Air Filters: More to Know Than Just When to Change

Air filters for your cooling and heating systems must be clean to work efficiently, but it takes more than regular maintenance to ensure your filters keep your air clean. Understanding all the factors that affect your HVAC filter choice and use helps you get the most out of these important system components.

Efficiency – An air filter’s efficiency is indicated by its MERV (Minimum Efficiency Reporting Value). A higher MERV means a more efficient filter. Disposable fiberglass panel filters (MERV 1-4) do little to clean your air. The minimum you’ll need for cleaner air is a pleated (extended surface) filter with a MERV between 5 and 8. For even greater filtration, choose a pleated or bag filter with a MERV between 9 and 12. For most homes, filters with MERVs of 8 to 11 are ideal.

HEPA filtration – Although true HEPA (High Efficiency Particulate Air) filters aren’t appropriate for most homes, you’ll get very similar results with a filter that has a MERV between 7 and 13. If you experience allergies or asthma symptoms, consider a 12 or 13 MERV filter. In some HVAC systems, a filter with a MERV higher than 11 will interfere with airflow and cause damage, so consult an HVAC technician before installing one.

Size and fit – The best way to get the right size replacement filter is to take your old filter with you when you go shopping. If your new filter doesn’t fit snugly in the frame, debris will pass through any gaps that are left. There’s also a chance the filter will blow out of the frame completely.

Cleaning your filters – If you use a panel, pleated or bag filter, you’ll need to replace the filter regularly. Electrostatic air filters, however, are designed to be cleaned. Every other month, remove the filter and spray down the clean side (opposite the direction of the airflow) to remove debris.

If you’re planning to upgrade your HVAC filters or you’d like professional guidance on improving your home’s air quality, get in touch with us at Energy 1 Heating & Air Conditioning. We provide a full range of HVAC services for homeowners in Lorain, Elyria and Oberlin.

Our goal is to help educate our customers in Lorain, Ohio about energy and home comfort issues (specific to HVAC systems).  For more information about air filters and other HVAC topics, download our free Home Comfort Resource guide.

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