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.

old one pipe heat system

pitbull Member Posts: 2
I need some help. I have an  old steam system that was converted to hot water some time ago. 1.5 " trunk line with 1.5 x 1 tees. Now in the return tee branch is a bushing that has a cone shaped scoop which when threaded into tee protrudes into trunk line. this scoop faces in the direction of flow so i believe it works by creating  low pressure and actually pulling water through return. My question is this if  i reverse the flow of water so scoops now catch passing water and push it up tee would this be more efficient . Right now  the baseboard on second floor do not get hot and they are feed off the very end of trunk line close to circulator . re-piping so return is feed would mean second floor would be first . but will water go up those crazy cones or would it just flow past as it would require more pressure to go up cone than to just flow past.


  • Alan (California Radiant) Forbes
    Venturi Tee

    That fitting was installed on the return side because the cooler water is more dense and less buoyant at that point and has greater pulling power.

    Yes, reversing the flow might work, but before doing that I would replace the tee on the supply side with a Venturi tee (also known as Monoflow tees).  Both, working in tandem should be able to get hot water up to that baseboard.
    8.33 lbs./gal. x 60 min./hr. x 20°ΔT = 10,000 BTU's/hour

    Two btu per sq ft for degree difference for a slab
  • pitbull
    pitbull Member Posts: 2

    thanks but i am only familiar with copper mono flow tees and the system is 1.5 black pipe  
  • JStar
    JStar Member Posts: 2,752

    How far apart are the supply and return tees for the upstairs radiators? They should be at least the width of the radiator apart, and may need to be more to create the necessary pressure difference.
This discussion has been closed.