While keeping your air filter cleaned and replaced regularly will help your heating and cooling system operate the way it should, that is not the only benefit of a good air filter. Air filters can also help enhance indoor air quality (IAQ), which is a key component to maintaining your family’s good health. So, performing regular air filter maintenance can help keep both your system and your family happy and healthy.
When it comes to simple or do-it-yourself HVAC maintenance, it doesn’t get any easier than taking care of your air filter. Like we said before, air filters should be cleaned or replaced regularly. As for the impact your air filter has on your home’s IAQ, here is a simple test to determine how efficient your air filter is at removing pollutants, allergens and other harmful particles from your home. Lay your current air filter horizontally, then pour common table salt through the filter. If some or all of the salt passes through the filter, this is a telltale sign that your filter will not slow down or trap other airborne particles of similar size. It may be time for a new filter or time to upgrade to a more efficient one.
So, what types of filters are the most efficient at improving IAQ? The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) uses a rating system called the minimum efficiency reporting value (MERV). MERV ratings for air filters range from from 1 (lowest) to 20 (highest), and is based on how well the filter removes particles and resists airflow and the filter’s projected lifespan.
Three main types of air filters and their MERV ratings:

  • Flat-panel fiberglass. These filters consist of layers of fiberglas fibers and usually carry a rating of 1 to 4. These inexpensive and disposable filters have a medium efficiency rating for collecting larger airborne particles but a lower rating for capturing smaller dust, dander and bacteria particles.
  • Pleated polyester. The pleats allow for more surface area on the filter, which increases its efficiency in capturing smaller air particles and pollutants. Pleated filters normally have a rating of 5 to 13.
  • High-efficiency particulate air (HEPA). HEPA filters – which the Occupational Safety and Health Administration recognizes as the top filter for removing air particles and pollutants – have a rating of 17 to 20. However, their size is a drawback as most residential heating and cooling systems are not built to accommodate HEPA filters. Switching to a HEPA filter will likely mean hiring an HVAC professional to retrofit your furnace.

In the meantime, remember to change your old filter. Check your furnace manual to find out the proper size, remove the old filter and properly dispose of it. After determining the airflow direction, install the new filter.
For more air filter efficiency information or for a fall tune-up, call Sanborn’s today.