Faults, Causes And Remedies - Wilo FLA Compact Notice De Montage Et De Mise En Service

10 Faults, causes and remedies

Faults, particularly those affecting the pumps or
the control system, should only be remedied by
Wilo's customer service or a specialist company.
Fault
Pump does not start
Pump does not shut down
Switching frequency is too high or
fluttering
Installation and operating instructions Wilo-FLA Compact
Cause
No mains voltage
Main switch "OFF"
Water level in break tank too low, i.e.
low-water level reached (fault only
occurs in test operation)
Low-water signal transmitter is defective
(fault only occurs in test operation)
Shut-off device closed at pressure
sensor/pressure switch
Start-up pressure is set too low
Switch-on/off pressures for pressure
switch are not coordinated
Motor protection has triggered
(fault only occurs in test operation)
Power contactor is defective
Turn-to-turn fault in the motor
Connection pipe between VBH and pump
blocked or shut off
Air in the connection pipe between VBH
and pump
Impellers are blocked
Non-return valve is leaking
Non-return valve is blocked
Gate valve in the system is closed or not
sufficiently open
Flow rate is too high
Shut-off device is closed at pressure
sensor
Switch-off pressure is set too high
Pressure switch or cable are defective
Incorrect direction of rotation of the
motors
Connection pipe between VBH and pump
blocked or shut off
Shut-off device is closed at pressure
switch
Incorrect supply pressure at diaphragm
expansion tank
Valve at diaphragm expansion tank is
closed
Switching difference is set too low
NOTICE!
The general safety instructions must be observed
during any maintenance or repair work. Also fol-
low the installation and operating instructions of
the pumps and the control device!
Remedy
Check the fuses, cables and connections
Switch on the main switch
Check the break tank's inlet valve/supply line
Check and, if necessary, replace the
low-water signal transmitter
Check and open the shut-off device if
necessary
Check the setting and correct it if necessary
Check the setting and correct it if necessary
Check the default values against the pump or
motor data, measure the current values and
correct the setting if necessary. Check the
motor for defects and replace it if necessary
Check it and replace it if necessary
Check and, if necessary, replace the motor or
have it repaired
Check the connection pipe, if necessary,
remove the clogging or open the shut-off
device
Check and shut off the piping and vent the
pumps if necessary
Check the pump and replace it or have it
repaired if necessary
Check and replace the seal or non-return
valve if necessary
Check and remove the blockage or replace
the non-return valve if necessary
Check and open the shut-off device
completely if necessary
Check the pump data and default values and
correct them if necessary
Check and open the shut-off device if
necessary
Check the setting and correct it if necessary
Check pressure switch or cable and replace if
necessary
Check direction of rotation and correct by
changing over phases if necessary
Check the connection pipe, if necessary,
remove the clogging or open the shut-off
device
Check and open the shut-off device if
necessary
Check the supply pressure and correct it if
necessary
Check the valve and open it if necessary
Check the setting and correct it if necessary
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