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Put a Filter on It! Keeping Indoor Air Clean

Sep 08, 2022 02:12PM ● By Ann Marie O'Phelan

Mold, pet dander, dust, and fungal spores are all indoor air pollutants that an air conditioner’s filter is designed to catch, while not hindering airflow. The filters also block the contaminants from accumulating on the heating, ventilation, and air conditioning (HVAC) system’s internal components. How do you know if you need a new filter or if it must be cleaned? Your energy bill might go up, allergies might plague you, your home might smell musty, there’s dust near your air vent, or you can’t remember the last time you had it cleaned or when the AC unit was last maintained.  

According to the Centers for Disease Control and Prevention (CDC), most Americans spend 90 percent of their time indoors, so it’s essential to make sure the air is clean. For many people, the risks to health from exposure to indoor air pollution may be just as great or greater than risks from outdoor pollution. This is especially concerning for those who suffer from illnesses such as asthma. 

Generally, a filter should be cleaned or changed every 30-60 days, especially during periods of heavy use. Some filters are reusable and need to be cleaned and washed. Others need to be replaced. The dirt and debris are visible on the filter, and it will look grayish over white, so it’s easy to tell when to change or clean it. 

During regular maintenance service, an HVAC technician will likely check your evaporator coil and clean it as necessary, check to see if the proper amount of refrigerant is in place, test for refrigerant leaks and the refrigerant charge, seal duct leakage, measure airflow, inspect terminals and connections, oil motors, check belts, check the accuracy of the thermostat, and sometimes more. And they’ll also check the filter! 


Ann Marie O’Phelan is a Southwest Florida resident and a regular contributor to TOTI Media. 



If your central air filter shows no signs of grime buildup, you can use the hose attachment from your vacuum cleaner or a handheld vacuum to remove any debris. If the vacuum hose doesn’t remove the buildup, you will need to wash it. For a deeper cleaning, fill a sink with one part water and one part white vinegar, and then allow your HVAC filter to soak in the solution for one hour. Rinse it off with fresh water and let it fully dry before returning it to your AC unit.  —Home Depot 


Replacing a dirty, clogged filter with a clean one can lower your air conditioner’s energy consumption by 5 to 15 percent. The average energy bill in Florida per month is $128.08 (2020), and so keeping the filter clean can help cut costs. —U.S. Department of Energy  


A clean filter doesn’t just help the air itself, but it also prevents the evaporator coil from getting dirty so quickly. Energy efficiency is degraded by about five percent each year as the coils get dirtier.  —Florida Public Service Commission