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Any info on SDR-11.5 tube

I was called out on a snowmelt job with some broken tubes. After opening the concrete the tubibg appears to be 1/2" tube. The only printing on the tube says SDR 11.5 tube. Is this the old Quest tubing. Or is this a metric Tube?  Could I use a conventional SDR-9 compliant conpression coupling to repair?  Thanks, Gary


  • hot_rod
    hot_rod Member Posts: 21,878

    Standard Dimension Ratio has to do with the wall thickness. If you are using a compression, external coupling then the OD is the question. Some times the tube would say CTS for Copper Tube Size. If so the OD should match copper tube 5/8, 7/8, etc. If you want to use an insert fitting it may not work.

    Is it grey PB tube? Should have a brand name on it.

    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • Gary Jansen_4
    Gary Jansen_4 Member Posts: 77
    Hey Hot Rod, guess what!

    A little more investigation and the mystery has been solved. The inability of the hospital to give me the original installer's name, the tubing app 1/4" to 2" below the concrete surface, the 170degree water flowing through the tubing off the steam boiler condensate line, and finally after I identified the tube as IRRIGATION tubing from Menards(an exact match, including the brass insert fittings and hose clamps we found buried). The hospital maintenance staff designed (?) and installed their own snowmelt!

    The tubing was crushed in spots from the truck traffic going to the loading dock. Like I was told- "it don't take no brain surgeon to lay tubin! "
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