Self Priming Pump Troubleshooting Guide

Pump not Priming

Casing is Empty or level of fluid is insufficient

Fill pump with Fluid

Liquid temperature in casing overheated

Add additional fluid, as liquid has recirculated within pump head for   too long

Air Ingress

Check all pump seals, shaft clearance, suction pipework for possible  air entry points

Pressurised Delivery Line

Ensure air can escape from delivery line

Low Speed

Ensure pump speed is correct and any inverter settings are correct.   Check data against performance curve

Impeller worn / broken

Check impeller condition

Volute worn

Check volute / casing for wear and that the leading edge (cutwater) is   intact. Volute/casing should be replaced with impeller to maintain efficiency

Strainer blocked

Check any suction strainers for blockage

Suction lift requirements Excessive

Check suction pipework friction losses and vertical lift

Suction / Discharge lines blocked

Clear all blockages, check all filters and valves

Zero fluid delivery

Pump not primed

See above section

Backpressure too high

Required pressure is beyond capability of pump. Evaluate system   specification & design against supplied pump.

Friction losses

Check friction losses of all components

Impeller Clogged

Clear impeller and clean

Suction / Discharge lines blocked

Clear all blockages, check all filters and valves

Flow Rate Insufficient

Air Ingress

Check all pump seals, shaft clearance, suction pipework for possible air entry points. Check inlet tank for vortex formations.

Impeller worn / broken

Check impeller condition or wear plate. Wear plate replacement may not lead to original pump performance being restored.

Select a design where changing the volute will lead to original performance being resored as in our XR Series

Suction Line Diameter

Suction line diameter too small, viscosity of fluid higher than   expected, level of fluid in inlet tank too low

Pump Pressure Insufficient

Liquid Viscosity

Liquid viscosity is higher than expected

High Absorbed Power

Rotational Speed

Check Rotation speed is in line with design, it could be too high

Cavitation

Head is too low, or delivery pressure requirements too high

Liquid Density

Liquid Density is higher than expected

Misalignment

Check alignment of pump, coupling and check coupling rubber

Internal Friction

Friction between the pump rotating and non-rotating parts

Particles within pump

Check fluid and pump for signs of particle ingress. Check inlet   filters are sized correctly

Vibration

Pump delivery too low

Check NPSHR is being met. Place pressure gauges on discharge and   compound gauges on suction

Pump or pipework not fixed

Check Pump is correctly fixed to baseplate, and pipework is not loose

Cavitation

Check NPSHR meets NPSHA

Particles within pump

Check fluid and pump for signs of particle ingress. Check inlet   filters are sized correctly

Pump Jams

Mechanical Breakdown

Check shaft, coupling, motor, pulleys belts and gearboxes for damage

Particles within pump

Check fluid and pump for signs of particle ingress. Check inlet filters are sized correctly

Short Bearing Life

Lubrication

Ensure bearings are lubricated in accordance with procedure

Cavitation

Check NPSHR meets NPSHA

Particles within bearings

Replace bearings

Bearings Rusty

Replace bearings

Mechanical Seal Leakage

Particles within pump

Check fluid and pump for signs of particle ingress. Check inlet filters are sized correctly.

Cavitation

Check NPSHR meets NPSHA

Seal overheats

Low Fluid level in pump. Check system and operating procedure. Fluid   is recirculating for too long