Are all HVAC air filters the same?

No, HVAC air filters differ in quality and size, and some have features that others don't. In most situations we recommend using the filter your HVAC manufacturer says to pair with your equipment.

All filters are assigned MERV ratings, which go from 1–20. MERV means minimum efficiency reporting value.

A higher ranking means the filter can grab finer particulates. This sounds good, but a filter that catches finer substances can clog faster, increasing pressure on your system. If your system isn’t designed to run with this type of filter, it can reduce airflow and lead to other troubles.

Unless you are in a medical center, you probably don’t have to have a MERV rating greater than 13. In fact, many residential HVAC equipment is specifically designed to run with a filter with a MERV level under 13. Occasionally you will discover that quality systems have been designed to work with a MERV ranking of 8 or 11.

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

Often the packaging demonstrates how frequently your filter should be replaced. In our experience, the accordion-style filters hold up better, and are worth the additional expense.

Filters are manufactured from different materials, with single-use fiberglass filters being the most common. Polyester and pleated filters catch more dirt but may reduce your system’s airflow. Then there are HEPA (high efficiency particulate air) filters.

While you could tempted to use a HEPA filter, keep in mind that's like putting a MERV 16 filter in your heating and cooling system. It’s highly doubtful your equipment was made to work with level of resistance. If you’re worried about indoor air quality. This unit works along with your heating and cooling system.