Air release ? in a converted gravity system

First off, forgive me if my terminology is off.

OK, I had an original "gravity" boiler system. The old expansion tank was way up in the attic. The tank/leftover pipes are higher than any radiator. I'm concerned about the air trapped in these pipes without a radiator to bleed. Do I simply insert an air release valve like the Taco slimeline hy-vent model below. Please see diagrams.

OLD SETUP

http://www.heatinghelp.com/pics/heating_p13_194x300.gif

NEW SETUP??

http://www.xjmllc.com/images/new.jpg

http://http://www.pexsupply.com/prod...305&brand=Taco

http://www.pexsupply.com/img/product...air%20vent.jpg

thanks!!

good question.. because you will never get the air out of the lines above the highest air vent in your system I am betting.

I'm now almost certain I need to connect the pipes (based on the first picture above) it's a supply and return piping through the tank.

Still, how do I remove this air in the pipes above the highest radiator (1 floor below)????

1) Just connect the pipes

2) Connect the pipes and add an air release in between them