IMO BKF

Maintenance/troubleshooting/cleaning
14 BKF 16.08.2021
CAUTION
Danger from hot surfaces!
 During maintenance/troubleshooting and cleaning wear protective working gloves to prevent contact
with hot motor!
CAUTION
Danger from cutting edges!
 Wear protective working gloves when cleaning!
10.1 Malfunctions and troubleshooting (generally)
Possible reasons
Action
The ventilator
does not run
Connection to the mains fault.
Thermal protection triggers.
Motor fault.
Check connection to the mains and thermal protection. If
ok. check electric motor (winding resistance, resistance to
ground). If two speed motor (4-6, 6-8, 8-12, 4-8, 6-12) is
installed, check all speed. If necessary get the electric mo-
tor repaired.
Air volume is
too low
Wrong direction of rotation.
Too high pressure drop in system.
Obstacles in duct.
Check the direction of rotation. If wrong, swap the supply
connection of any 2 phases. Check if current is similar all
phases. If ok. check operating point and system design.
Thermal pro-
tection of the
fan switches
off
Short-circuit.
Damage to the bearings.
Impeller blocked or grinding.
Compare connection with wiring diagram. Compare the
data of electric motor with setting of thermal protection.
If ok. check power supply and electric motor. Get the
electric motor or if necessary the complete fan repaired.
Overcurrent
Check the direction of rotation. If wrong, swap any 2
phases. Check if current is similar all phases.
Noise
Damage to the bearings.
Impeller blocked or grinding.
Get the electric motor or if necessary the complete fan re-
paired.
Loose fit on the base plate or mo-
tor support.
Tighten the bolts, look for the cause of vibrations.
Vibrations
The actual pressure drop of the
system is higher than supposed,
the fan could operate in an unsta-
ble area of the fan curve.
Check operating point and system design. Consult cus-
tomer service of the manufacturer.
Damage or dust layer on impeller.
Clean the impeller, if necessary balance it or replace it.
If the reason for malfunction cannot be clearly determined, consult the customer service of manufacturer.
10.2 Cleaning
Regular cleaning prevents unbalance.
Keep casing and impeller clean and clean them if necessary with a brush (do not use a steel brush or high-pres-
sure cleaner). Do not use any detergents for interior cleaning. To get to impeller unscrew cover of revision
opening (see Appendix 1).
10.3 Maintenance, service
Basically the fan may be repaired at the manufacturer only! Exceptions are non-relevant components. For further in-
structions consult the manufacturer.