Submersible Motor Pumps
(150 mm and above)
9
11.2 Pump
Pump fails to deliver the water
Pump delivers insufficient flow of water
Pump does not develop required head / pressure
Pump has vibrations and noise
Possible causes
Remedies
•
Unavailability of power.
Check the line.
•
Defective motor winding, cable and starters.
Repair / replace the defective parts.
•
Coupling / motor shaft worn out.
Take out pump-set for repairing of the damaged
Motor runs while pump remains stationary.
parts.
•
Pump is silted up.
Clean the suction casing, Impeller, Stage casing
and non return valve - (1).
•
Pump set broken away from the riser pipe as a
Consult Installer.
result of corrosion.
•
•
Rotational speed is too low.
Check supply frequency and increase the voltage
up to tolerance limit as shown on name plate.
•
Pump delivers against an excessive discharge
Open discharge valve to attain desired flow.
pressure.
Reduce no. of bends, increase the pipe size.
•
The pump delivers higher flow of water against low Regulate discharge valve till the duty flow is
discharge pressure.
attained.
•
Leakage in pipes.
Change the pipe.
•
•
•
Excessive wear of pump internal.
Replace the worn-out components - (1).
•
•
•
Closed riser pipe.
Replace defective length of riser pipe with new
gasket.
•
Discharge pipe coated with depositions.
Clean the pipe and remove the deposition or
Replace the pipe.
•
Incorrect installation.
Consult Installer.
•
Loose assembled parts
Tighten the fasteners.
Ensure the operating parameters with respect to
•
Positive suction head is too low
specified duty parameters and the correctness of
submergence as specified.
(1) Consult KSB
