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Community and Q&A

Do minisplits need to be winterized when off?

Bdgray | Posted in Mechanicals on

Hello all,

I have a Mitsubishi Hyperheat minisplit installed in a bonus room that is above our detached garage. 90% of the time the room is unoccupied. However I’ve been hesitant to turn it off over the winter out of fear any residual condensation might freeze and burst some part of the unit. I’m wondering if my fear is misguided. I certainly would prefer to turn the unit off and not heat an empty room for 4-5 months of the year.

If it matters, we live in Chicago.

Thank you,

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  1. Expert Member
    Dana Dorsett | | #1

    It's not going to burst from freezing condensation. It's more likely to suffer damage from defrost cycle icing if the pan heater fails. Where would the condensation be coming from? It will get far more moisture from rain or snow burial. If it's mounted in a way that it could possibly be buried in drifting snow put a cover over it, and dig it out when you need to use it. The cover would also protect it from rain (even though they tolerate rain quite well. If it's wall or rack mounted above the likely snow line and protected by roof overhangs (the way it always should be in snow country), forget about it- it'll be fine.

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