Question about Mitsubishi MS12TN Air Conditioner

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Heater!!! Unit acts like its heating but there is no hot air. Fan turns on, heat symbol is showing on the remote, but no heat

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  • Anonymous Nov 11, 2007

    igniter turns on so dose fan but no flam

  • latif Nov 13, 2007

    Ihave MR slim Mitsibushi ceiliing mounted but there is no heat coming from the unit and sometimes sign like p8 and E0 flashes in the LCD.please help. abi

  • Anonymous Nov 17, 2007


  • usmcs2007 Nov 21, 2007

    hi my name is fernando I work for a hotel in engineering department, my question or my problem is that the heat work sometimes but the next day is not blowing hot air only warm air what is the problem and we use this units with thermostast

  • Anonymous Dec 20, 2007

    on call for heat the fan won't start on auto the heat does not go pass the zone valve



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I am experiencing a similar problem with my Mitsubishi slimline MSH09TW unit; about 4 years old; It use to give us very hot air now it is giving some what hot air; northeastern USA current temperature about 15F. You think frigid weather in Cranbury NJ could be responsible or some thing else is going on. Please help me if you have some time and knowledge about Mitsubishi heat pumps. Sincerely, DSS

Posted on Feb 07, 2007


Thinking of purchasing, I browsed the mitsubishi slim web-site, and noticed they tout the A/C features. TV advertisements lead us to believe the units operate as regular ductwork heat exchangers that include a heating unit built into the exchanger. That does not seem to be the case as they suggest hooking the unit to your existing gas or electric heating unit, and also hook you up to purchase heating units.

Posted on Jul 16, 2008

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I have the same problem with my Amana PTH153B50AE . It runs with cool air come out but no heat. Can someone suggest anything wrong and what part I need to replace? It is very cold now in my room. Thank you very much.

Posted on Feb 19, 2007

Chances arre it is the high limit sensor L240F

Posted on Feb 15, 2007

I have the same problem. In heat mode air comes out at room temp, not heated. Unit is set to 72 degrees and room temp is 65. I have also tried setting the unit to 90 and still get not heat.

Posted on Jan 28, 2007

Room temperature

Posted on Jan 23, 2007

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Compressor is running just cold air now

Posted on Jan 13, 2007

  • loren heinz Jan 13, 2007

    very cold

  • loren heinz Jan 13, 2007

    warmed room up from 66 to 68 degrees then became cold


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Heats for about 10 minutes then becomes cold

Posted on Jan 13, 2007

  • loren heinz Jan 13, 2007

    electric heater heats for about 10 minutes then becomes cold

  • loren heinz Jan 13, 2007

    its cold


Check your fuses in outdoor disconnect or circuit breaker sounds like compressor is not coming on may be bad run capacitor

Posted on Dec 31, 2006

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Is the air coming out just room temp or is it "cold" air vice hot air?

Posted on Nov 10, 2006

  • Marc Wilson
    Marc Wilson Dec 31, 2006

    Sure, give a poor rating when more info is needed.... jezz people, we need more descriptions sometimes to offer suggestions on where to look. I guess their username should be a clue not to offer help huh?


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