Are all HVAC air filters the same?

No, HVAC air filters vary in quality and dimensions, and some have specifications that others don't. In most instances we advise getting the filter your HVAC manufacturer says to pair with your system.

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

A higher value means the filter can catch more miniscule particulates. This sounds good, but a filter that catches finer dirt can clog more quickly, increasing pressure on your system. If your equipment isn’t designed to function with this kind of filter, it could reduce airflow and cause other issues.

Unless you are in a hospital, you more than likely don’t require a MERV level greater than 13. In fact, most residential HVAC systems are specifically engineered to work with a filter with a MERV ranking below 13. Frequently you will find that good systems have been designed to run with a MERV level of 8 or 11.

All filters with a MERV rating of 5 should catch most of the common nuisances, such as pollen, pet dander and dust. Some filters assert they can catch mold spores, but we suggest having a professional get rid of mold instead of trying to mask the trouble with a filter.

Often the packaging indicates how frequently your filter should be exchanged. In our experience, the accordion-style filters last longer, and are worth the extra expense.

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

While you might tempted to use a HEPA filter, keep in mind that's like putting a MERV 16 filter in your comfort equipment. It’s highly doubtful your unit was created to work with level of resistance. If you’re worried about indoor air quality in Calgary, consider installing a HEPA-grade air filtration system. This product works along with your comfort system.