Your Guide To HVAC Air Filter Ratings

That simple HVAC air filter makes a big difference in your home’s energy costs, indoor air quality (IAQ) and the performance of your HVAC system. Learning the aspects of filters can help you choose the best one for your system to make a positive difference indoors without much of an investment.

The air filter exists to keep the parts inside the air handler clean and running smoothly, but filters are available that do much more, as indicated by their ratings. Filters are assigned a MERV (minimum efficiency reporting value) rating that range between 1–16. Higher ratings indicate that the filter is more effective at trapping and holding smaller airborne particles, like mold spores, pet dander, and dust mite waste.

The inexpensive fiberglass filters have MERV ratings between 1–4, and the pleated filters range from 5–16. Sometimes filter manufacturers don’t display the MERV ratings, but use terms like “good,” “better,” and “best.”

These shortcut terms provide filter quality information, but before upgrading, check your owner’s manual. Sometimes the highest rated filters (MERV 12 and above) can harm your equipment. By their nature, filters slow the airflow through the air handler, and it’s possible for a filter that’s too dense to slow the flow too much.

Too little air flowing through the air handler increases energy bills or prompt a frozen evaporator coil. Too thin an air filter, especially fiberglass, allows small particles to collect inside the air handler and ductwork, both of which lower IAQ.

If your owner’s manual doesn’t prescribe the best filter for your system, ask your trusted HVAC contractor, who can also tell you where, how and when to change it. Most HVAC contractors don’t recommend reusable filters because their MERV rating is low and mold can grow inside their media if they’re not completely dried before using.

The HVAC air filter plays a significant role in your home’s IAQ, energy costs and the HVAC system’s performance. To learn more, contact Jackson & Sons, providing outstanding HVAC services for Eastern North Carolina homeowners.

Our goal is to help educate our customers in Eastern North Carolina (including Wayne, Johnston, Greene, Lenoir, Pitt and Duplin Counties) about energy and home comfort issues (specific to HVAC systems).

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