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Homework Help: Opening the refrigerator door to cool a room.

  1. Aug 2, 2013 #1
    I'm well aware that the default answer to this textbook default question is "it doesn't work", but still, I believe it does.

    To cool the insides of the refrigerator, the compressor must do work, and since the efficiency isn't 100% you are constantly warming the whole room to cool it's insides, the winning move here is simply turning the refrigerator off. However, let's suppose it must stay on, wouldn't it be better to open the door?

    In other words: Isn't opened refrigerator turned on better than closed refrigerator turned on for the whole room temperature?
  2. jcsd
  3. Aug 2, 2013 #2


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    An open refrigerator will be an inefficient room heater. You'd need some method of venting the heated air from behind the refrigerator to outside the home to convert it into an inefficient air conditioner.
  4. Aug 2, 2013 #3
    Why would it be? That would be equivalent to putting a refrigerator compressor inside the fridge. Except that the whole room becomes an extension of the fridge.
  5. Aug 2, 2013 #4
    Right, indeed. I was also wrong about how a refrigerator works. It seems that the compressor regulates itself differently depending on the temperature, adjusting its work. That makes much more sense. Thanks.ks
  6. Aug 2, 2013 #5
    If I may suggest a different approach to your question. The key word in your question is the word 'belief'. What you want is to 'understand'. Therefore it's a good thing to take something as you have done that you 'know' goes against accepted knowledge and find fault with it.

    BUT, the thing is that you know you must be wrong but you cannot see it yet. What this does is highlight the areas of knowledge that you are unsure of. Because you know you are wrong the best course of action is to work from first principals and try to find where the error is. By asking for an answer immediately is like looking at the back of a book for the answers. It gives you answers but does not help you to understand, which is what you want to do.
  7. Aug 2, 2013 #6


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    If you don't mind drinking warm beer and eating spoiled food, go ahead, live a little, leave that stupid door open all the time.
  8. Aug 2, 2013 #7

    Andrew Mason

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    Even with a 100% efficient compressor you would be heating the room to cool the inside of the fridge.

    If you want to keep the room as cool as possible you should close the door. If the fridge is well insulated the compressor will not run much so you will not be putting much heat into the room. If you open the door the compressor runs and all of the energy it uses ends up as room heat.

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