As the warmth of spring finally arrives, lemonade stands line the streets, blooming hydrangeas can be seen out of every window, ice cream trucks can be heard coming around the corners, and homeowners are hurrying to turn on their air conditioning systems - only to be stopped in their tracks by an unpleasant odor. If this has happened to you, you know how disconcerting it can be: trying to figure out where the smell is coming from, what's causing it, and what you can do about it. Well, we'd like to help you get to the bottom of it so you can stop worrying and get back to smelling the hydrangeas.

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What's that smell?


If you are experiencing an odor coming from your ductwork, there are several potential culprits:

  • One of several culprits could be mold in your drip pan. Start by checking that your drip pan doesn't have any stagnant water sitting in it. If it does, then it's possible that you have a blockage in the condensate drain line. If the part of the drip pan where the condensation runs is not draining correctly, then unblocking the clog will help; or if the condensate drain line is the problem, then replacing the line should eliminate further problems as well as the smell. You might also want to consider a drip pan treatment that keeps your pan clean and free from overflows.
  • Another potential problem-causer is a phenomenon best known as Dirty Sock Syndrome, which links foul smells to your HVAC system's coils. Microbial decay builds up during certain times of the year when your heat pump warms in the morning and cools in the afternoon, producing condensate and fueling growth for microbes. The best cure for Dirty Sock Syndrome is a thorough coil cleaning by a NADCA-certified air duct and coil cleaning company.
  • If you have high humidity levels in your home, another popular source of bad odors is mold in your ductwork. The best way to make sure you don't have mold in your vents is by having an air duct cleaning and mold removal specialist come out and inspect your vents. If it's established that you have mold growing on the inside of your vents, then having them professionally cleaned is the best way to eliminate the issue.

It's not my drip pan, Dirty Sock Syndrome,or mold in my ductwork ... What else could it be?


When an unpleasant odor is coming from somewhere inside the house, many homeowners sometimes wrongfully jump to the conclusion that a dead animal is trapped somewhere in their ductwork - that's why it's important to check your drip pan and coils for buildup, and your ductwork for mold before signaling the cavalry. But ... every so often, the worst does happen; and then you have to figure out what to do when you find a dead animal in your ductwork. To find out what to do when you find a dead animal in your ductwork, check back with us next week for the second part of this two-part article!

More info? While you wait for next week's article, take a look at our post on Dirty Sock Syndrome: What is Dirty Sock Syndrome and How Can You Avoid It?

Call 877-800-2382 to speak with a knowledgeable customer service representative and/or to schedule an air duct cleaning, coil cleaning, or mold removal estimate with AdvantaClean today!

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