vent question

jimmythegreek

Im wondering if its possible to vent a radiatior with a main vent at the top of the riser.  I have a large steam system (400k btu) with about 40 rads.  I'm in the process of using this site to help heat and balance out the system.  I have 2 specific risers that get no heat to the top floor (4th floor from boiler) and can get a little steam out of the lower floors by removing the radiator vents.  Im thinking of removing the floor valve for radiatior on both these risers on the top floor and using a tee instead with a main vent upright with a bushing and the other side of tee straight to the radiator.  I realize i wont be able to shut off radiator but i dont need to, ill take all the heat I can get there.  Am i dreaming or has this been done b4. the pipes to these risers from the main are under the building with no access and impossible to get to without a ton of damage and work, i doubt they are insulated.  Im attempting to make a small hole in the brick foundation to install a fan to help heat the underside from the existing full height basement to help a little.  its an easy install and may help, no harm if it doesnt.  thnx

Jamie Hall

A main vent

at the top of a riser, installed as you suggest, certainly won't hurt a bit and can help a lot.  Size it as well as you can, treating the riser as part of the main volume to be vented.  However, if this is a one pipe system, you're still going to have to vent that radiator.