Troubleshooting - Greenheck DFD Series Installation, Operation And Maintenance Manual

Troubleshooting

WARNING
Before taking any corrective action, make certain unit
is not capable of operation during repairs.
Problem
Excessive Noise
Volume Too Low
Volume Too High
Static Pressure Wrong
Excessive Power
Consumption High
Horsepower
Fan Doesn't Operate
Bearings Overheated
Excessive Vibration
Cause
Wheel Rubbing Inlet
V-Belt Drive
Bearings
Wheel Unbalance
Fan
Duct System
Fan
Duct System
Duct system has more
or less restriction than
anticipated
Fan
Duct System
Electrical Supply
Drive
Motor
Lubrication
Mechanical
Belts
System Unbalance
AVERTISSEMENT
Avant d'entreprendre toute action corrective, s'assurer
que l'appareil ne pourra pas fonctionner durant les
réparations.
Corrective Action
Adjust wheel and/or inlet cone. Tighten wheel hub or bearing
collars on shaft.
Tighten sheaves on motor/fan shaft. Adjust belt tension. Align
sheaves properly (see page 9). Replace worn belts or sheaves.
Replace defective bearing(s). Lubricate bearings. Tighten
collars and fasteners.
Clean all dirt off wheel. Check wheel balance, rebalance in-
place if necessary.
Check wheel for correct rotation. Increase fan speed.
See page 4.
Decrease fan speed.
Resize ductwork. Access door, filters, grilles not installed.
Change obstructions in system. Use correction factor to
adjust for temperature/altitude. Resize ductwork. Clean filters/
coils. Change fan speed.
Check rotation of wheel.
Resize ductwork. Check proper operation of face and bypass
dampers. Check filters and access doors.
Check fuses/circuit breakers. Check for switches turned off or
disconnected. Check for correct supply voltage.
Check for broken belts. Tighten loose pulleys.
Assure motor is correct horsepower and not tripping overload
protector.
Check for excessive or insufficient grease in the bearing.
Replace damaged bearing. Relieve excessive belt tension.
Align bearings. Check for bent shaft.
Adjust tightness of belts. Replacement belts should be a
matched set.
Check alignment of shaft, motor and pulleys. Adjustable pitch
pulleys with motors over 15 hp motors are especially prone to
unbalance. Check wheel balance, rebalance if necessary.
Mixed Flow 11