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Line-set length of minisplit

joenorm | Posted in General Questions on

I am wondering if the length of the line-set has any bearing on performance of a mini split?

Single-head Mitsubishi Hyper-heat 18K

The max length I would run the line is about 25ft, not a lot I know. But I could make it even shorter if it was better for the unit?


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  1. Yupster | | #1

    25' is the standard lineset length, it will have no effect on the rated performance. 40' causes a 2.3% reduction in heating on a FH18NA. What really matters is measuring the refrigerant charge for your INSTALLED length, not a guesstimate.

  2. joenorm | | #2

    I'm pushing 35-40 feet where I have it planned. I could shift it to reduce this to around 25feet.

    Is it worth moving for any gained efficiency?

    1. Yupster | | #3

      I guess that depends on if you think 2.3% is worth it. :) I would place it where it works best aesthetically & mechanically (sheltered from snow, minimum clearances, noise, drained condensate, etc.) and not worry about the small efficiency hit.

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