8. Troubleshooting
WARNING: Turn off the power supply before performing any operations.
Do not allow the pump or motor to run when dry even for a short period
Strictly follow the user instructions and if necessary contact an authorised service centre
PROBLEM
PROBABLE CAUSES
1) The motor
1a) Unsuitable power supply
does not
1b) Incorrect
start
connections
1c) Engine overload protective
device cuts in.
1d) Blown or defective fuses
1e) Shaft blocked
1f) If the above causes have
already been checked, the
motor may be malfunctioning
2) Pump
2a) Presence of solid bodies in
blocked
the pump rotor
2b) Bearings blocked
3)The pump
3a) Check that the valves are open
functions
and not blocked
but no water
3b) Suction valve closed
comes out
3c) Pump suction filter obstructed
3d) Pump installed above the
surface of the liquid (dry
functioning)
3e) Direction of rotation incorrect
4) Insufficient
4a) Pipes and accessories with
flow
diameter too small causing
excessive loss of head
4b) Presence of deposits or solid
bodies in the internal passages
of the rotor and/or in the diffusers
4c) Rotors deteriorated
4d) Worn rotors and diffusers
4e) Excessive lowering of the
dynamic level of the well
4f) Incorrect direction of rotation
4g) Leaking from delivery pipe
4h) Presence of dissolved gases
in the water
5) Noise and
5a) Rotating part unbalanced
vibrations
5b) Worn bearings
from the
5c) Pump and pipes not firmly attached
pump
5d) Flow too strong for the
diameter of the delivery pipe
5e) Unbalanced power supply
6) Leakage
6a) The
from the
functioned when dry or has stuck
mechanical
6b) Mechanical seal scored by
seal
presence of abrasive parts in
the liquid pumped
electrical
mechanical
seal
has
POSSIBLE REMEDIES
1a) Check that the mains frequency and voltage correspond to the
electrical characteristics shown on the indicator plate. Make
sure that the cross section of the cable is compatible with the
length of cable and with the motor power.
1b) Connect the power supply cable to the terminal board correctly.
Check that the thermal overload protection is set correctly (see
data on the motor name-plate) and make sure that the
fuseboard upline of the motor has been properly connected
1c) Check the power supply and make sure that the pump shaft is
turning freely. Check that the thermal overload protection has
been set correctly (see the motor name-plate)
1d) Replace the fuses, check the electric power supply and points
a) and c)
1e) Remove the cause of blockage as indicated in the "Blocked pump"
instruction booklet
1f) Repair or replace the motor by contacting an authorised service
centre
2a) If possible, dismantle the pump casing and remove any solid
foreign bodies inside the rotor, if necessary contact an
authorised service centre
2b) If the bearings are damaged replace them or if necessary
contact an authorised service centre
3a) Dismantle the check valve on the delivery pipe and release the
valve, if necessary replace it.
3b) Open the suction valve
3c) Extract the pump, remove and clean the suction filter and if
necessary replace it.
3d) Increase the depth of installation of the pump as far as
compatible with pump performance. Do the same if the problem
is due to a lowering of the water table
3e) Invert the electrical connections from the motor to the power
supply terminal
4a)Use pipes and accessories suitable for the specific application
4b) Extract the pump and contact an authorised service centre.
4c) To replace the rotors contact an authorised service centre
4d) Contact an authorised service centre to replace the rotors and
the sealing rings of the diffusers, or diffusers themselves if worn
4e) Increase the depth of immersion of the pump as far as
compatible with pump characteristics, reduce the flow
requested by narrowing the suction valve. Pump too big for the
dynamic level of the well
4f) See 2e)
4g) Locate the points in which the delivery pipe is leaking, if located
in the vertical section of the well, extract the pump and repair
the pipe as needed.
4h) Contact an authorised service centre.
5a) Check that no solid bodies are obstructing the rotor
5b) Replace the bearings
5c) Anchor the delivery and suction piping as needed
5d) Use bigger diameters or reduce the pump flow
5e) Check that the mains voltage is correct
In cases 6a), 6b), replace the seal, if necessary contact an
authorised service centre
6a) Make sure that the pump casing is full of liquid and that all the air
has been expelled.
6b) Use a seal suited to the characteristics of the liquid being pumped.
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