210.100-IOM (JUL 2021)
Page 25
AcuAir Hygienic Air Units
Installation
Attaching the AcuAir fresh air
intake plenum
The fresh air intake plenum and hoods are shipped as an
assembly on smaller cfm units. The plenums arrive with
one set of hoods unmounted for larger cfm units.
Figure 23: Fresh air intake plenum ready for shipping
Figure 24: Detached intake hoods ready for shipping
The plenums and all hoods are assembled in the factory
before preparing for shipment. Not all of the attachment
screws are installed in hoods that ship unattached.
Figure 25: Fresh air intake plenum and hoods preas-
sembled in the factory
1. For those unit arriving with unattached hoods, reattach
the hoods starting with a hood in the bottom position
first. Use the factory attached hoods as a model and
the existing screw holes to finalize locations.
2. The AcuAir
®
unit is provided with plenum alignment
tabs and attachment clips to assist with correctly
positioning the plenum assembly and holding it in posi-
tion as it is secured to the air unit. See
. The
alignment tabs are installed in the factory.
The attachment brackets are shipped loose along with
cap screws to mount the brackets and bolts for secur-
ing the plenum in the brackets. In preparation for lifting
the plenum into position, mount the two brackets using
the cap screws provided.
3. Before placing the hood in the mounting position, apply
a continuous bead of polyurethane caulking on the face
of each vertical hood flange and across the face of the
top flange.
4. The plenum and hood assembly can be lifted using the
lifting lugs provided on the top if the plenum
5. On the blank wall of the plenum is an access panel.
This panel can be removed to provide access to the
inside of the plenum when attaching it to the fresh air
opening on the AcuAir
®
unit.
6. Apply continuous beads of polyurethane caulking on
the face of the plenum flanges. Ensure the caulking is
on the outside of the factory drilled attachment screw
holes. This caulking prevents rain water from reaching
the attachment screw penetrations after the plenum is
mounted to the AcuAir
®
unit. See the following figure.
Figure 26: Applying caulk to plenum
Fresh Air Plenum Caulking
Factory Drilled
Tapper
Screw Holes
Site Applied Caulk to Seal the
Plenum to the AcuAir Unit
7. Using a crane, lift the plenum with mounted hoods
into position for attaching to the AcuAir
®
unit. The four
alignment tabs are intended to guide the hood into
position horizontally.
8. Position the two inner legs under the plenum into
the two attachment brackets and insert the four bolts
through the brackets and legs. This secures the plenum
in position vertically. The two outer legs must rest
securely on the additional site support.