Are all HVAC air filters the same?

No, HVAC air filters vary in quality and dimensions, and some have specs that others don't. In most situations we advise using the filter your HVAC manufacturer recommends pairing with your equipment.

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

A bigger ranking demonstrates the filter can catch finer substances. This sounds outstanding, but a filter that stops finer dust can clog more rapidly, raising pressure on your unit. If your unit isn’t created to function with this kind of filter, it may decrease airflow and lead to other issues.

Unless you are in a hospital, you likely don’t have to have a MERV ranking greater than 13. In fact, the majority of residential HVAC units are specifically engineered to run with a filter with a MERV ranking below 13. Frequently you will discover that good systems have been designed to run with a MERV rating of 8 or 11.

All filters with a MERV rating of 5 should trap many daily triggers, such as pollen, pet dander and dust. Some filters assert they can catch mold spores, but we suggest having a professional eliminate mold rather than trying to mask the problem with a filter.

Sometimes the packaging demonstrates how often your filter should be exchanged. From what we know, the accordion-style filters last longer, and are worth the extra cost.

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

While you might be interested in using a HEPA filter, remember that's like installing a MERV 16 filter in your comfort equipment. It’s extremely unlikely your system was made to work with amount of resistance. If you’re concerned about indoor air quality in Toronto, think over adding a HEPA-grade air filtration system. This equipment works in tandem with your comfort system.