Troubleshooting
Model 3410 Installation, Operation, and Maintenance Manual
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Troubleshooting
Troubleshooting
Symptom
Cause
Remedy
The pump is not deliver-
ing liquid.
The pump is not primed.
Re-prime the pump and check that the pump and suction
line are full of liquid.
The pump has lost prime.
Check for leaks in the suction pipe joints and fittings.
Vent the casing to remove accumulated air. Check the
mechanical seal or packing.
The impeller is clogged.
Back-flush the pump in order to clean the impeller.
The impeller is loose on the shaft.
Check the key, locknut, and setscrews.
The shaft is rotating in the wrong direction. Change the rotation. The rotation must match the arrow
on the bearing housing or pump casing.
The shaft is not rotating at all.
Check the power, coupling, line shaft, and shaft keys.
The foot valve or suction pipe opening is
not submerged enough.
Consult an ITT representative for the proper submersion
depth. Use a baffle to eliminate vortices.
The suction lift is too high.
Check for obstructions at the inlet and make sure the
suction valves are open. Check for pipe friction losses.
Use a vacuum or compound gauge to check the NPSH
available.
The motor speed is too low.
Make sure that the motor wiring is correct and receives
full voltage or that the turbine receives full steam
pressure. The motor can have an open phase.
The system static head is too high.
Check with ITT to determine whether a larger impeller
can be used. If not, then cut pipe losses, increase the
speed, or both. Do not overload the driver.
The system head or discharge head is too
high.
Check for pipe friction losses and that the valves are
wide open. The condition can be corrected with larger
piping.