Side Channel Pump Troubleshooting Guide

Delivery Rate too Low

Back pressure too high

Check duty point against curve

Suction Head too high, or supply pressure too low

Check liquid level. Open all valves on discharge

Blocked Filter. NPSH incorrect

Clean filters, and check suction pipework

Suction of air through pump shaft seal and stage casing seals

Replace any worn seals, gaskets, and O rings. Check shaft diameter for wear

Incorrect Rotation

Check direction of rotation

Air ingress through housing or suction line

Replace housing seal, and check flange gasket sealing. Check suction tank for signs of vortexing.

Pump not Priming

Suction of air through pump shaft seal and stage casing seals

Replace any worn seals, gaskets, and o rings. Check shaft diameter for   wear

Air ingress through housing or suction line

Replace housing seal, and check flange gasket sealing

Priming requirements too high

Check liquid level, and depth of suction pipe

Incorrect Rotation

Check direction of rotation

Pump not filled with fluid

Fill pump with fluid

Suction or discharge valve closed

Open all valves

Pipe connections not made correctly

Check all pipe connections

Electrical Connections

Check motor, absorbed power, winding resistance, phases

NPSH requirements not met

Check NPSH in line with pump curve

Screw Plugs in place

Remove screw plugs

Pump Leaking

Housing Screw Joints leaking

Check torque of housing screw joints and ensure match figures in manual

Misalignment

Check alignment and connections are stress free

Worn Seals

Replace Seals

Temperature Increase in Pump

Pump or Pipe not filled completely

Bleed pump and fill pump, suction and supply lines

Suction Head too high, or supply pressure too low

Check liquid level. Open all valves on discharge

Pump Dry running

Clean filters, and any dirt traps on suction side

Pump Noisy or Erratic

Priming requirements excessive, pump cavitating

Check liquid level, depth of suction pipe. Open all valves

Pump operating below minimum safe continuous flow

Clean all filters and suction pipe. Increase tank level. Check pump Impeller   and seals for wear.

Pump cavitating

Check supply pressure, and temperature of liquid

Excessive torque through magnetic coupling causing disconnection from   drive

Check pump for blockage. Check internal sleeve bearings, all operating   conditions and density of pumped liquid

Misalignment

Check pump setup. Check Coupling for wear and check alignment

Particles within pump

Check filter size and system operation

Motor operating on 2 phases

Check all electrical connections

Antifriction bearing worn

Check when NPSHR meets NPSHA pump operates smoothly

Motor protection switch tripped

Solids in Pump

Check pump, filters. Dismantle and clean pump

Discharge Valve Closed

Open Valve

NPSH

Ensure NPSHA meets NPSHR

Power consumption too high

Check motor protection switch and all electrical connections

Internal Friction

Pump blocked by particles. Shaft bearing worn, motor bearing worn,   stuffing box bolted too tight. Check viscosity of fluid.

No Fluid Delivery but Motor Operational

Excessive torque through magnetic coupling causing disconnection from drive

Check pump for blockage. Check internal sleeve bearings, all operating   conditions and density of pumped liquid