Ductwork; Duct Covers; Predator ® Roof Curb Dimensions; Curbs - York PREDATOR DM090 Installation Manual

035-17311-003-A-0704

DUCTWORK

Ductwork should be designed and sized according to the
methods in Manual D of the Air Conditioning Contractors of
America (ACCA) or as recommended by any other recog-
nized authority such as ASHRAE or SMACNA.
A closed return duct system should be used. This will not
preclude use of economizers or outdoor fresh air intake. The
supply and return air duct connections at the unit should be
made with flexible joints to minimize noise.
The supply and return air duct systems should be designed
for the CFM and static pressure requirements of the job. They
should NOT be sized to match the dimensions of the duct
connections on the unit.
Refer to 9 for bottom air duct openings. Refer to Figure 10 for
rear air duct openings.
FIGURE 11 - PREDATOR
FIGURE 12 - SUNLINE™ TO PREDATOR
Unitary Products Group
®
ROOF CURB DIMENSIONS
®
TRANSITION ROOF CURBS

DUCT COVERS

Units are shipped with the side duct openings covered and a
covering over the bottom of the unit. For bottom duct applica-
tion, no duct cover changes are necessary. For side duct
application, remove the side duct covers and install over the
bottom duct openings. The panels removed from the side
duct connections are designed to be reused by securing each
panel to its respective downflow opening. But keep in mind
that the supply panel is installed with the painted surface UP,
facing the heat exchanger, while the return panel is installed
with the painted surface DOWN, facing the downflow duct
opening. The supply panel is secured with the bracket
(already in place from the factory) and two screws. It's a snug
fit for the panel when sliding it between the heat exchanger
and unit bottom, but there is room. The return panel is
secured with four screws.
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