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Main Venting

KayMacKayMac Posts: 12Member
I had my main vents upgraded 2 years ago and I believe they are Maid O Mist. I think the one closet to the boiler has failed already as it hisses the entire cycle. I am intrigued with the Big Mouth vents discussed on here and ready to order two if you can reassure me that they will fit on my system or let me know how to measure and purchase adapters. I have plenty of clearance in both locations (at least 6"). Thank you for your help.



  • SteamheadSteamhead Posts: 13,573Member
    How long are your mains, and what pipe size?
    All Steamed Up, Inc.
    "Reducing our country's energy consumption, one system at a time"
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    Baltimore, MD (USA) and consulting anywhere.
  • SailahSailah Posts: 822Member
    edited October 2016

    The big mouth is 4 3/4" tall that includes all the threads. So installed height is probably around 4.1/4" after you thread it in.

    The stock tailpiece is 3/4" npt. That's what amazon has. If you require a 1/2" tailpiece I can send you one. It will reduce the capacity of the big mouth a little because the opening is slightly smaller.

    You'll need a 5/8" allen wrench to install the stock tailpiece. Looks like you have at least 3/4" pipe there so it should easily fit.
    Peter Owens
  • KayMacKayMac Posts: 12Member
    I just placed the order on Amazon. I was going to replace the failed vent anyway and believe I needed to increase the venting there too. This seems like the perfect solution. Thank you!
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