Field Supplied And Installed Actuators; Mixing Box Damper Actuators; Vertical Draw-Thru Units; Stacked Supply Fan, Return Fan And Exhaust Box Sections - Carrier Aero 39MN Series Installation, Start-Up And Service Instructions Manual

NOTE: While adjusting linkage, one damper must be fully
open and the other fully closed. Top and rear dampers are
shipped with both dampers in closed position. Loosen the
swivel on the interconnecting linkage bar and fully open
rear damper, leaving top damper closed. Retighten the
swivel.
Certain damper combinations require that dual actuators or
bellcrank linkages be field-provided when jack shafts are 90
degree opposed. This may occur when there is a combination
of end dampers with either top or bottom dampers.
FIELD SUPPLIED AND INSTALLED ACTUATORS —
If one or two actuators are used, they must be mounted to
the outdoor-air damper jackshaft. To properly set the con-
necting linkages, determine the rotation required to open
the outdoor-air damper. Ensure the actuator spring return
fully closes the outdoor-air damper.
If more than 2 actuators are used, they must be installed in
equal numbers on each jackshaft. To properly set these damp-
ers, determine the rotation required for each damper and mount
the actuators so that the spring feature will open the return-air
damper and close the outdoor-air damper. Lock each damper
actuator to the jackshaft. Remove any factory-supplied con-
necting linkage between the outdoor air and return-air damp-
ers. Failure to do so will damage the actuators. No additional
linkages are required for these applications.
Exhaust damper boxes are shipped with dampers in the
closed position.
All damper crankarms have 90 degrees travel from open to
closed. They may be adjusted to suit actuator location.
DO NOT mount damper actuators on the unit panels; actua-
tors are shaft mount only. See Table 27 on page 97 for operat-
ing torque requirements.
Mixing Box Damper Actuators —
ing boxes can be supplied with direct mounted damper
actuators. Refer to Fig. 40 for typical actuator mounting.
Actuators are also available for field installation. See Field
Supplied and Installed Actuators section above for more
information. Refer to Table 27 on page 97 for damper oper-
ating torque.
Fig. 40 — Typical Mixing Box Actuator Mounting
To ensure torque is transmitted equally to both damper sec-
tions, actuator must be connected to the jackshaft that drives
the interconnecting linkage bar. Connection to any other shaft
is not recommended.

Vertical Draw-Thru Units

NOTE: Size 21-61 vertical units that exceed the 108-in.
maximum height or units with a vertical fan shipping split
are shipped with the fan out of its operating position, sepa-
rate from the vertical coil section. See Fig. 41.
move screws before lifting the unit.
The 39M mix-
Stacked Supply Fan, Return Fan and Exhaust
Box Sections
NOTE: Do not remove the fan spring isolator holddown
bolts until the section is installed on the coil section.
1. Rig the fan section using the lifting brackets and place
2. Secure the fan and coil sections together using the sup-
Stacked Units Turning Plenum —
configuration (one or multiple sections stacked on top of one or
multiple sections), the units are typically connected by a turn-
ing plenum (Fig. 43). The upper turning plenum must be sealed
a39-4000 and attached to the lower turning plenum with field-supplied
gasketing and hardware. Suggested closed cell gasketing is
0.25 in. x 1.50 in. (for example, McMaster 8694K94 or
Grainger 6YLW0). Suggested hardware is
screws spaced at a minimum of 12 in. apart. Clearance and en-
gagement holes must be drilled in the field through the base rail
into the top frame rail.
101
The unit is secured to a wooden skid with lag screws. Re-
Fig. 41 — Positioning Fan Section
on Top of Coil Section
it on top of the coil section. See Fig. 41.
plied flat washer, the lock washer and the lock nut onto
the stud. See Fig. 42. Screw the base rail of the top unit
to the top frame rail of the bottom unit.
a39-4247
In a stacked unit
1 / -14 self-drilling
4