Pentair STA-RITE - Troubleshooting; Electrical; Mechanical; System

Troubleshooting 15
Cause Corrective Action
Electrical
A.Novoltageinpowersystem.
Check phase-to-phase on line side of starter contactor.
Check circuit breaker or fuses.
B.Novoltageononephase(ThreePhaseunits).
Check phase voltage on line side of starter contactor. Isolate open circuit (circuit breaker, fuse,
broken connections, etc.)
C.Lowvoltageatmotor.
Runningvoltageacrosseachlegofmotormustbe±10%ofnominalvoltageshownon
nameplate.
D.Motorleadsimproperlygroupedforvoltage. Refertoleadgroupingdiagramonmotornameplate.
E.Controlfailure. Checkcontroldevice,startercontactor,H-O-Aselectorswitch,etc.,formalfunction.
F.Thermaloverloadswitchopen Check phase-to-phase on line side of starter contactor.
G.Installationfailure. Check motor or windings to ground with megohmmeter.
H.Openwindings. Check leg-to-leg with ohmmeter.
I.Frequencyvariation. Checkfrequencyofpowersystem.Mustbelessthan5%variationfrommotornameplaterating.
Mechanical
A.Flowthroughpumpcompletelyorpartiallyobstructed. Locateandremoveobstruction.Refertorepairinstructionsfordisassembly.
B.Wrongdirectionofrotation.
Reverserotationofthreephasemotorbyinterchanginganytwoleads.Seemanufacturer’s
instructions for reversing single phase motor.
C. Pump lost prime. Reprime.Inspectsuctionsystemforairleaks.
D. Internal leakage. Checkimpellerforwearofcontrolledclearances(SeeRepairInstructions).
E.Looseparts Inspect.Repair.
F.Stuffingboxnotproperlyadjusted Adjust gland.
System
A. Pressure required by system at design flow rate exceeds
pressure rating of pump.
Compare pump pressure and flow rate against pump characteristic curve. Check for closed or
partially closed valve in discharge piping system.
Reducesystempressurerequirement.Increasepressurecapabilityofpump.
B.Obstructioninsuctionpiping Locateandremoveobstruction.
C. Pressure rating of pump exceeds pressure requirement
of system at design flow rate.
Compare pump pressure and flow rate against pump characteristic curve.
Inspect discharge piping system for breaks, leaks, open by-pass valves, etc. If necessary, reduce
flow rate by partially closing discharge valve.
Symptom
Probable Cause
Electrical Mechanical System
A B C D E F G H I A B C D E F A B C
Pump runs, but no water delivered X X X X
Notenoughwaterdelivered X X X X X X X X
Notenoughpressure X X X X X X X X
Excessivevibration X X X X X X
Abnormal noise X X X X X X X
Pump stops X X X X X X X X
Overheating X X X X X X X X X