
7327000G Copyright © Liberty Pumps, Inc. 2022
All rights reserved. 3 | EN
Do not run pump dry.
Do not block air vents.
Do not over-tighten prime plug (hand-tighten only).
Suction hose must not be longer than 15 ft.
Line could take up to 2 minutes to prime.
Do not submerge motor or allow motor to be exposed to
water.
Ambient temperature must not exceed 104°F (40°C).
Water temperature must not exceed 135°F (57°C).
Not for use with potable water or food products.
Pump retains water after use. In areas that are prone to
freezing temperatures, be sure to drain the pump before
storing it.
When used to transfer materials other than clear water (such
as glycol or vinegar), the pump must be flushed with water
and drained before storage to prevent potential pump
damage. Some chemicals used in hydronic systems can result
in corrosion of the aluminum pump housing.
Genera l Informa tion
This manual contains valuable information on the use of the
Liberty Pumps Model 331 Portable Transfer Pump. This
information is provided for safety and to prevent equipment
problems.
Before use, read the following instructions carefully. Each pump is
individually factory tested to ensure proper performance. Closely
following these instructions will eliminate potential operating
problems, providing years of trouble-free service.
This portable transfer pump is designed for such applications as
emptying water heaters, swimming pool covers, livestock tanks,
boats, etc. It can also be used for an intermittent pressure boost
for applications such as washing cars, cleaning driveways, etc.
When used for charging or servicing hydronic systems, the pump
must be flushed with clear water afterwards to prevent corrosion.
Periodically inspect the pump and system components, checking
for weak and/or worn hoses. Be sure all connections are secure.
Protect the electrical cord from sharp objects, hot surfaces, oil,
and chemicals. Avoid kinking the power cord.
Never remove the grounding blade from the power cord.
Cutting the power cord or plug will void the warranty and
make the pump inoperable.
Prepa ra tion
Adapters are furnished with the pump. The inlet and discharge are
threaded with ¾” NPT. Standard water pipe can be threaded
directly into the casting. If a garden or other hose is to be used,
the brass fittings must be installed. Use thread seal tape (4 wraps
max) or sealant on threaded fittings to ensure proper seal. Liberty
Pumps recommends that the swivel fitting be installed on the
front of the pump.
To reduce the possibility of hose collapse, use a high quality hose,
such as PEX or washing machine supply hose, on the suction line
(an ordinary garden hose may collapse under suction pressure
and should not be used).
A strainer is furnished and should be used if pumping from a
creek, pond, or source where foreign objects may be sucked into
the pump. The strainer helps prevent solids from entering the inlet
line.
The pump must be filled with water before operating. Do not run
pump dry. Running the pump dry will cause damage to the shaft
seal.
This unit is not waterproof or weatherproof and should not be
used in showers, saunas, or other potentially wet locations. The
motor is designed for use in a clean, dry location.
The pump draws fresh air in from the back and blows warm air out
the sides; do not block air vents. Ambient temperatures around
the motor should not exceed 104°F (40°C) in order to adequately
cool the motor. The motor is equipped with a thermal protector. If
the motor temperature rises, the unit will automatically turn off.
To reset the thermal switch, simply unplug the unit or turn the
power switch from on to off and allow the unit to cool. The switch
must be in the off position in order for it to cool down. The water
temperature should not exceed 135°F (57°C).
The Model 331 pump has been fitted with a 20 ft power cord. To
avoid the risk of electric shock, do not use an extension cord
unless absolutely necessary. Refer to Table 1 for proper wire
gauge for a 3-wire, grounding-type extension cord.
Grounding Blade
DO NOT REMOVE
Table 1. Extension Cord Length
Length Wire Size
25 ft 16 AWG
50 ft 16 AWG
100 ft 14 AWG