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Pressurization test

overpop Member Posts: 52
I have installed a boiler and I want to air test it before filling it with water. Does the Spirovent prevent pressurization or do I have to bypass this?

Thanks in advance...


  • Zman
    Zman Member Posts: 7,469
    The vent on the ones I have done will take a 1/2" cap
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • overpop
    overpop Member Posts: 52
    Yup, now I get why there are threads on top! Was wondering that. The pressure relief valve on the boiler says 30 psi, how much air psi can you give it to test?
  • ChrisJ
    ChrisJ Member Posts: 14,956
    Why not just go 5 PSI or so over what your operating pressure will be?
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • overpop
    overpop Member Posts: 52
    ChrisJ oddly thats exactly what my instinct said to do, so I put 20 psi in (at the moment bypassing the spirovent), it's holding and I will check it in the morning. Thanks for the advice! My first complete boiler install (plumbing & electrical) and it came out nice. Learned a bunch (Pumping Away), but what helped is that I used to install movie theater projection systems. High voltage, low voltage, heavy cast Iron and, in some installs there was a circulator pump that would pump water through the film gate to keep it cool. 35 mmFilm, running at 24 frames a second about 2 feet of film per second, would be warm as it exited the projector. The gate and trap had to be cooled or the film would buckle and focus problems would occur.
    JUGHNE Member Posts: 10,798
    I spent many years in a projector booth. Never had the luxury of water cooled apertures, maybe on a combo 70/35 projector that I might have been near occasionally. This was all carbon-arc light source and it would only melt film if it broke and was stuck in the gate. Now try that with old nitrate film and you might as well throw gas on it to put it out. Safety film was a great invention. The old projectionists claimed that nitrate has better color rendition than safety film, but they had older eyes/tastes. Color perception has changed in 50 years. The color of light bulbs is a good example, we have went from yellow to blue/white in preference.

    Just did the electrical/hvac in our new 67 seat one screen theater with digital & 3-D, surround sound with more speakers than we needed or paid for. Talk about a leap forward from our old 35 mm. Although we did have the late 1950's 3-D which was short lived, thank God.
    (Yes, we are a small town). My grandkids can not envision a theater with only one screen.