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Yes my friends another vent question

mgmine Member Posts: 58
I have another thread that got very convoluted and ended up with a vent issue. So here is hopefully a more straight forward question. I have two mains one is 58 feet long 2" pipe and two 90 degree bends. At the end of this run I have a Hoffman #75. When the boiler goes on the vent does puff somewhat but it doesn't really seem to send a lot of steam out. I'm not sure what to expect coming out of it.This vent last year was spitting water and did so until the installer skimmed the system. Could the vent have been damaged, can it be tested? And is this vent sufficient?

The other main is 56 feet long 2" pipe with five 90 degree bends.  The last 10 feet and the last 90 degree bend do not feed any radiators. The one that was on that branch was removed. This main has no vent on it only a pipe at the end of the last 10 feet that has been capped off .

What you would guys recommend that I install.


  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,576
    more venting needed

    i would start by adding a gorton #2 to each run, and watch your gauge [0-3 psi]as the cycle begins. the air should escape at a backpressure of no mnore than 2 ounces. if not then keep adding main vents until you achieve this.

    you will also be able to see what your pressure is, and it should be under 1.5 psi, for basic function; or under 6 ounces for economy.--nbc
  • crash2009
    crash2009 Member Posts: 1,484
    You could get started

     by building an antler, and using your existing vents.  Then, as things progress you can add more vents.  The union is optional but is nice to have.  Assembly can be done on the workbench, and just the union tightened while up the ladder.
  • David Nadle
    David Nadle Member Posts: 624
    Checking main vents

    I agree with the advice to add more vents, but I want to address your other question. If the vent is working properly there should be no steam at all coming out of it, only air. When the vent is cold it should be puffing, and when it's quiet it should be very hot. If it gets hot in less than 5 minutes or so you're doing OK. It is possible that your vents got damaged by the wet steam condition.
  • mgmine
    mgmine Member Posts: 58

    I guess I shoiuld have said that air is puffing out of the main vent not steam. When it is too hot to touch nothing is comning out. It was said " watch your gauge [0-3 psi]as the cycle begins" Does this mean the gauge on the  boiler? If so the pressure gauge doesn't seem to move much at all. If I add one Gorton in addition to the main that has the Hoffman on will that unbalance the other side if I only add one Gorton there as well?
  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,576
    watch the gauge

    you will need a 0-3 psi gauge, as the 0-30 psi gauge is useless for diagnosis, but must remain installed to alert you of imminent explosion.

    don't worry about having too much venting. the main vents should let all the air out with low back-pressure as quickly as possible. after they close they have no more effect. if you can hear any vents moving air, you need more.--nbc
This discussion has been closed.