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Can this much vacuum suck the pigtail dry?

I've had some drama with my instrument cluster lately. After throwing out a Wika LP gauge I rebuilt the piping, following some suggestions from other posts. First of all, does this all look ok? Second, as you can see from the PSI gauge, when the cycle ends it holds a vacuum for a long time. Can this suck the pigtails dry? Could it be damaging the gauges? It has been suggested I get snubbers.....


  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,578
    edited February 2012
    prolonged vacuum?

    i don't think the pigtails would lose their prime unless there were a leak to atmosphere on the gauge/control side of the pigtail. there should not be a prolonged vacuum in the boiler below an ounce or two. the main vents should allow air back in, unless they are not cooling off quickly enough on their antlers to open up. see if unscrewing one of them relieves the vacuum [boiler off after a long steaming]. a few ounces of vacuum may remain briefly in the gauge tree which is held there by the weight of the water in the loop. have a look at my tree and you will see that i have more interconnection at the top, which should prevent a plug in one pigtail from being a problem. note the shelf bracket which keeps it level.--nbc 

    this is an old picture, and now everything is above the top of the boiler, with more unions, but the principal is the same.
  • MotownSteamer
    MotownSteamer Member Posts: 110
    Uh oh....

    it's been over an hour since my post, and there is still a little vacuum on the dial! My system has one Barnes and Jones quick vent. I thought it was doing a good job, but if it is not cooling quick enough (and opening back up), should I add more or move it farther away from the dry return line?
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