Main vents on cellar steam pipes

georgede54

My house is a rectangle set up so that there are four sets of radiators.

One set is two radiators in the back of the rectangle (one on each floor).

A second set is four in the front of the rectangle (two on each floor, separated by a wall).

A third set is four in the middle right side of a rectangle, (two on each floor, separated by a wall),

And the fourth set is four in the middle left of the rectangle, (two on each floor, separated by a wall).

I have located one vent located very close to the end of the pipes on the right middle side of the house.

Does anybody have any ideas on how I can tell whether this vent is working?

If it's not working, how might I fix it? Part of me would simply like to replace it, but the pipes are old and if I can't find something new that fits the old tapping (which I assume it has), I'd prefer to mess with the pipes as little as possible.

Also, assuming I could install new vents closer to end of the pipes that lead to the other sets of radiators (without causing these pipes to crumble), would I save a substantial amount of fuel by having 4 main vents in my basement as opposed to 1. Or would 1 main vent do the job essentially as well as 4?. What kind of savings might 4 main vents lead to?

I'm not saying the pipes are terrible. I don't know. But they are over 100 years old and seem to have a certain amount of surface rust on the portions where there is no insulation. So I assume the possibility that tampering with them could lead to greater problems than leaving them as is and making do with the one vent.

I've owned the house since 1996 and have only noticed that one main vent in the past two weeks, so it has been on its own for at least 23 years.

Thanks

Steamhead

Pictures?