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Leaking air vent

JPL941 Member Posts: 51
Hello everyone, I have a WMB-155c combi boiler. It had its annual service one day ago. Had a new zone installed, also had the air vent replaced because it was spewing water. 

Checked the boiler this morning, noticed water everywhere, couldn’t find a leak. Air vent seemed fine, saw a little residue but didn’t think much of it. Air out of system, tightened black cap. Checked system tonight, no water on the floor. Loosened black cap and water spewing everywhere. This air vent is not even 24 hours old. What’s going on with it? Is the inhibitor causing it to have issues? 

Please see attachment of air vent required by the system. 

Thank you! 


  • neilc
    neilc Member Posts: 2,171
    older system with cooties floating around in there?
    could be fouling the seal?
    or junk from adding the new zone?
    post a general picture , showing the air vent
    known to beat dead horses
  • Big Ed_4
    Big Ed_4 Member Posts: 2,124
    I just crack open the cap on float vents just enough to allow a slow bleed .

    There was an error rendering this rich post.

  • JPL941
    JPL941 Member Posts: 51
    Attached are requested pictures. Water that drained was relatively clear to the naked eye. Unit is only 2 years old except for vent which is 48 hours old.