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Subject to change without prior notice
INSTALLATION OPERATION AND MAINTENANCE INSTRUCTIONS
VERTICAL TURBINE PUMP - NVT SERIES
Ref. No. NVT-IOM/2020/V.01
Pum
p doesn’t start.
Pum
p runs w
itho
ut discharge.
Flo
w ra
te is insuff
icient.
Insuff
icient discharge pressure.
Pum
p ceases after running for a whil
e.
Pum
p requires ex
cessi
ve po
w
er
.
A
bn
ormal n
oise l
ev
el.
Ex
cessi
ve v
ibra
tions
Ex
cessi
ve l
eak a
t stuff
ing bo
x.
Stuff
ing bo
x is o
verhea
ting
Packing w
ears o
ut too fast.
Fault
Remedy
?
Electrical circuit open or not
completed.
Check circuit and correct
accordingly.
?
Low voltage supply to electric
driver.
Check whether driver wiring is
correct and receiving full voltage.
? ? ?
Speed is too low.
Check if driver is directly across the
line and receiving full voltage.
?
Defective motor.
Consult factory.
? ? ?
Wrong rotation.
Ensure that pump is rotating CCW
when viewed from above. Check
engagement of motor coupling.
?
Excessive horsepower
required.
Investigate and rectify the cause for
excessive horse power requirement.
?
Improper lateral adjustment.
Impeller binds against bowls.
Reset impeller adjustment.
? ?
Impellers adjusted too high.
Adjust impellers.
? ?
Closed discharge valve.
Fully open the discharge valve.
? ? ? ?
Obstruction in liquid passage.
Suction strainer clogged.
Pull pump, inspect suction strainer,
impeller and bowls.
? ? ?
Insufficient submergence of
pump bowls.
Lower pump if possible or adjust
water level in tank as necessary.
? ?
? ?
Cavitation.
Insufficient NPSH available.
Consider lowering the bowl
assembly by adding column.
10. FAULTS & REMEDIES
