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Two Pipes with Radiator Vents - Should I put traps in?

1dodson Member Posts: 13
I just bought a 1918 vintage house with a two pipe steam system.  It appears that a previous owner removed the traps and put air vents in all the radiators.  The system seems to work fine (ie everything gets hot and there are no major noises). 

Should I just leave well enough alone or would I get better efficiency by reverting back to traps and plugging the vents?


  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,575
    2-pipes and no traps

    there may have been metered orifices in those radiator valves, which would only let enough steam in to condense all of it in the radiator, at very low pressure. as the system was changed over the years, the pressure may have been raised, throwing this principle out of whack.

    why not post some pix of both ends of the radiator, and someone may recognize the parts, and their operation. let us know what your pressure is as well.--nbc
  • 1dodson
    1dodson Member Posts: 13
    No Orifices -- but that might be a good solution?

    I will post some pics this weekend but I took the inlet valve off and the outlet connection  and there is no orifice. So it seems to be a standard two pipe system, inlet with shutoff valve at the top of the radiator, outlet at the opposite side, no traps, and vents on the outlet side about halfway up the radiator.   I checked in the basement and there are vents in the mains and return.   

    Like I mentioned in my first post, everything gets hot but I am wondering if this is really the best arrangement for the system.  What does everyone think of an orifice system for a two pipe?  
  • 1dodson
    1dodson Member Posts: 13
    Pics - Maybe this is a pre-trap two pipe???

    Attached are some pics of my two pipe system.  The inlet pipe is 1" and the outlet is 3/4".   Some of the radiators have vents on both sides, but most have a single vent on the outlet side.

    Could this be a pre-trap two pipe system?   The house was built in 1918.  
  • Need more pictures

    Looks like a vapor system of some type.  You might want to take some more pictures up close of the inlet and outlet radiator fittings. Also look around near the boiler and take pictures of the near`boiler piping and any "weird" contraptions you find anywhere in the piping either near the boiler or located elsewhere.
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