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3-1-618 Page 23
SECTION 3
TROUBLESHOOTING
PROBLEM
POSSIBLE
CAUSE SUGGESTED
ACTION
Pump Overloads Driver.
1.
Excessive pump speed
1.
Reduce pump speed and/or
and/or discharge pressure.
pressure.
2.
Blockage or closed
2.
Clean or open valve.
valve in discharge line.
3.
Improper bypass conditions.
3.
See recommended system
layout, and correct error.
Fluid Not Delivered.
1.
Pump not primed.
1.
Prime pump.
2.
Air or vapor pocket in
2.
Remove pocket from line.
suction
line.
3.
Clogged suction line.
3.
Clean out line.
4.
Suction and/or discharge
4.
Remove prop.
valves propped open.
Low Discharge Pressure.
1.
Worn or fluid cut valve
1.
Replace valve assembly.
assembly.
2.
Valve propped open.
2.
Remove prop.
3.
Pump cavitating.
3.
See Cavitation, Fluid Knock
or
Hammer
problem.
4.
Fluid leakage.
4.
Replace fluid end seals.
5.
Erroneous gauge reading.
5.
Recalibrate or replace
gauge(s).
Low Suction Pressure.
1.
Low head (NPSH).
1.
Raise fluid supply level.
Install
charging
pump.
2.
Insufficient charging pump
2.
Increase charging pump
capacity.
speed
or
size.
3.
Retarded fluid flow.
3.
Remove restrictions from
suction
line.
4.
Erroneous gauge reading.
4.
Recalibrate or replace
gauge(s).
Cavitation, Fluid Knock or Hammer.
1.
Improper suction system
1.
See recommended system
layout.
layout
in
manual.
2.
Low
suction
pressure.
2.
See Low Suction Pressure
problem.
3.
Suction stabilizer and
3.
Install suction stabilizer
pulsation dampener not used.
and pulsation dampener.
4.
Defective stabilizer or
4.
Repair and recharge or
dampener.
replace.