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My Air Conditioner Smells! What Are the Possible Causes and What Should I Do?

small_7655059318When your central air conditioner turns on, are there some nasty smells that come out of the air registers around your house? This is a problem that is not only unpleasant, but can also cause homeowners to worry about the condition of their cooling systems. Today we’re going to talk about why your air conditioner might start to smell and what you can do to prevent and fix the problem!

My air conditioner smells… what are the possible causes?

  • Your air conditioner is too big. If your air conditioner was not sized properly by a reputable HVAC contractor, it’s possible that your system is too big for your home. When your air conditioner is too big, it goes through quick cooling cycles and does not effectively dehumidify your air. This can allow mold to grow on or around your system, which can carry a stale and musty smell throughout your home.
  • Your condensate drain is clogged. One of the most common reasons that air conditioners begin to smell is that the condensate drain is clogged. The condensate drain is used to collect the condensation that drips off your cooling coils and drain it out of your home. When the drain is clogged, mold and mildew can grow in the drain pain and the drain lines and emit a smell that carries up into your system’s airflow.
  • Your cooling coils are dirty. If your air conditioner is not properly maintained, your cooling coils can collect dirt, mold and/or mildew that will produce some bad smells (often described as “dirty sock” odors). These smells are easily circulated throughout your home, because your air handler blows air directly over the coils.
  • Your air filter is clogged. Your air filter is designed to remove contaminants from your home’s air. Some of these contaminants can give off a smell, and if your air filter is clogged those contaminants will slip right by your filter and continue to stink up your home.

What can I do to stop or prevent my air conditioner from smelling?

As with most air conditioner problems, the best way to prevent your system from smelling is to schedule an annual tune-up every year. During a tune-up, we’ll check for all of the problems above and ensure that your system is clean and free of any nasty odors. Also, be sure to regularly change your air filter so that your system removes any smelly contaminants from your home’s air.

If you do begin to notice smells emitting from your air conditioner, be sure to give Jerry Kelly a call. We’ll send one of our NATE-certified technicians to your home to diagnose and fix the problem.

If you have any questions about why your air conditioner smells, or if you’d like a cooling system serviced or installed in your home, contact Jerry Kelly, your St. Charles, MO, air conditioning contractor. We provide service all over the St. Louis area, including towns like Lake St. Louis, Manchester and Maryland Heights.

photo credit: kikfoto via photopin cc