1900 Series Horizontal Splitcase Pumps
Instruction and Repair Manual
18
11/12/18
TROUBLE
PROBABLE CAUSE
REMEDY
3. Pump does not deliver rated
capacity.
a. Pump is not properly primed.
a. See 2a above.
b. Suction lift is too high.
b. See 1c above.
c. Excessive air in liquid.
c. See 1a above.
d. Air leakage through stuffing box.
d. See 1e above.
e. Driver is not operating at rated speed. e. See 2c above.
f. Impeller is clogged.
f. See 2d above.
g. Wearing rings are worn.
g. Replace wearing rings.
h. Impeller is damaged.
h. Replace impeller.
i. Pump is vapor bound.
i. See 2f above.
4. Insufficient pressure.
a. Excessive air in liquid.
a. See 3c above.
b. Driver is not operating at rated speed. b. See 2c above.
c. Wrong direction of rotation.
c. See 2e above.
d. Total head is too high.
d. See 2b above.
e. Wearing rings are worn.
e. See 3g above.
f. Impeller is damaged.
f. See 3h above.
g. Casing gasket defective allowing
internal leakage.
g. Replace casing gasket.
h. Liquid is vaporizing.
h. See 2f above.
5. Pump starts then stops pumping.
a. Air leaks in suction line.
a. See 1a above.
b. Air pockets in suction line.
b. Reprime the pump; eliminate air
pockets.
c. Water seal line is plugged.
c. Remove obstruction from water
line.
d. Excessive air in liquid.
d. See 1a above.
e. Suction lift too high.
e. See 1c above.
f. Defective packing or seal.
f. See 1e above.
g. Pump is vapor bound.
g. See 2f above.
6. Excessive power consumption.
a. Speed is too high.
a. Internal electric motor wiring is
incorrect; replace motor; refer
to applicable driver maintenance
manuals for possible troubles and
corrective action.
b. Wrong direction of rotation.
b. See 2e above.
c. Total head is too high.
c. See 2b above.
d. Total head is too low.
d. Re-evaluate head conditions;
correct as required. Consult
your local Fairbanks Nijhuis™
sales office.
e. Impeller is clogged.
e. See 2d above.
f. Impeller is binding.
f. Relieve strain on casing; adjust
impeller clearance.
g. Motor shaft is bent or worn.
g. Replace motor shaft.
h. Drive and pump are misaligned.
h. Realign driver with pump.
i. Power frame shaft is bent or worn.
i. Replace shaft.
j. Wearing rings are worn.
j. See 3g above.
k. Packing is incorrectly installed.
k. Install packing correctly.