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Misc. DIY reverse heat pump

  1. May 11, 2013 #1
    I don't know much about the subject, besides some diagrams and youtube vids, so please bear with me. I'm trying to make a reverse heat pump to cool a small room.

    If I had a heat reservoir (in a box within the same room) that could increase the temperature/pressure of a refrigerant and then used an expansion valve (restricting the flow of refrigerant) to decrease the pressure of the refrigerant, could I use the heat reservoir to evaporate the refrigerant sending cold air into the room?
    Last edited: May 11, 2013
  2. jcsd
  3. May 11, 2013 #2


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    If everything is in the room then all you can do is move heat around within the room.

    Sure you can devise a way to temporarily pump heat into this box BUT the inside of the box will get hotter and hotter making it harder and harder to pump it in there. In addition more and more energy will leak back out through the (insulated) walls of the box back into the room.

    Consider this question...

    It's a hot day. Will leaving the refridgerator door open cool the room? In the long term the answer is no. It will actually get hotter. The fridge will consume more electricity which represents more energy coming into the room. Opening the fridge door does not provide a new path for energy to leave the room - so there is a net increase in energy coming into the room.

    What you need to do is have one heat exchanger in the room and one outside the room.
  4. May 11, 2013 #3
    or in other words air conditioner. :D
    The ones work with the same thing you separate two places and to get the one colder you move the heat to the other , in the AC case the outside environment.
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