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Autonow
Average Member
  
USA
106 Posts |
Posted - 07/27/2013 : 07:37:07 AM
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Has anyone done a study on "best approach" to using ceiling fans to control temperature?
You have your HVAC system. Can ceiling fans improve efficiency?
In a heating mode should fans pull air up or push down. same thing for the cooling mode. Just curious what people are doing.
All fans on or use the fans to push air around the house |
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Tfitzpatri8
Administrator
    
USA
10882 Posts |
Posted - 07/27/2013 : 4:47:47 PM
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Heat rises. When the heat is on, a fan should pull air from below to mix cooler air near the floor with warmer air near the ceiling and force the mixed air back down the walls to the floor. When the AC is on, pushing air toward occupants promotes evaporation and a cooling sensation. |
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stusviews
Advanced Member
    
USA
15854 Posts |
Posted - 07/27/2013 : 4:54:06 PM
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Down to cool, up to heat. |
Stu's Views is Education and Fun. What do YOU want to VIEW today? MathLandia High school mathematics learning fun. Both Stu's Views and MathLandia are free websites that do not sell anything. Saving energy is not always free. Be a world saver.
Please don't PM with questions that can be asked in a forum. |
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Chandra @ DelMar
Starting Member
1 Posts |
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Autonow
Average Member
  
USA
106 Posts |
Posted - 10/31/2013 : 1:10:08 PM
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I always love discussions of this type!  One fact of nature... Heat rises cool air falls, We seem to agree. So if all your heat is rising (collecting at the ceiling) You would think you would want to Push the hot air back down.. (opposite on the consensus here)
Lets look at it from a different approach, Is the goal to mix the air for it to be uniform in temp? If this is the case then you need to look at the efficiency of the fan. can it move more air pushing down or pulling up? Generally considering all the aerodynamics I would say it moves more air pushing down. I say this based on the exit effect of the ceiling when pulling up and the entrainment effect when pushing down.
So If you are staying warm and pushing the air down (humor me) you are pushing a lighter mass air against a more dense air (cold) so you would think it would not move very well up the wall.. BUT you are adding energy / momentum from the fan to give it added velocity so it may do well in stiring the mass to a more uniform temp. At least the immediate effect is to push the warmer air to you! . And at the least it will be pushing the air horizontally and perhaps out the window cracks and door jams from which it came in in the first place.
Ok now consider pulling air up. Now you are trying to suck the cold air up (that wants to stay at the floor) to the fan to mix with the warm air at the ceiling. Warm air still rises so why doesn't it stay at the ceiling? And since you are sucking from the floor why aren't you sucking in more cold air in from the windows and door jams.
Did I convince anyone that snow falls up Charlie Brown. It comes out of the ground a swirls around so It only looks like it is falling!
just saying! Have fun..
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Vikran6721
Starting Member
India
1 Posts |
Posted - 06/25/2019 : 01:32:44 AM
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the best way to keep the room feeling cool is to open the window and put a Ceiling fan or pedestal fan in it facing the interior. The cooler air from outside would be blowing onto sweaty bodies, helping them evaporate sweat even faster. |
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JohiahKep
Starting Member
India
4 Posts |
Posted - 11/09/2019 : 09:16:38 AM
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Open windows and place a ceiling fan interior and you will feel it cooll
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VDB5590
Starting Member
Belgium
4 Posts |
Posted - 01/29/2020 : 09:11:49 AM
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And what to do when it's hot inside and hotter outside? When the heat really goes off the rails, a fan just ends up blowing hot air on you, unless it's a super powerful pedestal fan, then it's difficult to tolerate. |
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Willied21
Starting Member
USA
2 Posts |
Posted - 04/05/2020 : 8:48:05 PM
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quality way to preserve the room feeling cool is to open the window and put a Ceiling fan or pedestal fan in it dealing with the interior. The cooler air from outdoor would be blowing onto sweaty bodies, assisting them evaporate sweat even quicker
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