Deciphering Furnace Filters

Are you fuddled by the labels on furnace filters?  Do you leave off replacing them regularly because you’d rather not face the aisle of confusing packaging at the hardware store?  You aren’t alone.  Many homeowners and renters have a hard time deciphering the technical jargon on a furnace filter.  However, it’s not a job that can be left undone.

Replacing the filters on your furnace is critical to its long-term health and longevity.  Air conditioner maintenance experts will tell you that dirty filters are often the cause of a system failure.  An inexpensive fiberglass filter only has a lifespan of about a month before it needs to be replaced.  A better quality pleated filter will last for up to three.  You need to learn the basics and get those dirty filters out of your home.

The filter’s job is to trap particles of dust, dirt and debris so they don’t end up in the furnace and/or spewed back into your air.  A dirty, clogged filter allows less and less air to pass through.  That makes your system work harder and puts a strain on its ability to properly recirculate the air in your home.  The following 4 types of furnace filter will probably be available where you buy your filters:

  • HEPA
  • Electrostatic
  • Pleated
  • Active Carbon

HEPA filters are the gold standard for vacuum cleaner filters.  They trap the most and smallest particles of common allergens like dust, pollen and animal dander.  However, they also restrict airflow significantly so they may not work well in your system.

Electrostatic filters are usually permanent filter that use an electric charge to attract and hold onto particles.  Even though they are permanent, they still need to be relieved of their dirt load periodically.  Most can be rinsed or washed clean of dirt.

Pleated filters can be electrostatic or not.  They use an “accordion” design to increase the surface area of each filter.  With more surface area available, more dirt can be trapped.

If you filter is an active carbon filter, it has the ability to absorb fumes and chemicals and their accompanying odors, effectively “cleaning” the air of these substances.  They may be able to remove harmful chemicals like VOCs as well as bad smells.

Ask your heating & air conditioning installation company which one is right for your system.  You don’t have to be embarrassed anymore.  Just ask and we’ll be glad to help you chose the right filter for your furnace.