16
Malfunction Remedy
Possible causes
Remedy
Fan air output too low
Incorrect connection wiring (e.g. star instead
of delta.e.g. star instead of delta).
Check connection wiring and correct if
necessary.
Pressure losses too high.
Optimise duct routing.
Volume flow controllers are not or only
partially open.
Check opening position on site.
Inlet or pressure paths blocked.
Remove blockage.
Grinding noises when
starting or operating the
fan
Check whether the duct connections on the
fan are strained.
Loosen duct connections and realign.
Thermal contact/ PTC
thermistor tripped
Direction of rotation of impeller incorrect
Change direction of rotation if
possible. Otherwise contact Walpol.
Missing phase
If using a 3-phase motor (no EC),
check that all 3 phases are present.
Motor overheating
Check impeller cooling (if present),
check resistance of motor windings (if
possible) / contact Walpol.
Capacitor (if used) not or not correctly
connected
Connect capacitor correctly.
Motor blocked
Contact Walpol
Fan does not reach
nominal speed
Defective motor winding
Contact Walpol
Drive motor misaligned
Contact Walpol
Control devices (if used), such as frequency
converter or transformer, are set incorrectly.
Set control devices correctly.
Mechanical blockage
Remove blockage.
Motor does not rotate
Incorrect supply voltage
Check supply voltage, restore power
supply.
Connection defective
Disconnect from power supply,
correct connection according to wiring
diagram
Temperature monitor has reacted.
Let motor cool down. Identify and
rectify cause of fault.
Electronics/motor
overheated
Cooling insufficient
Improve cooling.
Motor overload
Check whether the correct fan is used
for the application.
Ambient temperature too high
Check whether the correct fan is used
for the application.
12.3. Maintenance
The warranty is only valid if maintenance has been carried out correctly and written proof of this has been provided.
To ensure continuous fan operation, we recommend regular maintenance intervals. These maintenance intervals are spe-
cified in the "Activities" table below. In addition, follow-up activities such as cleaning, replacement of defective components
