candy fridge freezer cpc 240ffk

Discussion in 'General Electronics Chat' started by danielsweeney, Mar 25, 2006.

  1. danielsweeney

    Thread Starter New Member

    Mar 25, 2006
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    hi, people, can you help, need circuit diagram to repair fridge freezer because fridge is freezing up as well,think it is thermostat sensors but not sure. the model no is candy[cpc 240ffk].compressor and fan are running all the time and thermostat on inside of door has no effect.freezer works ok but over freezes and sensor attached to evaporater coils measures 0.5ohms when unit is off.
     
  2. n9352527

    AAC Fanatic!

    Oct 14, 2005
    1,198
    3
    You need a new thermostat. I don't think you'd need a circuit diagram, those fridge/freezers are very simple. The thermostat is in series with compressor, cutting the mains supply on and off.
     
  3. Gadget

    Distinguished Member

    Jan 10, 2006
    613
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    Could also be the door seals

    (Arf arf arf clap clap...... sorry, my impression of a seal has lost something in the translation)
     
  4. n9352527

    AAC Fanatic!

    Oct 14, 2005
    1,198
    3
    If it's the seal (not the arf arf arf clap clap kind :p) wouldn't the fridge get warm instead of freezing up?
     
  5. danielsweeney

    Thread Starter New Member

    Mar 25, 2006
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  6. danielsweeney

    Thread Starter New Member

    Mar 25, 2006
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    thanks for your reply.removed sensor attached to evaporator coil pipe[4-wire] yet compressor and fan still run,also removed sensor from PCB that hides at back of fridge rear side and still compressor and fan runs,so never worked on fridge circuits and need drawing to break down where fault is.Any typical fridge circuit would be great help.
    regards dan
     
  7. Erin G.

    Senior Member

    Mar 3, 2005
    167
    1
    The sensor attached the evaporator coil may very well be a TXV, or thermostatic expansion valve sensor, that is used to control the flow of refirdgerant through the coils. Are you sure that this device is electrical? If it is, is it a contact device that opens and closes? What does it turn on or off? As n9352527 said, these units are not terribly complicated, and you should be able to trace out the circuit. I've Googled all around and can't find drawing on any Candy products.

    If the seals on the door are bad, then you would be getting false warm temps to the thermostat. The stat would never shut off the compressor and eventually the unit would freeze as you described. However, the same thing will happen if you're low on refridgerant. These small units don't usually have service ports to hook up gages and see what's happening with the refidgerant, and that's really what needs to happen to get a clear picture of what the unit is up to. Here are a few comon things that you can check:

    Is the fan spinning in the correct direction? Usually the fan draws air through the evaporator and then across the motor/compressor.

    Is the evaporator coil clean and free from oil/dust? A fridge is a heat exchanger, and dust is an insulator.

    Is there any sign of an oil drip at any of the tube fittings or anywhere on the unit? If you do have a small leak, refridgerant oil may be visible somewhere.

    Is there a seperate fan that draws air from the freezer- into the fridge- compartment? Is it working? This little guy (if it exists on your unit) is usually well hidden behind the panels inside the unit, and may cause problems similar to what you've described.

    Good luck!

    erin
     
  8. Gadget

    Distinguished Member

    Jan 10, 2006
    613
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    Parts of the fridge would definately be warmer, and because of that the thermostat (depending on it's position) often keeps the fridge compressor running, resulting in the area around the cooling coils, or freezer box turning into a solid chunk of ice or "Freezing up".
     
  9. danielsweeney

    Thread Starter New Member

    Mar 25, 2006
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  10. danielsweeney

    Thread Starter New Member

    Mar 25, 2006
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    thanks erin for your reply and help.the txv sensor you mention is attached around one pipe of the evaporator coil and has 4 wires to PCB.not sure how it works but door seals are ok fan ok and no leaks, freezer works fine just overfreezes because fan and compressor keep going and cold migrates into fridge and back wall and bottom start to freeze as well.will take out PCB to draw circuit.
     
  11. dtiger2k

    Member

    Mar 29, 2006
    10
    0
    OK, figured I would throw in my two cents. Usually temperature control is controlled via a potentiometer. I would check to see that the potentiometer is ok. If it is the next step would be to follow it to the circuit and follow it through. You can do this with the sensor as well.

    Regards,
    Daniel
     
  12. danielsweeney

    Thread Starter New Member

    Mar 25, 2006
    7
    0
    thanks daniel have checked pot and is ok but 2 transistors on PCB have strange readings in circuit{ie] as if one section[diode] is faulty no reading[ohms] between two legs,need to remove pcb and draw out circuit.
    regards daniel S.
     
  13. scarter

    New Member

    Mar 31, 2006
    1
    0
    My Candy fridge freezer has just developed the same sympoms. If you manage to figure out what's wrong please post up your solution as it may help me!

    The seals on the fridge door have a couple of small tears in them - would this be enough to cause the over-freezing?
     
  14. Erin G.

    Senior Member

    Mar 3, 2005
    167
    1
    If it has wires coming out of it, then it is probably not a TXV (at least not one that I've ever heard of). The typical TXV has no wires: it's just a presurized line, and the presure changes with temp, and thereby opens and closes a reg valve that controls flow. Chances are what you're looking at may be a flow or temp sensor, and I can't tell you how it fits into the circuit without seeing it.

    Does the freezing start in the evaporator coils or closer to the compressor? Closer to the compressor may indicate a low charge, sans the indicative oil drip you looked for earlier. Is there any way to get a set of gages on your coils? How long between the time you start it up and the time it takes to start freezing?
     
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