6 Air Conditioner Sounds That Indicate Trouble

August 27, 2020

Troublesome Sounds From Your Air Conditioner

our air conditioner can make many different sounds, many of which indicate a problem somewhere in the system. How do you know which sounds are normal and which require the attention of an HVAC contractor in Sonoma and Marin County?

 
Normal air conditioner sounds are generally unobtrusive. You should hardly notice the subtle whoosh that occurs as the unit begins its normal cycle. If the air conditioner is making sounds that are disruptive, that is the first indication that something may be wrong. Here are some examples of specific sounds that your air conditioner may make and what they might mean.


1. Clicking

This is a sound that you may observe from your unit outside. Repeated clicking from the external AC unit indicates that the relay that actuates the compressor is malfunctioning or wearing out. This problem may be difficult to recognize because at first the clicking may be brief. Left unchecked, the problem can continue to get worse until eventually the AC will not turn on at all due to a complete failure of the relay.


2. Rapid Cycling

In this instance, the sounds of the air conditioner shutting itself on and off are more or less normal, but it draws attention to itself by repeating the cycle more often than usual. Over the course of an hour, a normally functioning air conditioner should cycle on and off three to four times. Anything more often than that could be an early signal of trouble somewhere in the system. With prompt evaluation, it may be possible to correct it before it requires a complete replacement.


3. Rattling

A rattling noise from the air conditioner indicates that something somewhere in the system has come loose. It could be a segment of the ductwork or a moving part in the blower. The point in the cycle where the rattling noise occurs could indicate where the loose component is located. A loose blower part is more likely to cause rattling as the system cycles on.


4. Squeaking

A problem with the indoor handler's drive belt or its pulley may cause a squeaking or squealing noise. You may notice this sound transmitted through the system's ductwork. Correcting the issue may require an adjustment, or the entire component may need to be replaced.


5. Hissing or Bubbling

It is normal for an air conditioner to emit short, small hissing noises during operation. However, if the hissing lasts longer, is louder, or is accompanied by bubbling sounds, it suggests a leak in the system. This requires attention right away.


6. Screeching

Distinct from squealing or squeaking, screeching is a high-pitched noise of metal on metal. It indicates a leak of refrigerant, which poses a safety risk to you and your family. If you ever hear a screeching noise from your AC, turn it off immediately and contact a professional.


Next Level HVAC Contractor in Sonoma and Marin County

The problems that cause your air conditioner to make noise don't get better if you ignore them. They are more likely to get worse. For more information about air conditioner repair or replacement, contact us at Next Level HVAC by calling 707-228-9921 or using our online form.


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