8
15
1530
series
group
1
trouble checK list
Refer to the following diagnostic section if
hydraulic problems are encountered in the
pump operation.
PROBLEM:
Not enough liquid, or no liquid
delivered.
CHECK:
Suction pipe and /or pump
casing not filled with liquid.
Speed too low.
(Result, reduced TDH).
Suction lift too high or insufficient
NPSHA. (Cavitation).
Impeller or suction pipe plugged
with solids.
Wrong rotation.
(Result, reduced TDH).
Air pockets in suction line or air
leaking in through packing
box area.
Suction strainer plugged, if used
in suction line.
PROBLEM:
Not enough pressure.
CHECK:
Speed too low.
Air or gases in the liquid.
Check impeller diameter.
Mechanical defects (impeller
clearance too great; impeller
damaged).
Wrong rotation.
Pressure gauge in a poor location.
PROBLEM:
Pump runs but intermittently
pumps liquid.
CHECK:
Suction line leaks.
Stuffing box leakage of air.
Air pocket in suction line.
Insufficient NPSH.
Air or gases in liquid.
PROBLEM:
Pump takes to much power.
CHECK:
Speed too high.
Head lower than rating; pump-
ing beyond design point.
Liquid heavier than specified;
check viscosity and specific
gravity.
Mechanical defects (Bent shaft,
rotating element binds, packing
too tight, misalignment).
