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Steam Pressure

I have ordered and read one of the books on this web site. I read that my old steam boiler should be putting out no more than 2 PSI through my one pipe steam system. My boiler is an old National built in the 40's. I just bought this old house (1891) and it is my first time dealing with steam heat. The people before me had the boiler serviced by Agway. Agway bypassed the pressuretrol (-maybe it didn't work) and my system has no pressure guage on it. How much pressure do you think is going through my pipes and how dangerous is it? Can I just tap a hole in one of my pipes and thread in a gauge? How can I adjust this pressure so I'm only putting out 2 PSI?

Help Please! Thanks,


  • Steamhead (in transit)
    Steamhead (in transit) Member Posts: 6,688
    First thing to do

    is get a REAL steam pro in there. NOT Agway- whichever of their techs bypassed the Pressuretrol and removed the gauge should be shot! You were very, very lucky nothing blew up or out.

    A new pressure control and gauge are needed. I'd spend the extra money and get a Vaporstat that cannot be set higher than a pound. Your house has probably had energy-saving upgrades since it was built, such as insulation, storm windows etc. The 2-pound specification would have applied to the house as first built, and even then was probably more than needed.

    When it comes time to replace that old National boiler, the Vaporstat can be used on the new one if it's in good shape and not too old.

    To locate a steam pro in your area, click on Resources above, then Find a Professional and follow the instructions.

    To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"
  • Big Ed_3
    Big Ed_3 Member Posts: 170

    Pressuretrol bypassed ? Shut it down and call in a pro .Do not run unit.What you have now is a bomb .
  • Dave_4
    Dave_4 Member Posts: 1,405
    Bomb indeed

    Bypassing your operational controls is like finding your car with sluggish acceleration and solving it by putting a cement block on the pedal and disconnecting the brakes.

    Anyone who bypasses an operational and/or safety control and leaves it like that should have their license (if they have one) revoked and possibly arrested, IMHO. They could also be liable for manslaughter charges if something went wrong.
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