Are all HVAC air filters the same?

No, HVAC air filters differ in quality and dimensions, and some have specs that others don't. In most cases we advise using the filter your HVAC manufacturer says to pair with your unit.

All filters are classified with MERV ratings, which range from 1–20. MERV is short for minimum efficiency reporting value.

A higher value means the filter can trap more miniscule particulates. This sounds good, but a filter that stops finer dirt can become obstructed more rapidly, increasing pressure on your system. If your system isn’t created to work with this model of filter, it could reduce airflow and lead to other troubles.

Unless you live in a hospital, you likely don’t have to have a MERV level higher than 13. In fact, many residential HVAC units are specifically engineered to run with a filter with a MERV ranking under 13. Sometimes you will find that quality systems have been designed to work with a MERV rating of 8 or 11.

All filters with a MERV ranking of 5 should catch many daily annoyance, such as pollen, pet dander and dust. Some filters assert they can trap mold spores, but we advise having a professional eliminate mold as opposed to trying to mask the trouble with a filter.

Usually the packaging demonstrates how often your filter should be changed. From what we’ve seen, the accordion-style filters work better, and are worth the added price.

Filters are manufactured from differing materials, with single-use fiberglass filters being standard. Polyester and pleated filters trap more dirt but may limit your unit’s airflow. Then there are HEPA (high efficiency particulate air) filters.

While you may want to use a HEPA filter, know that's like adding a MERV 16 filter in your comfort equipment. It’s highly unrealistic your system was designed to work with level of resistance. If you’re worried about indoor air quality in Hilton Head Island, consider getting a HEPA-grade air filtration system. This equipment works in tandem with your HVAC system.