9
8 . OPERATING TROUBLE :
Switch the pump OFF before doing any work on it
ATTENTION !
TROUBLES
8.1 THE PUMP TURNS BUT NO
DELIVERY
8.2 THE PUMP VIBRATES
8.3 THE PUMP OVERHEATS
8.4 THE MOTOR DOESN’T
RUN
8.5 THE PUMP DELIVERS
INSUFFICIENT PRESSURE
8.6 THE MOTOR TRIPS OUT
8.7 THE FLOW IS IRREGULAR
CAUSES
a) The internal parts are obstructed by
foreign bodies:
b) Suction pipe obstructed:
c) Air leaks in via suction pipe:
d) The pump has lost its priming:
e) The suction pressure is too low; this is
generally accompanied by cavitation
noise.
f) The pump turns the wrong way (three-
phase motor):
g) The supply voltage to the motor is too
low:
h) The strainer isn’t immersed :
a Loose on its foundation:
b) Foreign bodies obstructing the pump:
c) Pump is hard to turn:
d) Incorrect electrical connection:
a) Voltage too low:
b) Foreign bodies obstructing the pump:
c) Ambient temperature above +40°C:
a) No current:
b) Hydraulic part blocked:
c) Thermal sensor release (1-phase):
a) The motor fails to run at its normal
speed (foreign bodies, defective
power supply, etc.)
b) The motor is faulty:
c) Pump poorly filled:
d) The motor turns the wrong way (three-
phase motor):
e) Internal components wear:
a) The setting of the thermal relay is too
low (three-phase motor):
b) The voltage is too low:
c) One phase is open-circuit:
d) The thermal relay of the circuit-breaker
is faulty:
e) The motor is faulty:
a) The suction height (SH) is exceeded:
b) The diameter of the suction pipe is
smaller than that of the pump:
c) The strainer and suction pipe are
partially obstructed:
REMEDIES
a) Dismantle the pump and clean it.
b) Clean all the pipes.
c) Check the tightness of the whole pipe, up to the pump, and make it tight.
d) Fill the pump to re-prime. Check that the foot valve is tight.
e) Loss of head on suction or suction height too great (check the NPSH of the pump
installed).
f) Interchange two phase wires on the motor terminal block or circuit-breaker to reverse
the direction of rotation.
g) Check the voltage on the terminals of the motor and the cross-sections of the
conductors.
h) Immerse the strainer (mini 20 cm). Ballast the flexible pipe if necessary.
a) Check the nuts of the stud bolts and tighten them fully.
b) Dismantle the pump and clean it.
c) Check that the pump turns freely without abnormal sticking.
d) Check the connections to the pump.
a) Check the voltage on the terminals of the motor; it should be within ± 10 % of the
rated voltage.
b) Dismantle the pump and clean it.
c) The motor is designed to operate at an ambient temperature of not more than +40°C.
a) Check the electrical power.
b) Clean the pump.
c) Let motor cool down.
a) Dismantle the pump and correct the problem.
b) Replace it.
c) Fill the pump and bleed until there are no more air bubbles.
d) Interchange two phase wires on the motor terminal block or on the circuit-breaker to
reverse the direction of rotation.
e) Replace them.
a) Check the current with an ammeter, or set to the current rating marked on the motor
data plate.
b) Check that the conductor cross-sections of the power cable are adequate.
c) Check it and, if necessary, replace the power cable.
d) Replace it.
e) Replace it.
a) Reread the installation conditions and recommendations in this data sheet.
b) The suction pipe must have the same diameter as the pump suction port.
c) Remove and clean.
ENGLISH
