17
WILO SE 10/2015
English
10. Faults, causes and remedies
WARNING! Risk of electric shock!
Before any work on the pump, DE-ENERGISE the
pump by turning off the on/off switch and dis-
connecting the electrical supply to the pump, and
prevent unauthorised restarting. The indicator
light being off does not mean that the pump is
de-energised.
It is recommended to the disconnect the plug
rather than the male electrical connector (IPX4
preservation).
Faults
Causes
Remedies
The pump is turning but
there is no output flow
The internal parts are obstructed by
foreign matter
Dismantle the pump and clean it
Obstruction in the suction piping
Clean the entire piping
Air entering via the suction piping
Check for leaks in the entire pipe up to
the pump and seal any leaks found
The pump is not full of water
Prime the pump again by filling it
Suction pressure is too low, and suction
is usually accompanied by cavitation
noise
Too much friction loss on the suction side
or the negative suction head is too great.
Modify the installation accordingly
The pump is rotating in reverse
Contact customer service
The voltage of the power supply to the
pump is too low
Check the voltage of the power supply
The suction strainer is not submerged
Submerge the suction strainer (at least
700 mm).
Ballast the flexible hose piping if necessary
The pump is vibrating
Not fastened tightly to its foundation
Check and fully tighten the nuts on the
anchor bolts
Foreign matter in the pump
Dismantle the pump and clean it
Difficult rotation of the pump
Check that the pump can turn freely
without any abnormal resistance (with
the motor stopped)
Poor electrical connection
Check the electrical connections
The motor is heating up
excessively
Insufficient voltage
Check that the voltage is in accordance
with section 4.3
Pump obstructed by foreign matter
Dismantle the pump and clean it
Ambient temperature greater than
+ 40°C
The motor is designed to function at a
maximum ambient temperature of + 40°C
The pump is not turning
No electrical power
Check the power supply
Pump blocked
Clean the pump
The sensor on the motor protection
switch has tripped
Allow the motor to cool
The motor is faulty
Replace it
The pump is not delivering
adequate pressure
The motor is not turning at its normal
speed (foreign matter, poor power sup-
ply to motor, …)
Dismantle the pump and remedy the
problem
The motor is rotating in reverse
Contact customer service
Wear on the internal parts of the pump
Replace them
The output flow is
irregular
The negative suction head (HA) is not as
required
Review the installation conditions and the
recommendations made in this manual
The diameter of the suction piping is
less than that of the pump
The piping must have the same diameter
as the suction port on the pump
The suction strainer or the suction pip-
ing is partially obstructed
Dismantle and clean
If you cannot remedy the fault, please
contact WILO customer service.
11. Spare parts
All spare parts should be ordered directly from
WILO customer service.
To prevent errors, always quote the data on the
pump’s rating plate when making an order.
The spare parts catalogue is available at: www.
wilo.com.
Subjet to technical modifications!
