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Old 08-27-2016, 09:17 PM
chacoguy chacoguy is offline
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My ceiling fan has a switch where it can go up or down.

How can that possibly matter?

The blades are about four inches wide and the whole rig is only about eight inches from the ceiling.

Last edited by chacoguy; 08-27-2016 at 09:18 PM.
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  #2  
Old 08-27-2016, 09:25 PM
SantaMan SantaMan is offline
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Do you mean the switch that determines the direction of air flow?
In winter, I want the rising warm air to come back down.
In summer, I want to encourage the warm air to exit at the top.
  #3  
Old 08-27-2016, 09:25 PM
wolfman wolfman is offline
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You mean a switch that changes the rotation from sucking up to pushing down?
  #4  
Old 08-27-2016, 09:26 PM
Joey P Joey P is offline
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In theory, it should blow down in summer so the air blowing on you makes you feel cooler. In winter, reverse it so it blows up at the ceiling, you won't feel the breeze nearly as much, but it'll still circulate the air (and help move the warm air off the ceiling).

I've also heard the opposite of this, having it blowing down in winter to get the hot air off the ceiling and up in summer to get the cool air off the floor. In the end, it just circulates all the air, it's not like it's going to sort it out and keep the cool and hot air where you want it based on the direction it's spinning.

Most people just have it always blowing down and never think about. Personally, I'm not a big fan of having having a fan on me all the time (it dries out my eyes, even when I sleep) so I usually have them set up blow towards the ceiling. If I do want to feel an actual breeze, I just turn it up higher, but if I just want the air moving, the first or second speed is perfect.

Last edited by Joey P; 08-27-2016 at 09:28 PM.
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Old 08-27-2016, 09:31 PM
engineer_comp_geek engineer_comp_geek is offline
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People typically set these so that in the summer, the air blows straight down from the fan. The moving air helps people feel cooler.

In the winter, turning on the ceiling fan helps to circulate the air so that you don't end up with all of the warm air at the ceiling and cold air on your feet. But moving air in the winter doesn't feel comfortable, so flip the switch so that the fan sucks the air up from the middle of the room (the sucking is less directional and so the moving air isn't as noticeable). The air then goes across the ceiling and drops closer to the walls.

Or you can do what a lot of people do and just ignore the switch and leave it so that it always blows downward.

ETA: or what Joey P said (that post wasn't there when I started typing).

Last edited by engineer_comp_geek; 08-27-2016 at 09:32 PM.
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Old 08-27-2016, 09:40 PM
Joey P Joey P is offline
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Just something to add. As someone that keeps his fans (more or less) always directed upwards. Doing that, if you use them a lot, will result in dusty ceilings. Not horrible, but bad enough that every few years you'll look up and say 'hm, I don't think I've ever had to clean a ceiling before. I'm not sure how to go about that'.
  #7  
Old 08-27-2016, 09:41 PM
SantaMan SantaMan is offline
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Ignorance Fought. You folks were right and I was wrong:Link
"In the summer, use the ceiling fan in the counterclockwise direction. While standing directly under the ceiling fan you should feel a cool breeze. The airflow produced creates a wind-chill effect, making you "feel" cooler. In the winter, reverse the motor and operate the ceiling fan at low speed in the clockwise direction. This produces a gentle updraft, which forces warm air near the ceiling down into the occupied space. Remember to adjust your thermostat when using your ceiling fan — additional energy and dollar savings could be realized with this simple step!"

Last edited by SantaMan; 08-27-2016 at 09:41 PM.
  #8  
Old 08-27-2016, 10:00 PM
Joey P Joey P is offline
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Quote:
Originally Posted by SantaMan View Post
Remember to adjust your thermostat when using your ceiling fan additional energy and dollar savings could be realized with this simple step!"
That's exactly what I do. There's plenty of times when I'm warm and I'll look at the t-stat and see that the AC is turned down low enough and just flipping on the ceiling fan* is all I need to make it 'feel' a few degrees cooler.

