new apartment -- steam riser air vent help

nybk222

I'm looking for some help regarding a steam riser and the proper way to vent it.

Background: I recently moved to top floor of a 7 story, ~70 unit apartment built in the late 50's. My unit has, what I believe are, four single-pipe in-wall fin tube radiators and a steam riser in the bathroom. The unit has no thermostat or control over the heat.

When I moved in, the riser had an air vent that was installed directly off of the pipe, wedged in a corner and completely painted over. When the building heat turned on a little over a month ago, the vent blew a hole through the paint and was releasing hot air and steam non-stop, and making a ton of noise. I was able to get my super to replace the air vent; the replacement unit had no manufacturer markings, but I think it was possibly an angled Maid-O-Mist with a #6 aperture. Unfortunately the replacement unit wasn't a major improvement over the previous vent, and while I was inspecting it, the body completely sheared off from the threading.

The issue: I was able to find and install an inexpensive Gorton #4 as pictured HERE. It does a significantly better job in terms of noise, although it hard to tell if it ever actually closes. While 90% of the time it appears to only release air, occasionally I'll see it spitting and dripping water from the vent hole. I suppose I should mention the riser itself has absolutely no trouble heating up.

• Is this a sign of a faulty vent, or is there something else to my situation?
  
• If I swap it out for something with a larger aperture like a Gorton D, would that make the problem worse in terms of leakage and noise?
  

This is just one of a few issues with the heating in my unit, but that's it for this topic. Thanks for reading!

nicholas bonham-carter

This seems like a sign of a faulty system. The vent of a properly functioning system should be silent, and close when steam arrives.
Get the super to log on here for some advice which will save his employers 30% in fuel cost, and make the tenants like you more comfortable!--NBC

Jamie Hall

What @nicholas bonham-carter said. What he's getting at is that the chances are, from you description, that the pressure is too high.

Kahooli

If you have lots of money to burn, put a 1-5psi steam gauge on it and see

JohnNY

@nybk222
It's a common thing to see in Brooklyn buildings. Over the years, Supers with just enough knowledge to make a mess of things have drilled and tapped risers to accommodate air vents that work well on radiators but don't do very much for a distribution riser. If the noise of the vent or its spitting water bothers you, take the vent out and put a ⅛" black or brass pipe plug in its place. If the riser needs to be vented, a proper tee fitting should be installed somewhere along the line, or fitted at the top at the last radiator connection, to accept a *main* type of air vent.
I consult on Brooklyn multi-family buildings all year long and the problems and failed attempts at solutions repeat themselves incessantly from address to address.

nybk222

Thanks for the responses everyone! I'm afraid any sort of comprehensive, actual building fix is probably not going to happen considering how long it took to get where I am now.

@JohnNY Can you recommend a main vent? From what I've seen, many of these appear to be larger than 1/8" NPT; would it work to step the size up using an adapter fitting?

JohnNY

nybk222 said:

@JohnNY Can you recommend a main vent? From what I've seen, many of these appear to be larger than 1/8" NPT; would it work to step the size up using an adapter fitting?

Once a nipple is screwed into a ⅛" hole, you're left with very little for the elimination of air. You would be far better served by using a drill and tap set to make the ⅛" hole larger to ⅜" (I'm assuming the pipe in question is 2" schedule 40 which has a wall thickness of 0.15") and install a Gorton #2 or similar vent with a ½" x ⅜" black steel or brass reducing fitting.