Liberty Pumps 240 Serie Manual De Instalación página 4

Is my pump air-locked? What is an anti-airlock hole?
Air-lock is a term used to describe when air gets trapped in the volute/impeller area of a pump and cannot escape due to
the water column above the check valve on the discharge line. When the pit fills with water and the pump is called to
activate, the impeller spins in this pocket of air and cannot prime. "My pump runs, but does not pump anything" is the
symptom when this happens. An anti-airlock hole allows this trapped air to escape, allowing the pump to prime and start
pumping.
Liberty provides an integral anti-airlock hole in the volute housing of submersible pumps. Water spray from this hole is
normal while the pump is in operation. Bleeding off the air could take from several seconds to more than a minute once
the pump starts. To speed or assist with air bleed in the event of airlock, the addition of a 1/8" hole in the discharge pipe
is recommended. This hole should be no more than 1/8" diameter and drilled low on the pipe – just above the threaded
connection to the pump discharge. See Figure A above.
7. Connect additional pipe as necessary to direct the discharge to the desired location. Discharge should be kept as
short as possible with a minimum number of turns. Check all connections for security.
8. For added protection, consider the addition of a back-up pump such as Liberty's SJ10 SumpJet, as well as an
alarm such as Liberty's ALM-2 in applications where loss of pump function could result in property damage. If
an alarm is used, it must be connected to a separate electrical circuit.
Models 243, 233, and 453 come factory-equipped with
9.
a float switch mounted to the pump. This model has
two cords - one to the float switch and the other to the
pump motor. The switch cord has a series (piggyback)
plug enabling the pump (motor) cord to be plugged into
the back of it (see Fig. at right). The purpose of this
design is to allow temporary manual operation of the
pump if desired.
Figure A.
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Drill 1/8" anti-
airlock hole.
Water spray is
normal.
Fig. 1 Piggyback plug installation.
NORMAL
DON'T!
TEMPORARY
MANUAL
OPERATION
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