RFHA SERIES

Application:

The RFHA Series is a combination of two styles of filter frames to provide a modular two-stage filtration system. The RFH HEPA Holding Frame that is designed to hold a gasketed HEPA filter is connected via the HEPA clamp to RFA Universal Holding Frame designed to hold a 2” pleated pre-filter. This combination two-stage modular frame system can be part of a built-up filter bank on the job site or in OEM factory-produced air handling units.

Filter banks may be constructed for upstream (air entering) service or downstream (air leaving) service. To facilitate ease of change-out for the technicians, allow 36 in. for upstream and downstream servicing. Proper seal of the HEPA Frame is achieved by applying a maximum of 20 in. lbs. of torque to each filter with the use of 4 locking clamps, included with each frame. Pressure application should be uniform across the filter, tightening screws in alternating order. If this is done and all joints are carefully caulked, the frames will provide an excellent holding mechanism and leak-free seal for gasketed HEPA filters while also holding the pre-filter adapter frames.

Construction:

The RFH HEPA Frame is constructed of 14 gauge steel while the RFA Universal Pre-filter Frame is constructed of 16 gauge steel. Panel edges are deburred before final assembly for safe handling during installation. Welds are continuous, non-skip welds, to eliminate air bypass and entrapment of contaminants. Corners are mitered and welded in a precision jig to assure squareness and a solid filter fit. All welds are ground smooth and coated with a zinc-rich compound.

Factory-punched .250 in. diameter holes on the top and one side are to be used to join frames at the job site, and .250 in. diameter holes x .375 in. elongated holes are punched on the bottom and other side to assist the installation process. The filter is positioned properly in the frame by filter-centering ridges welded to the inside of the frame on the bottom and both sides. This is important to allow the filter to be centered and mate exactly with the peripheral sealing flange. This ensures an airtight filter-to-frame seal.