AAON RL-240 - Manual (Page 26)

26
For
horizontal return and discharge
applications, total height of mounting rail
and unit base rail must be high enough so
that adequate condensate drain p-trap can be
included. Units require steel mounting rail
support along all four sides of the unit base.
When installed at ground level, a one-piece
concrete slab should be used with footings
that extend below the frost line. Care must
also be taken to protect the coil and fins
from damage due to vandalism or other
causes.
If unit is elevated a field supplied catwalk is
recommended to allow access to unit service
doors.
This unit ships with a curb gasket that is
1¼” wide and 1½” tall. It is recommended
that this or another similar gasket be used
between the curb and the unit to reduce
vibration from the unit to the building.
Duct Connection
Figure 2 - Curb Mounting
Figure 3 - Curb Detail
All roofing work should be performed
by competent roofing contractors to
avoid any possible leakage.
CAUTION
Where the supply or warm air duct
passes through a combustible roof, a
clearance of 1 inch must be
maintained between the outside
edges of the duct and combustible
material in accordance with National
Fire Protection Association Standard
No.
90A. Provide flashings or
enclosure between structure and roof
and all joints must be sealed with
mastic roofing to ensure a watertight
seal.
CAUTION