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Underground Steam return line repair. Please help

My underground (under the basement floor) steam return line is leaking.  The HVAC contractor says that he must dig up the basement (concrete) floor to find the leak and do the repair.  I am looking for alternatives to this costly and disruptive repair.  I am currently on disability and have limited income.  I do not need this.... Please advise with alternative... Maybe rerouting the return line or anything...


  • buried return leaking

    in most cases, the replacement return line can rest on blocks a couple of inches above the floor. the old line under the floor could be abandoned, and left in place.

    if there is no other route for it to take, the entire line should be replaced, especially underground.--nbc
  • jpf321
    jpf321 Member Posts: 1,568
    edited December 2009
    My re-routed underground return...

    Have a look at the following pictures .. this is what was done prior to my ownership .. to reroute the return from underground to aboveground.

    Old Near Boiler Return and Casing Cut

    Old Casing Cut and New above-ground return linkage

    Old underground return and new aboveground return (Return End)

    Please note that the old return pipe was probably only about 20ft long .. the new one is closer to 55ft long .. the new one is fully exposed above the basement floor and will allow me to notice any leaks and for me to feel the temp of the return throughout it's course. The new return does get hot (owie!), but not steam temperature hot (YEOWCH!).

    While he is at it, have him plumb a "gate valve" between the hartford loop and the return and a "full port ball valve" between the gate valve and return. Check for previous posts on this board regarding "cleaning return" or "flushing return" and you will understand why these parts are useful.

    There is probably no good reason to open up the floor and repair the current return. Mine does pass by an outside doorway, if you want pictures of how that was done, just let me know.

    I do believe that the returns should be insulated, so make sure there is ample space between the floor/wall and the pipe to get the insulation around .. mine is difficult in several spots.

    I hope this helps.
    1-pipe Homeowner - Queens, NYC

    NEW: SlantFin Intrepid TR-30 + Tankless + Riello 40-F5 @ 0.85gph | OLD: Fitzgibbons 402 boiler + Beckett "SR" Oil Gun @ 1.75gph

    installed: 0-20oz/si gauge | vaporstat | hour-meter | gortons on all rads | 1pc G#2 + 1pc G#1 on each of 2 mains

    Connected EDR load: 371 sf venting load: 2.95cfm vent capacity: 4.62cfm
    my NEW system pics | my OLD system pics
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