
SURFACE MOUNT INSTALLATION PROCEDURE:
The Diffuser is fully assembled from the factory with the exception of the HEPA filter which is shipped separately.
NOTE: These instructions are for surface mounting to a sealed ceiling. Some installations require custom mounting and/or
custom diffusers. In those cases be sure to seal the unit to the ceiling and seal all penetrations through the plenum walls.
Step 1
Carefully remove the unit from the shipping carton and inspect for damage that may have occurred during shipping.
If shipping damage is found, do not install. Call the manufacturer to report damage.
Step 2
Wipe down unit to remove shipping dust and debris.
Step 3
Prepare the ceiling: Cut a rectangular hole in the desired location 1.4" smaller than the nominal size of the diffuser.
For example, cut a 46.6" x 22.6" hole for a 48 x 24 unit. Frame the hole with 2 x 4 wood or equivalent steel studs.
Always measure the units to verify dimensions before making cuts.
Step 4 Using a flat screw driver, release the face frame by rotating the four (4) fasteners a quarter-turn counter clock-
wise. Unhook the safety cables from the filter clips. Set the frame aside.
Step 5 Raise unit into the framed opening until the unit is tight against the ceiling. It is recommended to further support
the unit from above using the tabs welded to the plenum.
Step 6 Secure the unit in the ceiling by
installing self-drilling screws
through the plaster frame into
the opening frame. Alternately,
pre-drill holes and install wood
or sheet metal screws.
Step 7 Install duct work as required. Clean installation debris from the unit and surrounding ceiling.
Step 8 Using approved caulk, seal the outer perimeter of the diffuser to the ceiling. Also seal around the mounting screws
and any other holes made in the diffuser.
Step 9
If applicable, install the HEPA filter per the "Removal and Replacement of the HEPA Filter with Gel Seal" on page 6.
Step 10 Wait at least 30 minutes after filter install and ensure there is a positive pressure in the room before performing
any challenge leak testing.
Step 11 Raise the face frame back into place, re-attach the safety chains, and secure quarter-turn fasteners.
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Nailor Industries Inc. reserves the right to change any information concerning product or specification without notice or obligation.