What Does That Sound Coming from Your Air Conditioning System Mean?

Posted on: 27 April 2021

Whether you have had your air conditioning system for a few months or a few years, you undoubtedly are familiar with what it sounds like when it is in operation. Some air conditioning systems will make a low humming sound that is barely audible at night and virtually inaudible during the day. Alternatively, other air conditioning systems will emit a faint fanning noise as air circulates out of its vents. Whatever latent sound that your unit makes, any changes to this noise warn you of hidden issues that could jeopardise the functioning of your AC. You may be surprised to learn that depending on the type of noise, you could discern what is ailing your unit and know why you need professional repairs! To help you with that, here are some of the noises your air conditioning system could produce and their potential meanings.


Any sizzling or buzzing sounds coming from your air conditioning unit should prompt you to switch off the system since these almost always stem from electrical issues. Firstly, you may begin to hear these noises when your AC system is operating with a damaged capacitator. Secondly, these sounds will come about when an electrical connection comes loose. It is critical to bear in mind that live wires in the AC unit should never be taken lightly, considering that this stem produces moisture. Hence, the best way forward is to turn off the system and call a technician immediately so that they can identify the source of the sizzling.


If you hear whistling noises occasionally, it usually is not a cause for concern since it is indicative of air hissing through the expansion valve and the ducts. Nonetheless, the moment that you catch this sound regularly, you should be concerned about two main issues. To begin with, hissing sounds become routine if you have an undetected refrigerant leak. You may also hear whistling noises when the AC's compressor is compromised. Since the compressor is tasked with circulating the refrigerant, the onset of any of these aforementioned issues will also impede the cooling ability of your air conditioning system. Hence, it is necessary to seek professional AC repairs so that the root cause is fixed before your air conditioning system stops working.


High pitched sounds such as squealing and screeching are usually signalling excessive friction within the air conditioning system. In some cases, you will hear these sounds when the AC system is operating with defective bearings or a damaged fan motor. In other cases, these shrill noises can be caused by a dislodged or an impaired belt. Whatever the origin, shrill, ear-piercing noises should have you enlist professional repairs as soon as possible, as your AC system likely needs replacing of specific parts.