“No Filter”: Explaining the Types of A/C Filters! - Sun Heating & Cooling, Inc.

“No Filter”: Explaining the Types of A/C Filters!

Types of air filters

Having a clean air filter can save you lots of money on your energy bills! But first, we’ll explain the differences between different types:


This is the type of air filter you’re probably used to seeing most often. It has an “accordion shape” to it. The reason for this accordion is to be able to fit MORE cotton-polyester filtering material onto the same small surface. On top of that larger surface area, usually pleated air filters are denser and able to catch very tiny contaminants like pollen and pet dander.


A HEPA filter is a specific type of pleated filter. It stands for “high-efficiency particulate air.” You’ve probably heard of a HEPA filter before, but maybe weren’t exactly sure of what it is, or what qualifies a filter as a HEPA filter. Any air filter that gets rid of 99.97% or more of particles .3 microns or smaller is considered a HEPA filter. For comparison, the width of a human hair is about 70 microns, meaning that .3 microns is approximately 233 times smaller than a human hair! Wow!

Most people do prefer to use HEPA filters because they are able to catch so many small particles, including most bacteria and viruses. But one small downside to a HEPA filter is that the high density makes air flow more slowly through it. So, especially if you have an old heating and cooling system, you want to be careful that it has a motor powerful enough to push air through a HEPA filter. Otherwise, you could end up damaging your system!

Flat panel filters

Just like the name suggests, flat panel air filters are different from pleated air filters because they are on a flat frame and you won’t see an “accordion.” These filters are cheaper, but pretty much guaranteed to not catch as many particles as pleated types of air filters. We understand why many people would choose this option while on a budget, but we definitely don’t recommend it. You can save money instead with great deals and coupons from Sun!

Call Sun

If you still have any questions about which type of air filter is right for you and your home, or any other questions about your heating and cooling system and its performance, please let us know! We are the premier experts in Oakland County and we’re always happy to help. Contact us online or call now: (248) 986-1506

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