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Adding a Radiator to an existing one pipe steam system

Kat24 Member Posts: 1
I have a well insulated three season room that I am considering adding heat to to extend it's use through the winter.

On the opposite side of the wall adjoining the three season room is a steam radiator. I am wondering if it is ok to replace the current L joint to the existing radiator with a T joint, and then have a pipe added to run from the T joint through the wall to a new small radiator to heat the three season room? The additional piping run would be no more than 2' long. The three season room is approximately 200 sq feet. So in other words I'd have two radiators running off the same pipe.

I am researching ideas as this is a job I'd have to hire out. Which brings me to a second question -- who do I call to work on an older rad steam system? Is this a job for a plumber or should I be looking elsewhere?


  • Hap_Hazzard
    Hap_Hazzard Member Posts: 2,846
    The trouble with tees

    is that the pipes connected to both ends can't slant down towards the main, so your condensate won't be able to return quickly enough to get out of the way of the steam. Also, you'd be connecting two radiators to supply piping that was only intended for one.
    Just another DIYer | King of Prussia, PA
    1983(?) Peerless G-561-W-S | 3" drop header, CG400-1090, VXT-24
  • JStar
    JStar Member Posts: 2,752

    You should consult a steam pro. Where are you located? We may know somebody nearby.
  • Snowmelt
    Snowmelt Member Posts: 1,416

    Need a heating mechanical company.

    Here's one thought you the wet return and a S.S. Circulator and run a hydronic system in that room.

    Just a thought
  • BobC
    BobC Member Posts: 5,479
    If your really lucky

    And the radiator feed pipe is large enough to feed both radiators.

    And it can be piped so BOTH radiator feeds slope back towards the boiler.

    And the radiator is close to the boiler so you can add a drip to this pipe so you can increase it's steam carrying capacity and get rid of the pesky condensate.

    Or maybe you have to convert one or both those radiators to two pipe.

    Or maybe it would be easier to make the new radiator a hot water radiator.

    This may be more involved than you think so it would be best to have some expertise handy so it works like you want it to without having to do it again.

    Smith G8-3 with EZ Gas @ 90,000 BTU, Single pipe steam
    Vaporstat with a 12oz cut-out and 4oz cut-in
    3PSI gauge
  • Charlie from wmass
    Charlie from wmass Member Posts: 4,322
    yes you can add a radiator IF

    the run out is the right size, you can tie in to a location the condensate can drain to, the boiler has capacity to supply the added load. Some plumbers know steam.
    Cost is what you spend , value is what you get.

    cell # 413-841-6726
  • ExnihiloSteve
    ExnihiloSteve Member Posts: 1
    Came across this rather old thread and wondering how the orginal poster solved their problem, since it's EXACTLY the same thing I want to do.
  • Hap_Hazzard
    Hap_Hazzard Member Posts: 2,846
    The OP hasn't logged in since the site was migrated. There's a slim chance that they might get an email notification if you DMed them, but there's no guarantee they'll respond even if they do.
    Just another DIYer | King of Prussia, PA
    1983(?) Peerless G-561-W-S | 3" drop header, CG400-1090, VXT-24
  • dopey27177
    dopey27177 Member Posts: 887
    To really answer that question we would need to see a p9cture of what you are talking about.

    The best way to do this job is from below the floor of this room.
    Running two radiators off one supply line on a bull T is a no no.

  • AdmiralYoda
    AdmiralYoda Member Posts: 632
    @ExnihiloSteve in this application I think it would be best to install an oil filled electric baseboard sized appropriately for the heat loss of the room.

    Just needs electricity and it's own thermostat in the room.  It will be on its own zone.