Carrier WeatherExpert 48LC Series Installation Instructions Manual page 12

Step 5 — Field Fabricate Ductwork
NOTE: 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.
Fabricate supply ductwork so that the cross sectional dimensions
are equal to or greater than the unit supply duct opening dimen-
sions for the first 18-in. (458 mm) of duct length from the unit
basepan.
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.
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.
"B"
MAX WEIGHT
UNIT
LB
2460
48LC*008
2465
48LC*009
2465
48LC*012
NOTES:
1. Dimensions in ( ) are in millimeters.
2. Hook rigging shackles through holes in base rail, as shown in detail "A." Holes in base rails are centered around the unit center of gravity.
3. Use wooden top to prevent rigging straps from damaging unit.
PLACE ALL SEAL STRIP IN PLACE BEFORE PLACING
UNIT ON ROOF CURB.
914 - 1371
( 36" - 54" )
"C"
"A"
SEE DETAIL "A"
A
KG IN
1116 116
1118 116
1118 116
Fig. 7 — Rigging Details
Step 6 — Rig and Place Unit
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 re-
moved. Remove 4 screws from each base rail. Wood protector will
drop to the ground. See instructions on the unit base rails.
Keep unit upright and do not drop. Spreader bars are not required.
Rollers may be used to move unit across a roof. Level by using
unit frame as a reference. See Table 2 and Fig. 7 for additional in-
formation.
Lifting holes are provided in base rails as shown in Fig. 7. Refer to
rigging instructions on unit.
Rigging materials under unit (cardboard or wood) must be re-
moved PRIOR to placing the unit on the roof curb.
When using the standard side drain connection, ensure the red
plug in the alternate bottom connection is tight. Do this before set-
ting the unit in place. The red plug can be tightened with a
square socket drive extension. For further details, see "Install Ex-
ternal Condensate Trap and Line" on page 18.
Before setting the unit onto the curb, recheck gasketing on 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.
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.
DUCT END
DIMENSIONS
B
MM IN
2945 57
2945 58
2945 58
12
CAUTION
DETAIL "A"
C
MM IN
1448 59.5
1473 59.5
1473 59.5
/ -in.
1
2
MM
1510
1510
1510