back to blog

What are Furnace & A/C Filters Made Of?

What’s in a name? What’s in a filter? There are a wide variety of types of filters for your furnace and not all of them are created equal. This post will give you a brief summary about the different kinds so that you know which one is right for you.

Filters are measured by their percentage of ‘arrestance.’ Arrestance deals with the size and amount of the particle the filter can stop or ‘arrest.’ The higher the percentage, the smaller the particle the filter will stop and the better the filter. In typical duct systems, there are three main types of filtration systems: Conventional “Throwaway” Fiberglass, H.E.P.A. and Electronic Air Cleaners.

Conventional “throw-away” fiberglass – these are the most inexpensive and the most common filters that you can buy. They’re the filter you can see through. They stop only 15% of the largest dust particles in the air and have no effect on pollen, micro-organisms, smoke or other similar pollutants. They need to be replaced every month in the winter and summer. These typically cost $10 or less.

H.E.P.A., or Pleated Paper – these filters look like a paper version of drapery pleats and stop up to 45% of the particles in the air. They come in the same size as a fiberglass filter and are available at most hardware/home improvement stores. H.E.P.A. filters give the greatest degree of improvement for the money spent. They run approximately $500-$1000 including their installation and the frame. A replacement filter costs $75-$100. They should be replaced every 1 to 3 months.

Electronic (not electrostatic) – this filter system uses ionizing cells and offers the best results. It has the highest capture rate of up to 95% of all airborne pollutants including bacteria, dust, animal hair, dust mites, mildew, lint, fungus, smoke, cooking grease, mold and viruses. An electronic air filter can pay for itself by increasing energy efficiency and prolonging the life of your system. They also reduce the need to dust furniture. These cells must be removed and cleaned at least once a month with either a hose or in your dishwasher in order to enjoy maximum efficiency and a cleaner home. Installing an electronic filter costs roughly $900-$1500 including labor.

Dirty or clogged filters can decrease the efficiency of  a furnace or air conditioner because the furnace has to work harder to put out the same amount of heated or cooled air. Therefore it is important to change or clean your filters not just for your health and cleanliness of your home but also for the furnace and air conditioner.  If you have any questions about your own filtration system or upgrading it, please contact FLAME!

Contact flame Same Day Guarantee


Save On Your Next Service
Plumbing Services.

10% Off

Expires 12/31/2023
Cozy up to Savings

Up to $2200 Off High Efficiency LENNOX Heating & A/C System

Expires 12/31/23

Diagnostic Fee Waived with Qualifying Repair

Expires 12/31/23
Heating & Cooling System

$500 Off

Expires 12/31/23
Heartland Academy
Learn More

contact us
same day guarantee

Same Day Guarantee

Why Choose Flame Heating, Cooling, Plumbing & Electrical?

Expect Trustworthy Service & Excellent Craftsmanship

  • Same-day services
  • Licensed & insured
  • Free estimates on replacement quotes
  • Upfront & fair pricing
  • Background checked technicians
  • Financing options
  • Military, veteran & senior discounts
  • Responsiveness & respect for the customer's time
  • Expertise in our field