Fujitsu mini-split - multiple single zone units vs. fewer, multi-zone units.
My first post after reading your site quite a bit in leading up to making a decision on cooling my home. Great advice here, I'm hoping to capitalize a bit further on it.
I'm in the process of having Fujitsu mini-splits installed in my home. Went with Fujitsu as it seemed the most responsive techs near me (NYC) were the Fujitsu installers and the units seemed to have a good reputation.
Mine is an old (almost 100) two family brick building without ducts, so I opted for mini-splits. Ironically, I'm now getting conflicting advice from my installer (the boss) and one of his techs.
The first floor is an open floor plan, and was easy peasy - put in a 24kBTU single zone unit. I had planned on putting in a multi-zone unit out back that would tend to the two bedrooms upstairs and the dining room downstairs (all relatively small, so we agreed that 9kBTU would suffice for each room).
The multi-zone unit that I had planned on initially was to save cost and keep from having units hanging off my house every ten feet (we're short on space here and the only place to hang 'em is up high over the first floor windows). It's on backorder, and while we're waiting for it the boss casually states 'I don't know why we're going multi-zone, it's less reliable'. The tech on the other hand said it'll be more efficient to run the multi-zone, take up less space, and save some money on installation (not a whole lot, they're charging me about as much to put up each evaporator as they did for the single unit that's up so far).
Anyone have any advice as to whether or not to avoid the multi-zone setup? I realize having one compressor would be a single point of failure, so if it goes out so do all the rooms that go with it. Is there anything about the complexity of the setup that should make me take a step back and go with a single zone setup?
And before anyone asks - yeah, these guys were the best of the bunch. NYC is like the wild west when it comes to hiring contractors of any type. By the time you sort out who's licensed, who's trained, who actually shows up when you call them - you don't have a long list of people left (in fact, you're lucky if you have ANYONE left sometimes). They did a good job on the one unit they installed, they were quick, it works well, and neat (the only things I can judge on, I don't know their job well enough to critique it otherwise). I just can't tell whether the boss is trying to get me to go with the single units because of the backorder or because he figures it's genuinely the better option.
Sorry for the long first post!
Should add - I have 5 rooms left that were going to get evaporators. Four bedrooms in the upstairs, and the dining room downstairs (which is part of that open floorplan but far enough away from the first floor unit that I figured it could use a little cooling). Each of the rooms is relatively small (ranging from 100-200 sq. ft.). I was thinking one multi-zone (9k x 3) in the back and another (12k x 2) in the front for the two larger bedrooms.