Shutting Down HVAC Units During Summer Can Make Children / Staff Sick from Mold

As our family and friends are getting ready for their kids to go back to school, one question that seems to always come up year after year is, why do kids and teachers seem to get sick after their first few days back to classes?

This can be due to ?sick building syndrome? and can be prevented by performing thorough maintenance and cleaning before starting up school HVAC equipment.

In order to stick within budgets, many schools shut down HVAC units during the summer to help cut cooling costs. However, this can often lead to more expensive problems later in the year, because microbial ecosystems can grow on these unused units, in addition to making the equipment itself less efficient once it is started back up. Alan Wozniak of Pure Air Control Services Inc in Clearwater, FL mentioned that, ?some schools turn off their systems completely, while others simply increase the building temperature when students are not present. This saves energy and money but can have consequences such as higher humidity levels, musty rooms, and microbial growth on building surfaces, furnishings, and HVAC systems.?

This can cause something called ?dirty sock syndrome?, where a musty odor permeates throughout the facility due to microbial growth. It can?crate allergy-like symptoms, like coughing, sneezing and wheezing in especially sensitive individuals. These symptoms are what is what we referred to as ?Sick Building Syndrome,? which people experience at the start of the school year.

Even after the moisture is gone, dormant mold spores can grow again once moisture is reintroduced, like when school begins and children are present. In addition to the health effects, the equipment is negatively affected because when an HVAC system sits idle, the bearings and shafts or any lubricated parts have to run for some time before reaching peak efficiency again.

To prevent these issues, it is recommended to perform routine cleaning and maintenance on all units, but especially on the coils. This will also include replacing the air filter, cleaning indoor and outdoor coils, adjusting the dry package, and changing the fan belt. Studies have shown that if these methods are not in use, the electrical load of the coils can increase by up to 40 percent- therefore reducing cooling capacity and increasing your energy bill. The building should also be manually dehumidified to keep up with latent moisture removal needs, and a topical antimicrobial application can also be applied to hard surfaces to prevent mold growth. Installing a UV-C light over coils can also help prevent mold growth and therefore improve unit efficiency and indoor air quality.

If your kids are experiencing the symptoms mentioned above, you may need a company like MVP Environmental Solutions to take a closer look to find the hidden mold.

Not all mold can be easily found, and the parts of an HVAC or AC unit often have to be disassembled to find where the mold is hidden and dispersing from. If you suspect that you may have hidden mold growth, don?t hesitate to call us at any time of the day and remediate the situation right away before occupants start feeling sick.

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Evaporator coils that have accumulated mold and dust. Photo courtesy of ACHRNEWS RSS

Anesi, Jen. ?Starting Up Idle HVAC Equipment after Summer Vacation.? ACHRNEWS RSS. BNP Media, 3 Aug. 2015. Web. 05 Aug. 2015. <>.


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