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Community and Q&A

Minisplit lineset: Should it run through the attic or crawl space?

jserr68594 | Posted in Energy Efficiency and Durability on

My installer is willing to run the linesets in either the attic or crawl for my minisplit.

It will be more costly to run the linesets in the crawlspace and definitely easier to run them in the attic.

That aside, is one space better than the other to locate the lines?


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  1. GBA Editor
    Martin Holladay | | #1

    As long as the linesets are properly insulated (as required by the minisplit manufacturer), either location should work.

    Needless to say, if either your attic or crawl space is accessed by you or by contractors performing maintenance work, it's important that the linesets be installed in a location where they aren't subject to physical abuse.

    -- Martin Holladay

  2. jserr68594 | | #2

    So there is not too much efficiency loss by putting them up in the attic? If the difference in minimal, that will be the much easier way to go. Thanks.

  3. STEPHEN SHEEHY | | #3

    Justin: Just make sure to comply with manufacturer's instructions for maximum distance between inside and outdoor units.

  4. Anon3 | | #4

    Minimize hard 90 degree turns.

  5. Expert Member
    Dana Dorsett | | #5

    The amount of surface area of the line sets exposed to the attic are tiny, and heat gain/loss is quite small.

    Line sets need to be insulated primarily to avoid accumulating condensation / frost creating localized moisture problems- the thermal losses are a secondary issue, with only a tiny effect on system efficiency.

  6. jserr68594 | | #6

    Thanks everyone!

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