Troubleshooting
Problem
Pump does not
turn on
Pump will not shut
off
Pump runs but
does not discharge
liquid
Pump does not
deliver rated
capacity
Pump cycles
continuously
Water sprays out
of a hole in the
discharge pipe
Probable Causes
Pump not plugged in
Circuit breaker off or fuse removed
Accumulation of trash on float
Float obstruction
Defective switch
Defective motor
Float or float rod obstruction
Pump is air locked
Liquid inflow matches pump capacity
Defective switch
Check valve installed backwards
Check valve stuck or plugged
Lift too high for pump
Inlet to impeller plugged
Pump is air locked
Lift too high for pump
Rotation incorrect (3-phase only)
Low voltage, speed too slow
Impeller or discharge pipe is clogged
Impeller wear due to abrasives
No check valve in long discharge pipe
allowing liquid to drain back into basin
Check valve leaking
Basin too small for inflow
There should be a bleed hole in the dis-
charge pipe that allows trapped air to
escape from the pump, preventing air
lock. Water spraying out of this hole is
completely normal
Corrective Action
Connect pump to a dedicated circuit
equipped with GFCI.
Turn on circuit breaker or replace fuse.
Clean float.
Check float path and provide clearance.
Replace switch.
Replace pump.
Check float and float rod path and pro-
vide clearance.
Remove pump and clean air bleed hole.
Larger pump required.
Replace switch.
Check flow-indicating arrow on check
valve body to ensure proper installa-
tion.
Remove check valve and inspect for
proper operation.
Check rated pump performance.
Pull pump and clean.
Remove pump and clean air bleed hole.
Check rated pump performance.
Switch any two of the line wires.
Check that supply voltage matches the
nameplate rating.
Pull pump and clean. Check pipe for
scale or corrosion.
Replace pump.
Install a check valve for correct opera-
tion.
Inspect check valve for correct opera-
tion.
Install larger basin.
No corrective action is required.
MAINTENANCE
Troubleshooting
7