Troubleshooting - Lowara e-NSC Serie Manuel D'installation, D'utilisation Et D'entretien

6.3 Inspection checklist
Check the coupling
Check the mechanical seal
Checking the bearing seals
6.4 Disassemble and replace the pump parts
For more information about spare parts and assembly and disassem-
bly of the pump see Figure 1 ,
See the Repair and Assembly Instructions which are available for
download from our homepage.

7 Troubleshooting

7.1 Troubleshooting for users
The main switch is on, but the electric pump does not start.
Cause
The thermal protector incorpo-
rated in the pump (if any) has
tripped.
The protective device against
dry running has tripped.
The electric pump starts, but the thermal protection trips a varying time
after.
Cause
There are foreign objects (solids or
fibrous substances) inside the
pump which have jammed the im-
peller.
The pump is overloaded because
it is pumping liquid that is too
dense and viscous.
The pump runs but delivers too little or no liquid.
Cause Remedy
The pump is clogged. Contact the Sales and Service Department.
The troubleshooting instructions in the tables below are for installers
only.
7.2 The main switch is on, but the electric
pump does not start
Cause
There is no power supply.
The thermal protector incorpo-
rated in the pump (if any) has
tripped.
The thermal relay or motor
protector in the electric control
panel has tripped.
e-NSC Installation, Operation, and Maintenance Manual
Check the flexible elements of the
coupling. Replace the relevant
parts if there is any sign of wear
and check the alignment.
Check for leakage of the mechani-
cal seal. Replace the mechanical
seal if leakage is found.
Check correct seating of axial seal
rings mounted on the shaft. Only
gentle contact of the sealing lip
shall be established.
Figure 2 , Figure 3 , or Figure 4
Remedy
Wait until the pump has cooled
down. The thermal protector will au-
tomatically reset.
Check the liquid level in the tank, or
the mains pressure.
Remedy
Contact the Sales and Service
Department.
Check the actual power require-
ments based on the characteris-
tics of the pumped liquid and then
contact the Sales and Service
Department.
Remedy
• Restore the power supply.
• Make sure all electrical connec-
tions to the power supply are in-
tact.
Wait until the pump has cooled down.
The thermal protector will automati-
cally reset.
Reset the thermal protection.
Cause
The protective device against
dry running has tripped.
The fuses for the pump or
auxiliary circuits are blown.
7.3 The electric pump starts, but the thermal
protector trips or the fuses blow immediately
after
Cause
The power supply cable is
.
damaged.
The thermal protection or fuses
are not suited for the motor
current.
The electric motor is short cir-
cuit.
The motor overloads.
7.4 The electric pump starts, but the thermal
protector trips or the fuses blow a short time
after
Cause
The electrical panel is situated in an
excessively heated area or is ex-
posed to direct sunlight.
The power supply voltage is not
within the working limits of the mo-
tor.
A power phase is missing.
7.5 The electric pump starts, but the thermal
protector trips a varying time after
Cause
There are foreign objects (sol-
ids or fibrous substances) in-
side the pump which have jam-
med the impeller.
The pumps delivery rate is
higher than the limits specified
on the data plate.
The pump is overloaded be-
cause it is pumping liquid that
is too dense and viscous.
The motor bearings are worn.
7.6 The electric pump starts, but the system's
general protection is activated
Cause
A short circuit in the electrical system.
en - Translation of the original instructions
Remedy
Check the:
• liquid level in the tank, or the
mains pressure
• protective device and its con-
necting cables
Replace the fuses.
Remedy
Check the cable and replace as nec-
essary.
Check the components and replace
as necessary.
Check the components and replace
as necessary.
Check the operating conditions of the
pump and reset the protection.
Remedy
Protect the electrical panel from
heat source and direct sunlight.
Check the operating conditions
of the motor.
Check the
• power supply
• electrical connection
Remedy
Contact the local sales and service
representative.
Partially close the on-off valve down
stream until the delivery rate is equal
or less than the limits specified on
the data plate.
Check the actual power requirements
based on the characteristics of the
pumped liquid and replace the motor
accordingly.
Contact the local sales and service
representative.
Remedy
Check the electrical system.
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