Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.

air vent mystery

Hey everyone,

I installed 2 new additional air vents on my system and I am seeing odd behavior that I do not understand. There are 3 air vents in series, and the first and the last vent expel air, but the middle vent does seem to expel any air.

I will probably re-configure the antler, but I wish that I understood this phenomenon!

Thank you,


  • Fred
    Fred Member Posts: 8,542
    Is that antler pitched down? If so, it will hold water and before you know it, none of those vents will vent. If it is pitched down (and it's not just the way the picture was taken) turn the antler 180 degrees so that it pitches back to the riser.
    If it is pitched correctly, it is possible the middle vent, even though it's new, could be stuck closed.
    JUGHNE Member Posts: 11,061
    Your horizontal manifold must be set to drain back into the vertical riser. If you ceiling is near level it looks wrong. Turn the whole thing around to drain down.

    Could also be a defective vent. With them off, the G2 should rattle when shaken.....holding upright you should be able to blow thru them.....then when turning upside down the float should seal the vent and the air flow.

    Please let us know the cause.
  • rhodebump
    rhodebump Member Posts: 152
    Sorry but I held the camera off. It's level, but I can add a pitch to it. Good observation!
  • ethicalpaul
    ethicalpaul Member Posts: 5,702
    There might just not be enough volume to be able to feel airflow on all three.
    NJ Steam Homeowner. See my sight glass boiler videos: https://bit.ly/3sZW1el