Liberty Pumps Pro370-Series - Manual (Page 8)

©Copyright 2012 Liberty Pumps Inc. All rights reserved 8
Risk of electric shock. Always disconnect the pump from the power source before handling or making
adjustments.
 NOTE: Liberty Pumps, Inc. assumes no responsibility for damage or injury due to disassembly in the field. Disassembly, other than at
Liberty Pumps or its authorized service centers, automatically voids warranty.
Problem Cause Correction
Pump will not run.
 Blown fuse or other interruption of
power; improper voltage.
 Check that the unit is securely plugged in.
Have an electrician check all wiring for proper
connections and adequate voltage and
capacity.
 Switch is unable to move to the
“turn on” position due to
interference with the side of basin
or other obstruction
 Position the pump or switch so that it has
adequate clearance for free operation.
 Insufficient liquid level.
 Make sure the liquid level is allowed to rise
enough to activate switch(s).
 Defective switch.  Remove and replace switch.
Pump will not turn
off.
 Switch(s) unable to move to the
“turn off” position due to
interference with the side of basin
or other obstacle.
 Position the pump or switch so that it has
adequate clearance for free operation.
 Defective switch.  Remove and replace switch.
Pump runs or hums,
but does not pump.
 Discharge is blocked or restricted.
 Check the discharge line for foreign material,
including ice if the discharge line passes
through or into cold areas.
 Check valve is stuck closed or
installed backwards.
 Remove check valve(s) and examine for
freedom of operation and proper installation.
 Gate or ball valve is closed.  Open gate or ball valve.
 Total lift is beyond pump's
capability.
 Try to route piping to a lower level. If not
possible, a larger pump may be required.
Consult the factory.
 Pump impeller is jammed or volute
casing is plugged.

 Remove the pump from the basin. Detach the
pump base and clean the area around the
impeller. Reassemble and reinstall.
Pump runs
periodically when
fixtures are not in
use.
 Check valve was not installed, is
stuck open or is leaking.
 Remove check valve(s) and examine for
freedom of operation and proper installation.
 Fixtures are leaking.  Repair fixtures as required to eliminate leakage.
Pump operates
noisily.
 Foreign objects in the impeller
cavity.

 Remove the pump from the basin. Detach the
pump base and clean the area around the
impeller. Reassemble and reinstall.
 Broken impeller.
 Consult the factory for information regarding
replacement of impeller.
 Worn bearings.
 Return pump to the factory or authorized repair
station for repair.
 Piping attachments to building are
too rigid.
 Replace a portion of the discharge line with
rubber hose or connector.
6. Maintenance and Troubleshooting