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Community and Q&A

Mini split lineset insulation disintegration

_jt | Posted in General Questions on

On one of my mini splits the “white lineset insulation” has basically disintegrated. (it feels like powder when I touch it) I spotted it by doing a thermal camera on the outside and I noticed I was leaking a decent amount off heat there.

What’s the recommended practice to prevent/repair this kind of problem? For now I have some neoprene left over from other projects that I’m wrapping the exposed parts in. The parts under a lineset cover seem fine, it’s just the small portion that’s not under a cover. (Maybe sun exposure?)


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  1. user-5946022 | | #1

    Interested in the response. I have the same issue.

  2. Expert Member
    BILL WICHERS | | #2

    Your lineset insulation sounds like it was damaged by ultraviolet light exposure. UV breaks down most plastics and you end up with a chalky, crumbly mess. The black pigment in some insulation helps with this, but if you have the white kind it would have likely broken down pretty quickly (maybe in just one season).

    You can buy split neoprene pipe insulation that you can use to re-insulate those lines. The orange store carries it in plumbing sizes, but for refrigeration tube sizes (which are a little different from the regular plumbing pipe sizes), you'll probably need to go to a commercial supply house. The black material will hold up better under UV exposure if there is no cover.


  3. 1869farmhouse | | #3

    My line sets are all tucked into secluded corners, so I just sprayed them with closed cell foam. On the flare fittings, I didn’t want direct contact so I covered them in rockwool and the sprayed over that.

  4. _jt | | #4

    That makes sense. Looks like there was direct sunlight no cover in that section. Probably should have at least taped it over - it all happened in one season.

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