COOK UCIC - Manual (Page 3)

3
Inlet Duct Turns
For ducted inlets, allow at least 3 fan wheel diameters
between duct turns or elbows and the fan inlet.
Discharge Duct Turns
Where possible, allow 3 duct diameters between duct
turns or elbows and the fan outlet. Refer to the drawing
below.
Wheel-to-Inlet Clearance
The correct wheel-to-inlet clearance is critical to proper
fan performance. This clearance should be verified before
initial start-up since rough handling during shipment could
cause a shift in fan components. Refer to wheel/inlet draw-
ing below for correct overlap.
Adjust the overlap by loosening the wheel hub and mov-
ing the wheel along the shaft to obtain the correct value.
A uniform radial gap (space between the edge of the
cone and the edge of the
inlet) is obtained by loosen-
ing the inlet cone bolts and
repositioning the inlet cone.
Size Overlap
60 - 165 3/16”
180 - 245 1/4”
270- 300 5/16”
330 - 365 3/8”
402 7/16”
445 - 490 1/2”
540 - 730 13/16”
Inlet Duct Turns
Correct
Incorrect
MIN
3 DIA
Discharge Duct Turns
Correct
Incorrect
MIN
3 DIA
Belt and Pulley Installation
Belt tension is determined by the sound the belts make
when the fan is first started. Belts will produce a loud
squeal which dissipates after the fan is operating at full
capacity. If the belt tension is too tight or too loose, lost effi-
ciency and possible damage can occur.
Do not change the pulley pitch diameter to change ten-
sion. This will result in a different fan speed than desired.
a. Loosen motor plate adjustment nuts and move motor
plate in order that the belts can easily slip into the
grooves on the pulleys. Never pry, roll, or force the
belts over the rim of the pulley.
b. Adjust the motor plate until proper tension is reached.
For proper tension, a deflection of approximately 1/4”
per foot of center distance should be obtained by
firmly pressing the belt. Refer to Figure 3.
c. Lock the motor plate adjustment nuts in place.
d. Ensure pulleys are properly aligned. Refer to Figure 4.
Pulley Alignment
Pulley alignment is adjusted by loosening the motor pulley
setscrew and by moving the motor pulley on the motor shaft.
Figure 4 indicates where to measure the allowable gap
for the drive alignment tolerance. All contact points (indi-
cated by WXYZ) are to have a gap less than the tolerance
shown in the table. When the pulleys
are not the same width, the allowable
gap must be adjusted by half of the dif-
ference in width (As shown in A & B of
Figure 4). Figure 5 illustrates using a
carpenter’s square to adjust the posi-
tion of the motor pulley until the belt is
parallel to the longer leg of the square.
1 foot
1/4 inch
Figure 3
Figure 4
Tolerance
Center Distance
Maximum
Gap
Up thru 12” 1/16”
12” up through 48 1/8”
Over 48” 1/4”
OFFSET ANGULAR OFFSET/ANGULAR
A
W
X
Y
Z B
CENTER
DISTANCE
(CD)
GAP GAP
Figure 5