Troubleshooting And Repairs - Multifan 130 Installation Instructions Operating Instructions

Galvanized Box Fan 130
Illustration 23: V-belt tension check
Adjusting the V-belt tension
The V-belt tension in this fan can be adjusted by adjusting the mounting
position of the motor.
Illustration 24:
Fault
Airflow too high
Airflow too low
Excessive vibration
Fan does not start
Fan does not start
(supply voltage at fan motor terminals is present)
Fan motor overheats while running
INS00025-A Original instructions
1. Loosen the bolts (1)
2. Tighten the bolts (2) until the required V-belt tension has been reached
3. Fasten the bolts (1) again
Capacitor (1~ fan motor)
Capacitor capacitance decreases slowly over time. Average lifespan is ±
30.000 hours. Replace the capacitor when the capacitance has dropped
below the value as listed on the capacitor.
Start capacitor (1~ fan motor)
The start capacitors' lifespan is 500.000 starts. Replace the start capacitor
when the number of starts has reached 500.000.
The start capacitor cannot be serviced or repaired. The start capacitor must
be replaced if it is not functioning properly anymore.
Louvre shutter
Cleaning the shutter is very important. A dirty shutter will reduce the amount
of air moved by the fan reducing your fan efficiency. Clean the louvres
carefully to avoid bending or damaging them. Damaged louvres can cause
the shutter to leak.
10
Possible cause
Fan speed (rpm) too high
System resistance lower than specified
System resistance higher than specified
Impeller imbalance -> impeller damaged
Impeller imbalance -> impeller dirty
Bearings damaged or worn
No power supplied to fan
(If present) VFD (Variable Frequency Drive) defect-
ive
Thermal protection activated
(Fan motor has overheated)
Impeller blocked
Only for 1~ fan motors: wrong or defective capacitor Replace capacitor
Temperature too low for bearing grease
Fan overloaded
Fan motor overheated due to dirt in cooling fins.

Troubleshooting and repairs

WARNING
Troubleshooting and repairs must be performed by skilled per-
sons only!
Possible remedy
Check supply voltage and frequency
Reduce fan speed (if fan can be speed controlled)
Choose alternative fan
Choose alternative fan
Lower system resistance
Replace impeller
Clean impeller
Replace bearings
Check all power supplies
Check fuse/circuit breaker
Check the cabling
Switch on controller
Check VFD (refer to VFD manufacturers' instruc-
tions)
Clean motor
Check for overloading of fan system (intake or ex-
haust blocked?)
Check if supply voltage is not too high or too low
Remove blockage
Do not operate fan outside ambient temperature
range as specified on rating plate and technical data
sheet
Check for overloading of fan system (intake or ex-
haust blocked?)
Clean fan motor
ENGLISH | 13