Instruction Handbook KL
Chapter 8
BA KL V11 en
10/2014
page 8-2
Type of Fault
Possible Cause
Remedy
Pump does not suck
Incorrect direction of rotation.
Correct direction of rotation,
observe direction arrow.
Suction pipe blocked.
Clean suction pipe.
Valves not open completely.
Open valve completely.
Dry running
stator possible damaged.
Replace stator,
check dry-run protection for correct
connection.
Excessive pump noise
Joints are worn
Replace joints.
Joints worn, gear unit
damaged due to overloading or
alternating load.
Replace damaged parts, check
project planning of plant, monitor pressure;
reduce excessive
pressure.
Avoid high alternating loads.
Cavitation
speed too high or suction pipe
too narrow or blocked.
Check engineering data,
if necessary, select lower speed,
increase pipe cross-section.
Drive train deflected too widely
Use wide-angle drive shaft or set up drive
machine of pump in alignment.
Leak in mechanical seal
(GRD)
Seal rings worn.
Replace mechanical seal.
Excessive pressure in suction
housing.
Reduce pressure.
Spring action from medium.
(Medium settles into the spring
of the seal) This prevents the
adjustment of the seal rings.
Clean seal regularly.
Mount another mechanical seal .
Medium collects on the seal
rings.
Quench of face seal
(LWD) leaks on the
atmosphere side
Shaft sealing ring of mechanical
seal worn.
Replace shaft sealing ring and shaft holder of
seal.
Quench of face seal /
mechanical seal leaks on
product side
Cavitation
Inspect suction housing to verify
whether the pressure is too low in comparison
with the vapour pressure of the medium
Monitor the valves during pump operation to
verify that valves are completely open.
Pipe overgrown, clean pipe
8.2
Electrical Faults
Faults in the electrical drive system of the pumps or pump unit may have many different causes
(mains connection, dimensioning of the drive unit, motor protection, etc.).
Remove faults in connection with the electrical drive system by following the instructions contained
in the attached manufacturer’s operating and maintenance manual.
