Are all HVAC air filters the same?

No, HVAC air filters are different in quality and dimensions, and some have specs that others don't. In most cases we advise using the filter your HVAC manufacturer suggests pairing with your system.

All filters are classified with MERV ratings, which vary from 1–20. MERV means minimum efficiency reporting value.

A bigger rating means the filter can trap smaller particles. This sounds outstanding, but a filter that stops finer dust can clog more quickly, increasing pressure on your equipment. If your equipment isn’t made to run with this kind of filter, it may reduce airflow and create other troubles.

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

All filters with a MERV ranking of 5 should get the majority of the everyday annoyance, such as pollen, pet dander and dust. Some filters say they can stop mold spores, but we recommend having a professional eliminate mold instead of trying to conceal the trouble with a filter.

Often the packaging shows how regularly your filter should be exchanged. From what we’ve seen, the accordion-style filters last longer, and are worth the additional cost.

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

While you may tempted to use a HEPA filter, know that's like installing a MERV 16 filter in your HVAC system. It’s extremely unlikely your equipment was designed to handle that level of resistance. If you’re troubled by indoor air quality in Miami, think about installing a HEPA-grade air filtration system. This unit works alongside your comfort system.