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Main Vent Sizing

wsdave Member Posts: 97
Been quite some time since I've had to participate. A few years back, with LOTS of help from this site, I updated my near boiler piping, replaced my pressuretrol with a vaporstat and installed the Honeywell Visonpro t-stat. I must say the system is operating near perfection!
My question is about the installed main vents. I currently have 2 Hoffman 4A vents attached to one 15 ft 2" main and one 14 ft 2" main. Is the venting capacity adequate or should I look into installing Gordon #2 vents.
Thanks for taking the time to answer this question.


  • BobC
    BobC Member Posts: 5,470
    The 4a is pretty low capacity vent, I would replace each one with at least 2 Gorton #1's for each 4A. That would give you 5X the venting you have now. If you want to save some money use the Maid O Mist #1's instead.

    The Gorton #2 has over 3X the venting capacity of the #1 and costs about 3X as much. Using one Gorton #2 at each location would be great if your will to spring for it.

    You pay your money and makes your choice.

    Smith G8-3 with EZ Gas @ 90,000 BTU, Single pipe steam
    Vaporstat with a 12oz cut-out and 4oz cut-in
    3PSI gauge
  • wsdave
    wsdave Member Posts: 97
    Thanks Bob for the reply.
    I thought that the vents were too small resulting in unnecessary longer firing times.
    I'm going to get two Gordon #2 vents. Pricey - yes BUT you get what you pay for!!
    Thanks again.