Fault tracing should be performed with the machine
in stand-by ensuring that the pumping unit cannot
re-start, even accidentally.
Always make sure that there is no-one near the
pump when it is started.
FAULT TRACING
Problems
Cause
Solution
The drive unit overheats
No pump-priming. The vacuometer
gives no values
No pump-priming even though the
vacuometer shows sufficient vacuum
Flow interruption after temporary stop
of the pump.
The pump has inadeguate capacity or
stops working
A) The fan belt has loosened or is
broken.
B) Motor suction filter is clogged
A) Defective tightness of the pump or
of the suction pipe.
B) The strainer is not completely
submerged.
C) The mechanical seal is broken
A) Clogged bottom strainer
B) The inner rubber coating of the pipe
has came off clogging it.
A) Water leakage in the suction pipe
because of defective retaining
quality
A) Insufficient engine speed
B) Clogged bottom strainer
C) Clogged pump casing
D) The inner rubber coating of the
suction pipe has come off
E) Impeller and wear plates are
wornout
A) Tension it or replace it
B) Clean it or replace it
C) For any cause other than A or B
read the manual "Care and
maintenance" of the engine
A) Check the pump tightness after
disconnecting the suction unit.
Connect the pump again and check
all connections and pipes. Replace
any faulty parts
B) Put the strainer deep down into the
water
C) Replace the mechanical seal
A) Take it up and clean
B) Replace it
A) Check the mechanical seal
B) Make sure that no liquid is coming
out of the suction valve
A ) Increase engine speed to reach the
correct range of revolutions
B) Clean the bottom strainer
C) Clean impeller and diffusers through
the cleaning door or dismantle the
pump casing
D) Replace suction pipe
E) Replace the parts
13
Use the following checklist as an aid to fault tracing.
It is assumed that the pump and installation have
been carried out as instructed.
Follow local safety regulations and observe
recommended safety precautions.
