adding a steam main vent? should I?

Fred Harwood

A 30-foot main probably needs a large vent, which should help speed up steam arriving at the slow rads. Some more info might be helpful.
What vent is on the old main? Are the one-pipe mains conterflow or does the steam and condensate flow in the same direction to a main wet return?
What are the lengths of the two mains? Pipe sizes?

For example, if the mains are of similar length, they should use similar vents. Let us know more detail.

John Genereux

adding a steam main vent

I have a one pipe steam system in my house.
In the 50's an addition was added with another 30'
main line added to the original system. This new main feeds 4 radiators. These new radiators heat up much slower than the old ones. I am thinking I need to put a vent at the end of the new main but I am not sure. all the radiators in the house work and have new vents. If I do need a main vent how should i do it?

Thanks
John