[C320-list] Air in Water Heater?

[Timothy Osburn]

My water pump won't shut off after I close the taps.  I've checked all the
outlets in the head, cockpit shower and galley sink and as far as I can
tell, they are closed.  When I turn the water on in the galley sink, it
will sputter and then I get a steady flow of water (although it might
sputter again from time to time ) .  Looking at the ShurFlo documentation,
it sounds like there might be air in the water heater that is causing this
( it could also be a leak somewhere ).  Is there a way to vent air in the
heater?  Should I just try and continue to run water through the system
until the air in the water heater is displaced?  Any tips would be
appreciated.  Thanks.