Dirty Sock Syndrome – What is it and how do I get rid of it?

Dirty Sock Syndrome – What is it and how do I get rid of it?

It’s a hot, humid day.  You come inside and head straight for the AC looking for some relief from the heat.  You push the on switch and sit back…. but wait a minute!  Did someone just let something slip?  Is that the trash?  Is the laundry running over with dirty socks?  Whatever the case, your relief from the heat is now an assault on the senses. 

What you’re experiencing is what many in the HVAC world have come to call ‘Dirty Sock Syndrome’.  While this may seem humorous, this is no joke.  This is a real problem that has serious health implications.  So, whether you’re using a window AC or a ductless mini-split system, at some point most of us will have to deal with the awful stink that comes from the dreaded ‘Dirty Sock Syndrome’.   But what causes this to happen and how can we treat it?  Let’s find out.



Basically, this condition is caused by your AC or ductless mini-split system being dirty.  When your unit sits dormant for a little bit of time, environmental factors within these units, such as mold, mildew, and even bacteria can grow and set up camp inside the inner components like the coil.  When this happens, a foul odor is emitted when you turn on your system and the blower forces air past any contagions. The things causing the smell are now being blown around your home for you and your loved ones to breathe in.  This is especially concerning for those who have allergies, a breathing disorder, and/or are immunocompromised.   

Some people hope that this condition will go away on its own but don’t be fooled simply because you run your system for a while and the smell subsides.  The same contagions, mold, mildew, and bacteria that were residing on the inner components of your AC or ductless mini-split are still there.  The fact is, ‘Dirty Sock Syndrome’ can happen when you run your system on the cool settings, and if you have a heat pump, when you run your system on the heat settings.  So, don’t count on the smell to go away with the seasons.  The only way to get rid of this is to do a thorough cleaning.



A thorough cleaning is going to help.  This means getting into the inner workings of your AC or ductless mini-split. 

Cleaning Check List:

  • First, have a regularly maintenance program in place
  • Have your air filters regularly checked and cleaned
  • Make sure the drain pan is clean and free of standing water
  • Use a detergent to clean the condenser coils and be sure the fins are free of debris
  • Clean the fan blades and if you have a ductless mini-split remove the blower wheel and thoroughly clean it

When considering the list above, many people opt for a professional to do this work, so if you’re not a DIY kind of person then it’s probably a good choice to let the professionals do the cleaning. 

After your unit is cleaned then it’s time to take preventative measures to keep things clean.  A great way to help keep your system clean is to use the PureAC.  Used on a regular basis (weekly to bi-weekly), PureAC will help keep the inner components of your AC or ductless mini-split disinfected and free of the contagions that cause Dirty Sock Syndrome.  How you ask? 

It does this by using the same technology used in many industries such as:

These industries commonly use ozone technology to kill bacteria, mold, and mildew, (aka: contagions).  Activated Oxygen or Ozone (aka: O3) is a gas.  When ozone gas molecules meet the cell wall of a contagion, the cell wall is attacked.  The cell wall of contagions is essential because it ensures that the organism can maintain its shape and keep living.   As the ozone gas molecules contact the cell wall, oxidation takes place and it bursts through the cell wall in just seconds.  This attack breaks the contagion, it loses its shape, and then dies (see illustration below).  With the contagion now destroyed you are now left with a product or device that is safe, deodorized, and sanitized.  Ozone is commonly used by industries because its natural and highly effective, giving a greater than 99.9% kill rate for bacteria, viruses, and molds.  In other words, goodbye ‘Dirty Sock Syndrome’.



‘Dirty Sock Syndrome’ stinks!  This condition is real and it has serious health implications.  Thankfully, we now know that we don’t have to be unarmed victims of this condition. With regular maintenance and cleaning we can use our window AC or a ductless mini-split system without the discomfort or worry of circulating dirty air into our rooms and homes.  In conjunction with a regular maintenance and cleaning schedule, we recommend using PureAC regularly as a proactive way to keep ‘Dirty Sock Syndrome’ where it belongs, in the locker room, not your home. 

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