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A
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 accordance with ap-
plicable codes.
Ducts passing through unconditioned spaces must be insulated
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 applicable fire codes.
C
MAXIMUM ALLOWABLE
DIFFERENCE IN. (MM)
B
A-B
B-C
0.5 (13)
1.0 (25)
1.0 (25)
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.
UNITS WITH ACCESSORY ELECTRIC HEATERS
All installations require a minimum clearance to combustible sur-
faces of 1 in. (25 mm) from duct for first 12 in. (305 mm) away
from unit.
Step 6 — Rig and Place Unit
A-C
Keep unit upright and do not drop. Spreader bars are required.
Rollers may be used to move unit across a roof. When the unit is
ready to be rigged and no longer will be lifted 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 infor-
mation.
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 re-
moved PRIOR to placing the unit on the roof curb.
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.
10
CAUTION
CAUTION
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