10 Common Misconceptions about Air Filters


Forced-air heating and cooling is the most common way homes across the US stay comfortable. The air filter is a vital component of this type of HVAC system. You likely have some unresolved questions regarding your home’s air filter you would like the answer to. Consider these 10 common misconceptions about air filters to set the record straight.

  1. Air filters are not just for keeping dust particles off the equipment. While that was the original purpose of HVAC air filters, they have come to serve another important purpose: sift out airborne contaminants for cleaner indoor air.
  2. Air filters need to be cleaned or replaced regularly to remain effective. It’s not unlikely for neglected air filters to be left in place for a year or more. During that time, the filter collects a hefty amount of airborne particles until it becomes completely blocked. This restricts airflow, puts great strain on your equipment and increases your energy bills. Put a stop to this by checking the filter monthly and cleaning or replacing it according to the manufacturer’s instructions when it appears dirty. For the best results, change the filter after no longer than 90 days.
  3. Pet owners need to change the filter more often. Pet hair and dander is a common allergen found all over a pet owner’s home. You may need to change the filter up to twice as often if you have multiple long-haired breeds.
  4. Not all filters are created equal. Some filters only trap large particles that could damage the equipment. Other filters are so efficient that they actually impede airflow. The key is to strike a balance by choosing a mid-efficiency filter rated about 5 to 8 on the Minimum Efficiency Reporting Value (MERV) scale.
  5. High-efficiency filters may require HVAC system modifications. If you insist on installing a high-efficiency filter, a contactor may need to increase the fan output to compensate for the restricted airflow. Even a MERV 8 filter could require this modification if your furnace came with a MERV 4 or lower filter.
  6. Not all filters are the same size. You need a filter with the proper measurements to ensure a snug fit. Bring your old filter with you the first time you replace it to help you make the right selection.
  7. The direction you install the filter makes a difference. Pay attention to the arrow markers. These indicate which way to insert the filter into the slot.
  8. It’s wise to stock up. Buy a whole box of air filters. That way, you have a stockpile available when the time comes to change the filter. It’s easier to keep up on this task if you don’t have to make a trip to the store in order to change the filter.
  9. You can ask an HVAC contractor for help changing the filter. It’s not a silly question. If you don’t know where your HVAC filter is located or how to change it, ask a contractor for help the next time you schedule preventative maintenance. This should take place once in the spring for your air conditioner and once in the fall for your heating equipment.
  10. Air filters trap particles, not odors. If smells are a problem in your home, consider using a portable air cleaner containing a carbon filter to soak up odors and freshen up the space.

It’s clearly important to invest in the right air filter whether you or anyone in your home has allergies or not. To learn more, please contact the professionals at Aire Serv® today. Our 170 US franchise locations allow us to serve customers from coast to coast.