Air conditioning ducts (and especially swamp cooler ducts) are notorious hiding places for mold. The humid air (often laden with mold spores) passes over the cooler metal ductwork and causes water to condense and pool creating idea locations for mold to grow. That’s why it is important to have your air ducts cleaned periodically.

You should consider having the air ducts cleaned if: There is substantial visible mold growth inside hard surface ducts or on other components of your heating and cooling system.

Make sure the service provider you call has considerable experience with duct cleaning — there are lots of fly-by-night companies that say they can do the job, but don’t. In addition, keep the following points in mind:

  • Many sections of your heating and cooling system may not be accessible for a visible inspection, so ask the service provider to show you any mold they say exists.
  • You should be aware that although a substance may look like mold, a positive determination of whether it is mold or not can be made only by an expert and may require laboratory analysis for final confirmation. For about $50, some microbiology laboratories can tell you whether a sample sent to them on a clear strip of sticky household tape is mold or simply a substance that resembles it.
  • If you have insulated air ducts and the insulation gets wet or moldy it cannot be effectively cleaned and should be removed and replaced.
  • If the conditions causing the mold growth in the first place are not corrected, mold growth will recur.

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I am the parts manager at Paradise Marine in Gulf Shores, Alabama, and have had Mold Off® in the ships store since 2009 and never had tried it or recommended it to my customers. I promise you now, it is now high on my list and will be the only product I recommend for mold removal. Thanks for making a great product!

- Lynne Siler, Parts Manager, Paradise Marine Center