Your HVAC-System Filtration: Just as Important in Your Commercial Building as It Is at Home

In both commercial and residential settings, one of the most important functions of the HVAC system is air filtration. HVAC-system filtration helps improve indoor air quality by removing particulates and other material that could create musty, unpleasant air; trigger allergies or asthma symptoms; or cause respiratory issues and possibly disease. Filters can remove dust, lint, pollen, mold, fibers, metal or wood particles, microorganisms, and other contaminants before they enter your indoor work and living areas. To maintain the filters’ effectiveness, it’s important to devote maintenance time to keeping your HVAC-system filtration working at its best.

Basic Filtration System Maintenance

The most basic maintenance for your HVAC-system filtration is keeping the filters clean and free of build-up. As filters capture and hold more particulates, they become dirtier and less effective at trapping additional contaminants that come their way. When a filter is dirty enough, it won’t be able to stop additional particulates and, perhaps worse, the material it has already captured may break free and flow into your indoor air.

Dirty filters can also interfere with HVAC system airflow. If this airflow is reduced or blocked, it can damage your HVAC system. Dirty air filters are one of the main causes of HVAC equipment malfunctions and breakdowns.

A simple visual check is usually sufficient to tell whether a filter needs changing. You’ll be able to see dirt and material in the filter medium. For a better inspection, hold the filter up to a light source. If you can’t see light shining through the filter, it’s dirty enough to change.

Check the system’s air filters at least once a month, or more often if your commercial space tends to have greater amounts of contaminants and particulates. If the filter is dirty, change it; if it still seems clear enough to function, replace it and check it again within the next one or two weeks. (Some HVAC filters are reusable, and if that’s the case, make sure you follow the manufacturer’s recommendations for washing a dirty filter.)

Filter Efficiency

When choosing the filters you’re using for HVAC-system filtration applications, pay careful attention to the filter’s efficiency rating. HVAC filters are usually rated on a scale called MERV, or minimum efficiency reporting value. MERV refers to how effectively and efficiently a filter can remove particulates ranging from 0.3 to 10 microns in size.

Standard MERV ratings range from 1 to 16, with higher numbers indicating better filter performance and efficiency.

• MERV 1-4: These filters, sometimes called panel filters, are low-cost but are not very effective at filtration. They are not recommended for commercial applications.
• MERV 6-8: These higher-grade filters are moderately effective, but still don’t filter the smallest of particles. They may be made of pleated cloth to offer more surfaces for particle capture.
• MERV 9-12: These mid- to high-range filters are of high quality and can capture particulates of 1 micron or larger. They can be effective in most commercial or residential settings.
• MERV 13-16: These are the best standard filters available for use in most HVAC systems. They remove particulates of 0.3 microns and larger.HEPA filtration is also available for specialized commercial applications. HEPA, or high-efficiency particulate air, filters can remove almost 100 percent of the particulates and contaminants from your air, including microorganisms, smoke and powders. HEPA filters carry MERV ratings from 17 to 20, but they are most often used in places where indoor air quality is critical, such as medical facilities, computer clean rooms or other sensitive locations.

An important point to keep in mind is that higher-MERV filters tend to be very dense, which means they can impede HVAC-system airflow. Just like a clogged or dirty filter, this can degrade the performance of your heating and cooling systems and cause damage or breakdowns. Consult with your local trusted HVAC contractor to find out which MERV level will work best for you.

Our goal is to help educate our customers about Plumbing, HVACR, Fire Protection and Alarm Systems in Mechanical, Commercial and Residential settings. For more information on HVAC-system filtration and MERV ratings, or to view projects we’ve worked on, visit our website!