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 11-15 of 28 reviews

"Would not buy it again"

4.0 rating
Somewhat Satisfied

Unit installed by a diamond dealer in March 2014. March 2015, the unit was not heating. Unable to reach the dealer that installed it. Chat on Mitsubishi website indicated that the local dealer was no longer a diamond dealer. Was given the names of two dealers in our area. The new one we called checked it and said the compressor was bad but still under warranty. The bill including $100.00 for shipping of the compressor amounted to $724.00 plus the original $4,325.00. In December 2015 it started tripping the breaker. Local dealer checked it and said nothing was wrong but to call if it continued to be a problem. That weekend after tripping the breaker 11 times we shut it down. It was checked again by the dealer who could not find anything wrong. We turned it back on only to find all we had was cold air. Called the dealer back and was told they would check with Mitsubishi in the A.M. and get back to us. That was about 3 weeks ago and we have not heard anything. Sent an email to Mitsubishi with no return answer. It is my opinion that even the diamond dealers are not well trained in the operation and target shooting problems. Update (2016-05-09): Previous review indicated I had contacted Mitsubishi regarding our unit. They did get back to me. Our local dealer worked on it a couple times and then Mitsubishi sent a representative. He was very knowledgeable about the unit. He said he would be in contact with the engineers. Long story short they tried several other options and eventually replaced the outside unit. The problems were related to the cold weather so will be awhile to know if our problems are over. Mitsubishi worked with us and local dealer who was not the one who installed it. They did stand behind their product and we are very satisfied.

B Wood

Altoona, PA

"18,000 BTU heat pump"

1.0 rating
Very Unsatisfied

This is the worst A/C unit that I have ever own. I have two units in a house I built 5 years ago. The Mr. Slim has a problem with the condensate pump not working. Had to replace one. I noticed extensive corrosion in the indoor unit after the latest replacement. I'm still having a problem so I just use the unit for heating. On the condenser I had to replace a circuit board several years ago and now I have to do it again. The repairman wanted to replace all 3 boards. The boards cost nearly as much as a new condenser. The multiple city unit I had to replace one of the two evaporators since it rusted out (approx. $1500.00 in labor alone). I suspect the other will be going out soon. Would never buy anything with the Mitsubishi name on it. Oh, I didn't mention the thermostats and controls don't track to the temperature setting especially on heat. Don't no why. Then there is the problem that few repairmen really know much about them. So good luck getting someone good to work on them. Never again!

Dennis Strecker

Slidell, LA

"Very happy"

5.0 rating
Very Satisfied

We are extremely happy with our heat pump. It is the Mitsubishi Mr Slim. I would recommend, as it worked flawlessly through the worst winter we have ever seen. The A/C works great also. They installed it in an afternoon, did a neat and tidy job. I would recommend this unit, the Mitsubishi Mr. Slim 1200.


Summerside, Prince Edward Island, Canada

"Keeps me warm and cozy at night"

5.0 rating
Very Satisfied

I have owned this pump for over a year now and it has never let me down. It was easy to install but my son is a contractor so I guess that's kind of cheating. It's easy to use once installed and integrated, the only thing I don't like about it is that sometimes it would shut off before it reached the temperature that I thought was what I set it for but I really don't know. I have not had to have it repaired or replaced since I bought it but I have a warranty on it so I'm not too worried about that either. I would for sure buy the same model and brand again if I had the option. It does what it is supposed to do, nothing more, nothing less. My advice to people looking to get the best deal is to shop around online and see if any companies will price match or are willing to negotiate. When installing, make sure you do it correctly otherwise you could run into some major issues as I have read in some other online reviews.

Costa Mesa, CA

"MUZ-FE18 compressor failure"

1.0 rating
Very Unsatisfied

MSZ-FE18, MUZ-FE18 was installed in August/September of 2013 by a Mitsubishi Diamond Contractor. Had a problem a few months ago and after changing batteries, resting and power cycle unit, it worked. It just went out again and inside unit blinks 5 times. I had another Diamond dealer come out and they said the compressor is bad and labor is $1175.00 to replace the compressor. The dealer also said they have had a few failures of compressors after 6 months of the same unit that they had to eat the labor on. Mitsubishi should at least pay part of the cost of labor for this as the unit cost me $4800.00 to install 1-1/2 years ago.

Burton Crawford

Middletown, DE

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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