Mold Inspections of HVAC Systems
At Angstrom Testing Services, we specialize in evaluating hygienic conditions inside HVAC Systems. We also specialize in performing full hygienic refurbishments of fan-coil-type forced air heating and cooling units, air handler units, and supply and return trunks/ducts that have become heavily impacted with dust/dirt and mold growth.
Over time, elevated levels of dust and dirt impact and accumulate onto the fiberglass insulation lining the walls of the blower wheel and cooling coil compartments and onto the upstream and downstream sides of the coil inside the air handler. The fiberglass duct liner inside the initial run of the supply trunk is also highly susceptible to mold growth conditions. The impacted dust and dirt serve as ideal nutrients to support black and other molds in the presence of recurrent moisture, which typically exists inside the air handler and supply trunk.
Under the above conditions, mold spores and mold-related-odors are pushed through the supply ducts by the blowers when the air handler is on, and the spores and odors are distributed throughout the rooms of the house. The mold spores may cause allergic type symptoms, such as difficulty breathing, wheezing, tightness in the chest, and sinusitus in sensitized individuals.
In older air conditioning units, the fiberglass insulation maybe deteriorated. When this happens, there is the potential for glass fibers to become entrained into the the airflow and be distributed into the rooms of the house when the HVAC is on. Microscopic airborne glass fibers can be inhaled by the occupants and cause upper respiratory problems, and eye, nose, and throat irritation.
Maintaining the drainage system is also important. Drip and condensate pans must be kept clean and drain hoses must free of clogs, otherwise the condensate pans will overflow and the sheetrock ceiling beneath the AC system will sustain water damage and become moldy requiring mold remediation work.




Hygienic Refurbishment of Air Handlers
When visible mold or damaged fiberglass insulation is present inside air handlers or surface mold testing indicates that A/C ducts are colonized by mold growth, a full hygienic refurbishment and mold remediation may be necessary. Flex ducts, which are virtually impossible to adequately clean, probably should be replaced.
A full hygienic refurbishment includes:
-Removing, cleaning, disinfecting, and re-installing the blower wheel assembly
-HEPA vacuuming and disinfecting both the upstream and downstream sides of the cooling/heating coil
-Removing and replacing moldy and/or deteriorated fiberglass insulation inside the blower wheel, cooling coil and air return/supply compartments
-Cleaning/disinfecting the condensate and overflow pans
Very few HVAC and mold remediation companies have the necessary skill set to perform this work, and they are mainly concerned with the functionality of the unit and not its hygienic condition.
Visible mold on your drywall, carpet, or basement walls is trouble. But mold in HVAC (heating, ventilation, air conditioning) systems is a real danger to you, anyone living in your home, and even your pets (yes, some pets are allergic to mold; they can have the same reactions to mold exposure as humans). If you have mold in your HVAC system, when your furnace or AC operates, the blower comes on and the airflow spreads mold spores throughout your entire home. Mold spores will contaminate every room and every space. The longer the system operates while contaminated, the worse your mold problem can become. Extensive mold remediation work and cleaning work may then be necessary.