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Pressuretol setting on new steam boiler

Mike K_9
Mike K_9 Member Posts: 2
I just had a new steam boiler installed. The pressuretol is set at 6-8 psi. I know that Dan recommends cranking it way down. I have a very large house; should that matter? Should I turn it down?


  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,576
    pressure adj

    we have 60 rads, 1,000,000 btu boiler.most of the time our system operates in the 2-6 oz. range.
    as i understand it, steam is less viscous, and moves more quickly through the pipes at these low pressures.the surface temperature of the rads is also lower, giving increased comfort and "wonderful calmness"[as described on this site last year].
    we had to install a vaporstat in order to maintain these settings-the factory supplied pressuretol is just not accurate below 16 oz.
    needless to say your venting must be perfect to get the air out equally quickly on all steam lines at the start of each cycle.
    don't forget to skim all the oil out of the boiler.
    a good thermostat [rated for steam] completed our improvements and now this system[dating from 1885] works better than i ever remember in 60 years i have been here!
    lastly i must say that i would not have known what to do and in which order without information from dan's steam book, available from this site and from advice from the steam professionals who frequent "the wall" [one of whom may even live in your hometown] -so you have come to the right place.good luck--nbc

  • "Ditto" on Nicholas' recommendations. Pressure wise: Lower`= Better(and cheaper-uses less fuel as it doesn't need to build all that pressure) It's possible that the installer may have set your pressure high to try to overcome other problems in your system, like non working /absent main steam line vents. (ask me how I know this!)
    From what I've discovered there are a lot of homeowners (myself included) and service people who don't really understand how a one pipe steam system works. Dan's books and the gracious help from the steam pros on this board have really helped me to straighten out my system.
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