Xylem LOWARA e-MPA Manual De Instalación, Funcionamento Y Mantenimiento página 25

The pump is
overloaded
because 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.
7.7 The electric pump starts, but the
system's residual current device
(RCD) is activated
Cause Remedy
There is an ground Check the insulation of
(earth) leakage. the electrical system
components.
7.8 The pump runs but delivers too
little or no liquid
Cause
There is air inside
the pump or the
piping.
The pump is not
correctly primed.
The throttling on
the delivery side is
too extensive.
Valves are locked
in closed or
partially closed
position.
The pump is
clogged.
The piping is
clogged.
The rotation
direction of the
impeller is wrong
(three-phase
version)
The suction lift is
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.
Remedy
Bleed the air.
Stop the pump and
repeat the prime
procedure.
If the problem
continues:

Check that the
mechanical seal
is not leaking.

Check the
suction pipe for
perfect tightness.

Replace any
valves that are
leaking.
Open the valve.
Disassemble and clean
the valves.
Contact the local sales
and service
representative.
Check and clean the
pipes.
Change the position of
two of the phases on
the terminal board of
the motor or in the
electric control panel.
Check the operating
too high or the flow
resistance in the
suction pipes is too
great.
7.9 The electric pump stops, and then
rotates in the wrong direction
Cause
There is a leakage in one
or both of the following
components:

The suction pipe.

The foot valve or the
check valve.
There is air in the suction
pipe.
7.10 The pump starts up too
frequently
Cause
There is a leakage in one
or both of the following
components:

The suction pipe.

The foot valve or
the check valve.
There is a ruptured
membrane or no air pre-
charge in the pressure
tank.
7.11 The pump vibrates and
generates too much noise
Cause Remedy
Pump Reduce the required flow rate by
cavitation partially closing the on-off valve
downstream from the pump. If the
problem persists check the
operating conditions of the pump
(for example height difference,
flow resistance, liquid
temperature).
The motor Contact the local sales and
bearings service representative.
are worn.
There are Contact the local sales and
foreign service representative.
objects
inside the
pump
Impeller Contact the local sales and
rubs on the service representative.
wear ring
Coupling Check the coupling alignment.
misaligned
Flexible Check and replace the relevant
elements parts if there is any sign of wear.
of the
coupling
worn
For any other situation, refer to the local sales
and Service representative.
en - Original instructions
conditions of the pump.
If necessary, do the
following:

Decrease the
suction lift.

Increase the
diameter of the
suction pipe.
Remedy
Repair or
replace the
faulty
component.
Bleed the air.
Remedy
Repair or replace
the faulty
component.
See the relevant
instructions in the
pressure tank
manual.
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