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.
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.
| RIGHT |
INSULATEDDECKUNDER | |
| |
| CONDENSERSECTION |
20 |
|
SUPPLY
20 6
RETURN
2TYP.
30
INSULATEDDECKUNDER | |
| COMPRESSORSECTION |
FRONT 8or14
FIGURE 11 - PREDATOR® ROOF CURB DIMENSIONS
2TYP
23 4
26
RETURN
SUPPLY
10
| |
94 | |
| |
FRONT |
FIGURE 12 - SUNLINE™ TO PREDATOR® TRANSITION ROOF CURBS
Unitary Products Group | 15 |
