The presence of mold in an HVAC system is a common complaint.  Mold is a sneaky little bugger. It can grow and proliferate and make building occupants sick without ever being seen. And the fastest way to spread mold through a building is through a forced-air HVAC system.

The reason this complaint is so common is that mold is always present in your buildings and your HVAC system to the extent that it is present in your building’s environment. There will be more molds in humid weather and less in dry weather. You will never get rid of it completely, but you can control it. All it needs to grow is moisture and food. Take those away and the mold goes away.

According to the U.S. EPA, you should routinely inspect your HVAC systems, not just for mold, but for moisture. Look at drain and condensate pans to make sure they are draining properly. If they are plugged, the moisture that accumulates will become a mold factory. Also make sure that all HVAC ducts and system components such as air handlers, blowers, plenums and the like are free of any moisture.

If, despite regularly inspecting your system, you are still getting complaints about it (mold starts to grow in as little as 48 hours), here are some tips for cleaning it up:

  1. Turn off your HVAC system.
  2. Everyone involved in this cleaning should wear at least an N-95 respirator.
  3. Replace anything porous, such as filters or insulation that has become wet.  Double-bag the waste using at 6-mil or thicker plastic bags.
  4. Use wet vacuums to clean out any standing water.
  5. Use an EPA registered disinfectant labelled for HVAC use to clean nonporous surfaces (duct work, coils, plenums, pans, etc.) of mold, mildew and other dirt. Goodway’s MoldTek ready-to-use disinfectant and mold cleaner will kill and remove mold, mildew and odor causing bacteria.
  6. As an added measure, isolate each section of ductwork you clean with bladders so the spores you stir up during cleaning don’t spread to other parts of the system or the building. Fog the area with an EPA registered disinfectant.
  7. Apply a mold and mildew inhibitor to all components of the HVAC systems. Again, this must be EPA registered and specifically labelled for use in HVAC systems to limit risks associated with using the wrong chemicals and cleaners in HVAC systems. Goodway’s CoilShine-BC is EPA registered for use in HVAC systems to control mold growth for up to 2 years.
  8. As a final step, HEPA vacuum anything that you cleaned up.

Source: HVAC

Aspen Environmental recommends air duct cleaning and mold inspections be done by a certified professional. For professional help with duct cleaning, duct leaks, mold testing, or mold removal please call (800) 931-6653 or email info@aspenenvironmentalservices.com.