Which way should the blades be turning to help me conserve heat? Should they be cutting up into the air, or down?
The one I grew up with was mounted 20 feet high and only turned in one direction, I’m not used to these here fancy bi-directional thingy-ma-bobers.
Hot air is less dense than cool air, so it pools at the top of your rooms. In the winter, the fan should blow the hot air down.
Some people reverse the fans in summer, but I’ve never found much advantage in that. A fan cannot evaporate the sweat off your skin if its blowing at the ceiling.
Ah! But how should it move the hot air down?
I disagree with Squink, noting that when the fan is reversed (pulling air up), it will force the air in the room to circulate without actually blowing across one’s skin, therefore, one eliminates cold spots or heat trapped at the ceiling without (as Squink notes), sending a cooling breeze across one’s skin.
I do have support for my position. (I will note that the article does provide some alternative views, closer to that of Squink, but that my general premise holds.)
I suspect that the actual, correct answer as to which direction is most efficient at redistributing ceiling heat depends on the size of the fan, size of the room, speed of the fan, and distance of the fan from ceiling.
As you know, ‘suction’ from a fan is not nearly as directional as the stream of air forced away by moving fan blades. That sets up the possibility that a fan blowing air at the ceiling will not take its input from all the air in the room, but merely from a layer of warm air up near the ceiling, and extending some inches below the whirling blades. Without the active mixing produced by a downward stream of warm air, you face the possibility of all your heat remaining locked in a spinning torus up above your head (ie air moves up through the fan, along the ceiling, down the walls, back to the fan, and up again- never reaching the floor).
As a practical matter, the correct directional setting for a room is the one which you find most comfortable.
The house isn’t small and has pretty high ceilings, 12 feet or so I think. I’ve got fans in 4 rooms, all suspended at about about 8 feet.
Right now they’re set the same as I had them in the summer, and even on the lowest setting I think the draft they create is more cooling than heating.
I’ll switch them all around and report back.
Try and contain your anticipation. Make some popcorn maybe.
Ok, for my particular house and fans, the best configuration appears to be with the leading edge of the fan blades tilted downward. No cooling breeze. If the winters in Atlanta lasted longer than 5 days, I’d perform a little experiment and compare my gas bills. Anyone in North Dakota have absolutely nothing to do?
Just asking, but do your fans not have a “reverse switch” on them?
The fan in the very room I’m typing this has a switch to turn the fan in one direction or another. So theoretically, it doesn’t matter which way the blades are turned, as the motion of the motor can force cool air up or down per the positon of the switch.
Not only that, but the fan (a Hunter, FWIW) has blades that can only be mounted one way (although the blades have an “oak finish” on one side and a “cherry finish” on the other, but this has nothing to do with the mouting angle).
IIRC, the illustration on the box of the bi-directional ceiling fans we purchased indicated we would obtain a significant cooling effect by running the blades clockwise in summer (leading edge of blade closer to the floor) while obtaining a marginal heating effect by running the blades counter-clockwise in winter (leading edge of blade closer to ceiling).
Empirically I can tell you that the clockwise perceived cooling effect feels very real and that the counter-clockwise effect is certainly less cooling than clockwise but I wouldn’t swear it actually creates a perceived heating effect. The boss usually turns the fans off in the winter.
YMMV
I do have reverse switches, and fixed blades. That’s why I was trying to describe which direction the leading edge of the blades were pointing.
Leading edge down is clockwise on my fan (looking up from the bottom), and the warmer of the two options, from what I can tell.
I’d have them off, but my ceilings are so high, I just know that all of my heat is hovering up there.
I have a fairly large room with 20 ft ceilings and a reversible fan mounted about 5 feet from the top. I’d be more than happy to perform this experiment, if I can find a stick long enough to throw the switch.
Len
We recently installed a new ceiling fan, and still have the manual around. The manufacturer recommends that for summertime operation, the fan blows down; for winter operation, the fan blows up.