What is Dirty Sock Syndrome?

You turn on your air conditioner and you smell......dirty gym socks. What is happening? While "Dirty sock syndrome" sounds like a colloquialism, it's the official term heating and air conditioning professionals use for this problem. The odor comes from your vents, fills your house, and resembles the smell of a sweaty gym locker room. Needless to say, this is not a problem anyone wants, especially when trying to relax in their own home.

What Causes Dirty Sock Syndrome?

Dirty sock syndrome is caused by bacterial buildup on your HVAC coils. Unfortunately, you won't be aware the buildup is there until the odor begins to form.Generally, the odor happens when one of two things occurs:

  • Your heat pump goes into defrost mode for the first time that season. This generally happens the first time the temperature goes below 40 degrees in the fall or early winter.
  • Your system is switching back and forth from heating settings to cooling settings in the same day. This is more likely to be a problem in Austin, where winters are mild, but spring can give an extended period of seventy or eighty-degree daytime temperatures, whilst still dropping into the fifties at night.

Essentially, the temperature of the coils drops and humidity increases. The buildup of bacteria then produces this smell. The smell will go away if the system is run entirely on heat or entirely on cold for a while; however, this only fixing the symptom, not the problem.Gas furnace systems are generally not prone to dirty sock syndrome because the higher temperatures prevent the bacteria from building up. Also, not every system develops dirty sock syndrome. It is more likely to occur if there are high levels of humidity in the home, or if you have pets. The issue is also most common in the Southeastern region of the U.S.

Does It Mean My System Is Broken?

No. Dirty sock syndrome is not a symptom of mechanical/electrical issues with the system itself.

Can It Affect My Health?

Dirty sock syndrome, while unpleasant, is generally not dangerous. However, it can cause problems for asthmatics and people with a weakened immune system. The problem can also spread through your ducts, resulting in a much greater health threat. If ignored, the spread through the system can become expensive to address.While mold in your ducts can cause coughing and wheezing, even in otherwise healthy people, dirty sock syndrome has to go untreated for quite some time before becoming dangerous.

Can I Get Rid of Dirty Sock Syndrome Myself?

We don't recommend attempting to get rid of dirty sock syndrome on your own. Instead, we recommend calling our team of experts. To prevent the problem from returning, we recommend having the Nu-Calgon "iWave R" product installed. A fairly new but proven product, iWave R prevents dirty sock syndrome instead of just providing a temporary solution that needs to be repeated every year.

How Can I Keep It From Coming Back?

You should make sure your ducts are properly sealed to help keep out microbes and spores (this will also lower your bills), consider upgrading to a more efficient filter (especially if somebody in the house has allergies or asthma), and have your system inspected and cleaned regularly. Make sure that you have your filters changed at the frequency recommended by the manufacturer. If you also have other problems associated with high humidity, installing dehumidifiers can be helpful.If your HVAC system appears to have dirty sock syndrome, especially if you tried cleaning it yourself and it didn't help, you should contact an HVAC professional. At Stan's Heating, Air & Plumbing, we have the right expertise to confirm that dirty sock syndrome is the problem, fix it, and help ensure that the problem does not return. Contact us to schedule an appointment, so we can look at your HVAC system and get things smelling sweet again as quickly as possible. All of our repair estimates are free and come with no obligation!

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