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main vents heating evenly

alanm Member Posts: 40
i have a one pipe steam system (oil now, but was originally coal many many years ago!)- i do not have any vents on the pipes in the basementand all the lines are insulated in basement. There is a vent near the boiler, not sure what this is for. issue is we have problems heating all radiators evenly (some barely heat) and some that heat i am always taking out radiator vents and pouring out water. i attached photo of the vent near the boiler. what is my problem and what can be done to fix it.
- thanks
- Alan


  • alanm
    alanm Member Posts: 40
    one other thing i wanted to add- when i take off radiator vents, radiator gets alittle more warmer. thanks
  • Abracadabra
    Abracadabra Member Posts: 1,948
    *sigh*... what is it with people and copper on steam? :(

    Anyways.. sounds like you need more main venting if that is the only vent in the place.

    what pressure is your system achieving?

    what is the attached EDR? What is the rating of the boiler you have?
  • BobC
    BobC Member Posts: 5,182
    That vent is a Hoffman 75 do you know if it's working? Tell us how long your steam main(s) is and does the main have consistent slope along it's length?

    I agree that copper is not a good sign the boiler was properly installed.

    Smith G8-3 with EZ Gas @ 90,000 BTU, Single pipe steam
    Vaporstat with a 12oz cut-out and 4oz cut-in
    3PSI gauge
  • I see one dry return (with a main vent), but I don't see a second dry return. Can you tell us about that piping?
    What pressure is your system training. Some vents will close up when the pressure exceedes 3 psi. In your case, probably wet steam is temporarily plugging the radiator vents. What type are they?
    Each of those lines would benefit from at least one Gorton #2.
    If the second line is counter flow, then the vent will have to go on the end of that main, after the last radiator.--NBC
  • alanm
    alanm Member Posts: 40
    how can i tell/test if the Hoffman 75 vent is working? the boiler is a Crown Boiler installed in 2007. I have mostly hoffman adjustable vents on radiators. i was trying something and took off about 10 vents from radiators while heater was on, and only 3 (line right above the heater) were producing steam, where i had to put the radiator vent back on. the other radiator where vents are still off are getting warmer and no steam/water is cmoing out of them. thanks Alan
  • alanm
    alanm Member Posts: 40
    just checked. looks like main PSI is 2 and diff psi is 1.5
    if what i am looking at is right, there is about 65 linear feet of main piping (then branches off of this to the various radiators runing from 1st floor to 3rd floor).
  • KC_Jones
    KC_Jones Member Posts: 4,625
    If you have that much main then you are way under vented. If all that main is 2" pipe that would require at least 3 Gorton #2 vents. Rough rule of thumb is 1 Gorton #2 for every 20' of 2" pipe.
    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
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