Fujitsu vs. Mitsubishi Minisplits
My understanding has always been that Mitsubishi and Fujitsu ductless units are roughly comparable, though the Mitsubishi units are considered to have a slight edge in reliability and a larger distributor/service network in the US. I haven’t really paid much attention to the Fujitsu units’ specs since in my area there are way more Mitsubishi diamond contractors than there are Fujitsu elite contractors (or whatever they’re called). But I just started comparing the specs on some of the Fujitsu Halcyon units to the Mitsubishi h2i ones and I was surprised to learn that 1.) the Fujitsu units are notably more efficient (a COP of 5+ at 47F, compared to 4-4.5ish for the Mitsubishi units), and 2.) the Fujitsu units put out significantly more btu’s at low ambient temps than their Mitsubishi counterparts. Do I have this right? Am I missing something?
For example, the “9,000 btu” units. Here are some of the Fujitsu Halcyon specs:
Outdoor unit: AOUG09LZAS1
Indoor unit: ASUG09LZBS
Heating 5F max: 15,400
Heating 17F max: 16,000
Heating 47F rated: 12,000
Heating 47F max: 22,000
Heating 47F COP at rated output: 5.33
And here is the Mitsubishi h2i:
Outdoor unit: MUZ-FS09NA
Indoor unit: MSZ-FS09NA
Heating at 5F: 11,590
Heating at 17F: 14,170
Heating at 47F rated: 9,600
Heating at 47F max: 18,000
Heating 47F COP at rated output: 4.54
The Fujitsu unit has the Mitsubishi one beat in every single one of these categories. And they cost roughly the same (at least they do online). So what gives?
I find the 47F COP numbers particularly interesting. Because if the heat load for a cold climate, nine-month heating season house requires 25,000 kwh of electric resistance baseboard heat, and if the average temp in your area over those 9 months is at or close to 47F, then a rough estimate of your kwh usage by switching to either Fujitsu halcyon or Mitsubishi h2i 9k btu wall units would be 25,000/5.33 = 4,690 kwh (Fujitsu), or 25,000/4.54 = 5,507 kwh (Mitsubishi). This is not an insignificant difference, especially if you have high electric rates (20-30 cents per kwh in some areas).
So it would seem that if the above specs are what’s most important to you, Fujitsu is the obvious choice. Am I thinking about this correctly? Of course, it should be noted that the 9k Mitsubishi units modulate down to lower minimum outputs than the 9k Fujitsu ones – the Mitsubishi ones go down to significantly lower minimums than the Fujitsu units at all the benchmark temps: 5 F, 17F, 47F, 80F (cooling), and 95F (cooling). But if your loads at all these temps are not lower than the Fujitsu unit’s minimum output, then this wouldn’t matter, and the Fujitsu would still be the one to go with. No?
GBA Detail Library
A collection of one thousand construction details organized by climate and house part