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steam control

i found an old johnsom heat control valve in an 100 year old church it was connected to a steam rad. The name on the valve says Johnson but in script in the middle of the valve it says Lylnhon valve Pat'd. any one know what this is for? there is a 1/4 inch copper tube coming off it and it sits onto of what looks like a rad valve. on the other side of the rad there is a 3/4 steam trap. it weigs about 5lbs and is about the same height as a coffee mug and a little wider. any help would be great.


  • Steamhead
    Steamhead Member Posts: 16,838
    That's actually a "Sylphon" valve

    which is (or was) operated by air pressure in that small copper line. Are there any other valves like that? Air compressor in basement? 
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
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