Correct rotation
Reverse rotation
Disassemble and remove foreign matter
Pump clogged with foreign matter
Improve piping
Piping resonance
Open gate valve
Gate valve closed
Correct rotation
Reverse rotation
Check electrical connections
Electrical fault
Recalculate and adjust
Discharge head is high
Resize pipe
High frictional loss
Raise water level or lower pump
Air suction
Inspect and repair
Leaking from discharge pipe
Remove foreign matter
Clogging of discharge pipe
Remove foreign matter
Foreign matter in suction inlet
Remove foreign matter
Foreign matter clogging pump
Replace impeller
Worn out impeller
6
PROBLEM
POSSIBLE CAUSE
SOLUTION
Over current
Wait for supply to stabilise
Unbalanced current and voltage
Significant voltage drop
Inspect connections
Motor phase malfunction
Correct rotation
Reverse rotation
Replace pump with low head pump
Lower head. Excessive volume of water
Remove foreign matter
Foreign matter clogging pump
Replace bearing
Motor bearing worn or damaged
Correct rotation
Reverse rotation
Raise water level
Motor under protection from dry
running
Lower liquid temperature
Motor under protection from high
liquid temperature
Does not pump
adequate volume
Pu m p v i b r a t e s ,
causing excessive
operating noise
Pump running but
stops after a while