*If I'm in bed or just laying in the couch or something, this is usually in conjunction with letting one of my legs hang out from under my blanket. Moving air over exposed skin will cool you off really fast.
  #9  
Old 08-28-2016, 06:46 AM
bob++ bob++ is offline
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In houses like mine, with radiators rather than blown air central heating, having the fan such the air up, helps to distribute the warmth around the room.
  #10  
Old 08-28-2016, 10:45 AM
jjakucyk jjakucyk is offline
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Having the fan blow up creates a sort of laminar airflow across the ceiling and walls that can actually harm comfort in both the winter and summer if you live in a poorly insulated building, especially one built of solid masonry. In the winter the walls are already cold so you're adding more airflow and creating drafts along the wall where you least want them. In the summer you lose the cool breeze effect and also create a kind of hot envelope around the room. If the headboard of your bed or a couch is against an outside wall you'll notice it more. I've found that just leaving the fans blowing down works best in such a situation, but keep them on low speed in the winter which keeps the air circulated without being drafty, and bump them up to medium or high in the summer when you need the breeze.
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Old 08-28-2016, 12:25 PM
Channing Idaho Banks Channing Idaho Banks is offline
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I've always wondered if it's bad for the motor to flick the switch while the fan is turning. My guess is yes however when I do it I use my hand to stop the fan and then give it a push the other direction.
  #12  
Old 08-28-2016, 01:31 PM
I. Dunno I. Dunno is offline
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I would at least turn the fan to the OFF position before switching even if you don't want to wait for it to stop. And perhaps that's what you do since you are sticking your hand in there.

I think if it's turning and you switch direction, the motor has to work a little harder and will draw a bit more current to get things going the other way. I suppose over time it could shorten its life but those motors seem to last a good long time anyway.
  #13  
Old 08-28-2016, 02:18 PM
JackieLikesVariety JackieLikesVariety is online now
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Quote:
Originally Posted by chacoguy View Post
How can that possibly matter?

The blades are about four inches wide and the whole rig is only about eight inches from the ceiling.

I never use my switch because if I have the fan on I want it to blow down on me and if I don't want that I turn it off.

YM as always MV

Last edited by JackieLikesVariety; 08-28-2016 at 02:20 PM.
  #14  
Old 08-28-2016, 07:40 PM
Melbourne Melbourne is online now
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Quote:
Originally Posted by SantaMan View Post
Quote:
Originally Posted by the internet
The airflow produced creates a wind-chill effect, making you "feel" cooler.

Damn. Windchill only makes me *feel* cooler? I should have left my thermals behind last time I went skiing.
  #15  
Old 08-29-2016, 10:15 AM
MrSquishy MrSquishy is offline
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Quote:
Originally Posted by Melbourne View Post
Damn. Windchill only makes me *feel* cooler? I should have left my thermals behind last time I went skiing.
Not totally sure where you're going with this, but yes, wind chill only makes heat-producing objects (like humans) feel cooler, because the wind immediately blows away the heat you produce. A thermometer (measuring the actual temperature) does not change when the wind picks up.

Uh, well unless the wind is blowing in a cold front or something. But you know what I meant.
  #16  
Old 08-29-2016, 12:32 PM
engineer_comp_geek engineer_comp_geek is offline
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Quote:
Originally Posted by Channing Idaho Banks View Post
I've always wondered if it's bad for the motor to flick the switch while the fan is turning. My guess is yes however when I do it I use my hand to stop the fan and then give it a push the other direction.
It's a bit harsh on the motor windings. Most fans have reasonably rugged motors and won't be damaged by this sort of thing though.
  #17  
Old 08-29-2016, 12:40 PM
Atamasama Atamasama is online now
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Don't think that wind chill is a psychological effect or anything. It's a real physical effect. With the wind blowing away your heat envelope, you'll get colder faster because still (warm or cool) air acts as an insulator. When you lose that, you will lose heat much faster and your body will be chilled more quickly, even if the thermometer isn't registering a difference.

