7550000G
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13 | EN
Motor stops and then restarts
after short period but overload
heaters in starter do not trip.
Pump may be operating on a short cycle due to
basin being too small.
A larger basin may be required. Consult Liberty
Pumps.
Water returning to basin due to leaking check
valve.
Replace check valve.
Repeated tripping.
Circuit protection underrated.
Check rating and replace with proper size.
Current unbalance.
Check current draw.
Other appliance on same circuit.
Pump requires separate circuit.
Pump is connected to an extension cord or
wiring is inadequate or compromised.
Have an electrician check for proper wiring.
Improper voltage.
Have an electrician check all wiring for proper
connections and adequate voltage and capacity.
Obstruction in pump.
Remove obstruction.
Incorrect motor rotation.
1-phase: verify capacitor wiring, else consult
factory.
3-phase: correct pump rotation direction. Refer
to section
Foreign matter build-up.
Clean motor housing.
Rupture or failure of discharge
plumbing either inside or outside
of the basin.
Missing or faulty curb stop/swing check valve
allowing system pressure to feed back through
discharge piping.
Verify presence of a curb stop check valve or
replace curb stop/swing check valve assembly.
Pump runs periodically when
fixtures are not in use.
Check valve not installed, stuck open, or leaking.
Install check valve(s); remove check valve and
examine for freedom of operation and proper
installation.
Fixtures are leaking.
Repair fixtures as required to eliminate leakage.
Pump operates noisily.
Piping attachments to building are too rigid.
Replace a portion of the discharge line with
rubber hose or connector.
Incorrect motor rotation.
1-phase: verify capacitor wiring, else consult
factory.
3-phase: correct pump rotation direction. Refer
to section
Pump is being run below minimum head
requirement causing cavitation.
A different sized pump or impeller may be
required. Consult Liberty Pumps.
Foreign objects in the impeller cavity.
Clean the impeller cavity.
Broken impeller.
Consult Liberty Pumps for information
regarding impeller replacement.
Worn bearings.
Return pump to an authorized repair facility.
High level alarm triggering.
Missing or faulty curb stop/swing check valve
allowing system pressure to feed back through
discharge piping.
Verify presence of a curb stop check valve or
replace curb stop/swing check valve assembly.
Table 3. Troubleshooting Matrix (continued)
Problem
Possible Cause
Corrective Action
