Daikin Skyline OAH003GDAC, Installation And Maintenance Manual

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IM 777-18 • SKYLINE OUTDOOR AIR HANDLER 6 www.DaikinApplied.com
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Curb Mounting and Unit Leveling
Do not place a Skyline unit over an open curb unless it is
equipped with a curb-ready base. Installation instructions for
mounting units on a roof curb are provided in IM 770 . For a
copy, contact your local Daikin representative or visit www.
DaikinApplied.com . Make provisions under the unit to divert
any moisture from entering the building below.
For units without roof curb mounting, place the equipment on a
flat and level surface. Where surface irregularities exist, shim
the base of the unit at one or more points along the length of the
rails to prevent distortion or sagging of the support rails. Uneven
or distorted sections cause misfit or binding of the doors and
panels and improper draining of drain pans ( Figure 5 ).
If the unit is supported on rails they must be placed around
the entire perimeter. Additional Supports must be placed
perpendicular to airflow spanning the full width of the unit at
all shipping splits. If the unit is over 107" wide these supports
must also be placed at the entering and leaving edges of fan
and cooling coil sections. The perimeter rails must be at least 2"
wide at the top and capable of carrying the entire weight of the
unit. The cross supports must be 4" wide at the top and capable
of carrying the weight of the two sections it spans. The cross
supports shall be placed such that 2" of the top is supporting
each section. The perimeter rails shall be placed so that they are
fully supporting the outer 2" of the unit. If shims are required they
must be placed such that the unit is fully supported.
Figure 5: Leveling the Unit
Assembling Sections
If the unit is shipped in more than one shipping section, rig
each section into position separately. Shipping sections are
provided with a connection splice joint attached to the cabinet
which seals against the gasket of the frame channel on the
adjoining shipping section. The splice joint provides an air
seal between two sections once they are assembled together.
Some unit configurations require multiple splice joints on the
same face or on opposing faces of a single section. Confirm
correct placement and orientation of unit sections and splice
joints based on included unit drawings. Align all splice joints to
seat into the mating gasket to provide an air seal. If the splice
joint was bent during shipping or rigging, restore it to its original
position ( Figure 10 ). For high pressure low leakage units,
ensure that the D-gasket is attached to the entering air side
frame channel ( Figure 8 and Figure 11 ).If it dislodged during
shipping, restore it to its designed position. Note: Some sections
are shipped with shipping braces.These need to be removed
before connecting the shipping sections. (Figure 6)
Figure 6: Shipping Braces
Shipping Sections
IMPORTANT
The factory supplied D gasket must be field installed prior to
pulling ship sections together. Install D gasket at all section
splits on the mating face of the base rail in an arc shape with
the ends lower than the center, so that any moisture that may
reach the gasket will be drained to the outside of the unit.
( Figure 8 ).
1. Add a lubricant to top of curb gasket to allow sections to
slide together easier.
2. Apply a minimum 1/4" bead of caulk to the mating faces
of frame channels and roof panels at all section splits
of the unit before joining the sections together. Also
adhere the factory supplied, field installed “D” Gasket to
the mating face of the base rail at all section splits in the
shape of an arc to divert any moisture to the outside of
the unit. ( Figure 6 ).