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Connect radiators?

Hello there,

I am thinking of connecting two steam radiators - is this possible?  It is a single pipe system.  Can you do this?  I have always wondered what that big nut on the other end of the radiator was for - can I take this out and connect a pipe to it?  The first one would be smaller than the other.  I would close the steam vent on the first and keep it open on the second...  I have two small rooms next to each other, and if I can connect to one radiator (which is already live), extend a pipe trough the wall, and connect a radiator at the other end, it seems like the easiest solution to get heat to that second room.  Any thoughts?  Thanks in advance!


  • Hap_Hazzard
    Hap_Hazzard Member Posts: 2,846
    The big nut

    is a plug. The hole it fills is there so they could assemble the sections when they made it.

    The problem with the approach you're describing is that you need to allow the condensate to drain from both radiators--not impossible, but very difficult. Also, the supply piping would need to be adequate for the total EDR. It's probably just enough for the radiator that's attached to it now.
    Just another DIYer | King of Prussia, PA
    1983(?) Peerless G-561-W-S | 3" drop header, CG400-1090, VXT-24
  • crash2009
    crash2009 Member Posts: 1,484
    edited October 2012
    Can be done

    First you want to check the size of your boiler to see if it can support the EDR that you all ready have plus the EDR you want to add.  Next check the size of your main line,  a 2" main can support 386 EDR.  Then check the size of the runout, from the main to the riser, a 1.25" runout can only support 55 EDR.  Next is the riser to the radiator, usually this one is no problem, a 1.25" riser can support 98 EDR.  Finally we get to the radiator, a 1.25" valve can support 55 EDR.  Here are a couple examples of how to connect another radiator to an existing one. 

    Lots of details huh?  These details and more can be viewed in a book sold here on the website.  The book is titled The Lost Art of Steam Heating (TLAOSH).  If you have a copy all ready check out pages 88-91 for more details.
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