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Main Vent suggestions needed

Hello, I am looking for main venting advice on my steam mains. I have a Crown Boiler 135 BTU. The main line is just over 50ft long. The main vent is about 5ft before the last riser (makes no sense why it is there). Not sure why the original main vent was not at the end of the main. When I first moved in, the existing main vent was a small hoffman that was probably 30 years old. That was locked up and not even working. After reading on heating help, I installed a Gorton #2. That is the only main venting for the whole 1 pipe steam system. The last radiator on the main, never really get warm, unless the system is running all night long on a very cold night. I included a diagram. Coming left off the main header is the 50 ft main in yellow. The other steam main goes right to a couple of small rads and loops back into the boiler through a dry return. I indicated in the diagram where I was considering putting in additional venting. This is indicated in red. Looking for good advice. Thank you!


  • Jamie Hall
    Jamie Hall Member Posts: 22,891
    Let's concentrate on those "dry returns". Do they connect to the boiler? If so, how? Do they connect to each other and then drop to the boiler below the water line? Do they drop individually below the waterline and then connect to the boiler>
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 7,511
    edited September 2023
    It won't hurt to put those in. You can never have too many vents. I believe it will actually help. You should not put the vent at the very end. The vent should be at least a foot from the elbow that turns down to the return. It should also be on a small riser, do not put the vent directly into the tee fitting. here is a video that may help in deciding where to place the vents in your system. https://www.youtube.com/watch?v=VR6u_71FKGU.

    Take a special note during this explanation of why you should not put vent in a tee fitting at the end of the main
    Further in the video thare is this picture with the main vent 18" from the end of the main and it is in a on a pipe, not directly in the tee fitting.

    By the way, I think you need to pay your art director a little more, or at least the Graphics designer should be commended for such great work!

    Click on Spoiler

    Edward F Young. Retired HVAC ContractorSpecialized in Residential Oil Burner and Hydronics
  • bergensteamguy
    bergensteamguy Member Posts: 56
    Hi Jamie, great question. The dry return off the main drops down individually and goes towards the boiler. The other dry return also drops down from the ceiling and connects to the other dry return on a 'T' fitting just before the Hartford Loop. So they both connect below the water line of the boiler about 3 inches from the bottom of the Hartford Loop.
  • bergensteamguy
    bergensteamguy Member Posts: 56
    Hi Edtheheaterman, yes I was aware of those points. Thank you for bringing that up, because it is super important. Appreciate the response.
  • bergensteamguy
    bergensteamguy Member Posts: 56
    @Jamie Hall Thanks for your input. Let me know if you have any suggestions. The two dry returns drop individually and connect below the water line.