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2 pipe system main vent???

I recently bought a house and believe the main vent is incorrect off the boiler... water shoots out of it, it is a Gortin no. 1... there are dole no.5's also on the system...can someone tell me which vent I need??? Thank you in advance!!!


  • Jamie Hall
    Jamie Hall Member Posts: 22,889
    One thing to check -- while you are assembling some more information. First, what pressure is your system operating at? It should be no than 1.8 psi cutout, and perhaps quite a bit less than that.

    Then... make sure this really is two pipe. Once you have done that, can you take some pictures of the piping in the vicinity of the boiler, and the boiler and its controls? That would help a lot. Also, how big, and how long, are the main steam pipes? And the general arrangement of the steam pipes and any dry returns (up high) and wet returns (down low). How are the hooked together?

    Water shooting out of a vent is not good -- but it's not the fault of the vent, and we will need the rest of that information to be able to help.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • thisch613
    thisch613 Member Posts: 2
    I believe there was a longer vent similar to the Dole no.5 in the pic where the Gorton is now, why someone changed it I'm not sure...
  • Steamhead
    Steamhead Member Posts: 16,714
    I'm assuming those are dry returns that the Gorton is mounted on. They come back pretty low. I bet you don't have enough "B" dimension for the pressure you're running, and the water is backing up into the vents.

    Change the pressure control to a Vaporstat, which cannot be set higher than a pound. Then upgrade the Doles to larger vents so the steam will distribute quickly at these low pressures. How long is each steam main, and what pipe size?
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service