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Main Vent Identification?

Hey there, first I would like to thank everyone for the wealth of information here as I continue to learn about my 1-pipe steam system. After reading the wall I decided to look into my main venting. I have included some photos of my main vent and am hoping for some help in identification (sorry for the angle, it is wedged pretty far in a corner). Regardless, I am under the impression moving to something like a Gorton #2 would be beneficial. It would also give me the opportunity to pipe the vent a little more effectively if needed, since I would need to build an antler to fit it. I would appreciate any input. Thanks!


  • FredFred Posts: 7,814Member
    Wow, that vent is old. Does it still work? It most likely is too small to be effective. How long is your main and what diameter pipe? Do you only have one main? Depending on the length of your main, you may want to consider a Barnes and Jones Big Mouth vent. Twice the capacity of a Gorton #2, built from solid brass, and about the same price as a Gorton #2.
  • Jamie HallJamie Hall Posts: 10,279Member
    And do yourself - and the vent -- a favour when you put a new one on -- put it up on a short nipple, then 90 over and about a six inch nipple, and a 90 and up to the vent. It will be happier...

    On the choice of vent -- the Barnes and Jones is an excellent, high capacity vent -- but it doesn't close against water, so if that vent location is less than 28 inches times your cutout pressure in psi above the water line in your boiler, you should use the Gorton #2 instead.

    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England.

    Hoffman Equipped System (all original except boiler), Weil-Mclain 580, 2.75 gph Carlin, Vapourstat 0.5 -- 6.0 ounces per square inch
  • bmwdmb1bmwdmb1 Posts: 2Member
    Thank you for the suggestions. As far as I can tell the vent still “works”, though there are some issues with the system heating radiators on the 2nd floor.

    There is one long main (with the vent) and a much shorter one without an apparent vent. I can try to get measurements, though much of the piping is behind finished walls from the previous owner.

    I appreciate the note on the Barnes and jones though the potential to not close for water is slightly concerning as the vent is not located in an area where I could readily monitor things.

    Thanks again!
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