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  1. #1
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    Mitsubishi H.I. SCM 45 ZF-S, dual, outdoor unit problem



    Hello everyone.

    The A/C doesn't heat. It starts ventilator and compressor. The pressure in heating is 12 bar (it doesn't move), current is 1,4 amps.
    This is the current situation.

    When I came and started the A/C it worked properly for about 15 min. The pressure was 30> bars, current 4-5 amps. And then presssure started to fall down.

    There is no led signaling on the outdoor unit.
    Signalisation on the indoor unit is:
    RUN - 1 blink every 6 or 7 seconds,
    TIMER - stays on

    First I changed the whole PCB of outdoor unit, didn't make difference.
    Then I changed EEVs, reactor, again nothing.

    When I replaced the whole outdoor unit, it started working properly.

    Is it compressor, and have can I check the compressor?



  2. #2
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    Re: Mitsubishi H.I. SCM 45 ZF-S, dual, outdoor unit problem

    Quote Originally Posted by for View Post
    When I replaced the whole outdoor unit, it started working properly.
    Problem solved then?

  3. #3
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    Re: Mitsubishi H.I. SCM 45 ZF-S, dual, outdoor unit problem

    No, I have to fix the defect one, the other outdoor unit was just for diagnosis

  4. #4
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    Re: Mitsubishi H.I. SCM 45 ZF-S, dual, outdoor unit problem

    either moisture causinga blockage or compressor - diagnosing a system when you cannot run it is a guessing game

  5. #5
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    Re: Mitsubishi H.I. SCM 45 ZF-S, dual, outdoor unit problem

    How can i check the compressor?

  6. #6
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    Re: Mitsubishi H.I. SCM 45 ZF-S, dual, outdoor unit problem

    http://www.lumelco.es/productos/pdf/...SCM-T-052).pdf
    only option is to refit faulty condenser and check for a temperature drop accross strainers and viewthe last saved data on the remote controller

  7. #7
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    Re: Mitsubishi H.I. SCM 45 ZF-S, dual, outdoor unit problem

    When the faulty was fitted, I saw frost on the exit pipe of the compressor . It lasted for 8-10 minutes. I think that compressor wasn't hot

  8. #8
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    Re: Mitsubishi H.I. SCM 45 ZF-S, dual, outdoor unit problem

    did you get the link for the service manual- blue text on post 6

  9. #9
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    Re: Mitsubishi H.I. SCM 45 ZF-S, dual, outdoor unit problem

    Yes I did. What part is prime for my problem?

  10. #10
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    Re: Mitsubishi H.I. SCM 45 ZF-S, dual, outdoor unit problem

    Is compressor in this A/C DC or AC?

  11. #11
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    Re: Mitsubishi H.I. SCM 45 ZF-S, dual, outdoor unit problem

    comp ac- part of the inverter circuit is dc, page 95 onwards gives fault diagnosis via indoor display leds and ideally a hard wired controller will give you an idea of whats happening

  12. #12
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    Re: Mitsubishi H.I. SCM 45 ZF-S, dual, outdoor unit problem

    Yes. But there's no explenation for my diagnosis: RUN BLINKS 1 TIME EVERY 7 SECONDS, TIMER STAYS ON.
    Anyway, I know that the problem is in the outside unit, but not in the electronics part. I can hear comp runing.
    Can it be that its runing futile?
    Can it be anything else except compressor?
    Can i check compresore presure?

  13. #13
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    Re: Mitsubishi H.I. SCM 45 ZF-S, dual, outdoor unit problem

    1 ON OFF E6
    Indoor heat
    exchanger sensor (1)
    error
    Broken heat exchanger sensor (1) wire, poor
    connection
    try shutting liq service valve to see if the comp will pump down- could be a faulty scroll comp- cant find any details to the make/type of compressor on the technical manual-
    there should be a common suction service valve- check suction pressure with it running and then after the 15mins to see if it drops, discharge press as you say should be around 30 bar, if the suction pressure drops due to a restriction then the discharge pressure would drop too, check the running temp of the compressor body- if its not pumping too well then it will start to overheat
    - if it drops then its a blockage if it stays the same at around 8 bar in cooling mode then its the comp not pumping

    to test the strainers for blockage- theres 2 on the liq line- inside the condenser,test inlet,outlet temps- if over 2 deg then thats your problem
    Last edited by install monkey; 11-01-2014 at 05:26 PM.

  14. #14
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    Re: Mitsubishi H.I. SCM 45 ZF-S, dual, outdoor unit problem

    Quote Originally Posted by for View Post
    When the faulty was fitted, I saw frost on the exit pipe of the compressor . It lasted for 8-10 minutes. I think that compressor wasn't hot
    Sorry about this I wrote wrong, it's the discharge pipe of the comp.

    Thank you very much for your tips!

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