KSB CTN - 8 Trouble-Shooting

8 Trouble-shooting
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CTN / CTN-H
8 Trouble-shooting
WARNING
Improper work to remedy faults
Risk of injury!
▷ For any work performed to remedy faults, observe the relevant information
given in this instruction manual and/or in the product literature provided by the
accessories manufacturer.
If problems occur that are not described in the following table, consultation with the
KSB customer service is required.
A Pump delivers insufficient flow rate
B Motor is overloaded
C Excessive discharge pressure
D Increased bearing temperature
E Leakage at the pump
F Vibrations during pump operation
G Impermissible temperature increase in the pump
Table30: Trouble-shooting
A B C D E F G Possible cause Remedy
24)
✘ - - - - - - Pump delivers against an excessively high
pressure.
Re-adjust to duty point.
Check system for impurities.
Fit a larger impeller.
25)
Increase the speed (turbine, I.C. engine).
✘ - - - - ✘ ✘ Pump or piping are not completely vented or
primed.
Vent and/or prime.
✘ - - - - - - Supply line or impeller clogged Remove deposits in the pump and/or piping.
✘ - - - - - - Formation of air pockets in the piping Alter piping layout.
Fit vent valve.
✘ - - - - ✘ ✘ Suction lift is too high/NPSH
available
(positive
suction head) is too low.
Check/alter fluid level.
Install pump at a lower level.
Fully open the shut-off element in the
suction line.
Change suction line, if the friction losses in
the suction line are too high.
Check any strainers installed/suction opening.
Observe permissible speed of pressure fall.
✘ - - - - - - Wrong direction of rotation Interchange two of the phases of the power
cable.
✘ - - - - - - Speed is too low.
- Operation with frequency inverter
- Operation without frequency inverter
- Increase voltage/frequency at the frequency
inverter in the permissible range.
- Check voltage.
✘ - - - - ✘ - Impeller Replace worn components by new ones.
- ✘ - - - ✘ - Pump back pressure is lower than specified in
the purchase order.
Re-adjust to duty point.
In the case of persistent overloading, turn
down impeller.
25)
- ✘ - - - - - Density or viscosity of fluid handled higher
than stated in purchase order
Contact KSB.
- ✘ - - - - - Gland follower over-tightened or cocked Adjust.
- ✘ ✘ - - - - Speed is too high. Reduce speed.
25)26)
24) Pump pressure must be released before attempting to remedy faults on parts which are subjected to pressure.
25) Contact KSB.
26) The fault can be remedied by changing the impeller diameter