4 Operation
Pay attention to possible faults.
Read the instructions carefully.
4.2
Trouble shooting
NOTE!
Read the maintenance instructions carefully before replacing worn parts.
Problem
Cause/result
Remedy
Motor overloaded
-
Pumping of viscous liquids
-
Larger motor or smaller impeller
-
Pumping of high density liquids
-
Low outlet pressure (counter pressure) -
Higher counter pressure (throttling)
-
Lamination of precipitates from the
liquid
-
Frequent cleaning
Cavitation:
-
Damage
-
Low inlet pressure
-
Increase the inlet pressure
-
Pressure reduction (sometimes to
zero)
-
High liquid temperature
-
Reduce the liquid temperature
-
Increase in the noise level
-
Reduce the pressure drop before the
pump
-
Reduce speed
Leaking shaft seal
-
Running dry
Replace:
All wearing parts
-
Incorrect rubber grade
If necessary:
-
Change rubber grade
-
Abrasive particles in the liquid
-
Select stationary and rotating seal ring
in silicon carbide/silicon carbide
-
Use of incorrect SiC/SiC single seal
-
Change to SiC/SiC seal marked “LKH
Prime”
Leaking O-ring seals
Incorrect rubber grade
Change rubber grade
No/little air release
-
Pump not properly primed
-
Ensure pump is primed
-
Pump speed too low
-
Increase pump speed during air
release
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