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frozen pex in concrete

I had contractor come and hook up my in floor heat in my shop and he managed to mess my boiler up by pressurizing a open system. My boiler is down and he injected anti freeze in the system but thinks the lines in the floor could be frozen. Is it possible to thaw the lines or am I s.o.l this winter. Thanks


  • GordyGordy Member Posts: 7,106

    are all loops frozen if there is multiple loops?

    how does he know they are frozen? he must not have done a very good job injecting glycol in  the system.

    bring in alternative heat source to heat the garage a few days, and hope the pex did not burst if so you could be sol.

    so what malfunctioned in the boiler?

    what type of boiler is it?
  • natemannateman Member Posts: 3
    picked the wrong contractor

    There is 5 zones. Its a Johnson wood boiler. Its a open system boiler and he tried to pressurize the system to purge the lines and it blew the pins in the back of the boiler.
  • natemannateman Member Posts: 3
    anti freeze

    I'm not sure if the anti freeze made it all the way through the lines.
  • WeezboWeezbo Member Posts: 6,232
    two choices

    bang in like 100 X the heat loss btuh into the building ,

    or dash out and buy some hydraulic break line and lash it up to a purge pump and feed it thru one loop on each header at a time and connect them to heat with some amount of anti freeze keep doing that and the loops will help thaw out the near by loops as you work on getting the other loops thawed and purged out one by one ..


    or find someone who has the tools to do basically either or both of the above ..

    thats the fastest two methods i know .

    *~//: )
  • hot rodhot rod Member Posts: 7,014
    glycol in an open system?

    is the boiler separated from the radiant with a heat exchanger? Glycol will not last long in an open system.

    If the loop hasn't been frozen for a long period, you might warm the slab enough with loops that are flowing. if the entire system has frozen you could have some split tubing.

    The sooner you warm it up the better.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    The magic is in hydronics, and hydronics is in me
  • kcoppkcopp Member Posts: 2,748
    I know a....

    while back someone posted some pix of a set up they took a few rubber hoses laid thme on the frozen slab, covered them w/ InsulTarp, and ran heated water through the hoses.. This drove the heat into the slab. Less than a day later it was thawed.

    You are racing against time here. If you don't fix it soon you will have to break out the jackhammer to repair.
  • hot rodhot rod Member Posts: 7,014
    a homeowner thawed

    a frozen snowmelt by putting several hundred feet of garden hose on the driveway, covering it with poly tarps. My former company connected it to the boiler with a plate HX and thawed the frozen lines.

    It was a rubber tube system as I recall, so no freeze damage.

    I'll bet it could be tented with tarps and put a large LP or oil fired salamander underneath, carefully!
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    The magic is in hydronics, and hydronics is in me
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