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counter flow with parallel flow/ can it be done?

newagedawn Member Posts: 586
he guys installing a 1 pipe steamer, after looking over the system, i am deciding to cut out the extra 40 feet of return to the boiler its only 10 ft away from the main and make one radiator counter flow and the other 2 rads keeping parallel flow. the counter flow does have the pitch and pipe size to handle the load, QUESTION should i pipe the counter flow to the header or into the return side of the equalizer like it normally is in a counter flow, all opinions welcome
"The bitter taste of a poor install lasts far longer than the JOY of the lowest price"


  • MilanD
    MilanD Member Posts: 1,159
    As long as it's to spec, you can mix and match parallel a d counterflow. I have that same setup. Just make sure it drips to return somewhere before the header.
    New England SteamWorks
  • clammy
    clammy Member Posts: 2,668
    I have a few counter flow under my belt and have found the easiest and fool proof no issue way of piping them .I do a drop headed for starters .On the existing main i put a elbow facing down with a tee on the bull side i attach my supply off the drop header the run side of the tee i drop down to well below the boilers return inlet and usually will downsize the drip with a reducing coupling never a bushing .I do this for however many counter flow mains there are .i drop them all down lower tie them together and pipe them back into the hartford loop .I ve used this method for many years where i got it from i have forgotten but i ve had fanastic luck w it much better then other methods i have used .I would caution that most counter flows don t like high pressure or wet steam and uninsulated piping in cold ambients but what steam system likes any of that .A small main vent at the end of the line will ease your rad vents work load and usually on counter flow its a 1/2 per ft pitch .Peace and good luck clammy
    R.A. Calmbacher L.L.C. HVAC
    NJ Master HVAC Lic.
    Mahwah, NJ
    Specializing in steam and hydronic heating
    EBEBRATT-Ed Member Posts: 10,328
    The water has to have a way to get back to the boiler and can't come back into the header. Drip the counter flow into another return near the boiler.

    You can pretty much mix and match anything and make it work as long as pipe sizes and pitch are correct.

    I have a job where 1/2 the building is 1 pipe and the other half is 2 pipe. Works like a champ
  • Danny Scully
    Danny Scully Member Posts: 1,329
    I did this one about a month back if it helps for reference @newagedawn. It’s for 1 radiator.
  • MarkS
    MarkS Member Posts: 75
    My home has three parallel flow and one counterflow main, so yes it can be done.
    1890 near-vapor one pipe steam system | Operating pressure: 0.25 oz | 607 sf EDR
    Midco LNB-250 Modulating Gas Burner | EcoSteam ES-50 modulating controls | 70 to 300 MBH |
    3009 sf | 3 floors | 14 radiators | Utica SFE boiler | 4 mains, 135 ft | Gorton & B&J Big Mouth vents