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Vaporstat settings in vacuum system

Fizz
Fizz Member Posts: 547
in Strictly Steam
If running a system in vacuum what would be appropriate vaporstat settings?  How long does a system stay in vacuum?

Comments

  • Jamie Hall
    Jamie Hall Member Posts: 24,876
    As they say...

    your mileage may vary.  How long a system stays in vacuum depends on just how leaky the system is -- and what is creating the vacuum.  Obviously, if you have a vacuum pump on the system, it will stay in vacuum for as long as the pump runs!  Otherwise -- anywhere from as much as a minute or two, perhaps, to considerably longer for a really really tight system.



    Of course, you have to have vacuum tight vents...



    Since the system will eventually return to atmospheric pressure, I would not set the vapourstat to less than 6 ounces cut out with a 4 ounce differential.  Even that could be a little low, but if the 'stat is in good shape and properly calibrated it should work.  The check is that it must cut in above atmospheric pressure (0 psig) or you may find yourself in what looks like a lockout situation, but which is caused by the vapourstat not being able to reset.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England

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