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Can ductless be slightly undersized for cooling load?

vernacubuild | Posted in Mechanicals on

An independent energy consultant calculated the cooling load for the first floor of my cottage at 13,778 BTUh. The heating load is 11,574. The first floor is 630 sqft, upstairs is 413 with a closed insulated crawlspace. The consultant said his calculations were conservative with the specific goal of not oversizing. I want to go with two mitsubishi hyperheat units, 12K down and 9K up.

The 12K hyperheat unit is rated for 12K BTUh of cooling. The next size up for hyperheat is the 18K unit. Will it be problematic if I go with the slightly undersized ductless for cooling?


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  1. GBA Editor
    Martin Holladay | | #1

    You have already asked that question. Here is a link to the page where you asked the question the first time; you'll find that your question has already been answered:

  2. vernacubuild | | #2

    Thanks, I got an error when posting the first one. I didn't think it was accepted.

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