gushing water from radiator air vent: SOLVED

iddelz

i finally called my genius plumber / friend of my uncle's to try to solve the problem of water gushing out of the air vent of one of my rads. it got so bad, even after getting the system running at 0.5 to 1.5 psi, that in one day we soaked three bathroom towels sitting below the air vent. i think the problem is the subfloor piping to the radiator, which is screwy b/c we had a knucklehead plumber move rads during a renovation 2-yrs ago, and i know there's probably a lot of water sitting in it, not only b/c of the screwy piping but b/c it knocks at the start of the cycle. i'm ready to tear up part of my floor.

we go to ck the boiler and look at the near boiler piping and there's a hortizontal pipe to the header that's a little short but not worth getting into during heating season. i point out that the water level in the gauge is constantly below the recommended line on the boiler and ask him to show me how to clean the probe, thinking that's the problem. so he pulls off the jacket of the awf and ... no probe. knuckleheads. they put the probe elsewhere on the boiler and about 5" below the water line but the box at the water line so we'd never know. so he measures the height of the probe and it's below the the height of the close nipple of the hartford loop. that's the problem since it allows steam to push into the wet returns.

<a href="http://www.masterplumbers.com/plumbviews/2001/hartford.asp">[u][color=#810081]http://www.masterplumbers.com/plumbviews/2001/hartford.asp[/color][/u]</a>

since it would only take a little pressure to push water out of the screwy pipes under the subfloor that's why there was so much water on our floor. he does the completely counter-intuitive thing (to me at least) and ADDS water to the boiler. he tells me to keep it at the recommended line, above the close nipple, even if I have to do it manually. the whole time he's saying: "steam's great if it's engineered right but the problem with steam heat today is these knuckleheads [edited version] come in and pop in new boilers and never bother reading the manuals. the instructions are there for a reason." and now i have a dry radiator.

Steamhead

And when the weather turns warm

you can have it repiped, and everything will work as it should.