Daikin Skyline OAH003GDAC, Installation And Maintenance Manual

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www.DaikinApplied.com 17 IM 777-18 • SKYLINE OUTDOOR AIR HANDLER
Dampers and Hoods
Side dampers may be provided in the mixing box and
economizer sections of units. When dampers are provided,
access to the damper drive shaft is recommended internally
through the upstream or downstream sections of the unit. If no
internal access is available, a removable panel is located above
the weather hood to provide access to the damper drive shaft.
NOTE: The hood and damper must be removed to remove
the panel. Other access may be available depending
on the specific construction of the unit ( Figure 36 ).
Figure 37: Filler Panel Over the Weather Hood
When units are ordered with exhaust hoods and intake hoods
adjacent to each other, install a field-supplied barrier to prevent
recirculation of exhaust air into the intake openings. ( Figure
37 ).
Figure 38: Field-Installed Barrier Between Hoods
Mounting Actuators
CAUTION
Maximum damper rotation is 70°. Maximum shaft torque is
205 inches/pound. Greater rotation or torque can cause
equipment damage.
The installing contractor is responsible for the mounting of
all field-installed actuators. No provisions are made for the
location of these actuators due to the number of options and
arrangements available and the variety of specific applications.
Typically, actuators are mounted inside the cabinet. Provide
proper support for the actuator to avoid excessive stress in the
cabinet, linkage, or damper shafts.
EXCEPTION: For the angled economizer, the fresh air
and return air dampers must always be driven by separate
actuators.
NOTE: Damper blades are at full flow when open to 70
degrees. Do not open blades further than 70 degrees.
Fresh air and return air dampers can be linked together and
driven from the same actuator if the dampers are the same
size. If the dampers are different sizes, they must be driven
by separate actuators and controlled appropriately. Exhaust
dampers are always driven by a separate actuator.
A typical rotary electric actuator can handle up to 40 sq. ft. of
damper. For pneumatic actuators, allow 5 in-lb per square foot
of damper area.
Angled Economizer Actuator
Access
Access to the fresh air and exhaust air damper drive shafts
of the angled economizer is recommended internally through
the upstream or downstream sections of the unit. If no internal
access is available, a removable filler panel is located above
the weather hood to provide access to the damper drive shaft.
NOTE: The hood and damper must be removed to remove
the panel. ( Figure 36 ) There are two options for
gaining access to the return air damper drive shaft:
1. If the unit has a housed return fan or plenum exhaust
fan, an access section should be located immediately
downstream of the economizer section for access to the
return air damper drive shaft.
2. If the unit has a plenum return fan or housed exhaust
fan, access to the return air damper drive shaft can
be obtained via the fan section’s access door and the
removable filler panel located above the return air damper.
Roof Cap
Drip Edge
Filler Panel
Damper
Hood
Remove Screws and
Filler Panel to Access
Damper Control Shaft