26
IM 738-2
Mechanical Installation:
Post and Rail Mounting
Post and Rail Mounting
When mounting by post and rail, run the structural support the
full length of the unit. Locate the structural member at the base
of the unit as shown in Figure 31, assuring the I-beam is well
supported by the structural member.
If resilient material is placed between the unit and the rail,
insert a heavy steel plate between the unit and the resilient
material to distribute the load. Seal cabinet penetrations
(electrical, piping, etc.) properly to protect against moisture
and weather.
Figure 31. Post and rail mounting
Rigging and Handling
Lifting brackets with 2" (51 mm) diameter holes are provided
on the sides of the unit.
Use spreader bars, 96" to 100" (2438 to 2540 mm) wide to
prevent damage to the unit cabinet. Avoid twisting or uneven
lifting of the unit. The cable length from the bracket to the
hook should always be longer than the distance between the
outer lifting points.
If the unit is stored at the construction site for an intermediate
period, take these additional precautions:
1
Support the unit well along the length of the base rail.
2
Level the unit (no twists or uneven ground surface).
3
Provide proper drainage around the unit to prevent flooding
of the equipment.
4
Provide adequate protection from vandalism, mechanical
contact, etc.
5
Securely close the doors.
6
If there are isolation dampers, make sure they are properly
installed and fully closed to prevent the entry of animals
and debris through the supply and return air openings.
7
Cover the supply and return air openings on units without
isolation dampers.
Figure 32 shows an example of the rigging instruction label
shipped with each unit.
Figure 32. Rigging and handling instruction label
CAUTION
The unit must be level side to side
and over the entire length.
Equipment damage can result if the unit is not level.
Table 7: W dimension (Figure 31)
Unit
Dimension W
inches
mm
015C-040C
94
2388
045C-135C
99
2538
" *
W
Maximum recommended width for structural member is 5" (127 mm) to
allow for adequate space for duct connections and electrical entry.
WARNING
Use all lifting points. Improper lifting can cause severe personal
injury and property damage.
CAUTION
Lifting points may not be symmetrical to the center of gravity of
the unit. Ballast or unequal cable lengths may be required.
Unit has either four or six lifting points (four-point shown below).
Rigging cables must be at least as long as distance “A.”
Spreader bars
required
Lift only as indicated
Caution:
Lifting points may not
be symmetrical to center of
gravity of unit. Balast or unequal
cable lengths may be required.
A
