Peripheral Pump Troubleshooting Guide

No Liquid Delivery

Motor Not Operational

Check Motor windings, phases and replace if required

Misalignment

Check coupling alignment, rubber condition and if coupling has become   disengaged.

Solids within pump

Check suction strainer, and pump internals for signs of solids

Bearing Seizure

Replace bearings

Inlet / Discharge valve closed

Open all valves

Lack of liquid

Check liquid level in tank

Direction of rotation

Check direction of operation

Strainer blocked

Backwash filter, or remove, clean and refit

Manometric Head too high

Check pump design against system design pressure

NPSH

Check NPSHR meets NPSHA

Vapor lock

Ensure pump is not drawing excess air, or small amounts of fluid are   not gassing within pump.

Excessive Power Consumption

Particles in discharge

Disconnect discharge, flush and refit

Collapsed Hose

Ensure rigid hoses are fitted

Pressure, viscosity, or fluid temperature outside design criteria

Check pump design against fluid characteristics and system   requirements

Particles within casing seizing impeller

Fit suction strainer. Remove all particles. Check impeller edge is straight   and vanes are not bent

Misalignment

Check coupling alignment, rubber condition and if coupling has become   disengaged.

Parts Worn

Replace parts worn such as bearings, mechanical seals, shaft.

End of Service life or adverse pumping conditions

Check installation and maintenance history of pump

Leakage from Pump

Seals not installed correctly

Refit / replace seals

Dry running

Replace seals. Correct system to prevent dry running

O Rings damaged

Check for particles, or seals trapped / twisted in casing

Worn Shaft

Shaft is now undersized due to wear. Replace shaft and seal

Excess System Pressure

System pressure is causing seals to leak. Check for blockages

O Ring Failure

Check o ring for signs of damage

Fasteners lose

Check torque of bolts

Thermal Expansion

Product could expand if heated within pump from recirculating fluid. Ensure   system is designed to prevent this.

Excessive static pressure

Check system and pump design pressures

Seal Faces Damaged

Check for particles and replace / clean filter. If frequent look to   replace seal with harder material, or magnetic drive pump.

Reduced Flow / Pressure Output

Incorrect Speed

Check VFD Settings

Motor Faulty

Check windings, and phases

Discharge Pipe Blocked

Clear blockage, flush and refit

Strainer blocked

Clean filter, backwash and refit

Inlet pipe dia

Increase inlet pipe diameter, or shorten if length is long

Foreign object in suction line

Check strainer. Flush inlet pipework

End of service life

Replace pump

Excessive Noise

Particles within Pump

Clear pump, strainer and check vanes for damage

Parts worn

Check for signs of wear

Motor Speed

Check Speed. Also check bearings and ensure electrical engineer checks motor. Check for air ingress in suction tank.