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

Separate run heat issues

alanm
alanm Member Posts: 71
Have an old steam heat one pipe system...two seperate runs....the one only goes to 3 radiators- one to the 3rd, 2nd and 1st floor. while other run gets radiators warm, this run will not...but when i remove the hoffman vent from that 3rd floor radiator, then all 3 on that run get warm...any suggestions. Also, seems that even if i do take off vent, if i am trying to increase heat by a few degrees, those 3 radiators will not get warm thanks

Comments

  • KC_Jones
    KC_Jones Member Posts: 5,737
    What main venting do you have in the basement? The way venting on steam works is to vent the mains first before any radiators start heating. After that the radiators can be addressed for venting.
    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
  • alanm
    alanm Member Posts: 71
    there are no main vents on the mains in the basement....there is one HOffman 40 vent but that is at the end of the run going back to the boiler area.
  • KC_Jones
    KC_Jones Member Posts: 5,737
    That's where you will need to start to balance things out. Either find were the main vents were and put them back, or might need to add a place for them. Sometimes the vent location is at the end of the overhead return piping were it turns down to the wet return, sometimes they are located after the last radiator before the return piping starts. There are various possible locations they could be. If you can't find any plugged holes then you will need to explore how and where to add them in.
    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
  • alanm
    alanm Member Posts: 71
    thanks....so taht Hoffman vent that is in the basement is at the end of the overhead return piping...that is only one in basement .....so i it seems i do have a main...but at the end
  • Jamie Hall
    Jamie Hall Member Posts: 23,276
    Since this is single pipe steam, and you have two mains -- the one with the vent and the problem child -- you need to have two main vents. Further, the "returns" (probably actually steam main extensions) much not be connected to each other before they drop down to the boiler return.

    What puzzles me however is that that problem riser doesn't work at all (none of the radiators heat?) unless you take the radiator vent for the top radiator off? That's a little odd. Usually, if a line isn't properly vented, but the radiators are, the radiators will heat, but perhaps not as well or not as fast. That this particular riser doesn't heat AT ALL, unless the top radiator vent is off, suggests that something else is going on with that riser.

    If you take the vent off the second floor radiator, do the first and second floor radiators work, but not the third? And likewise, if you take the vent off the first floor radiator, does only the first floor radiator work, but not the second and third?

    Some more detective work may be needed here.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • alanm
    alanm Member Posts: 71
    see photos...there seem to be two mains...one goes to the left (in the photo) does about 95% of the radiators...then the other main splits off to one radiator on the 1st floor (that gets hot) and then it proceeds to the 3 other radiators- 1st, 2nd and 3rd....as noted before, when i take vent off 3rd floor the other two get hot or if it is a big jump in temperate (say it is 70 and i go to 75) it will get hot. you see in photo...on the one return from the one main, there is a vent on the return . thanks