Everywhere you look in Maine, contractors are installing minisplit heat pumps
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I’m concerned that most of the homes in Maine are not insulated properly for a air conditioning, vapor barrier on the inside of the wall. Is the cooling season in Maine so short and the delta t between inside and outside small enough not to be concerned about condensation in the wall cavity? Also I’ve spoken to several installers that have these in their own homes and say that they use them more for cooling than heating.
Thanks,
John
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Replies
We live in Maine. We used the A/C only about a half dozen days this summer. Our minisplits are mostly for heat.
John,
It's possible that some homes in Maine are heated with inexpensive natural gas boilers that were installed years ago. When such a home gets a ductless minisplit, the homeowners may use the minisplit for cooling and continue to use the boiler for heating.
If you are building a new home that will include air conditioning, it's a good idea to avoid installing interior polyethylene. If you live in an older home in Maine that already has interior polyethylene, I wouldn't worry too much. Absent any obvious evidence that the house has a moisture problem, it's perfectly OK to turn on an air conditioner to get you through Maine's rare hot spells. The possibility of a moisture problem in your walls due to interior polyethylene is quite low in Maine.