10
Specifications subject to change without notice.
516 01 3604 04
Fig. 7 — Unit Leveling Tolerances
Step 5 — Field Fabricate Ductwork
Cabinet return-air static pressure (a negative condition)
shall not exceed 0.35 in. wg (87 Pa) with economizer or
0.45 in. wg (112 Pa) without economizer.
For vertical ducted applications, secure all ducts to roof curb
and building structure.
Do not connect ductwork to unit.
Insulate and weatherproof all external ductwork, joints, and
roof openings with counter flashing and mastic in accor
-
dance with applicable codes.
Ducts passing through unconditioned spaces must be insu
-
lated and covered with a vapor barrier.
If a plenum return is used on a vertical unit, the return
should be ducted through the roof deck to comply with ap
-
plicable fire codes.
UNITS WITH ACCESSORY ELECTRIC HEATERS
All installations require a minimum clearance to combustible
surfaces of 1-in. (25 mm) from duct for first 12-in. (305 mm)
away from unit.
Step 6 — Rig and Place Unit
Keep unit upright and do not drop. Spreader bars are re
-
quired. Rollers may be used to move unit across a roof.
When the unit is ready to be rigged and no longer will be lift
-
ed by a fork truck, the wood protector under the basepan
must be removed. Remove 4 screws from each base rail.
Wood protector will drop to the ground. See instructions on
the unit base rails. Level by using unit frame as a reference.
See Table 5 and Fig. 8 for additional information.
Lifting holes are provided in base rails as shown in Fig. 8.
Refer to rigging instructions on unit.
Before setting the unit onto the curb, recheck gasketing on
curb.
Rigging materials under new unit (cardboard or wood) must
be removed PRIOR to placing the unit on the roof curb.
CAUTION
PROPERTY DAMAGE HAZARD
Failure to follow this caution may result in damage to
roofing materials.
Membrane roofs can be cut by sharp sheet metal edges.
Be careful when placing any sheet metal parts on such
roof.
A
B
C
MAXIMUM ALLOWABLE
DIFFERENCE IN. (MM)
A-B
B-C
A-C
0.5 (13)
1.0 (25) 1.0 (25)
CAUTION
UNIT DAMAGE HAZARD
Failure to follow this caution may result in equipment
damage.
All panels must be in place when rigging. Unit is not
designed for handling by fork truck when packaging
is removed.
If using top crate as spreader bar, once unit is set,
carefully lower wooden crate off building roof top to
ground. Ensure that no people or obstructions are below
prior to lowering the crate.
