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I How to move cool air down through a house?

  1. Jun 10, 2017 #1
    so I am trying to move cool air from my room on the third floor to the living room on the second floor, but it does not seem to be working as well as I would like it to. I have the windows open and fans pointing "in" upstairs while downstairs they are pointing "out". Do I need fans directing downstairs? thanks in advance.
     
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  3. Jun 10, 2017 #2

    mfb

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    Fans do not "suck in" air. They can only blow air in a specific direction, but this air comes from everywhere around them. Unless your fans upstairs are outside the window (or in the window and you close the rest of the window), they won't do much.

    How warm is it where? If there is a large temperature difference between the house and outside, convection can do the heat exchange on its own - but then you also get in hot air on both floors. A purely internal heat exchange could work as well - fans mixing the air at the staircase.
     
  4. Jun 10, 2017 #3
    so I do have the fans in the window, I live in aurora,co and it is suppose to get to 90 today. So it sounds like if I have powerful fans directing the air on the stairs down to the windows in the living room I may get some better results? thanks
     
  5. Jun 10, 2017 #4

    berkeman

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    Do you have a furnace and duct work running throughout the house? If so, you could re-purpose the duct work during the summer to route cool air by using blowers...
     
  6. Jun 10, 2017 #5
    Aurora is located in a high plains dessert - has low humidity. I have successfully used a swamp cooler that operates by adding moisture to the air. Locate a portable (Home Depot or Lowes) in an upstairs window and open a window on lowest level. Moist air will displace drier air below. Works well spring through fall. A more expensive but great fix is to locate one on the roof with a water supply and have ducts on the upper floor. In fall you can reverse air flow and suck cooler air to the roof. But an expensive install, usually. - Jim
     
  7. Jun 10, 2017 #6

    mfb

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    With a bit of engineering: attach a long hose to the fan, run it from upstairs to the lower floor, close the windows.
     
  8. Jun 10, 2017 #7

    JBA

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    As long as you have all other windows and doors shut except for the two with the fans then you should be drawing ambient outside air into the upstairs room, cooling it, delivering it to the bottom floor and a out through your lower window just as you expect.

    Possibly, the heat flow into the lower floor due to the higher outside air temperature and and sun radiant heat conducting through downstairs exterior walls and windows may be exceeding the rate at which your fans can circulate the cooled air to the bottom floor.
     
  9. Jun 10, 2017 #8
    So the room is so cool because of the evaporative cooler that I have in there (70), and while I was not expecting that it could cool the entire house down I was hoping for somewhere in the 75-78 range, but it is definitely better than the 99 outside. Thanks for the advice
     
  10. Jun 13, 2017 #9

    sophiecentaur

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    You need two paths between the two levels if you want effective circulation. As mentioned above, you will need at least one duct - the stair well can supply the other path. Cool air from an upstairs window is slightly more dense than the warm air downstairs. Given a bit of encouragement you can start a convection loop but you give things a chance to get started. You can get a bubble of cool air in the 'out' tube that will sit on top of the warm air beneath. An extractor fan at the bottom of the 'heat out' tube would probably be better than at the top because of the directed output flow. Once convection has started, it may even sustain itself as the walls of the exhaust tube warm up.
    Careful choice of where you put the exhaust outlet. Away from the prevailing wind.
     
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