Mitsubishi Mr. Slim Heat Pump Overview

The Mitsubishi Mr. Slim heat pump comes with a split ductless design. Mr. Slim offers up to 14.5 SEER and 8.2 HSPF when part of an indoor/outdoor system, and has a 2.5 to 3 ton capacity range. With a sound level as low as 26dB, Mr. Slim provides quiet, energy-efficient operation, along with effective zone heating. The M-series comes with a remote control which allows you to control the temperature, fan speed, and more. The remote also has a timer function.

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Consumer Reviews of Mitsubishi Mr. Slim


  • Very Satisfied
  • Somewhat Satisfied
  • Neutral
  • Somewhat Unsatisfied
  • Very Unsatisfied
  • #2 of 3 Mitsubishi Heat Pump
  • 35.71% of customers recommended

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Mitsubishi Mr. Slim Heat Pump Reviews

Showing 21-25 of 28 reviews

"Freezing in September!"

1.0 rating
Very Unsatisfied

It is currently 59 degrees inside. I put the unit on 1.5 hours ago and set it to 70 degrees. Well, it is still 59 degrees! The blower comes on every 10 minutes or so for 30 seconds and stops. This is how it ran all last year – barely affecting the temperature in the room! I have the heat mode selected, the fan at high and fan/vane set appropriately. I hate this thing! The floor is always cold (hard wood). Even in mildly cool temperatures it doesn't seem to be able to keep up, never mind when it's in the teens! Worst heating/cooling equipment I've encountered. Would not recommend this unit to anyone!


Eastern MA

"Parts hard to get"

2.0 rating
Somewhat Unsatisfied

Unit quit a little over 3 years. Hole in coil-no warranty. Replaced coil still didn't work. Needed compressor. Was covered by warranty but wrong compressor was delivered. Finally, after 4 mos. And $1800, unit is working again. Be aware you cannot order parts yourself. You must use a dealer. Small plastic clip on inside unit cover broke. The clip is small and pops out. I tried to order new clip but was told I had to replace the entire cover for $248. Can't order parts online. Check it out yourself. Mitsubishi only works through dealers.

S Politz

Brazil, IN

"Mr Slim"

1.0 rating
Very Unsatisfied

Bought 2 Mr Slims. A 12000 BTU, and a FE18000 BTU on 08/2013. My FE18000 gave great air conditioning for a month or two. When it got cold out, we ran it constantly, and it worked great until the temps dropped below freezing. My electric bills tripled and I was still running my furnace. After 5 months of service calls it finally quit. Mitsubishi put a new outside unit in.They had reprogrammed the inside unit to the old compressor with a tool that even they did not know what it would do. Finally, a letter came saying they were aware of a problem with the fe18 and would work with us on a resolution. 6 months later and they will not answer e-mails or return calls. I was told that there is a problem and a fix coming on all FE18s for 2 months now. Still no resolution. I believe that there are enough bad FE18s out there to warrant a class action lawsuit. Customer service says to get in touch with them.They forgot to tell you not to expect an answer.

Jim Evergates

Clinton MA

"Mitsubishi FE12na cold weather performance"

5.0 rating
Very Satisfied

I've had the Mitsubishi FE12na installed for only 2 weeks now but love it so far. 1600 sf bungalow. It has been able to keep 75% of the house at desired 22 deg c and the remaining distant rooms at 17 deg c at -22 c outdoor temps. Last night we had -16 with -32 windchill and it was producing 45 c air on Hi fan. I don't think I'll see -26 air temps this year to test it's lowest rated operating temp. Remember that as these units achieve better cold weather performance their over performance goes up as well including A/C.


Ottawa, Ontario

"Forth & coldest winter on Mr. Slim only."

5.0 rating
Very Satisfied

Installed in 2010, there are two msz-fe12 and a fe09 as the sole hvac in our 1500 ft. House located in central Missouri. With temps dropping as low as -12f in Jan 2014, I was shocked they handled the load to maintain 69-71f. No service required ever except to clean inside blower wheel and add cut Filtrette hammock media over the washable filters for better dust capture. Used about 1700kwh total in January with all electric utilities.


Lake of the Ozarks, MO USA

Other Mr. Slim Reviews

Comments on the Mr. Slim heat pump are generally positive. A consumer comment on stated that they supply minimal heat, but most other writers disagreed. A few other users complained about the price of the Mr. Slim heat pump, but almost all seemed pleased with the performance and quiet operation.

Mr. Slim Warranty

The Mitsubishi Mr. Slim heat pump comes with a 6-year limited warranty on the compressor and a 1-year limited warranty on parts.

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