Squirting Air Vent Quandary

DRoth80

I have an air vent attached to a 64-inch cast iron recessed radiator that is perpetually leaking when my steam boiler fires up. New vent was professionally installed and still leaking. My plumber opened the supply valve and concluded that since there was no water, it must be corrosion that is clogging the radiator and is suggesting a replacement. My boiler is about twelve years old and not in the best health. When previous owner installed the boiler he kept the old piping to save money. Some pipes are visibly corroded on the outside and have cauterized, and the spigot has lots of visible corrosion. Air vents attached to the three other radiators on the first floor make gurgling sounds but no condensate. Is this a boiler problem, or a radiator problem, or an air vent problem? Help!

KC_Jones

Sounds like a system problem, could be too much pressure, bad piping, wet steam. I know one thing, replacing a radiator won't fix anything.

What pressure is the boiler set for? Do all the radiators have pitch to the inlet valve? What is the meat boiler piping like? Pictures would help.

nicholas bonham-carter

Probably overpressure, under(main)venting, and dirty water are the cause of your problems.
Put a low (0-3 psi) pressure gauge on the pressuretrol pigtail, leaving the old gauge in place for code reasons, (even though it’s useless!) keep the pressure below 1.5 psi max.
Read up here on skimming to clean the boiler, and check your main vents. The new gauge will tell you if your main vents are up to snuff.—NBC