GE Profile PSCF3RGX Owner's Manual And Installation page 15

(on some models)
If no water is dispensed when the refrigerator is
first installed, there may be air in the water line
system. Press the dispenser arm for at least two
minutes to remove trapped air from the water line
and to fill the water system. To flush out impurities
in the water line, throw away the first six glassfuls
of water.
Never put fingers or any other objects
into the ice crusher discharge opening.
(on some models)