Troubleshooting, Operation troubleshooting, Oubleshooting – Goulds Pumps 3171 - IOM User Manual
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Troubleshooting
Operation troubleshooting
Symptom
Cause
Remedy
The pump is not delivering
liquid.
The pump is not primed.
Make sure the pit is filled with liquid above the
casing. On dry pit units, the casing and suction
pipe must be completely filled.
The discharge head it too high.
Check the total head, particularly friction loss.
The motor speed is too low.
Check the motor speed.
The suction line is clogged.
Remove the obstructions.
The impeller, discharge pipe, or strainer is
clogged.
Remove obstructions or back-flush the pump.
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 suction lift is too high.
Shorten the suction pipe.
The amount of available NPSH is not sufficient. Check the amount of NPSH available and required
and adjust accordingly.
The pump is not producing
the rated flow or head.
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 discharge head is higher than expected.
Check the total head, particularly friction loss.
The impeller, discharge pipe, or strainer is
clogged.
Remove obstructions or back-flush the pump.
The motor speed is too low.
Check the motor speed.
The suction line is clogged.
Remove the obstructions.
The suction lift is too high.
Shorten the suction pipe.
The impeller is worn or broken.
Inspect and replace the impeller if necessary.
The suction line has air or vapor pockets.
Rearrange the piping in order to eliminate air
pockets.
The amount of available NPSH is not sufficient. Check the amount of NPSH available and required
and adjust accordingly.
The pump starts and then
stops pumping.
The pump is not primed.
Re-prime the pump and check that the pump and
suction line are full of liquid.
The float controls are not adjusted properly.
Check the float controls.
The strainer is clogged.
Check the sump for large items that the pump may
be picking up. Check if the bearings are running hot.
The suction line has air or vapor pockets.
Rearrange the piping in order to eliminate air
pockets.
The suction line has an air leak.
Repair the leak.
The bearings are running hot. The pump and driver are not aligned properly. Realign the pump and driver.
There is not sufficient lubrication.
Check the lubricant for suitability and level.
The lubrication was not cooled properly.
Check the cooling system.
Troubleshooting
48
Model 3171 Installation, Operation, and Maintenance Manual