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Community and Q&A

Mini Split Line sets

nickdefabrizio | Posted in GBA Pro Help on

I have read in several online forums that there have been problems with some of the white (polyethelene) insulated mini split linesets, namley that they corrode the copper tubing prematurely. Since I am in the process of having a new unit installed and have a white I-Cool lineset I plan to use, this piqued my interest. Has anyone else out there experienced premature failure of these linesets? 

Additionally , is there any real basis for running the lineset indoors to increase efficiency? I have heard different theories as to whether you can maximize efficiency running the sets indoors, particularly in cold climates. 


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  1. monkeyman9 | | #1

    I had been using the black insulated line sets and saw some corrosion but not holes. I've been using ICOOL white insulated line sets (inside of insulation is grey)....TBD. I'll have to look on my own. Now that I read up more I see some are caulking the ends. I'll have to try that. Some of the linesets say to tape the ends so air/moisture doesn't get it.

    I have seen some Mitsubishi indoor coils corroding on the copper 180 bends on the coils and have holes. There's a mix of aluminum fins, copper tube and steels supports on there. Happened more 7 years or so in. Not the best design with galvanic corrosion mixing the 3 metals.

  2. PAHighEffBldg | | #2

    I heard the same thing and when I looked at my 2 year old Mitsu heat pump line set, the white insulation was noticeably cracked and degrading. The copper line inside was showing signs of corrosion but still ok. I was installing a second heat pump and so the installer replaced the line set insulation on the first set as part of the second install.

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