AC International 8200 Series Pump Operates For Short Time, Then Stops, Pump Takes Too Much Power

	TROUBLE SHOOTING (CONT.)
CAUSES		CURES
	Pump Operates For Short Time, Then Stops

30.Insufficient NPSHA.

31.System head too high.

32.Head lower than rating; thereby pumping too much liquid.

33.Cavitation

34.Mechanical defects.

35.Suction inlet not immersed.

36.Liquid heavier (in either viscosity or specific gravity) than allowed for.

37.Wrong direction of rotation.

38.Stuffing box glands too tight.

39.Casing distorted by excessive strains from suction or discharge piping.

40.Shaft bent due to damage

– through shipment, operation, or overhaul.

41.Mechanical failure of critical pump parts.

42.Misalignment.

43.Speed may be too high.

44.Electrical defects.

45.Mechanical defects in turbine, engine or other type of drive exclusive of motor.

See item 17.

See items 4 and 10.

Pump Takes Too Much Power

Machine impeller’s O.D. to size advised by factory or reduce speed.

See item 17.

See items 18, 19, 21, and 23.

See item 20.

Use larger driver. Consult factory for recommended size. Test liquid for viscosity and specific gravity.

See item 6.

Release gland pressure. Tighten reasonably. If sealing liquid does not flow while pump operates, replace packing.

Check alignment. Examine pump for rubbing between impeller and casing. Replace damaged parts. Repipe pump.

Check deflection of rotor by turning on bearing journals. Total indicator run-out should not exceed .002" on shaft and .004" on impeller wearing surface.

Check wear rings and impeller for damage. Any irregularity in these parts will cause a drag on shaft.

Realign pump and driver.

Check voltage on motor. Check speed versus pump nameplate rating.

The voltage and frequency of the electrical current may be lower than that for this motor was built, or there may be defects in motor. The motor may not be ventilated properly due to a poor location.

If trouble cannot be located, consult factory.

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