English
• Always secure the pump against an accidental
restart by disconnecting it from the mains. Take
appropriate safety precautions.
• Always have a second person on hand to ensure
the pump is switched off in an emergency.
• Secure moving parts to prevent injury.
• Unsanctioned changes to the pump are made at
the operator's own risk and release the manufac-
turer from any warranty obligations.
Fault: The unit will not start
1. Electricity supply interrupted, short circuit or
earth fault in the cable or motor windings
• Have the motor and wires checked by a special-
ist and replaced if necessary
2. Fuses, the motor protection switch and/or moni-
toring devices are triggered
• Have a specialist inspect the connections and
correct them as necessary.
• Have the motor protection switches and fuses
installed or adjusted according to the technical
specifications, and reset monitoring equip-
ment.
• Check that the impeller runs freely. If necessary
clean it and ensure it runs freely again
Fault: The unit starts, but the motor protection
switch triggers shortly after commissioning
1. The thermal trigger on the motor protection
switch is incorrectly set
• Have a specialist compare the setting of the
trigger with the technical specifications and
correct it as necessary
2. Increased power consumption due to major volt-
age drop
• Have an electrician check the voltage on each
phase and rewire if necessary
3. Two-phase operation
• Have a specialist inspect the connection and
correct it as necessary
4. Excessive voltage differences on the three phases
• Have a specialist inspect the connection and
the switching system and correct as necessary
5. Incorrect direction of rotation
• Swap the 2 phases of the mains supply
6. Impeller slowed by accumulation, clogging and/or
solid matter, increased current consumption
• Switch off the pump, secure it against being
switched back on again and free the impeller or
clear the suction port
7. The fluid is too dense
• Contact the manufacturer
Fault: Unit is running but not pumping
1. No fluid available
• Open inlet for tank or slide valve
2. Intake blocked
• Clean the supply line, slide valve, suction piece,
suction port or suction strainer
3. Impeller blocked or slowed
• Switch off pump, secure it against being
switched back on again and free the impeller
4. Faulty hose/piping
• Replace defective parts
38
TROUBLESHOOTING AND POSSIBLE SOLUTIONS
5. Intermittent operation
• Check switching system
Fault: The unit runs, but not within the specified
operating parameters
1. Intake blocked
• Clean the supply line, slide valve, suction piece,
suction port or suction strainer
2. Slide valve in the pressure pipe shut
• Fully open the slide valve
3. Impeller blocked or slowed
• Switch off pump, secure it against being
switched back on again and free the impeller
4. Incorrect direction of rotation
• Replace two phases on the mains supply
5. Air in the system
• Check the pipelines, pressure shroud and/or
hydraulics, and vent if necessary
6. Pump pumping against excessive pressure
• Check the slide valve in the pressure pipe and
open it completely if necessary, use a different
impeller, consult the plant
7. Signs of wear
• Replace worn parts
8. Faulty hose/piping
• Replace defective parts
9. Inadmissible levels of gas in the fluid
• Contact the manufacturer
10. Two-phase operation
• Have a specialist inspect the connection and
correct it as necessary
11. Excessive decrease in the water table during
operation
• Check the supply and capacity of the system,
and inspect the level control settings and
functionality
Fault: The unit does not run smoothly and is
noisy
1. Pump is operating in an inadmissible range
• Check the operational data of the pump and
correct if necessary and/or adjust the operating
conditions
2. Suction port, suction strainer and/or impeller
clogged
• Clean the suction port, suction strainer and/or
impeller
3. Impeller stiff
• Switch off pump, secure it against being
switched back on again and free the impeller
4. Inadmissible levels of gas in the fluid
• Contact the manufacturer
5. Two-phase operation
• Have a specialist inspect the connection and
correct it as necessary
6. Incorrect direction of rotation
• Replace two phases on the mains supply
7. Signs of wear
• Replace worn parts
8. Defective motor bearing
• Contact the manufacturer
9. Pump is installed under tension
• Check installation, use expansion joints if
necessary
WILO SE 04/2014 V05 DIN A4