Panel filters are flat, rectangular air filters constructed from woven fiberglass or synthetic media held within cardboard or metal frames. They are the most common filter type in residential HVAC systems, available in standard sizes like 16×25×1 inches and 20×25×4 inches. Panel filters typically carry MERV ratings from 1 to 13, with residential applications most commonly using MERV 8 to 11 ratings.
Construction and Performance
Panel filters use electrostatic or mechanical filtration methods to capture dust particles as air passes through the media. One-inch thick filters require monthly replacement, while 4-inch and 5-inch thick versions last 6 to 12 months. Pressure drops range from 0.08 inches of water column for MERV 8 filters to 0.3 inches for MERV 13 filters at standard airflow rates of 400 CFM per square foot.
Practical Advantages
Panel filters offer affordability and ease of installation, requiring simple frame-to-housing insertion without specialized tools. Their widespread availability in retail stores and online suppliers makes emergency replacements convenient. However, they provide limited dust-holding capacity compared to bag or cartridge filters, necessitating more frequent replacements in high-dust environments or commercial applications.