Install Instructions

7034000N Copyright © Liberty Pumps, Inc. 2022 All rights reserved. 11 | EN
Pump runs or hums, but
does not pump.
Discharge line blocked or restricted.
Check discharge line for foreign material, including ice if
discharge line passes through or into cold areas.
Check valve is stuck closed or installed backward.
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 head is beyond pump's capability.
Route piping to a lower level. If not possible, a larger
pump may be required. Consult Liberty Pumps.
Obstructed impeller or volute. Remove obstruction.
Pump is airlocked.
Turn pump off and let set for several minutes, then restart.
Add baffle to reduce trapped air bubbles.
Pump cycles too
frequently.
Improper float switch setting. Adjust float switch setting.
Check valve not installed, stuck open, or leaking.
Install check valve(s); remove check valve and examine
for freedom of operation and proper installation.
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.
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.
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 does not deliver
proper capacity.
Discharge valve(s) partially closed or clogged.
Check the discharge line for foreign material, including
ice if the discharge line passes through or into cold areas.
Check valve partially clogged.
Raise liquid level up and down to clear; remove check
valve to remove obstruction.
Incorrect motor rotation.
1-phase: contact factory.
3-phase: Correct 3-phase pump rotation direction. Refer
to section
3-Phase Pump Rotation Verification.
Total head is beyond pump's capability.
Route discharge piping to a lower level. If not possible, a
larger pump may be required. Consult Liberty Pumps.
Low liquid level. Check liquid level.
Obstruction in pump or piping. Remove obstruction.
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: contact factory.
3-phase: Correct 3-phase pump rotation direction. Refer
to section
3-Phase Pump Rotation Verification.
Foreign objects in the impeller cavity. Clean the impeller cavity.
Broken impeller.
Consult Liberty Pumps for information regarding impeller
replacement.
Table 2. Troubleshooting Matrix (continued)
Problem Possible Cause Corrective Action