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View Full Version : Should my ceiling fan blow or suck?


ShermanAter
11-26-2008, 10:49 PM
I can never remember which way my ceiling fan should run in the winter months to circulate heat and "save" energy.

In the summer I have it run clockwise, or in the downward position as it helps circulate the air and acts as a regular fan.

My question is, if I keep it running that way will it not suck the "hot" air from the ceiling and bring it down?
Or should I have it run counter clockwise, blowing the "hot" air up to bounce off the ceiling and back down.

Does it make a difference either way?

Happy Thanksgiving ,

Sherm

beowulff
11-26-2008, 10:53 PM
Supposedly, you want it to blow downward in the summer (so you feel a breeze), and upwards in the winter. We just turn ours off in the winter...

Philster
11-26-2008, 10:54 PM
Ugh...I loathe this subject.

Spinning it so that it blows down creates a wind chill effect -- not desirable in winter.

Spinning it so that it forces air up could push hot air towards the ceiling and down walls, and could push some of the houses warmer air down....the theory being that some warmer air comes down and doesn't blow directly on you. Warm is relative, because it won't feel warm, it is just warmer than the air below it.

If it makes you feel the air moving, then it probably is best to leave the darn thing off.

outlierrn
11-26-2008, 11:11 PM
I though it was spin down in winter to push warm air down, and up in summer to pull cool air up. Hot air at the ceiling doesn't do you much good, likewise cool air at your feet.

ZenBeam
11-27-2008, 09:31 AM
I've found that having the fan blow up still lets me feel the air movement, it's just not as breezy as when it is blowing down. In the summer, choose the direction based on how much you want to feel the air movement. Either direction will circulate the air. If you want it on in to mix the warmer air from the ceiling in winter, have it blow up.

Santo Rugger
11-27-2008, 11:03 AM
I though it was spin down in winter to push warm air down, and up in summer to pull cool air up. Hot air at the ceiling doesn't do you much good, likewise cool air at your feet.I think it's the opposite. If you imagine a cylinder below the fan, it will have a certain cross sectional area. The rest of the room will have another, much larger area. So, if we have the air come up in that cylinder during the winter, that will force the warmer air down along the walls (where people are more likely to be sitting, and also warming up the walls). Vice versa in the summer.

Philster
11-27-2008, 11:40 AM
In winter, it invariably leads to drafts, and that is usually uncomfortable.

Man With a Cat
11-27-2008, 11:49 AM
Up in winter, down in summer. To remember this, I remember that in the northern hemisphere it warmer in the south (down on a map), so warm weather equals down.

My foyer fan is 18 feet off the ground, so I adapted a broomstick, with a notch in the end that will grab the switch on the fan base, and from the railing I can lean a little, catch the switch and change the direction.

Pain in the ass.

Qadgop the Mercotan
11-27-2008, 11:58 AM
I recall reading an article that said it really doesn't make any damn difference which way you set it to spin, no matter what season. The effects described above are miniscule and not even measurable for the most part. At least on the scale of most people's houses.

Chimera
11-27-2008, 12:18 PM
Downspin: You're pushing the air mass surrounding the fan downward.
a> You feel the draft of air in the center of the room.
b> You're drawing up air along the outside walls.

So you're pulling up the colder floor level air along the outside walls where it blends with the warmer ceiling air and is sent down in the center of the room.

If this is a room with poorly insulated outside walls on a very hot or very cold day;
a> In summer, you're drawing up that cooler air over a warm surface, cooling the outside wall and warming the inside air before it recirculates.
b> In winter, you're drawing that air up along a colder surface, warming the outside wall and cooling the inside air before it recirculates.

Of course;

Upspin; You're pushing air upward into the ceiling and forcing it outward.
a> you get less of a draft because the real draft is along the outside walls. You may feel it on the couch against that wall, however.
b> You're pushing air downward along the outside walls.

So again, if the house is very poorly insulated and it's a very hot or very cold day, you're really just cooling or heating the outside wall more efficiently and messing with your interior AC or Heating. This is probably a bit counter-productive.

In a more well insulated house, this is perhaps less of an issue, and it becomes more of an issue of comfort. Does the draft in the middle of the room help you or bother you? When you're sitting on the couch against the wall, does that air sliding down the back of your neck bug the shit out of you?


