In fairness to all, we don't discuss pricing on the Wall. Thanks for your cooperation.
Venting risers after the supply valve?
I have a question regarding venting of my one-pipe steam system. I intend to vent my mains, and max venting would require 4 Gorton #2’s on one end and 3 on another. However, some of the risers are of considerable length from the mains and two even rival the short main in terms of volume (3ft^3+) and are 2-4 times the volume of the other risers. Having looked up some information from previous Wall posts and armed with Dan’s recommendation for venting oversized radiators, I thought it worth to ask if anyone has ever used the tappings on the radiators closest to the supply valve to aggressively vent the risers, as opposed to venting them before the valve, and a normal (say, Hoffman #6) vent in the typical far position to heat more slowly from that point. I figure this way I will have a better chance of balancing the system without all the hassle of tapping the risers.
The system is of modest size (267ft^2 EDR, radiators only, and 64 MBH), but has clearly been tinkered with (some of the radiators do not appear to be original). I have not performed a manual j for the house yet—I’m just getting my feet wet in that regard—to see if the system is sized properly. If my calculations are correct, the boiler (WM SGO-3) seems to be 34% oversized (358 ft^2 steam/86 MBH), but does provide DHW.
As a note, I still have the old asbestos on the piping (none on the near boiler) and plan to have it removed this summer and reinsulate. There appears to be a ¾” tapping at the end of the short main, but I can’t seem to locate one on the other main (I am hoping for a pleasant surprise when the asbestos is gone). So, in short, I won’t be experimenting with the vents until the fall, most likely. I was also wondering if anyone has had luck with balancing a system with the Macon or Danfoss TRV’s—seems like overkill for the $ but I figured I’d ask, especially if it could prevent buying additional vents for the radiators.