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Community and Q&A

One Multi-head Minisplit vs. Two Separate Units

ChrisStratton | Posted in Energy Efficiency and Durability on

We’re looking to build a cottage in western NH. We’re targeting about the minimum current insulation code (R30 for shed roof, etc). It is a one bedroom 875sf  design, but we plan to add a walkout basement for a second bedroom. Given that the July average temps are 82 F day/ 56F night, I am thinking to just put one 12K minisplit head in the bedroom upstairs and one 12k somewhere downstairs (which will be partially below grade). The glazing will mostly face to the East and the lot is pretty well wooded. What are the pros/cons to having one multi-head mini split versus two separate units?

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  1. Expert Member
    DCcontrarian | | #1

    One-to-one minisplits modulate better than multi-to-one, which means they do better at low levels. With two independent units if one fails you still have something. The downside is that one-to-one is somewhat more expensive and you have twice as much visual clutter outside.

    12K sounds like a lot for a bedroom. Like 2-3 times too big, especially in NH. Have you done a Manual J?

    1. ChrisStratton | | #2

      Thanks. No Manual J yet as still haven't gotten permit to build near poorly drained soils - so, haven't purchased the site plans. Thinking positive thoughts. Yes - likely oversized. Looking for both HEAT and cooling, hence 12k and leaving the door open. Might make more sense to put in open great room and leave door open for cooling the bedroom?

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