I had exactly ONE ceiling fan in my old (1941) house, in the center room - the dining room. I would blow it downward in summer because the breeze felt good (I didn't have central air and had really really crappy old window units that couldn't keep up). I blew it upward in winter to draw the cold air off the floor and just to generally circulate air in a house that didn't fare so well in that department.

ZenBeam
11-27-2008, 02:07 PM
I recall reading an article that said it really doesn't make any damn difference which way you set it to spin, no matter what season. The effects described above are miniscule and not even measurable for the most part. At least on the scale of most people's houses.From personal experience, the bolded part is certainly not true.

engineer_comp_geek
11-27-2008, 02:28 PM
In the summer, the moving air feels cooler than it is (it's the same idea behind wind chill factor) which makes people feel more comfortable on hot days.

In the winter, if the air doesn't circulate then the warm air rises and the cold air tends to settle, which means people's feet get cold. You want the air to circulate in the winter but you don't want people to feel the sensation of moving air, since this will make them uncomfortable (it's that wind chill thing again).

You might think that it doesn't make any difference, because the same amount of air is moving either way, but it does make a difference, and you can demonstrate why very easily. When the fan is pushing down, the air is very directional and therefore much more noticeable. When the fan is pulling up, it is sucking air in from all directions. This is the same as when you blow out a candle. It is very easy to blow out a candle, but much more difficult to extinguish a candle by sucking the air in, even though the same amount of air is moving in either case.

In the winter, people tend to set their fan on the lowest setting. They want the air to circulate but you don't need it to be blowing at high speed or anything. Depending on how low the low speed is on the fan, the amount of air moving may be small enough that the air movement isn't noticeable either way, which gives some validity to QtM's point. It's definitely not true in all fans in all homes though.

Leaffan
11-27-2008, 04:15 PM
Advice I heard from a home renovation specialist, on a syndicated radio show here, stated that he never reverses fans to suck up. As mentioned not only are the results are insignificant, BUT over time you end up covering your stippled ceiling in dust and it is almost impossible to clean.

ShermanAter
11-27-2008, 08:27 PM
Thanks for the responses everybody.

While I tend to agree with Quadgop, engineer_comp_geek makes some interesting points.

FWIW I have mine in the up position(to avoid the breeze) at the lowest setting (to avoid the dusty ceiling)

Harmonious Discord
11-27-2008, 08:50 PM
The air circulates in a torus and it doesn't matter which way it goes under the fan. I agree with blow air down under the fan, because the ceiling will get dirty with the air blowing up.

sailor
11-28-2008, 05:41 AM
I recall reading an article that said it really doesn't make any damn difference which way you set it to spin, no matter what season. The effects described above are miniscule and not even measurable for the most part. At least on the scale of most people's houses. I suppose it depends on the room, the fan, the person, the humidity, the temperature and the price of isotopes in Deli but in my case the difference is very noticeable. You can put me in the category that feels a fan blowing down in winter makes me feel colder and I would rather have it off.

BarnOwl
11-28-2008, 07:23 AM
We have electrically heated ceilings in the den and dining room, thanks to the previous owner.

So, should my overhead fan in the den blow in winter?

ZenBeam
11-28-2008, 11:44 AM
Up.

Or you could try it both ways, and see what works best for you.

Stoid
11-28-2008, 01:45 PM
Sorry...

BarnOwl
11-28-2008, 02:11 PM
Up.

Or you could try it both ways, and see what works best for you.

Okay, I'll try it both ways - much later, however.

hende
11-28-2008, 02:28 PM
I was always told "Heat-Up" and "Cool-Down". It's pretty easy to remember although I'm not sure it really affects the temp either way.

sqweels
11-28-2008, 02:53 PM
Paradoxically, mine does both and neither at the same time.

























IOW, it doesn't work. :D

Really Not All That Bright
11-28-2008, 02:58 PM
I go with down in summer and "off" in winter.

Rigamarole
11-28-2008, 03:03 PM
Just count yourself lucky you have an appliance willing to do it at all, rather than get caught up in the terminology.

Bosda Di'Chi of Tricor
11-28-2008, 03:15 PM
Thread title seems vaguely obscene....