Product Overview

  • All-welded construction for corrosion resistance and rigidity
  • Gel seal for the best protection against bypass leakage
  • Stainless steel locking arm and screw assemblies secure and seal the HEPA filter
  • Factory-drilled alignment holes facilitate field assembly of built-up filter banks

Typical Applications

  • Food and Beverage
  • Healthcare
  • Microelectronics
  • Museums & Historic Storage
  • Pharmaceutical

AAF Flanders A-4 Frames are permanent holding frames for field or OEM assembly of built-up HEPA/ULPA filter banks. Standard sizes include the three widely-used filter face sizes: 24″ x 24″, 24″ x 12″ and 12″ x 24″, as well as less common sizes, such as 24″ x 30″ and undersize versions of the common face sizes. Separate locking arm and screw assemblies are used to retain the nominal 12 in. depth filter casings. The entire assembly will have the same efficiency as the filters themselves without leaks or bypass when the filters and frames are installed as recommended by AAF Flanders.

Superior Design and Construction

A-4 Frames are constructed of all-welded sealing surface and intermittently welded sides of 14 gauge galvanized construction. Factory-drilled alignment holes on each side facilitate positioning of the frames for easy filter bank assembly. Welded to the inside of the frame on the bottom and both sides are alignment bars. These bars position the filter properly so that it will mate with the “knife edge” flange that extends into the gel sealing channel around the periphery of the filter frame. Four stainless steel removable locking arm and screw assemblies are furnished with each frame. They are easily adjusted by hand to hold the filter in place and press the gel seal channel into the knife edge on the frame. The fluid gel seal provides the best protection against bypass leakage between the filter and the frame over the life of the installation.

Installation Considerations

A-4 Frames may be installed for service from the air entering (upstream) side or the air leaving (downstream) side. Filter installation and removal are greatly facilitated if at least 36 inches of service clearance is provided. If the HEPA/ULPA filter bank is arranged for air entering side service, this clearance space may be shared with downstream-serviced ASHRAE-rated prefilters.


For sizes and performance data:

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