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Correct main vents for steam system

Steamhead Member Posts: 16,719
fron the beginning to the end of a single steam main? That's a lot of pipe. What diameter is it? Once you have this, the volume of air can be calculated, and the results tell you the main vent capacity needed.
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  • Steve Garson
    Steve Garson Member Posts: 191
    Correct main vents for steam system

    I just joined the facility committee of a neighborhood club heated with One-pipe steam. The building was built in 1918 and the are fresh air vents that have radiators, which I had only seen in Dan's book.

    The steam mains run around 150 feet, running in a "U-shape" around the perimeter of the building. I searched all over the basement and first floor for main vents and couldn't find a single one. The boiler is only four years old so I wonder if the installer removed them and never replaced them. Sounds crazy.

    Anyway, what size vents would I need to install at the end of the main run to effectively vent this system?
  • ed wallace
    ed wallace Member Posts: 1,613
    correct main vents

    would this be in the magus club in wellesley?

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  • Steve Garson
    Steve Garson Member Posts: 191

    It's the Windsor Club in Waban, Ed.

    The main starts off as what appears to be a 4-inch pipe and then gets smaller at the end. It's wrapped in asbestos, so I can't tell you what the smaller size is or when it changes down.

    After calculating the volume of air in the pipe run, what is the formula to determine the correct vent size? I never saw anything of the sort in Dan's books about steam.

  • Rodney Summers
    Rodney Summers Member Posts: 748
    Balancing steam systems using a venting capacity chart

    There is an e-booklet on sale here that explains how to empirically come up with the good venting scheme.

    Essentially you start by installing vents one by one. Each time you measure the time it takes your system to heat up at the radiators. When the addition of one more vent shows no decrease in heat up time, you know you've reached good venting.

    The booklet is by Gerry Gill and Steve Pajek.

    With steam heat, the Windsor Club must be a swanky place to be a member of. Good thing they've got you on the building committee.
  • Steve Garson
    Steve Garson Member Posts: 191

    Actually, the club isn't real swanky. All the neighbors back at the turn of the century took out a loan and built a club house and two tennis courts. Today, it's still for neighbors, but now has four courts, a pool, and three bowling lanes in the basement. I've got all summer to get the steam system working properly.
  • Rodney Summers
    Rodney Summers Member Posts: 748
    Have a wonderful summer

    Steam heat makes your club swanky for me...

This discussion has been closed.