What to Do When Your Central Air Conditioner Smells Musty?

central air conditioner smells mustyIf we are lucky, our air conditioners run smoothly in the background without us ever noticing them. Unfortunately, there is one problem with an air conditioner that can cause massive disruptions to your life: unexplained, strong odor. Air blown from a central air conditioner that has a foul odor may result from an underlying issue with your system that deserves immediate attention, both to improve the quality of your air and to protect your family’s health. If you notice that the air from your central air conditioner smells musty, keep reading to learn some of the most common causes and how to address them.

Swap Out Your Air Filter

When you run into a problem with your central air conditioner, including an unexplained odor, it is best to try the simple fix first. One of the most typical causes of a smell from an AC unit is build-up on your filter. Over time, a filter can accumulate dirt, debris and even bacteria, which can result in an unpleasant odor when air passes through. For a quick fix to that mysterious aroma that happens whenever your air conditioner turns on, you might need to change an air filter. If you are lucky, this will immediately improve the quality of your air and save on more expensive repair solutions.

Clear Your Ducts of Moisture

Ideally, thanks to preventative maintenance, problems with your central air conditioner should have been addressed before they begin. Unfortunately, these problems do crop up, and a maintenance issue that may be causing the odor to come from your unit is moisture in your ducts. Due to improper insulation, moisture can build up in your air conditioning ducts causing mildew to form. Once mildew sets in, it produces a very distinct odor that is decidedly unpleasant. Check your ducts for moisture and mildew, and clean them out if you find anything. The chances are that this will completely solve your air conditioner’s odor problem. 

Learn About ‘Dirty Sock Syndrome’

Although it is not as familiar as it should be, there is actually a term for certain air conditioner smells. It is what’s known as ‘dirty sock syndrome’, and it might be the source of your air conditioner’s fragrance problem. Dirty sock syndrome results from bacterial decay inside your air conditioner. Microorganisms build up inside of your air conditioner, begin to decay, and then put out a strong aroma that smells a lot like an old pair of socks that have been buried in your laundry basket for an extended period—hence the name. Making sure that your central air conditioner gets regular cleaning and maintenance will help you avoid dirty sock syndrome so that the air in your home stays fresh. 

Get Your Unit Checked Out by a Technician

As we have seen, there are a number of reasons that your air conditioner might be emitting a foul scent. While some of the causes are relatively simple, others, like mildew, can turn very serious very quickly, making it difficult to live in your home and possibly putting your family’s health at risk. To address these issues and return the freshness to your home’s air, you need the help of Phoenix Arizona air conditioner repair technicians. Experienced, knowledgeable air conditioner professionals will be able to detect the cause of your system’s gross smell and take care of it as quickly as possible.


Contact the AC repair experts in Phoenix at Hays Cooling Heating & Plumbing to get your air conditioner back up and running. Email us or call (602) 661-9350 now!


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