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Leaking radiant in slab

Dana Member Posts: 126
Find the leak and fix it.


  • Tom Sholl
    Tom Sholl Member Posts: 2

    I installed a hot water boiler with domestic coil to a radiant system in the concrete floor. Unfortunately, there is a slow leak in the floor. There is no basement or access to the piping. It also is about 45 years old. Is there a sealant available to mix with the water which won't impare the output of the hot water coil? I can run nearly zero pressure in the boiler as the radiant is below the boiler. The boiler does have a low water cutoff.

    Thank you
    Tom Sholl
    [email protected]
  • bull
    bull Member Posts: 2
    leak in slab

    Yes there are different addatives you can buy that may help the leak, but your best bet is to find the leak and fix it.
    Also I'm interested to find out what kind of tubing you have in your concrete that is 45 years old.
  • steve_6
    steve_6 Member Posts: 243
    it's probably copper

  • steve_6
    steve_6 Member Posts: 243
    how do you know its leaking?

    what room or rooms is the leak in?
  • Jackchips
    Jackchips Member Posts: 344
    My house

    had radiant installed in '68 with steel pipe and I used to have to pump quite a bit of sealer into it.. The system was installed by my late Father-in-Law and he ran it at 180. I put in a mixing valve in '75 when I moved in but it was to late. The system gave out along with the GE boiler in '80.
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