474737 • XRUD and XRUB, Rev. 11, November 2018
2018 © Accurex, LLC
12
Our Commitment
As a result of our commitment to continuous improvement, Accurex reserves the right to change specifications
without notice.
Product warranties can be found online at accurex.com, either on the specific product page or in the Warranty
section of the website at Accurex.com/Resources/Warranty.
Our Commitment
P.O. Box 410 Schofield, WI 54476
Phone: 800.333.1400 • Fax: 715.241.6191
Parts: 800.355.5354 • accurex.com
PROBLEM
CAUSE
CORRECTIVE ACTION
Excessive
noise
or 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, Figures 14 and 15. 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.
Belts too tight or too loose
Adjust tension, see page 8, Figures 17a and 17b.
Wheel improperly aligned and rubbing
Center wheel on inlet, see page 7, Figure 12.
Loose drive or motor pulleys
Align and tighten. See “Pre-Starting Checks”, pages 7 and 8.
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 fasteners to secure the motor hood.
Defective or loose motor bearings
Replace motor with same frame size, RPM-HP
High
horsepower
Fan
Check rotation of wheel, see page 7, Figure 13. Reduce fan speed.
Duct system
Resize ductwork. Check proper operation of face and bypass dampers.
Check filters and access doors.
Fan does
not operate
Electrical supply
Check fuses/circuit breakers. Check for switches off. Check for correct supply voltage.
Drive
Check for broken belts. Tighten loose pulleys or belts.
Motor
Ensure motor is correct horsepower and not tripping overload protector.
Motor
overloads
or 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 pages 7 and 8.
Over/Under line voltage
Contact power company.
Incorrect wheel rotation
Check motor wiring, see page 4, Figure 6. Confirm wheel rotation, see page 7, Figure 13.
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: Proper operation of backdraft or control dampers, obstruction in
ductwork, clean dirty filters.
Unit running backwards
Correct as shown see page 7, Figure 13.
Excessive dirt buildup on wheels
Clean wheel, see page 7.
Improper wheel alignment
Center wheel on inlet, see “Pre-Starting Checks”.
Dampers closed
Inspect and repair.
Blocked duct/clogged filter
Clean or replace.
Belt slippage
Replace and adjust tension.
Speed too slow
Check for correct drives.
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
