Troubleshooting - Goulds Pumps 3996 Installation, Operation And Maintenance Instructions

TROUBLESHOOTING

TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Causes and Corrective Measures . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Problem
A. No liquid delivered, not enough liquid delivered, or not
enough pressure.
B. Pump works a while and then quits.
C. Pump takes too much power.
D. Pump is noisy or vibrates.
E. Pump leaks excessively at stuffing box
F. High bearing temperature
G. Stuffing box overheating
CAUSES AND CORRECTIVE MEASURES
1 Pump not primed or properly vented.
2 Speed too low.
3 System discharge head too high.
4 Suction lift too high.
5 Impeller or piping obstructed.
6 Wrong direction of rotation.
7 Air pocket or leak in suction line.
Stuffing box packing or seal worn allowing leakage of air
8
into pump casing.
9 Not enough suction head for hot or volatile liquids.
10 Foot valve too small.
11 Foot valve or suction pipe not immersed deep enough.
12 Entrained air or gases in liquid.
3996 IOM 9/2010
TROUBLESHOOTING
Cause
Possible Causes and Corrections
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 18, 19, 20.
4, 5, 7, 8, 9, 11, 12, 20.
6, 13, 14, 15, 16, 21, 22, 23, 24, 31.
15, 16, 17, 28, 31.
8, 24, 25, 26, 27.
15, 16, 17, 29, 30, 31.
8, 24, 25, 26, 27.
Remedy
Check that casing and suction pipe are completely filled
with liquid.
Check whether motor wiring is correct and receives full
voltage or turbine receives full steam pressure.
Check system head (particularly friction losses).
Check NPSH available (suction piping too narrow or long
may cause excessive friction losses). Check with vacuum
or compound gauge.
Check for obstructions.
Check rotation.
Check suction piping for air pockets and/or air leaks.
Check packing or seal and replace as required. Check for
proper lubrication.
Increase suction head, consult factory.
Install correct size foot valve.
Consult factory for proper depth. Use baffle to eliminate
vortices.
Consult factory.
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