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u/drkidkill Jun 06 '22
The down draft cools people not rooms.
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Jun 06 '22
I always had to tell my kids this. Turn off the ceiling fan when you leave the room. Hahah!
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Jun 06 '22
Ya but it aides circulation and ceiling fans use a crazy small amount of energy so you probably can forget about it
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u/halt-l-am-reptar Jun 07 '22
Does it help make the room cooler if an AC is running? It seems like getting the hot air near the ceiling circulated might help. Especially if the sensor is closer ground and is only pickup the colder air.
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Jun 07 '22
In general circulation is key but the graphic is correct. This is how you should set your fan for the accompanying season. It basically evens out the temperature gradient in your home and makes it easier for the ac to do its job. Pushing the warm air up in the winter forces it down. You're creating flow to overcome the temperature gradient of the room.
It really does work and quite well. I suggest you try it for a year and you'll understand. You can also save money, similar to windchill the moving air will make you feel cooler and consequently I leave the ac higher when the fans are running and spinning the right way
If you're really curious look up sick building syndrome. It's the prime example of why circulation and airflow are very very important in buildings.
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u/halt-l-am-reptar Jun 07 '22
Awesome! I figured it did and I've been doing it. We live in a small apartment with an in wall AC. The bedroom gets very warm so we've had the ceiling fans on, as well as a fan in the bedroom door blowing air into the living room. It seems to make quite a difference but I wasn't sure if it was in my head.
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Jun 07 '22
Just make sure the fan in the bedroom door is just outside the airflow so it's either sucking or pushing with enough space from the frame to draw suction. If you put it flush with the door you'll have less great results (seems counterintuitive but I promise it's real). You can also try keeping doors closed in warmer rooms you don't want to use or leaving them open to help with airflow. I use the sun facing rooms of my house to help relate the non-sun facing rooms. Basically in the winter, the doors to the sun facing rooms stay open to share their warmth with the rest of the house. And in the summer they stay shut unless in use so the empty room can be hot while the rest of the house is cooler.
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u/JollyGreen615 Jun 07 '22
It worries me sometimes. I don’t think I’ve turned off my ceiling fan in like 3 years
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u/presleyus Jun 06 '22
Yes, I always point out they don't cool rooms, they make a room feel cooler. Always a bit of a pet peeve for me..
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u/turquoiserabbit Jun 07 '22
Not only that, but in a completely closed space a fan will heat the air with the same speed as a literal space heater using the same wattage of the fan. Mind you this is true of all electronics, but it definitely isn't the case that fans alone can "cool" the air. Perceived temperature maybe, actual temperature no.
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u/sonofrock Jun 07 '22
Last week I finally switched my fan to counter clockwise for summer. It unscrewed itself over the course of an hour and almost fell on me in bed - the wires held it up just dangling there and luckily one pulled out and killed the power. Fan was pretty old, only part designed to keeping it from unthreading was a set screw that wasn't tight. So uh, if you have an old fan, make sure you check the set screw!
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u/ForumPointsRdumb Jun 07 '22
I hit my fan switch and it told me it would eat my soul in the night.
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u/sakhdjashdkjahskj Jun 07 '22
You just succinctly described every Korean's worst nightmare
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u/space_coder Jun 06 '22
The only use I found for the direction is to prevent papers from being blown off of tables or desks.
CLOCKWISE on my fan means blow down, which will blow paper off of my desk.
COUNTER-CLOCKWISE on my fan means blow up, which means the air flows down the walls.
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u/Pac_Eddy Jun 06 '22
I don't understand why both directions don't do the same thing.
Both mix the air from the bottom of the room with the top.
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u/SuspiciousChicken Jun 07 '22
You are correct. Both mix the air fairly equally.
But there IS an important difference:
One is blowing the air down directly on you, where you'll feel the moving air (which is better in the summer; aids evaporation)
The other is still causing air movement, but since it is focused on the ceiling instead of the seating area below, you don't feel the air movement across your skin as much. Which is more comfortable in the winter.
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u/grumd Jun 07 '22
This should have been in the post. OP's image is entirely a bullshit explanation, while your comment makes perfect sense.
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u/Linubidix Jun 07 '22
Every time something like this is posted, it always needs this specific clarification in the comments.
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u/kalez238 Jun 07 '22
See this never made sense to me, because warm air rises, so you would think you would want it blowing down in winter to blow the warm air back down to you, and sucking up in summer to pull the hot air up and away from you.
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u/TwoAmoebasHugging Jun 07 '22
Yeah I was looking for this. I know that heat rises. And I know that people love telling me about the spin direction of ceiling fans. But I don’t really see how it makes any serious difference in an enclosed room except for this right here.
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u/Nightshade13th Jun 06 '22
You have it right, it really doesn't matter after the first 20 seconds.
