Question about Mitsubishi Heating & Cooling

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Remote is inaccurate

We have a Mr Slim heating/cooling unit that we love except for one issue. The temperature on the remote is not close to the actual room temp. In other words if we set the remote temp to, say, 75 degrees, the room will only heat to 65 to 68 before the unit stops heating. Leaving it set like this maintains and even temp over many days, it is just that the temp on the remote does not come close to matching the temp of the room. It seems weird to have to set the remote to 75 degrees to get the room to warm to 66 to 68. Any suggestions or is there a way to calibrate the remote? Thanks!

Posted by W Taft on

  • 3 more comments 
  • W Taft Dec 07, 2013

    Also - We have tried resetting the remote.

  • W Taft Dec 07, 2013

    Now I have tried something to see if it helps. I'll describe and anyone with knowledge can tell me if it makes any sense.

  • W Taft Dec 07, 2013

    Right now the remote shows a set temp of 78 while the room is actually 67 degrees. I took the remote to another room where it can not communicate with the unit and used the arrow down button until the remote readout matche the room temp of 67 degrees. Then I took the remote back to the unit and arrowed up, (the unit responds with beeps), arrowed back up to 78 degrees. I will wait and see if that syced the remote and the unit and if the room temp now rises to match the remote.

  • W Taft Dec 07, 2013

    Well that did nothing. Room is still about 10 degrees cooler than rmote readout.

  • Anonymous Nov 24, 2015

    Hello. I realize this post is a couple years old, but wondering if you ever found a resolution. We are having the exact same issue. Room temp vs. remote temp is off by between 5 and 10 degrees.



1 Answer

Ahmad Alzurgi

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Did you change the batteries ?

Posted on Dec 07, 2013

  • 11 more comments 
  • W Taft Dec 07, 2013

    Yes we did.

  • Ahmad Alzurgi Dec 07, 2013

    The Thermostat is most likely not working well

  • W Taft Dec 08, 2013

    Don't think so. Noticed that it is not as big a difference when it is a bit warmer outside. Last night it got down to zero and the difference between the two readouts was 14 degrees this morning. Yesterday during the day it was 30 degrees and the two readouts were much closer.

  • Ahmad Alzurgi Dec 08, 2013

    The room should be closed well (isolated) , don't open doors and windows this should show a significant difference

  • Ahmad Alzurgi Dec 08, 2013

    what is the model of your Mr Slim unit

  • W Taft Dec 09, 2013

    The room is well isolated and insulated.

  • W Taft Dec 09, 2013

    And of course it is winter so doors and windows are closed!

  • W Taft Dec 09, 2013

    It is the MSZ series

  • W Taft Dec 09, 2013

    MSZ-FE12NA to be exact

  • Ahmad Alzurgi Dec 10, 2013

    High pressure protection :The compressor operational frequency is controlled by the temperature of the indoor heat exchanger to prevent the condensing pressure from increasing excessively. When the temperature of indoor heat exchanger becomes too high, the high pressure protection works. The indoor fan operates following the cold air prevention control. This mode continues until the temperature of indoor heat exchanger falls.

  • Ahmad Alzurgi Dec 10, 2013

    Maybe this is the case you have this may solve the problem

  • Ahmad Alzurgi Dec 10, 2013

    C:\Users\zurgi\Google Drive\Semester 131\460\Workshops\MSZ-FE09~12NA_Service_Manual_OBH542_7-27-09.pdf

  • Ahmad Alzurgi Dec 10, 2013



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