Mold in Air Ducts
The Environmental Protect Agency (EPA) warns that moisture in air ducts can lead to mold in air ducts and biological contamination. There are a couple of ways that moisture can get into your system. First, it can enter through leaks in the duct system that can occur over time, or because of improper installation. Second, condensation forms on a cooling coil during the air conditioning cycle. When the coil is dirty this condensation will blow off of the coil and travel downstream into the ducts. Also a dirty coil can freeze up like the picture below. When the coil thaws it can leak significant amounts of water into the ducts.
Generally, a thorough cleaning of the dirty air conditioning coil and duct system will clear up the problem. Also, if your air ducts are leaking, new technologies are available to seal them up with no mess or reconstruction. It is also advisable to make sure that your air ducts are properly insulated.
These tips can keep you and your family healthier. An added benefit however, is greater comfort and energy savings.