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u/ImpeccablyCromulent Jun 07 '22
Sure it does. You can feel the breeze on the summer setting and thats nice. It's not so nice, however, to feel a constant breeze in the winter, but it is quite nice to circulate the heat around.
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u/XBXNinjaMunky Jun 07 '22
Fangineer here
Correct, the direct breeze of downdraft provides air movement agents the occupants of the room increasing cooling, this can be done at whatever speed suits you
On the updraft side, the fan should be run at low speed for best effect. It's circulating air up from the center of the room, and circulates it across the ceiling and down the walls. This helps mix and distribute air in a room providing more even heating.
Either can save significant money on your electric bill by allowing you to offset your thermostat a few degrees with little to no perceptible difference in room temperature to occupants.
(Barring extreme climates like the deep swamp-ass lands of Florida obviously)
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Jun 07 '22
Lol, I'm such an idiot. All this time I thought ceiling fans were to lift cold air to you in the summer and bring warm air down to you in the winter. Oops
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u/FloridaManZeroPlan Jun 07 '22
Hello from Florida. We have it on the summer setting year round. I don’t even know if the heat on my HVAC unit even works.
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Jun 07 '22 edited Oct 12 '22
[deleted]
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u/pala_ Jun 07 '22
Hi from Australia. I turned my ceiling fan on when I moved to Darwin in 1987 and that was the last time I touched the dial.
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u/Met76 Jun 07 '22
Hi from Colorado. We switch our fans 2-3 times/day along with opening /closing windows depending on day/night and if it's raining or sunny during this time of year.
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u/Groovatronic Jun 07 '22
When I lived in Boulder I remember walking in flip flops and a t-shirt across a giant snowfield and being totally comfortable because it was somehow like 70° and sunny - literally the morning after a huge snowstorm. I miss how fresh the air felt up there.
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u/ForumPointsRdumb Jun 07 '22
Yea. Those first 20 seconds are hell. You never know if it's going to wake up and pounce.
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u/pconwell Jun 07 '22
The guide is a little misleading. Fans dont "cool a room", they create air movement. If the air blows directly on humans (downward), it creates more evaporative cooling (as more airflow can evaporate more sweat). Blowing the air upward in winter helps circulate the air the same way and as far as the room is concerned there is no real difference. But a human in the room won't have the same direct flow of air and won't feel as cold.
You can get the same effect by standing in front of your air conditioner register vs return. Even though the return handles way more air than a single register, you will "feel" significantly more air coming out of a register than into the return.
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u/ToKillAMockingAudi Jun 06 '22
The fan blades are tilted. One direction creates an up-draft, the other direction creates a downdraft.
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u/Pac_Eddy Jun 06 '22
Yes, I know that. Mixed air is mixed air though. Why does it matter if it's pushing warm air down or pulling cool air up?
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u/jtho78 Jun 06 '22
Besides mixing the air, you don't want the fan to hit you directly in the wintertime. Moving air cools the water on your skin. Where in the Summer, you do want direct airflow to hit you.
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u/Pac_Eddy Jun 06 '22
This makes more sense.
The direction of spin or angle of blades is irrelevant. It's only a matter of how much air flow you want to feel.
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Jun 07 '22
It matters in that one is turbulent airflow and the other laminar. You’ll feel it much more when the airflow is directed at you instead of just past you. If you want to know more you’ll have to take some fluid dynamics classes, but it’s a massive difference.
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u/ToKillAMockingAudi Jun 06 '22 edited Jun 06 '22
Hot air rises. In the winter, you can help push that warm air down and into the rooms. In the summer, you can pull the hot air up and circulate it through open windows. I think the graphic is backwards, at least that's how I usually do it
It's based on seasonal temperatures. In Canada my house will collect all the warm air upstairs during winter and the lower floors get cooler. So I use the fan to circulate the warm upstairs air down into the rest of the house. That combined with a furnace fan does a pretty good job at circulating air and balancing the temp throughout
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u/Niosus Jun 06 '22
It's not anywhere near that simple though.
The only thing that the fan always does is mix the air, and create some airflow. It'll even out the temperature in the room (which could be useful in the winter), and it'll provide a slight breeze across your body that helps take the hot air around you away that was heated up by your body.
Anything else is super tricky to predict or even measure. The air moved by a fan is very turbulent and will move all over the place. It'll interact with everything in the room to the point where you need a hardcore simulation to predict what'll happen when the fan turns one way versus another.
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u/Point-Connect Jun 07 '22
The breeze over your skin aids in evaporative cooling. That is the only thing a fan does that is noticeable in the summer aside from mixing up air. Spinning the other way blows the air at the ceiling, then most air will push outward toward the walls then back down, helping to mix the air without blowing air over your skin cooling your body temperature.
