Need help removing air from baseboard heat. HELP! !!!

[Will B.]

I am having a lot of noise coming from the expansion tank hanging in the ceiling of my basement and I can not get the air that is causing the noise out of the system. I have opened all the vents on each baseboard unit and get some air out every time the heat kicks on. Also if I open the pressure relief valve I get a large amount of air out before getting water or steam out. There is a small vent that is after the pump on the boiler that is also working.I get air out the vents even if the system isnt running. I'm afraid something is going to break or get damaged if I don't get this fixed.

So far I have drained the water out of the expansion tank (non bladder style) and I have also opened all the vents start the system and increase the pressure hoping to force the air out. Niether has worked and I am getting very frustrated with this. Pressure on tue system is at 13psi right now.

[HayZee518]

heater

your system is a closed loop hydrionic system, meaning all the headers and piping is filled with water and antifreeze. you said you drained the expansion tank, well there's supposed to be water in there. check the pressure valve on top of the tank. this could be your problem. the guts can be welded shut from rust.
normally the point the farthest out and up is where you bleed out air.