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Community and Q&A

Request for Opinions on this Minisplit Plan

AtTheBeach | Posted in General Questions on

In another thread, I asked about backup systems as we switch to mini splits and determined the best choice for our needs is a small electric boiler. House is 20 yr old Canadian modular that was insulated to the point that it came with an air exchanger, about 1200 sq feet on main floor plus a walk-out basement level. Layout is attached. Zone 6 climate. Vacation home used mostly in summer and  fall.

My husband is worried about pipes freezing. Upstairs we’ll have a cassette in living room and in bedroom. I would think leaving doors open for air flow will keep the upstairs bathroom pipes from freezing?

Downstairs, one more cassette. It could be in the hallway but the doors to utility room & garage are typically shut, so no heated airflow to those spaces. There are hydronic heaters in utility room & garage (as there are in the rest of the house) which wouldn’t kick on unless the electric boiler backup came on. BUT downstairs is really a walk-out basement (with the walk-out being the front entry); the bathroom and utility room are built into the side of a rocky slope. Wouldn’t that protect them from a pipe-shattering freeze? I don’t care about the garage being freezing (no canned vegetables, no car stored there) – or should I since there is a hydronic baseboard heater?

I think mini splits with a small electric boiler backup would work, but the minisplit guy isn’t sure or husband is confusing him with questions… It should work, right?

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  1. creativedestruction | | #2

    Number and placement of thermostats? Agreed on the other points, if you have at least one centrally-located tstat per level, keep all the interior doors open and sink base cabinets open and you can rest easy.

  2. AtTheBeach | | #3

    There is a thermostat on each level, close to the bathroom door in both cases. So keep the door to Utility room open also?

    1. creativedestruction | | #4

      It should keep all room temps more equalized, so yes, utility room too. The heat won't run much set at 40 to 45 so you're not really saving much more energy by isolating any rooms. Uniform temps are safer unless you're absolutely certain of where every plumbing line runs.

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