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CONTENTSWhen Something Goes Wrong

Pump Won't Start ........................ ....................... ........ Page 2Pump Runs, But Does Not Produce EnoughFlow (GPM) ................................................................... Page 3Pump Runs, But Cycles Too Often .................... ..... Page 4Pump Runs, But Fuses Blow or Heaters Trip ....... Page 5Pump Runs, But Makes Noise .......................... ....... Page 6Pump Runs, But Leaks ............................................... Page 7

Measurement and TestingAmperage Check ...................... ....................... ............ Page 8Checking Current Imbalance (3-phase) ............... Page 8Capacitor Check ........................ ....................... ........... Page 9Supply Voltage Check ........................ ........................ Page 9Motor Winding Resistance (lead-to-lead) ......... Page 10Insulation Resistance (lead-to-ground) ............. Page 10

Engineering

Formulas ..................................................................... Page 11Metric Conversions ........................ ........................ .. Page 12Water Vapor Pressure and Specific Gravity ...... Page 13Water Properties at Different Altitudes ............ Page 14

CRTroubleshooting

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When Something Goes Wrong. . .

Pump Won't Start

Possible Cause Check This By. . . Correct This By. . .

No power at the motor Check for voltages at the motor'sterminal box. See page 9 for instructions.

If there is no voltage at the motor, checkthe feeder panel for tripped circuits andreset those circuits.

Turn off the power and remove the fuses.Check for continuity with an ohmmeter.

Replace the blown fuses or reset thecircuit breaker. If the new fuses blow orthe circuit breaker trips,the electricalinstallation, motor, and wires must bechecked for defects.

uses are blown or the circuit breakersave tripped

Check for voltage on the line and loadside of the starter. Check the amp drawand make sure the heater is sizedcorrectly.

Replace any burned heaters or reset.Inspect the starter for other damage. Ifthe heater trips again, check the supplyvoltage. Ensure that heaters are sizedcorrectly and the trip setting isappropriately adjusted.

Motor starter overloads are burned orave tripped

Energize the control circuit and check forvoltage at the holding coil.

If there is no voltage, check the controlcircuit fuses. If there is voltage, checkthe holding coil for weak connections.Ensure that the holding coil is designedto operate with the available controlvoltage. Replace the coil if defects arefound.

tarter does not energize

Check all safety and pressure switchesfor defects. Inspect the contacts in

control devices.

Replace worn or defective parts orcontrols.

Defective controls

Turn off the power and disconnect thewiring. Measure the lead-to-leadresistance with an ohmmeter (set toR x 1). Measure the lead-to ground valueswith an ohmmeter (set to R x 100K). Seepage 10 for instructions. Record thesemeasurements and compare them to therated values for your motor.

If an open or grounded winding is found,remove the motor and repair or replaceit.

Motor is defective

Turn off the power and discharge the

capacitor by shorting the leads together.Check it with an analog ohmmeter (setto R x 100K). See page 9 for instructions.

When the meter is connected to thecapacitor, the needle should jumptoward 0 (zero) ohms and slowly driftback to infinity ( ). Replace thecapacitor if it is defective.

Defective capacitor (on single phasemotors only)

8

Turn off the power and manually rotatethe pump shaft.

If the pump shaft doesn't rotate, removethe pump and examine it. If necessary,disassemble it and check the impellersand seal for possible obstruction.

The pump is stuck

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When Something Goes Wrong

Pump Runs, But Does Not Produce Enough Flow (GPM)

Possible Cause Check This By. . . Correct This By. . .

Shaft is turning in the wrongdirection

Check the rotation of the coupling ormotor fan. It should be rotatingcounterclockwise whenviewed from the top. Check

the wiring for proper connections.

Correct the wiring. For single pmotors, check the wiring diagram omotor. For three phase motors, siswitch any two power leads.

Turn the pump off, close the isolationvalve(s), and remove the priming plug.Check the level of the water within thepump.

Refill the pump, replace the priming and start the pump (any long suclines should first be filled with wbefore starting the pump).

Pump is not primed or is airbound

Remove and inspect the strainer, screen,or valves.

Clean and replace any defective straiscreens, or valves.

The strainers, check valves, or foot valvesare clogged

Check the piping for leaks with soapywater. Watch the shaft immediatelyafter the pump is turned off. If it runsbackward, there may be leaks.

The suction pipe, valves, and fittmust be made tight. Repair any and retighten all loose fittings.

There are leaks in the suction or dischargepiping

Install a pressure gauge near thedischarge port, start the pump, and

gradually close the discharge valve. Readthe pressure at shutoff. (Do not allowthe pump to operate for an extendedperiod at shutoff.)

Convert the PSI you read on the gauFeet of Head by:

Refer to the pump curve for the myou are working with to determinshutoff head you should expect formodel. If that head is close to the fi

you came up with (above), the pumprobably OK. If not, remove the pand inspect impellers, chambers, e

Parts or fittings in the pumpare worn

Install a pressure gauge near the

discharge port. Bleed off any pressure inthe tank or boiler. Start the pump andgradually close the discharge valve. Readthe pressure at shutoff. Open the valvevery slowly, noting the dischargepressure reading.

Impellers are clogged

TopView

Install a compound pressure gauge atthe suction side of the pump. Start thepump and compare the reading to thepublished performance and NPSH datafor that pump.

Reduce the suction lift required opump by lowering the pump, increathe suction line size, or removing friction loss devices on the suction

Not enough NPSH available

Check for voltages at the motor'sterminal box. See page 9 for instructions.

Incorrect Supply Voltage orMotor Wiring Combinations Do NotMatch Voltage Supply

If the wrong voltage is found, mcorrection. If the motor wicombination allows for multiple suvoltages, change wiring combinatimatch supplied voltage.