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GQ, GX, GM Rev. 5 - Operating Instructions
GB
PROBLEM
1) The engine
does not
start
2) Pump
blocked
3)The pump
functions
but no water
comes out
4) Insufficient
flow
5) Noise and
vibrations
from the
pump
6) Leakage
from the
mechanical
seal
PROBABLE CAUSES
1a) Unsuitable power supply
1b) Incorrect
electrical
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
engine may be malfunctioning
2a) Presence of solid bodies in
the pump rotor
2b) Bearings blocked
3a) Presence of air inside the
pump or suction tube
3b) Suction filter blocked
4a) Pipes and accessories with
diameter too small causing
excessive loss of head
4b) Presence of deposits or solid
bodies in the internal passages
of the rotor suction filter
4c) Rotor deteriorated
4d) Worn rotor and pump case
4e) Excessive viscosity of the liquid
pumped (if other than water)
4f) Incorrect direction of rotation
5a) Rotating part unbalanced
5b) Worn bearings
5c) Pump and pipes not firmly
attached
5d) Flow too strong for the
diameter of the delivery pipe
5e) Unbalanced power supply
6a) The mechanical seal has
functioned when dry or has
stuck
6b) Mechanical seal scored by
presence of abrasive parts in
the liquid pumped
11. 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
OFF
POSSIBLE REMEDIES
1a) Check that the mains frequency and voltage correspond to the
electrical characteristics shown on the indicator plate
1b) Connect the power supply cable to the terminal board correctly.
Check that the thermal overload protection is set correctly (see
data on the engine indicator plate) and make sure that the
fuseboard upline of the engine 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 engine indicator 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 engine by applying to 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) Release the air from the pump using the pump plugs and/or
using the delivery control valve .Repeat the filling operations
until all air has been expelled
3b) Clean the filter, if necessary, replace it . See point 2b) also.
4a) Use pipes and accessories suitable for the specific application
4b) Clean the rotor and install a suction filter to prevent other
foreign bodies from entering
4c) Replace the rotor, if necessary, contact an authorised service
centre
4d) Replace the rotor and the pump casing
4e) The pump is unsuitable
4f) Invert the electrical connections on the terminal board or control
panel
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 right
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.
Changes reserved.
IST GQ_GX_GM_07_2018R5_MXS 11_03con gall 09/07/18 09:06 Pagina 15
