Troubleshooting – Greenheck USGF (462077) User Manual
Page 10

10
Model USGF Ultimate Steel Grease Fan
®
Troubleshooting
WARNING: Before taking any corrective action, make certain unit is not capable of operation during repairs.
PROBLEM
CAUSE
CORRECTIVE ACTION
Excessive Noise /
Vibration
Wheel rubbing inlet
Adjust wheel and/or inlet cone. Tighten wheel hub or bearing collars
on shaft.
V‑belt drive
Tighten pulleys on motor/fan shaft. Adjust belt tension. Align pulleys
properly, see page 7/figure 15‑16. Replace worn belts or pulleys.
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.
Bad bearings
Replace.
Belts too tight or too loose
Adjust tension, see figure 18.
Wheel improperly aligned and rubbing
Center wheel on inlet, see figure 14.
Loose drive or motor pulleys
Align and tighten. See “Pre‑Starting Checks”, see page 6.
Foreign objects in wheel or housing
Remove objects, check for damage or unbalance.
Fan base not securely anchored
Secure properly.
Motor hood loose and rattling
Tighten acorn nuts securing motor hood.
Defective or loose motor bearings
Replace motor with same frame size, RPM‑HP.
High Horsepower
Fan
Check rotation of wheel, see figure 13. 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.
Motor Overloads /
Overheats
Lubrication
Check for excessive or insufficient grease in the bearing.
Mechanical
Replace damaged bearing. Relieve excessive
belt tension. Align bearings. Check for bent shaft.
Belt slippage
Adjust tension or replace bad belts, see page 7.
Over/Under line voltage
Contact power company.
Incorrect wheel rotation
Check motor wiring, see figure 3.
Wheel RPM too high
Check drives or slow down fan by opening variable pitch pulley on
motor shaft.
Undersized motor
Check motor ratings with catalog speed and air capacity chart.
Motor wired incorrectly
Check motor wiring to wiring diagram located on fan motor.
Reduced Airflow
System resistance too high
Check system for obstruction in ductwork.
Unit running backwards
Correct as shown in figure 13.
Excessive dirt buildup on wheels
Clean wheel.
Improper wheel alignment
Center wheel on inlets, see Pre‑Starting checks and figure 14.
Dampers closed
Inspect and repair.
Blocked duct/clogged filter
Clean or replace.
Belt slippage
Replace and adjust tension.
Speed to slow
Check for correct drives.