Greenheck Centrifugal (CSW, BIDW, AFDW), Industrial (IPA, IPO, IPW) and Filtered Supply (LSF) (463687) - Manual (Page 11)

11 Centrifugal, Industrial and Filtered Supply
Problem Cause Corrective Action
Excessive Noise
Wheel rubbing (inlet)
Adjust wheel and/or inlet cone.
Tighten wheel hub or bearing collars on shaft.
V-belt drive
Tighten Sheaves on motor/fan shaft. Adjust belt tension. Align
sheaves properly (see V-Belt Drives section). Replace worn belts
or sheaves.
Bearings
Replace defective bearing(s). Lubricate bearings.
Tighten collars and fasteners.
Wheel unbalance
Clean all dirt off wheel. Check wheel balance, rebalance in place
if necessary.
Low CFM
Fan Check wheel for correct rotation. Increase fan speed.*
Duct system See page 3.
High CFM
Fan Decrease fan speed.
Duct system Resize ductwork. Access door, filters, grilles not installed.
Static Pressure
Wrong
Duct system
has more or less
restriction than
anticipated
Change obstructions in system. Use correction factor to adjust
for temperature/altitude. Resize ductwork. Clean filters/coils.
Change fan speed.*
Dirty filters
• Model LSF
Filters need to be cleaned or replaced. To remove the existing
filters, open the top hood panel(s). The filters can now be
removed by lifting them vertically and out of their racking. Be
sure to carefully note the quantity and size of the filters being
removed as some LSF units utilize multiple filters sizes. After the
filters have been cleaned, or new filters are ready to be installed,
place the filters back into the racks in the reverse order of which
they were removed. When all filters are in place, close and
secure the top roof panels.
High Horsepower
Fan Check rotation of wheel. Reduce fan speed.
Duct system
Resize ductwork. Check proper operation of face and bypass
dampers. Check filters and access doors.
Fan Doesn’t Operate
Electrical supply
Check fuses/circuit breakers. Check for switches turned off or
disconnected. Check for correct supply voltage.
Drive Check for broken belts. Tighten loose pulleys.
Motor
Assure motor is correct horsepower and not tripping overload
protector.
Overheated Shaft
Bearing
Lubrication Check for excessive or insufficient grease in the bearings.
Mechanical
Replace damaged bearing. Relieve excessive belt tension. Align
bearings. Check for bent shaft.
Excessive Vibration
Belts
Adjust tightness of belts. Replacement belts should be a
matched set.
System unbalance
Check alignment of shaft, motor and pulleys. Adjustable
pitch pulleys with motors over 15 hp are especially prone to
unbalance. Check wheel balance, rebalance if necessary.
Coupling
misalignment
Check alignment between coupling, motor and fan shafts.
Any adjustments should be made per coupling manufacturer’s
instructions. Shim only under motor.
Troubleshooting
*Always check motor amps and compare to nameplate rating. Excessive fan speed may overload the motor and
result in motor failure. Do not exceed the maximum cataloged RPM of the fan.
NOTE: Always provide the unit model and serial numbers when requesting parts or service information.