Yet another main vent question

Larry Peck

My radiator vents hiss, which, at least in part, may be due to insufficient main venting. I would greatly appreciate if someone could advise me whether I have the right vents or not and what, if anything, should be done about their placement.

My home has two mains. The first is 3.0 inches in diameter and 61 feet long (not counting 18 feet after the main vent, which I assume does not matter). The vent for this main is a Gorton #1.

The second main is 2.5 inches in diameter and 55 feet long (not counting 13 feet after the main vent). The vent for this main also is a Gorton #1.

The main vents are 6 inches up on a nipple (one of which is from a 1/4 inch tap into the main). However, both are installed directly in the last elbow rather than 15 inches back as Dan's book recommends. Should the main vents be moved? Can I use a tee from which a riser has been removed to relocate a main vent? If so, what piping would be required to reduce from the 1 1/2 inch riser size to the appropriate vent size? Or, is it recommended that the piping be modified to accomodate new main vents?

I also suspect that there may be too much fire in the boiler. The boiler is an old Weil McLain and 7 of the originally 19 radiators have been disconnected. The nozzle size is 120 60. I fight with my oil company every year and it has been a battle just to get them to reduce the nozzle to this size. They just look at the size of the boiler and do not factor in the connected load. Do I need to know the total radiation load to know if this is the appropriate nozzle size?

Finally, I am looking for a good steam man in northern New Jersey to help with the above and some additional issues. Ken Secor's name has been favorably mentioned and I imagine that he is the person to contact. If he is too busy, could someone suggest anyone else?

Sorry for the long post and many thanks in advance to anyone who replies.

Larry