Are all HVAC air filters the same?

No, HVAC air filters vary in quality and size, and some have specs that others don't. In most cases we suggest getting the filter your HVAC manufacturer says to pair with your system.

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

A larger ranking demonstrates the filter can grab more miniscule particulates. This sounds great, but a filter that stops finer dirt can clog more rapidly, raising pressure on your equipment. If your unit isn’t designed to function with this type of filter, it could lower airflow and cause other troubles.

Unless you are in a medical facility, you likely don’t have to have a MERV rating higher than 13. In fact, most residential HVAC systems are specifically designed to run with a filter with a MERV ranking lower than 13. Frequently you will discover that decent systems have been designed to work with a MERV level of 8 or 11.

All filters with a MERV rating of 5 should get many daily triggers, like pollen, pet dander and dust. Some filters say they can trap mold spores, but we recommend having a professional eliminate mold instead of trying to hide the issue with a filter.

Sometimes the packaging shows how regularly your filter should be exchanged. From what we’ve seen, the accordion-style filters hold up better, and are worth the added expense.

Filters are created from differing materials, with one-use fiberglass filters being the most common. Polyester and pleated filters grab more dirt but may decrease your unit’s airflow. Then there are HEPA (high efficiency particulate air) filters.

While you could tempted to use a HEPA filter, know that's like adding a MERV 16 filter in your heating and cooling system. It’s extremely unlikely your system was made to work with amount of resistance. If you’re concerned about indoor air quality in Indianapolis, consider adding a HEPA-grade air filtration system. This unit works in tandem with your heating and cooling system.