COOK UCIC - Manual (Page 8)

8
Troubleshooting
Problem and Potential Cause
Low Capacity or Pressure
•Incorrect direction of rotation. Make sure the fan rotates in same
direction as the arrows on the motor or belt drive assembly.
•Poor fan inlet conditions. There should be a straight clear duct at
the inlet.
•Improper wheel alignment.
Excessive Vibration and Noise
•Damaged or unbalanced wheel.
•Belts too loose; worn or oily belts.
•Speed too high.
•Incorrect direction of rotation. Make sure the fan rotates in same
direction as the arrows on the motor or belt drive assembly.
•Bearings need lubrication or replacement.
•Fan surge or incorrect inlet or outlet conditions.
Overheated Motor
•Motor improperly wired.
•Incorrect direction of rotation. Make sure the fan rotates in same
direction as the arrows on the motor or belt drive assembly.
•Cooling air diverted or blocked.
•Improper inlet clearance.
•Incorrect fan RPMs.
•Incorrect voltage.
Overheated Bearings
•Improper bearing lubrication
•Excessive belt tension.
UCIC Bearing Replacement
a. Remove windband and damper assembly.
b. Remove fan from curb, then lay the fan on its side to
allow access to the underside.
c. Loosen and remove belts by lowering the motor slide
base with the four adjusting nuts.
d. Remove the discharge cover by removing the attach-
ing bolts around the perimeter of the inner drum (dis-
charge end of unit). Do not remove fan sheave yet.
e. Remove inlet cone by removing attaching bolts
around the perimeter of the inlet cone.
f. Remove wheel by loosening setscrews and sliding off
shaft.
g. Record the location of the fan sheave from end of
shaft, and remove the sheave.
h. Record the distance from either bearing to the end of
the shaft.
i. Loosen setscrews on Bearings and remove shaft.
j. Mark setscrew location on shaft and smooth down any
raised shaft material as required.
k. Remove bearings from bearing base and replace with
new ones, noting the exact location of each; Do not
fully tighten base bolts.
l. Slide shaft though bearings until shaft protrudes the
same amount as measured above. Tapping the inner
race of each bearing with a soft driver may be
required. NOTICE! Do not hammer the end of the
shaft or the bearing housing.
m. Return setscrews to same location as marked above
and tighten one setscrew on each bearing to half its
specified torque.
n. Rotate the shaft to allow the bearings to align them-
selves.
o. Install wheel and inlet cone to their proper location per
wheel-to-inlet clearance section on page 3.
p. Tighten hold-down bolts to proper torque.
q. Turn the shaft by hand. Resistance should be the
same as it was before hold-down bolts were fully tight-
ened.
r. Tighten all bearing setscrews to full specified torque.
s. Replace the sheave, align with motor sheave, and
adjust the belt tension.
t. Replace unit on curb and reconnect power.
u. Test run fan and retighten all setscrews and bolts, and
trim balance as necessary (.0785 in/sec max.).
v. Replace discharge cover.
w. Replace windband and damper assembly.
After 24 hours of operation, retighten all setscrews and
bolts to the appropriate torque.