Best steam vents for one pipe radiators?

1890Exeter

Just bought a home this winter and now trying to balance my 12 radiators on 3 floors. Bought all new vents (about $8 each). All get rads get hot but the hottest ones air vents still whistle and release steam when they get hot. I thought the steam heat was supposed to cause the bell houseing to expand and push the pin into the air hole trapping the steam. Since they are new I don't think its because of corrosion build up.
I saw a three piece air vent for @ $115. Super expensive in my mind but I would bite the bullet if it was the only solution.
Is there a better product out there?
Any recommendations on books to get up to speed and a steam expert in the NH seacoast area would be much appreciated.

vaporvac

The Lost Art of Steam Heat found on this site....many hours of fascinating reading. You've got Stem is also good as a primer. What sort of venting do you have on your mains? They need to vent fast, while your rads vent slowly. Please post a pic of your boiler with it's piping and a representative rad. At what pressure is this running?

KC_Jones

First question, what pressure are you running at? What is teh pressuretrol set to? What is your main venting in the basement like? You need proper main venting before you can balance the radiators. What brand vents did you buy? There are several good brands on the market Gorton and Hoffman are a couple. At the price you mentioned I am guessing you got an imported brand perhaps USAV or maybe a Matco Norca. My experience with them is that they are garbage, but that might not be all your problem. As vaporvac suggested post some pics. And let us know some of the particulars of your system.

1890Exeter

Thanks. I will post pics this weekend