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Question on air vent capacity with reduced fitting attachment

DougP Member Posts: 13
Am I maxing out the venting capacity of the 1/2" pipe with a single BM and adding another was unnecessary ? After a few years of the single vents config I attached a backup extra to one side in January and felt like It made a difference, so I did it again.

also the ward reducing 45 street leg is a beautiful fitting


  • BobC
    BobC Member Posts: 5,479
    A half inch pipe can handle 4.8CFM at 3oz of pressure so it probably won't allow two BigMouths to vent completely but it will do better than a single B&J..

    Smith G8-3 with EZ Gas @ 90,000 BTU, Single pipe steam
    Vaporstat with a 12oz cut-out and 4oz cut-in
    3PSI gauge
  • SteamingatMohawk
    SteamingatMohawk Member Posts: 1,021
    Agreed, one B&J Big Mouth can pass 3.6CFM. I didn't see a number in the Pajak report, but found it on Amazon (I know, that's not necessarily the most reliable source, but the number seems reasonable).