Flexible Impeller Pump Troubleshooting Guide

Pump is not drawing in liquid (priming)

Suction pipework is not airtight

Remake any joints, ideally with sealant and not PTFE tape

Suction Line is blocked   or valve shut

Clear suction line and any valves

Impeller Damaged or   worn

Replace Impeller

Discharge Line blocked   or valve closed

Clean fittings and pipework on discharge line

Pump Pressure is Low

Impeller is worn or   wear plate damaged

Check impeller for   wear, cracks, tear, or chemical attack

Fluid Viscosity too   High

Check fluid viscosity in line with original specification

Pump Running Too Fast

Pump Speed May be too high for viscosity of Fluid

Pump Leaking

Mechanical Seal Defective, or O Ring worn

Check Mechanical   Seals and O Rings and Replace where needed

Pump is not  Operational

Impeller Stuck

Flush pump with   pumped medium to loosen impeller

Impeller Clogged or swollen

Remove any solids,   check impeller for chemical attack. Check impeller material against chemical to  ensure compatible. Check liquid Manufacturer has not changed the additives or   components of the fluid.

Dry Run Protection Activated

Reset. Check pump operating   conditions

Motor not Rotating

Have motor windings,   and resistance checked by qualified engineer.

Thermal Trip temperature is incorrect for pump location e.g. within warm engine room.

Repair/ Replace where required