Wheel-to-inlet, Troubleshooting, Wheel-to-inlet clearance – COOK AC User Manual
Page 6

6
Recommended Puller:
Lisle No. 45000 Sterling Wheel Puller. This puller is available
at most automotive parts retail outlets.
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 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 bearing bolts and
set screws which will allow
for correct repositioning.
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
13/16”
Above - Drilled hole placement.
Right - Wheel puller.
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.
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.