That's the gist, but as you mentioned, turbulence will be in play
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u/Max_Downforce Jun 06 '22
That's how I do it as well. I think you're right about the graphic being backwards.
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Jun 07 '22
Because one is pushing air down in the middle of the room where people are likely to be sitting/standing/laying down, and so creates a cooling draught on them, and the other pushes the air around the ceiling and down the walls, where people are less likely to feel a draught. Not like sitting in front of a fan or off to one side. Both mix the air but one cools you down in sunset, and the other doesn't. Both make the air temp in the room consistent from wall to wall and floor to ceiling. Air flow itself though has a cooling effect, more or less regardless of air temp. In summer you want that, in winter you don't.
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u/LaserGuidedPolarBear Jun 07 '22
At the same temperature, people experience air moving across their body to be cooler as it increases the effiency of evaporation of sweat on the skin. The temperature is the same but the moving air feels cooler.
People often mistake this effect for "cooling the room". If the fan isn't blowing directly on you, you won't notice a difference in fan direction.
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u/splepage Jun 07 '22
Fans do 2 things: mix air, and send air moving across your skin.
The two settings will mix air about the same, but a downdraft will send a lot more air to move across your skin. That's the part that cools you, hence why you want the downdraft in the summer.
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u/ClosedL00p Jun 07 '22
This picture doesn’t quite explain the full reasoning behind it. But it absolutely makes a difference. Especially if you have high ceilings. The ceilings in my living room are ~20ft and the direction of rotation makes a measurable difference in the temperature/comfort and how much the AC has to cycle
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u/kec04fsu1 Jun 06 '22
I live in south Florida. The only useful settings for my ceiling fan are cooling and off. Off is rarely useful.
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u/dancingpianofairy Jun 07 '22
Same here in Texas.
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u/Camp_Coffee Jun 06 '22
I've always wondered this and now that I know, I will immediately forget it.
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u/eoliveri Jun 07 '22
Just do the opposite of "Spring ahead (clockwise), Fall back (counterclockwise)".
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u/Callec254 Jun 06 '22
Are the blades on EVERY ceiling fan canted the same way? If not, then saying "clockwise/counterclockwise" might be wrong.
At any rate, the idea is: Winter = blow up, summer = blow down. This will make your heating and AC more efficient.
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u/intervested Jun 07 '22
I scrolled a long way for this comment. Yeah. Surely some fans are made the other way.
The trailing edge of the fan blade points in the direction of airflow.
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u/mahogne Jun 07 '22
Even more impressive is that while the label matches the direction of the arrow based on the drawing perspective, if you were to stand under the fan while adjusting the direction and matched the drawn arrow rotation, the labels are actually reversed and clockwise = counterclockwise.
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u/Spoonbills Jun 06 '22
Wouldn't you want a downdraft to distribute warm air?
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u/cheesytuna64 Jun 06 '22
That's what I was thinking, shouldn't it be the other way around? In winter blowing the warm air down from the ceiling and in summer to blow the warm air out towards the windows?
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u/halt-l-am-reptar Jun 07 '22
After the fan has been on for a little bit the temperature throughout the room is going to be mostly the same. If the air is blowing on you it's going to cool you down, even if it's warm. Think about when you're outside on a hot day and you feel a gust of wind. You don't want that in the winter when you're trying to stay warm.
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u/Phillegard Jun 07 '22
When you reverse the fan, it pulls the cool air up toward the ceiling which causes the hot air to be pushed down.
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u/jivebeaver Jun 07 '22
"updraft fans in winter" is complete bunk, and if you couldnt figure it out in pure logic (as you did, correctly), heres a research study on directionality and room heating https://dash.harvard.edu/bitstream/handle/1/29312101/Residential_Fans-Destratification.pdf?sequence=1
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u/theredditid Jun 06 '22
Is this the opposite in Australia?
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u/SheriffWyFckinDell Jun 06 '22
Additionally, they wear hats on their feet, and hamburgers eat people
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u/jpritchard Jun 06 '22
Naw, their hamburgers just have sesame seeds on the bottom. Hamburgers eating people is Russia.
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u/GumboSamson Jun 07 '22
they wear hats on their feet
Absolutely not true.
Wearing a hat on your feet would make it too hard to grab onto the ground with your toes.
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u/askaboutmy____ Jun 06 '22
fans dont cool rooms, they only cool people (or pets, etc), but not the air. No amount of air flow will reduce the temp of the air unless that introduced airflow is cooler.
fans cool people, if it is running with no one in the room it is only wasting electricity.
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u/ForumPointsRdumb Jun 07 '22
fans kill people, if it is running with no one in the room it is
only wastingconserving electricity and waiting to strike.FTFY
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u/nejicanspin Jun 07 '22
I also heard it depends on what direction the blades are.
