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test ports on gas valve

zepfan
zepfan Member Posts: 397
Does anyone know where to get the fittings to check the pressures on these gas valves that have the very small test ports that you remove with a 3/32" allen wrench.The thread size is less then 1/16", and i can not find any thread by barbed fittings to check the incoming or manifold pressures.thanks to all.

Comments

  • Ironman
    Ironman Member Posts: 7,367
    There is no adaptor fitting. You simply slip the correct size hose over it with the screw open about 1 turn. :wink:
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
    Tinman
  • zepfan
    zepfan Member Posts: 397
    thanks,i'll do that
  • shawnnolan
    shawnnolan Member Posts: 7
    if its a female thread i use a 1/8" npt barbed fitting and push my manometer tube onto it
  • Ironman
    Ironman Member Posts: 7,367

    if its a female thread i use a 1/8" npt barbed fitting and push my manometer tube onto it

    Many gas valves manufactured in the last ten years don't have the 1/8" pipe tap. They simply have a tapered boss with a small screw inside. You open the screw about one turn to allow pressure to release around it and slip a hose directly over the boss. There is no adaptor needed. This is what the original question was about.

    I'm glad you're one of the few that actually checks manifold pressure. Most "techs" don't. Many don't even have a manometer or even know what one is.

    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
    icesailorshawnnolanTinman
  • Jpurdy647
    Jpurdy647 Member Posts: 11
    You are looking for this kit:

    Adapter Kit for 36G Gas Valves (link)

    Makes it way easier to put a hose on those fittings, they are a pain!!
  • ratio
    ratio Member Posts: 3,617
    The Fieldpiece dual port manometer comes with 'adapters' for that style of gas valve. Unless I miss my guess, it's nothing more fancy than a few 3" pieces of 3/8 tubing & a set of large <-> small plastic hose barb adapters. But I really like the Fieldpiece, especially the new model with the built-in pump. Kind of hoping my current one breaks so I have a reason to upgrade.
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 15,455
    Sigh, and I always thought a manometer had fluid in it!
  • GW
    GW Member Posts: 4,691
    edited January 2018
    When I convert Bryant furnaces to LP, I remove the 1/8” plug ( it’s a pain to get it out), I then spin in a nipple and 90 then finger tighten a barb fitting into the 90.

    The nipple/90/male by barb setup is nice and fast, I use it all the time
    Gary Wilson
    Wilson Services, Inc
    Northampton, MA
    gary@wilsonph.com
  • Tinman
    Tinman Member Posts: 2,808
    On mod cons, it's just like Ironman said. Loosen the screw just a little bit, put the boot of your manometer over the boss, and there's you have it. Quick and easy.
    Steve Minnich
  • Bob Harper
    Bob Harper Member Posts: 1,034
    http://www.maxitrol.com/miscellaneous.html
    As stated, more and more test ports cast into body of valve with captive screw. For inlet pressure, I use gas cocks with downstream 1/8" NPT plugged tap. Great for checking inlet pressure drop while firing.
    Tinman
  • Tinman
    Tinman Member Posts: 2,808

    Steve Minnich
  • JUGHNE
    JUGHNE Member Posts: 11,042
    I add a tee on the outside of the unit with a 1/4" branch after the gas stop. Put in a 1/4" brass plug. Keep a 1/4 x 1/8 bushing with the manometer to test gas pressure. Less things to take apart if checking inlet only.
    Easier than digging around on the gas valve.

    If you have ever had the Allen wrench strip out an aluminum plug it is a PIA.