Greenheck SFD, SFB, SWB and SWD (455308) - Manual (Page 11)

Centrifugal Utility Fans 11
®
WARNING
Before taking any corrective action, make certain
unit is not capable of operation during repairs.
AVERTISSEMENT
Avant d’entreprendre toute action corrective,
s’assurer que l’appareil ne pourra pas fonctionner
durant les réparations.
Troubleshooting
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 page 4). Replace worn belts or sheaves.
Bearings
Replace defective bearing(s). Lubricate bearings. Tighten collars &
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 Resize ductwork. Access door, filters, grills not installed.
Duct System
Change obstructions in system. Use correction factor to adjust for
temperature/altitude. Resize ductwork. Clean filters/coils. Change fan
speed.*
Static
Pressure
Wrong Duct system has more
or less restriction than
anticipated
Check rotation of wheel. Adjust fan speed.
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 off. 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
Bearing
Lubrication Check for excessive or insufficient grease in the bearing.
Mechanical
Replace damaged bearing. Relieve excessive belt tension. Align
bearings. Check for bent shaft.
* Always check motor amps and compare to nameplate rating. Excessive fan speed may overload the motor
and result in burnout.