Inlet Guide Vane Actuators, Forward-Curved Fans; Position Actuator; Check Linear Actuator Linkage; Direct-Coupled Actuator Installation - Carrier 39T Installation, Start-Up And Service Instructions Manual

Inlet Guide Vane Actuators, Forward-Curved
Fans —
Inlet guide vanes (IGVs) are available as options
on forward-curved fans. They must be adjusted in the field
as follows.
POSITION ACTUATOR — The interconnecting linkage
between the two vane assemblies is factory supplied. The
actuator and mounting brackets are field-supplied. For linear
actuators, mount the actuator to the scroll A-frame or side
plate as shown in Fig. 29. For direct-coupled actuators
(jackshaft-mounted) such as those supplied with the Air Man-
ager Direct Digital Controls, mount the actuator(s) as shown
in Fig. 30 and 31.
CHECK LINEAR ACTUATOR LINKAGE — Linkage ad-
justment holes are provided in the actuator crankarm; adjust
the actuator and linkage for the proper jackshaft rotation listed
in Table 16. After the linkage travel and jackshaft rotation
are set, verify that both vane assemblies move together from
the fully open to fully closed positions.
Do not force inlet guide vanes past the fully open or
fully closed positions.
Set the vanes at the 45 degree position and make sure the
distance ''L'' (Fig. 29) between the swivel joint and jack-
shaft crankarm is the same for both sides of the fan. The
jackshaft crankarm should be perpendicular to the vane
pushrod.
Figure 29 shows the swivel joint at the 12 o'clock posi-
tion required for top horizontal front and downblast
discharge locations. The swivel must be at the 9 o'clock
position for an upblast front discharge and 3 o'clock for
an upblast rear discharge. Regardless of the swivel joint
position, the jackshaft crankarm and swivel on the left and
right vane assemblies must be in line with each other for
correct operation.
NOTE: When the unit is not operating, vanes may not fully close. This
condition is normal. During unit operation, airflow and pressure dif-
ferential help to control and close the vanes.
Fig. 29 — Inlet Guide Vane Linkage Adjustment —
Forward-Curved Fan (Vanes at 45° Position)

DIRECT-COUPLED ACTUATOR INSTALLATION

1. Disconnect power to the fan motor prior to performing
the installation.
2. Open the fan access door and locate the IGV jackshaft.
Measure the IGV jackshaft diameter. Verify that the size
is within the range of the actuator chosen.
3. Loosen the U-bolt locking nuts on the actuator.
4. Slip the actuator over the IGV jackshaft. Align the
actuator parallel with the frame member which supports
the jackshaft.
5. Take the anti-rotation bracket supplied with the actuator
and, with the center locking pin pointed outward, slip
the pin into the slot at the far end of the actuator. Seat
the pin into the center of the groove provided. If the anti-
rotation bracket is not seated against the frame member,
measure the distance from the member and remove the
anti-rotation bracket from the actuator. Bend the bracket
to the required offset. See Fig. 30.
6. With the anti-rotation bracket installed in the actuator
groove, locate the hole in the bracket, closest to the pin,
which is fully in contact against the frame. Mark this
hole location on the frame. Trace the outline of the bracket
on the frame so that it can be re-aligned again when
removed.
7. Remove the bracket and actuator. Drill a pilot hole at
the location marked from Step 6. Install one screw through
the hole. Re-align the bracket with the outline made pre-
viously and tighten the screw.
8. Locate and mark the hole on the opposite end of the
bracket, closest to the pin, which contacts the frame. Drill
a pilot hole in this location and install the remaining screw.
Remove the first screw.
9. Install the actuator on the jackshaft and while mov-
ing into position, adjust the free end of the anti-rotation
bracket so that the pin fully locks into the slot provided
in the actuator. Once the actuator is adjusted into posi-
tion, install the remaining screw into the anti-rotation
bracket. See Fig. 31.
10. Rotate the jackshaft to fully close the IGVs. Press the
release button (BLACK) on the face of the actuator, and
rotate the clamp in the same direction that closed the
IGVs, until the actuator stop is reached. With the
release still pressed, rotate the actuator clamp back 0.1
from the full closed position and release the actuator re-
lease button. Lock the U-bolt clamp into position to se-
cure the actuator to the IGV jackshaft.
CRANKARM
JACKSHAFT
Fig. 30 — IGV Actuator Bracket Installation
40
ANTI-ROTATION STRAP
INSTALLED (ACTUATOR
NOT SHOWN FOR CLARITY)