Replies

1. GBA Editor
   Martin Holladay | Sep 07, 2012 10:01am | #1

   Chris,
   Anecdotal reports in New England (chiefly for Mitsubishi and Fujitsu units) are that installed units are performing well, with very few (if any) glitches or problems.

2. Expert Member
   Dana Dorsett | Sep 07, 2012 10:59am | #2

   n general, the experience & competence of the installer makes all the difference, but most vendors have good products, though support can be spotty for some. Fujitsu, Mitsubishi, & Daikin (not necessarily in that order) own something like 90% (a statistic made up on the spot :-) ) of the US market, but LG & Sanyo shouldn't be ignored. Look at the vendor websites for installer-certification programs, and their installer-finder . If you don't have at least a handful of installers registered with the manufacturer within 50 miles of your place you might consider a different vendor.

   They are remarkably similar under the hood, often with identical sub-assemblies (IIRC Fujitsu OEMs compressors and refrigerant valves to many vendors). They are highly evolved and actually much simplified beasts mechanically the "special sauce" affecting the relative efficiency is in the coil designs but more importantly, the control algorithms. Even with IDENTICAL hardware the control makes or breaks it on efficiency, and the complexity is all in the firmware/software.

   This is a very competitive market (it's the most-common heating & cooling system type in first-world Asia) and while bad designs & subcomponents DO exist (as with any heat pump or AC system) the major vendors can't afford the hit to their reputations and bottom line from many recalls and field failures. Mitsubishi has been building them for 40 odd years, and Fujitsu nearly as long. Daikin has some of the best-performing (and is a feature-innovator), with a very good reputation on overall quality. If you stick with those three, with a model that has been out there for awhile you should be OK, provided there is local distributor & installer support.

   There have been many thousands of them installed in the Pacific Northwest over the past 4 years under an NEEA pilot program- I suspect if the failure rates were high we would have gotten a hint. Most problems that I've been aware of (not that I'm an insider, just a close follower) have been installer error, primarily improper refrigerant charge leading to efficiency/capacity issues. If you dig through the related reports there is a treasure-trove of information on them:

   http://neea.org/search-results?q=ductless

   http://neea.org/resource-center/market-research-and-evaluation-reports

   They are remarkably similar under the hood, often with identical sub-assemblies (IIRC Fujitsu OEMs compressors and refrigerant valves to many vendors). They are highly evolved and actually much simplified beasts mechanically the "special sauce" affecting the relative efficiency is in the coil designs but more importantly, the control algorithms. Even with IDENTICAL hardware the control makes or breaks it on efficiency, and the complexity is all in the firmware/software.

   This is a very competitive market (it's the most-common heating & cooling system type in first-world Asia) and while bad designs & subcomponents DO exist (as with any heat pump or AC system) the major vendors can't afford the hit to their reputations and bottom line from many recalls and field failures. Mitsubishi has been building them for 40 odd years, and Fujitsu nearly as long. Daikin has some of the best-performing (and is a feature-innovator), with a very good reputation on overall quality. If you stick with those three, with a model that has been out there for awhile you should be OK, provided there is local distributor & installer support.

   There have been many thousands of them installed in the Pacific Northwest over the past 4 years under an NEEA pilot program- I suspect if the failure rates were high we would have gotten a hint. Most problems that I've been aware of (not that I'm an insider, just a close follower) have been installer error, primarily improper refrigerant charge leading to efficiency/capacity issues. If you dig through the related reports there is a treasure-trove of information on them:

   http://neea.org/search-results?q=ductless

   http://neea.org/resource-center/market-research-and-evaluation-reports

3. 
   gusfhb | Sep 07, 2012 05:47pm | #3

   I have personally approximately 11 unit/seasons with exactly zero[0] failures and exactly zero calls to customer support with mitsu mini splits.

   AC contractors make significantly less installing a minisplit unit than a standard ac unit, so, you do the math