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how much venting

bubbad Member Posts: 15
first timer,i have 11/4 main running 27' from header to furthest rad,it goes up to rad,throuh a t the t reduces int a 3/4 -28' return what size main vent would I need. never had mains before,i don't want to fix what ain't broke but I keep thinking effiecieny,would addind mains improve my small system


  • Fred
    Fred Member Posts: 8,542
    Is this a 1 pipe steam system? 1-1/4 inch main is really small. How many radiators are fed off of this main? Are there vents on the radiators? Do they all heat? If it is a 1 pipe and the rads are vented, I'd put 1 Gorton #2 on the end of that main, if you have the head room to get it up there.
  • Mad Dog_2
    Mad Dog_2 Member Posts: 6,692
    Fred's right. In general, you should add enough main vents to purge The main trunk line in a 5-10 minutes from an off cycle (most systems) Gerry Gill has a chart for exact capacities. Mad Dog
  • bubbad
    bubbad Member Posts: 15
    1 pipe system,no noises anywhere,installed heat timer adj.varivalves on all 6 rads.no banging,or surging in glass,new peerless 63/64 boiler,skimmed 3 x,no insulation,plan to insulate in next couple of weeks

    system appears to be running well would I still benefit from main venting,i had guessed at the gorton #2 as well

    I will add vents if you guys think it is helpful,

    from the hydronics inst,I calculate 210 edr