Troubleshooting - Little Giant WRSC-6 Manual Del Propietário

Troubleshooting

Problem
Diaphragm switch.
Weak or hardened rubber dia-
phragm.
Plugged vent tube.
Dirt or sediment lodged
between retainer ring and rub-
ber diaphragm causing con-
tacts to remain closed.
Pump will not shut off
Pump is air locked.
Liquid inflow matches pump
capacity.
Defective switch.
Loose connection in level con-
trol wiring.
Check valve installed back-
wards.
Check valve stuck or plugged.
Lift too high for pump.
Pump runs but does
Inlet to impeller plugged.
not discharge liquid.
Pump is air locked.
Lift too high for pump.
Low voltage, speed too slow.
Pump does not deliver
rated capacity.
Impeller or discharge pipe is
clogged.
Impeller wear due to abrasives. Replace worn impeller.
Probable Causes Corrective Action
Replace switch.
Replace rubber diaphragm.
Clear vent tube of any obstructions.
Clean area around rubber diaphragm.
Shut power off for approximately 1 minute. Then restart. Repeat several
times to clear air from pump. If system includes a check valve, a 3/16" hole
should be drilled in discharge pipe approximately 2" above discharge con-
nections.
Larger pump required.
Disconnect switch. Check w/ohmmeter. Open-infinitive resistance, closed-
zero.
Check control wiring.
Check flow indicating arrow on check valve body to insure it is installed
properly.
Remove check valve and inspect for proper operation.
Check rating table
Pull pump and clean.
Shut power off for approximately 1 minute. Then restart. Repeat several
times to clear air from pump. If system includes a check valve, a 3/16" hole
should be drilled in discharge pipe approximately 2" above discharge con-
nections.
Check rated pump performance.
Check for proper supply voltage to make certain it corresponds to nameplate
voltage.
Pull pump and clean. Check pipe for scale or corrosion.
MAINTENANCE
Troubleshooting
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