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Don’t Let HVAC Noises Fool You: The Problem Could Be Worse Than it Sounds


Your HVAC system is responsible for maintaining the comfort of your Hilton Head, SC, home. Unfortunately, small problems can occur that signal a need for HVAC repair. It is important to notify your HVAC technician when you suspect a problem — it can prevent a small problem from becoming a large one. One way your system may be telling you that there is an issue is by noises it makes. If you hear any of the HVAC noises listed below, it is time to call for a repair.


Banging noises are never a good thing with any appliance. With an HVAC system, it is likely an indication of a loose or broken part, such as a connecting rod, crankshaft, or pin. These compressor parts can break off and damage other parts as they bang around. If it is not related to one of these parts, it also could be a sign that the indoor blower has become unbalanced or that the compressor needs to be replaced.


When the electrical components of your system start-up or shut down, it will cause clicking noises. But if you hear these noises constantly, that is not a normal part of the system function. You may have a problem with a thermostat that is failing or other electrical issues.


Buzzing noises can signify a lot of different problems going on in your air conditioning unit. It could be related to loose parts, debris caught in the outdoor unit, a failing outdoor fan motor, out of balance or lose fan blades, a dirty condenser coil, a dirty air filter, or even a refrigerant leak.


Squealing noises are often related to either outdoor fan motors or indoor blower motors, which will begin squealing loudly when they start to fail. Another part that might be the source of the squealing is a blower wheel or housing beginning to malfunction. Squealing can also be a common noise when your system starts up, but it should go away after a few minutes. If it doesn’t, you should contact a technician.


Humming sounds typically are not as serious as other air conditioner noises, but they still should be addressed to make sure that your air conditioning unit functions as efficiently as possible. This noise is usually an indication that something in your system is off. It could be a part that has just started to come loose, which can cause vibrations. These small problems can become major issues if they go unaddressed. A more concerning cause of humming in the system is electrical problems, such as loose wires, which should be addressed immediately to maintain safety.


Screaming noises or high-pitched whistling is a sign of a major and dangerous issue. If you hear this noise coming from your system, you need to shut it off immediately and call an HVAC repair technician. The most likely cause of this noise is a refrigerant leak, which can cause significant damage to your system and also cause major health concerns. Another dangerous issue it might indicate is high internal pressure in the compressor.


Another sign that there is a loose part of the system or parts that are out of balance is clanking. When you hear loud clanking, there is a possibility that the internal parts of the compressor have failed or the compressor itself has become loose. This will often mean that the compressor will need to be replaced. If the sound is not related to the compressor, it could mean that the indoor blower or outdoor blower fans have become unbalanced and are clanging against other parts.


If you hear some rattling in your system, it can be a sign of minor problems, like twigs or leaves clogging your outdoor unit or screws or bolts coming loose. It also can be a sign if major ones, such as your air conditioning unit deteriorating or problems with the electrical conductor. If you hear any of the noises above coming from your HVAC system, contact Old Coast Heating & Air Conditioning at 912-250-5771 today. Our knowledgeable staff will determine your repair needs and get your system back up and running in no time.