All About HVAC Filters: Types Available Today

When it comes to the daily operations of your home’s HVAC system, few components are more important than your air filter. The HVAC filter serves multiple purposes, from cleaning and purifying your air of any contaminants to ensuring airflow in your entire system is always adequate — and homeowners have some basic responsibilities when it comes to changing or cleaning filters regularly.

At FLAME, we’re here to help with numerous HVAC areas that will keep your system running efficiently, from air duct cleaning and various thermostat services through a number of other areas. We also offer basic expertise and important info on various parts of your system, including your air filters. For those unfamiliar, this two-part blog series will lay out all the basics on these filters — their types and functions, important MERV ratings, and information on the proper size and changing frequency for your air filters. Today’s part one will dig into the various types of air filter you might consider.

Fiberglass/Synthetic Filter

For those looking for an affordable disposable air filter option, fiberglass or synthetic materials are the best option. These are usually made of some combination of cellulose or polyester, combined with a flexible mesh that allows for adequate airflow even when filth builds up on these materials.

Because they’re so affordable and disposable, however, it’s important to be conscious of how frequently you need to change these filters — typically about once every two weeks, though it’s recommended that a new filter be installed every month in order to remove any contaminants that might have built up. As a note of caution, you should avoid using this type of filter in humid climates — the moisture will cause mold and bacteria growth. In addition, for those who want the highest level of contaminant filtration, you may want to look elsewhere.

Polyester Filters

Polyester filters are more expensive than synthetic options, but they also provide superior filtration, typically providing MERV ratings of 7-9 (more on MERV in part two of our series). This is helpful in catching smaller particles like pet dander and hair, but the price point is still affordable enough for homeowners to change these filters as needed — usually about every two months or at least once a season.

Electrostatic Filters

For those specifically looking for allergy filtration, electrostatic filters are the option you’ll want. These fiberglass-surrounded filters activate with the use of an electric charge, which attaches to dirt particles and attracts them to the filter fibers much more effectively than other types. Although only used in about 10 percent of home HVAC units (usually those installed by more expensive custom builders), the MERV rating of electrostatic filters is usually about 12, making them effective at catching even smaller particles than polyester filters.

HEPA Filters

Typically found in commercial buildings rather than homes, HEPA filters — standing for High Efficiency Particulate Air — are a type of electrostatic filter that delivers MERV ratings of 13 or 14. In addition to being ideal for allergy sufferers, these filters effectively trap pollen, dander and other allergens from your air circulation system — making them an option homeowners should consider if you have incredibly sensitive allergies.

For more on the various air filter types you can choose between for your home, or to learn about any of our HVAC services, speak to the staff at FLAME today.