Pre filter on external wall of ducting in AutoCAD, dwg file
<p>This Architectural Drawing is AutoCAD 2d drawing of Pre filter on external wall of ducting in AutoCAD, dwg file. Pre-filters are <strong>used in conjunction with secondary filters and give your HVAC system an advantage over a system without them</strong>. The job of a pre-filter is to protect the secondary filter by capturing the larger dust particles, giving longevity to the more expensive secondary and final filters.</p>