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Drain for mini split condensate question

Hello everyone. I may at some point want to install a mini split on an interior wall in our house. Right now the wall behind it is open so I'd like take the opportunity to put in the necessary drainage whether I end up installing one or not. For those of you who install mini splits, what would you like to see in the wall to drain the condensate?


  • Ironman
    Ironman Member Posts: 7,379
    The corrugated tubing made for mini splits or PVC. Make sure it has continuous grade with no sags or saddles.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • ratio
    ratio Member Posts: 3,649
    The only real issue that I've had come up is the connection between the flex hose of the split and the drain pipe itself. It's always shady enough that I'd reeeeeaaaaallly like it to be accessible, but for some reason people never seem to want to have an access door under their wall tumor.
  • GW
    GW Member Posts: 4,700
    Yes when you bury the lines you're adding levels of grief. What's the plan with the line sets? I personally like to have the ability to remove the wall unit from the wall
    Gary Wilson
    Wilson Services, Inc
    Northampton, MA
    JUGHNE Member Posts: 11,075
    A removable panel on the back side of the wall unit would be good for future install/maintenance.
    I take the cond drain to daylight so it can be checked and back flushed. If far from a utility room or floor drain, I go with good slope between floor joists and out thru the rim joist to daylight.
    That drain outlet is one thing you want to get a visual on. Not only that the water is going where it should but is a good indicator of performance of any AC system. The key to comfort IMO.
    EBEBRATT-Ed Member Posts: 15,613
    all good suggestions I love the" Wall Tumor" comment by @ratio just guessing he's not a big fan of ductless splits. Like @Ironman said no sags in the piping double trap will not drain.
  • ratio
    ratio Member Posts: 3,649
    All the mfgrs are like "Goes with all decor! Looks great everywhere" & I'm like "Meh. You have a growth on your wall the size of a small trash can. Why didn't you go ceiling cassette, or ducted even?"

    Some of the new minisplit condensate pumps can be forced into the wall unit itself. That lends to a cleaner install

  • BigErl
    BigErl Member Posts: 38
    Thanks for all the responses. Like I said in my original post I may or may not end up doing this. For now I'll just put a coil of the corrugated tubing that Ironman suggested in the wall and run it into a closet on the floor below. From there I can run pvc to a drain in the basement. GW, my plan for the line sets and electrical was to drop them in the wall from above. It's an open crawl space so maybe I'll look into ceiling cassettes as Ratio mentioned. Anyway thanks again for taking the time to respond.