Hi all, thanks for sharing your knowledge and advice here. It is greatly appreciated!
We have 1 pipe steam. Boiler replaced end of season 4 yrs ago. New one has mud valve but no skim port. We then did some renovations on the 3rd flr, leveling in new 3/4" subfloor w 3/4" hardwood over that. All radiators were replaced with properly sized newer units fitted to existing steam lines w factory nipples and new valves. Plumber used black dope and probably no wicking or teflon on the nipples where they met the old pipes. On initial fire up there was noise, lots, and leaking spitting vents on other floors too. That's when I got Dan's book and slowly got things sorted out. The following two seasons were warm and mostly quiet, but at the end of last season a small black drip mark appeared on the 2nd flr. riser. I figured a little excess dope on the connection above the ceiling had melted and worked its way down. But after a cold snap this Thanksgiving night (17 degrees) when no one was home this happened (see photos). Also drip marks on the other side of the riser wall below the 3rd flr radiator. Haven't been able to reproduce a leak at the 3rd flr nipple or valve but there's one photo shows what could be slight water staining on subfloor where the nipple enters. I should say that we did a setback on the thermostat this year of 4 degrees overnight. Towards the end of last season the vent on the radiator above that riser was buzzing a bit. (wet steam?) There's a lot of wood under that radiator and a beautiful 100+ yr old tin ceiling where the riser goes up on the 2nd flr. so I'm really hoping not to have to tear any of that out to deal with this. Would appreciate any advice you could share.
PS-The Co. that did the install now closed and unreachable.
Some relevant facts and photos below.
-3 story residential bldg.
- new boiler install never skimmed, wet returns not flushed either, lots of black water whenever I flush from mud valve
-Cut in looks to be between .75 & 1psi, Pressuretrol just below 10psi
-0-30psi gauge never moves off the 0 pin even when boiler is firing