Install insulation, cant strips, roofing felt, and counter flashing as
shown. Ductwork must be attached to curb and not to the unit. The
accessory thru-the-base power connection package must be in-
stalled before the unit is set on the roof curb.
If electric and control wiring is to be routed through the basepan,
remove knockouts in basepan located in control box area of access
panel; see Fig. 2, 7, or 12 for basepan knockout locations. Attach
the service connections to the basepans.
SLAB MOUNT (HORIZONTAL UNITS ONLY)
Provide a level concrete slab that extends a minimum of 6-in.
(150 mm) beyond unit cabinet. Install a gravel apron in front of
condenser coil air inlet to prevent grass and foliage from obstruct-
ing airflow.
NOTE: Horizontal units may be installed on a roof curb if
required.
A
B
Fig. 18 — Unit Leveling Tolerances
ALTERNATE UNIT SUPPORT (IN LIEU OF CURB OR
SLAB MOUNT)
A non-combustible sleeper rail can be used in the unit curb sup-
port area. If sleeper rails cannot be used, support the long sides of
the unit with a minimum of 4 equally spaced 4-in. x 4-in. (102 mm
x 102 mm) pads on each side. Locate pads so that they support the
rails. Make sure to avoid the fork openings.
20
C
MAXIMUM ALLOWABLE
DIFFERENCE IN. (MM)
A-B
B-C
A-C
0.25 (6)
0.5 (12)
0.5 (12)