13 TROUBLESHOOTING
FAULT
CHECK (Possible cause)
REMEDY
1.
The motor does not start
and makes no noise.
A.
Make sure motor is live and check
that the mains voltage corresponds
to the one on the data plate.
B.
Check the protection fuses.
C.
The float switch prevents startup.
D.
The shaft is not turning.
A.
If they are burnt-out, change
them.
B.
Make sure float moves freely and
check its efficiency.
C.
Turn the shaft as indicated in the
Warnings chapter
(Paragraph
6.3. ).
2.
The pump does not
deliver.
A.
The suction filter or the pipes are
obstructed.
B.
The impellers are worn or blocked.
C.
The check valve, if installed on the
delivery pipe, is blocked in closed
position.
D.
The fluid level is too low. On starting,
the water level must be higher than
the filter level.
E.
The head required is higher than the
pump’s characteristics.
A.
Remove the obstructions, as
indicated in the Warnings chapter
(Paragraph 6.4).
B.
Change the impellers or remove
the obstruction.
C.
Check good operation of the
valve and replace it if necessary.
D.
Regulate the length of the float
switch cable (See chapter on
Warnings - Paragraph 9.2.).
3.
The pump does not stop.
A.
The float does not interrupt the
operating of the pump.
A.
Make sure float moves freely and
check its efficient.
4.
The
flow
rate
is
insufficient.
A.
Ensure that the suction filter is not
partly blocked.
B.
Ensure that the impellers or the
delivery pipe are not partly blocked
or fouled with scale.
C.
Ensure that the impellers are not
worn.
D.
Ensure that the check valve (if fitted)
is not partly clogged.
E.
Check the direction of rotation in
three-phase versions (See Chapter
on Electrical connection - Paragraph
8.4.).
A.
Remove any obstructions, as
indicated in the chapter on
Warnings (Paragraph 6.4.).
B.
Check good operation of the
valve and replace it if necessary.
C.
Change the impellers.
D.
Accurately clean the check valve.
E.
Invert two wires in the power
cable.
5.
The overload protection
device stops the pump.
A.
Ensure that the fluid to be pumped
is not too dense because it would
cause overheating of the motor.
B.
Ensure that water temperature is not
too high (see liquid temperature
range).
C.
The pump is partly blocked by
impurities.
D.
The pump is mechanically blocked.
A.
Reduce liquid temperature. Wait
until thermal protection switch
resets, about 20 mins.
B.
Accurately clean the pump.
C.
Check for the occurrence of
rubbing between moving and
fixed parts; check the state of
wear of the bearings (contact the
supplier).
8
