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Odd Radiator Design

Harry_6Harry_6 Posts: 93Member
Someone recently sent me some photos of several radiators and asked if they could be used for two-pipe. Although I'd seen one or two of these in the past, I never gave it much thought. They are obviously hot water style, but with these odd featureless covers (?) where you'd expect to find a plug at the top. Although strangely star-shaped, there are plugs on the bottom, but what's the deal with the top? is there some kind of flush plug under the flat piece, or what?


  • FredFred Posts: 8,105Member
    Maybe designed to be drilled and tapped to the size of the supply pipe? The radiator in your third picture looks like it is cracked, up near the top plug/disc.
  • Jamie HallJamie Hall Posts: 11,464Member
    Or just possibly the seam around the flat "cover" is a deliberate weakness, and if you whack in the centre of that flat disc... you might still have to smooth the hole, and certainly would have to tap... I agree with @Fred on that third picture one. If it is cracked, it's junk -- so maybe have a go at that one?
    Br. Jamie, osb

    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England.

    Hoffman Equipped System (all original except boiler), Weil-Mclain 580, 2.75 gph Carlin, Vapourstat 0.5 -- 6.0 ounces per square inch
  • gerry gillgerry gill Posts: 2,960Member
    To answer your question, yes they can be used on two pipe, but the inlet and outlet would both be on the bottom. Its not as efficient as if the inlet is on the top.

    Serving Cleveland's eastern suburbs from Cleveland Heights down to Cuyahoga Falls.

  • SteamheadSteamhead Posts: 13,373Member
    Gerry is right. But if you can get them cheaply, go for it.
    All Steamed Up, Inc.
    "Reducing our country's energy consumption, one system at a time"
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    Baltimore, MD (USA) and consulting anywhere.
  • Harry_6Harry_6 Posts: 93Member
    I haven't seen these in person, so I'm not sure if that's a real crack or dirt in a scratch, but what do you think is the deal on that plug (?) near the scratch in particular? It looks like it has a screw slot in the center and some kind of shiny screw above that. And what good is a "hot water" style radiator if you can't use it for hot water? I agree that one could do two-pipe with both pipes on the bottom, but what did they expect you to use it for? And by the way, they look like they're made from dinosaur bones. Any idea what brand these are?
  • FredFred Posts: 8,105Member
    Most old cast iron hot water radiators can be used for either steam or hot water. Not all steam radiators can. These look like they can be used for either. The casting between each section appears to be an open channel on the ones we can see. That screw in the one unit is either where a bleed valve (hot water) or vent (steam might have been located
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