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Will Flex Seal Paste be the best solution for my condensate drain?

cbowner Member Posts: 4
Hi, North of Boston homeowner here.
My new high efficiency furnace drains to an old unused washtub. The HVAC company used liquid Flex Seal on the entire led drain pipe. The Flex Seal spray/liquid stopped the leak in the middle of the pipe, but the spray was sparingly used at the top of the pipe while too liberally used in the bottom of the cracked wash tub - it did not dry by the time crew left - then many hours later I scraped out the excess. I think Flex Seal Paste if it had been applied at the top of the pipe might have had a chance. The leak is a drip.

The alternative is to run the tubing to the 1st floor laundry room which is above an outer basement room that leads to the outside/gets colder than the main basement containing the furnace.

P.S. if you have used both the liquid and the paste - is the paste as strong smelling? I could smell the Flex Seal from the 2nd floor, so ran to the basement and had them keep open the door to the outside. They are used to fumes. I went to bed with my throat affected even after airing the house.

Thanks for reading this/any responses.

Before pics of wash tub and top of pipe.


    HVACNUT Member Posts: 4,355
    Because an HVAC contractor is actually using Flex Seal to repair a drain, my question is, did the contractor install a neutralizer for the condensate?
  • Motorapido
    Motorapido Member Posts: 268
    Hmm. My tankless water heater has a condensate tube that empties into a nearby, ancient basement laundry sink. Should I be concerned about the PH on that condensate, and neutralizing it? Never thought about this until reading HVACNUT's comment, above. Thoughts?
  • HomerJSmith
    HomerJSmith Member Posts: 1,419
  • SuperTech
    SuperTech Member Posts: 1,719
    If those are the pictures before the flex seal, I'd like to see the after pictures.  I had to repair a 3/4" typle L pipe that had a barely holding temporary flex tape repair last week.  
  • cbowner
    cbowner Member Posts: 4
    Yes, the HVAC company installed a neutralizer.
    JUGHNE Member Posts: 9,295
    Have you considered a new sink?
    Possibly just under the puddled concrete on the floor there might be cast iron drain piping....maybe galvanized pipe.

    Or with the sink gone then you might be able to just have a drain line with a trap. A forbidden-illegal "S" trap....the typical DIY plumbing install would suffice. There are hundreds of them in use. The worst thing is they might lose their water seal and pass sewer gas. Your furnace and AC (if there) would keep the trap primed.....(waiting for the blowback on the "S" trap). :|
  • Intplm.
    Intplm. Member Posts: 1,343
    Oh the flex seal craze. No doubt it has it place of use. I haven't tried it yet.

    What I have done is use something called propoxy, pictured here.
    It works quite well for what you are trying to do. Read and follow the directions carefully. This stuff really works short of changing the laundry tub, or installing this drain to a different drain or pump, which would be ideal.
    Good luck with the propoxy. It should do what you need.
  • 426hemi
    426hemi Member Posts: 75
    Flexseal seriously all I can say is wow