Need advice on mini-split location on second floor

July 5, 2017 9:19 AM

It's very hot on the second floor during the summer and I want to install a mini-split. The problem is that none of my exterior walls are in a shared space.

Have a look at my floorplan. Each bedroom has a ceiling fan.

An installer came today and the only solution he suggested was to install the mini-split head on the wall between the two bedrooms (in red on the floorplan) and run the cables and pipes through the two closets behind it. Then have the unit push air left and right (I believe the Mitsubishi FE12 allows you to push air in two directions at the same time).

Would there be a better location?

posted by kag to Home & Garden (4 answers total)

You'd be much better off getting a bigger outdoor unit and putting a wall cassette in each bedroom. The air will not be distributed evenly throughout the floor with only a single indoor unit, so you aren't really even solving the comfort issue you're having. It is an especially good idea in your case because as is the cool air will just go right down the stairwell, doing hardly anything for the bedrooms.
posted by wierdo at 9:41 AM on July 5, 2017

Huh? That makes no sense. You'd be paying to actively cool the only space where nobody sleeps or lives, and a stairwell. Just invest a little more to have this done properly: buy one shared compressor and install indoor units in each bedroom.
posted by halogen at 9:45 AM on July 5, 2017

Yeah, that stairwell will suck all the cool air down.
posted by intermod at 7:44 PM on July 5, 2017

Your installer is suggesting something you will not be happy with and makes no sense. Consider talking to someone else, that he would suggest this is a good idea either means he's not experienced or is happy to accommodate your idea without telling you it's bad because it's a paycheck.

Ac should generally be installed with the baseline standard of "one per room you want cooling in," whether that means a central ac with vents in rooms, Minisplits, window units, etc.

Your current set up will meaning the cooling will be limited to the hallway. You'll get a tiny bit of carryover into the other rooms if you leave the doors open all the time, get an oversized unit, and run the ac all the time, and even then it won't be enough. Window units in all the bedrooms would have better performance than the single minisplit in the hallway idea.

Could you clarify why you'd want only one, and specifically a minisplit?
posted by Karaage at 1:46 AM on July 6, 2017