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Spewing air check! What to do?

Gasper Member Posts: 148
Have a air check that is spewing steam.  It is on the top of a Webster air eliminator trap (shown in figure 12 and 14 of Lost Art, pages 237 and 239).  However the return trap is not there.  Do I replace the bad air check with a main air vent?  And is it possible that the air eliminator is bad?  Thanks


  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,576
    Webster system

    If this has suddenly happened, I would check the pressure, and verify it to be only a few ounces. Possibly the pigtail has plugged up, and caused the vaporstat to not feel the pressure.--NBC
  • Gasper
    Gasper Member Posts: 148
    New Boiler

    Just swapped out the boiler.  We installed the pressuretrol it came with to get up and running.  Will be swapping out w a vapor stat tomorrow.  However the old boiler just had a standard pressuretrol and it was not causing a problem.  Which has me confused....
  • JStar
    JStar Member Posts: 2,752

    Can you post pictures of the boiler piping?
  • Gasper
    Gasper Member Posts: 148
    Releasing steam not spewing water....my bad.

    Will try to post pics.  Tried once w no luck.  But it is pretty much piped like in the book EXCEPT the 1/2" horizontal pipe, that is connected to the air eliminator trap, on the left side, is capped.  Per the Lost Art drawing on pg 239 that 1/2" pipe should be connected to the top of the return trap.  The return trap is not there anymore.  BTW the air check is releasing steam, not spewing water.  I have to believe the air check is the main air release (vent) correct?  And if it's failed.....does anyone have experience repairing or replacing.?  Also if the return trap is missing what are the pitfalls?  The system was operating without it for some time.  Really appreciate any feedback.  Thank You!
  • Pumpguy
    Pumpguy Member Posts: 628
    What type of system...

    is this?  If it's a conventional 2 pipe system, you have one or more traps that are not holding and allowing steam to enter the return lines. 

    Lowering the steam pressure is always a good thing to do.  Even with a bad trap, a lower steam pressure will mean less steam blowing into the return lines. 
    Dennis Pataki. Former Service Manager and Heating Pump Product Manager for Nash Engineering Company. Phone: 1-888 853 9963
    Website: www.nashjenningspumps.com

    The first step in solving any problem is TO IDENTIFY THE PROBLEM.