenever the fan slows down during the air conditioner shutdown process.

Neglecting worn-out parts can lead to further damage and more costly repairs.

Need Help With Your Air Conditioner? Call All Weather Heating & Air Conditioning Today!

At All Weather Heating & Air Conditioning, we understand the importance of having a fully functional AC system. If you’re experiencing clunking noises from your AC, don’t hesitate to give us a call. Our team of experienced technicians is always available to diagnose and repair any issues with your AC system promptly.

We’ll work quickly and efficiently to get your system back up and running, so you can enjoy a cool and comfortable home or office. Contact us today to schedule an appointment!


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