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Allow the pump to run for about 1-5 minutes. When
fi
ltration has ended,
the liquid “bubbling” noise should stop. The reservoir level will typically
drop during this bleeding process. Add more coolant and repeat as neces-
sary until the reservoir level stabilizes. (In the future, if you begin to hear
air bubbles rushing through the pump, it may indicate that more coolant
needs to be added.)
Filling & Maintenance
Pump Cavitation
The ERM-3K4U pumps can be sensitive to cavitation during the initial bleeding
process. If there is an air gap in the pump during power-up, the pump may not
be able to move it, resulting in an absence of coolant
fl
ow. The pumps need
to be “burped” to avoid this situation.
Reduce pump speed using the rear dial (but not low enough to stop the
pumps). While the pumps are running, gently tilt the ERM-3K4U unit in various
directions until coolant begins moving. This will be indicated by the pump’s
corresponding
fl
ow meter, located behind the reservoir. In some situations,
the ERM-3K4U unit may need to be completely inverted to properly burp the
pumps.
During regular operation, large air gaps should be restricted to the reservoir
and not cause cavitational issues.
