User Manual

26 3296 M Group 6/05
Table 6
Troubleshooting Pump
PROBLEM /
MALFUNCTION PROBABLE CAUSE REMEDY
Motor requires
excessive power
Head lower than rating. Pumps too much
liquid
Install throttle valve.
Liquid heavier than expected. Check specific gravity and viscosity.
Head higher than rating, capacity at
rating
Check impeller diameter.
Rotating parts binding or severly worn
Check internal wearing parts for proper
clearances.
Condition
monitoring device
shuts down pump
Damaged sleeve & thrust bearings Replace as required.
Plugged recirculation circuit
Disassemble and remove blockage. Determine and
correct cause of blockage.
Recirculation liquid vaporization
Check actual liquid temperature versus design
temperature. Check actual NPSH available versus
design. Check minimum flow requirement for pump
size. Check recirculation circuit and flush screen for
blockage. Correct all as necessary.
Damaged containment shell Replace as required.
Magnets decoupled
Check temperature and viscosity of pumpage. Check
magnets with breakaway torque test.
Pump run dry
Check control device for proper operation. Check
suction line for blockage. Reprime pump.
Excessive motor power
System head lower than rating. Pumps too much liquid.
Check rotating parts for binding and wear. Liquid
heavier than expected.