It works the other way too, making cool things get warm faster. As I learned as a kid when I stuck my hand out the car window holding an ice cream cone. It began melting instantly and the ice cream was just pouring down my hand like a faucet.
  #18  
Old 08-29-2016, 04:16 PM
MrSquishy MrSquishy is offline
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Quote:
Originally Posted by Atamasama View Post
Don't think that wind chill is a psychological effect or anything. It's a real physical effect. With the wind blowing away your heat envelope, you'll get colder faster because still (warm or cool) air acts as an insulator. When you lose that, you will lose heat much faster and your body will be chilled more quickly, even if the thermometer isn't registering a difference.
Ah, good point, I hadn't thought about it that way. I didn't mean to make it sound like it's only psychological, just that it isn't a "real" temperature change.

It only affects things that produce (or have residual) heat. That is, if you leave an object outdoors when the temperature is -30 degrees, that object will gradually get colder and colder until it is -30 degrees on the surface. Then, if a wind picks up and makes the apparent temperature -40 degrees "with the wind chill", that object remains -30 degrees.

My wife always wants me to plug in the car in the winter when it's going to be -20 or -25 "with the wind chill". I argue that the "real" temperature is only going to be -10 and she doesn't tell me to plug in the car when it's -10. I feel smug knowing am I right (as I plug in the car).
  #19  
Old 08-29-2016, 04:35 PM
kanicbird kanicbird is offline
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I've used them in pairs to circulate air between 2 rooms in a semi-open floor plan, one upward the other downward causes a breeze in the hallway while the return air is higher up over a wall that does not come all the way to the ceiling.
  #20  
Old 08-29-2016, 10:51 PM
rbroome rbroome is offline
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Quote:
Originally Posted by chacoguy View Post
How can that possibly matter?

The blades are about four inches wide and the whole rig is only about eight inches from the ceiling.
One issue you will have is that your fan is almost certainly mounted too close to the ceiling. They are designed for a certain distance from the ceiling and being too close or too far reduces their effectiveness. Not that anyone pays any attention to this detail, but that is how fans are designed.
  #21  
Old 08-30-2016, 03:29 AM
TokyoBayer TokyoBayer is offline
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Something else to keep in mind is that ceiling fans can mix up the air in a room. One poster in another thread here on the Dope related how his electric bill increased when he used his ceiling fan because it brought the hot air down from the ceiling and required more cooling. I can't verify how much of an actual effect that would have on most rooms.

We used "free standing" fans which blow air sideways, and it helps us keep the thermostat up higher.

Quote:
Originally Posted by MrSquishy View Post
Ah, good point, I hadn't thought about it that way. I didn't mean to make it sound like it's only psychological, just that it isn't a "real" temperature change.

It only affects things that produce (or have residual) heat. That is, if you leave an object outdoors when the temperature is -30 degrees, that object will gradually get colder and colder until it is -30 degrees on the surface. Then, if a wind picks up and makes the apparent temperature -40 degrees "with the wind chill", that object remains -30 degrees.
My bolding.

As since we are discussing the art of making people in a room feel comfortable and not absolute temperature of the coffee table, this seems to be overly pedantic.

I grew up an an extremely dry environment in Utah and now live in a humid semi tropical climate. Humidity and air flow make large differences in how we, people, feel at any given temperature. Both of are directly related to our actual, measurable comfort.

I haven't asked the coffee table what it thinks, but since it lacks self generation of heat, doesn't have exposed skin and there are no sweat glands, I think it doesn't care.
  #22  
Old 08-30-2016, 04:51 AM
jjakucyk jjakucyk is offline
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Quote:
Originally Posted by rbroome View Post
One issue you will have is that your fan is almost certainly mounted too close to the ceiling. They are designed for a certain distance from the ceiling and being too close or too far reduces their effectiveness. Not that anyone pays any attention to this detail, but that is how fans are designed.
It's hard to blame someone for having a fan too close to the ceiling when the fan manufacturers design them with motor assemblies that mount directly to the ceiling.
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