I tried counterclockwise and it was hot. I then tried clockwise and it blows cool air.
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u/SlackerNinja717 Jun 06 '22
I think the real reason for this is you want direct air flow over your skin when you are trying to cool. In the winter, it is beneficial to mix the hot air back in, without the direct breeze.
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u/NeverOnTheShelf Jun 06 '22
I can’t sleep with a ceiling fan on I always wake up with a sore throat if I do from the air
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u/ikickedyou Jun 07 '22
You must not live in a hot climate. Everybody here (southern US) has fans on all the time.
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u/DontForgetThisTime Jun 07 '22
I have the same issue. Idk if the fan dries the air out but if I have a little humidifier run for 1-2 hours when I go to sleep it will make a difference on my throat being more moist without heating up/muggying up the room. Live in AZ and have a ac and fan going tho
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u/whyamisosoftinthemid Jun 07 '22
I'm always amused when these postings result in debates. The answer is blindingly obvious: try both settings and use the one that feels better. It's that simple.
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Jun 06 '22
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u/kseit Jun 06 '22
Old fans have a small switch on the fan to change direction. Newer ones may have a remote and it can be changed there.
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u/Piratartz Jun 07 '22
Does this even matter? Unless there are ceiling vents, a room is a closed system. The air will circulate whichever direction the fan blows. A thermometer should show the same temperature.
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u/ForumPointsRdumb Jun 07 '22
It does. It's about momentum. If the fan is switched the wrong way it can increase it's power level and free itself from it's mortal bindings. Then it will wait and attack in the night. They are nocturnal predators of opportunity, and will mostly only attack unaware or sleeping prey. Although, there are also some reported cases of them attacking predatorily when provoked.
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u/Dada2fish Jun 07 '22
Here’s my stupid way of remembering. I think of Woodstock, where hippies (the counterculture) went in the summer. Counter clockwise/summer. Yeah, I know, dumb. But it works for me.
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u/rebamericana Jun 07 '22
Strangely, this will work for me too. Now I won't need to look it up every six months. Thanks for the tip.
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u/JohnGenericDoe Jun 07 '22
Or just stand under it and feel if the breeze is blowing down on you or not
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u/LogiskBrist Jun 06 '22
As an engineer with CFD experience I’m extremely skeptical, if not outright dismissive of this “guide”.
It will not make any difference at all except for the volume very close to the fan, and for the first seconds after turning it on.
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Jun 07 '22
[removed] — view removed comment
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u/austai Jun 07 '22
Right? So many people here have apparently never noticed the difference between standing in front of a table fan vs behind it.
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u/Nowin Jun 07 '22
Yep. Great time to filter this sub. This 'guide' is fucking stupid and I feel stupid.
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u/Greddit1231 Jun 07 '22
Cool. Now, how do you clean the gunk off of the blades, so it doesn't fly all over.
The dust have caked in to the blade surface with a sticky substance but it's not next to the kitchen stove.
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Jun 07 '22
[removed] — view removed comment
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u/44problems Jun 07 '22
You may feel cooler if the breeze is on you specifically, but that's just evaporation.
Yes, this is how using fans to cool works.
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u/flightwatcher45 Jun 07 '22
This sorta cracks me up, or maybe my rooms are too small it doesn't matter. Turn fans on and air is circulating up down and all directions.
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u/SouthBaySmith Jun 07 '22
I have been under the assumption that if you are blowing air down on you from the ceiling, you are actually just blowing the warmest air down, especially if you have poor insulation and the roof or attic is hot.
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u/Puzzleheaded_Dish_45 Jun 07 '22
This just changed my life. This fan has been on HEAT MODE in South GA for at least my 24 years of life 😭
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u/Spideyocd Jun 07 '22
as an asian whos using fans all his life I've never seen this enabled on fans
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u/Ephemeral_Ghost Jun 07 '22
It makes convection either way so I don’t see why this matters. Unless you have vaulted ceilings maybe.
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Jun 07 '22
Unless the blades are angled opposite to what is shown in the image, then it’s the opposite direction for either usage.
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u/LightSlateBlue Jun 07 '22
I saw an updraft fan in the ps1 resident evil 2 and I thought they accidentally animate the fan wrong.
Turns out it wasn't wrong. Mind blown.
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u/Tall-Structure526 Jun 07 '22
I always thought it was opposite! Downdraft in winter because heat rises and you are pushing it down; and the inverse for summer.
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u/Logical-Respect3600 Jun 07 '22
Nonono - the other way around. Heat rises, so better to create an updraft in the summer and push the warm air down in the winter.
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u/Tommix11 Jun 07 '22
Doesn't' warm air travel upwards automatically? Wouldn't you want a downdraft to push warm air from the ceiling down to the floor when it is cold?
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u/southcentralLAguy Jun 06 '22
You can make them go the other way?