Click here to Find a Contractor in your area.
Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit

RFA re Venting

Emily718Emily718 Member Posts: 13
edited January 2016 in Strictly Steam
Hi everyone. I am a homeowner with an 1890s brick townhouse who is just starting to get familiar with our steam system. I am going to be installing insulation in the basement on the pipes (a topic on another post). I am also looking at the existing vents. Based on reading We Got Steam Heat, I believe we likely have insufficient venting on the mains, because the radiators hiss when the steam comes on. In the basement, we have two headers. The one to the front rads is 36 feet of 2" steel pipe (not including near boiler piping in the boiler room and 4.5 feet of pipe to a turn). At the end there is a single vent, slightly past where the wet return seems to drop out. The header to the back of the house is much shorter, 5-6 feet of the same 2" steel pipe after the L bracket turn (i.e., not including near boiler piping and 4.5 feet from boiler room to L bracket), with what looks like a capped area where the vent should be. Pictures are attached. Can anyone recommend the size of vents these pipes need? Is the venting in place on the long pipe sufficient? Shouldn't there be venting on the rear, shorter pipe? I am attaching photos I snapped yesterday while measuring for the insulation. Should there be additional venting on the pipes that branch out to the rads in different parts of the house?

I wanted to note that I called a person in my area who advertises as a steam heat expert and advised him by phone of the situation. He stated that it could be that the venting is sufficient and we should just check the vents on the rads. While I agree that we should check the vents on the rads (why not?), I find the comment that we may not need additional venting in the basement very surprising, based on what I have read in Dan's book and on this board. I thought it would make sense to get some advice from the experts here, rather than someone who may be a knucklehead.
Thanks in advance, everyone!


  • nicholas bonham-carternicholas bonham-carter Member Posts: 8,358
    Put 2 Gorton#2's on the long main, and put the smaller vent on the shorter one.--NBC
  • FredFred Member Posts: 8,503
    I agree with what Nick said.
  • New England SteamWorksNew England SteamWorks Member Posts: 1,397
    And I agree with what Fred said. Make sure you have a minimum 1/2" pipe nipple out of the main tee. Photo attached for one way to do it. You want to get the vents up and away from the steam main to protect them, preferably with a Y strainer.
    Plug for above
    Easy, and will make a big difference!

    New England SteamWorks
    Service, Installation, & Restoration of Steam Heating Systems
  • Emily718Emily718 Member Posts: 13
    This is so helpful. Now I need to find someone to do this in Brooklyn. Recommendations welcome!
  • Emily718Emily718 Member Posts: 13
    Would someone kindly confirm that this is the Gorton #2 we are talking about: (on Amazon for $91).
    I've seen these elsewhere for about $75 also. I want to make sure I am getting the correct item. Also, would it make sense to get a Gorton #2 for the back line as well?
  • FredFred Member Posts: 8,503
    Yes, that is the Gorton #2 we're talking about. Make sure you have at least 7" above the main to install it. On a one pipe system, Each main, front and/or back should have them to properly vent the mains and balance the system.
  • Emily718Emily718 Member Posts: 13
    Thank you Fred!

Leave a Comment

BoldItalicStrikethroughOrdered listUnordered list
Align leftAlign centerAlign rightToggle HTML viewToggle full pageToggle lights
Drop image/file


It looks like you're new here. If you want to get involved, click one of these buttons!