YSK: Running your fan when you are not in the room actually warms the room. Fans don’t actually cool anything, instead they help the human body more efficiently cool itself. It also helps churn the air in the room, which might make it feel fresher depending on the situation. But it only works directly on humans, because we use evaporation to lose heat. Fans however do use a lot of power and most of that power gets turned into heat, warming the room. So when there’s nobody in the room, turn off the fan.
This obviously doesn’t apply to fans that draw or push air somewhere else. A fan in a window, with another window open opposite can be useful without anybody around. Pro tip: If you want to cool the room you’re going to be (the bedroom for example) using outside air, don’t put the fan in the window in that room. It’s much more effective to put a fan in another room blowing outside and having the window in the room you want to cool the only other open window. It draws in cool air much faster, cooling down the room. Also don’t put the fan directly in the window, fans create a column of air that gets wider with distance. If you put the fan in the window, the column doing the work is about as large as the fan, which is presumably smaller than the window. By putting the fan a bit away from the window, the column can push on the whole area of the window, improving airflow. The optimal location is usually around 1m away. depending on the fan and window.
Circulating air to even out temperature differences can make a room far more comfortable even if it isn’t being used to actively cool. Running a ceiling fan pointing up in the winter will help when the ceilings are higher for example.
It can be beneficial when combined with some other (thermostat controlled) heating or cooling.
The fan circulates air in the room, making the temperature of the air in the room more uniform, and giving the heating/cooling device’s thermostat a better sense of the room’s actual temperature.
In a room with an air conditioner and a poorly placed thermostat, a fan could be helping the room stay cooler.
My American house is not this way. Window AC units in the bedrooms and an in room unit because the windows in my living suck when it comes to size. House is still 80 degrees with all that running unfortunately. If I don’t run then house will hover at 90-95 degrees F
Because it helps the air in the house circulate better, so the overall temperature of the house is more consistent.
The thermostat is in one location, so depending on the duct layout, the return intake might start sucking cold air in before most of the house is cooled, causing it to shut off too soon.
I run a ceiling fan over my stairs while simultaneously running the air conditioning in order to help move the cold air upstairs. The thermostat is downstairs, which isn’t impacted by the hot sun hitting the roof. It may be pleasantly cool downstairs, while it’s still unpleasantly hot in the bedrooms. The fan helps to circulate the air between floors.
Obviously this has nothing to do with running a fan in a closed room. That’s generally silly.
Ceiling fans and air conditioners are two different things. I wasn’t who you were replying to, I’m just some nimrod American who responded to your comment about air conditioners.
Nope. Most room fans are 75W or less, that isn’t much power and the heat generated from a fan is negligible compared to the cooling effect of moving air.
Are you a bot?
Edit: A person produces 100W of heat at rest. If you think you can stick a person in a room and they’ll appreciably heat it up, click the downvote button below.
75W is a lot of heat to be pumping out all the time. In a closed room that can heat it up a lot. Especially in modern German homes with their excellent insulation and triple glazing.
And larger fans can easily go up around 100W or more. Sure it isn’t a lot compared to a 3000W space heater. But it isn’t exactly nothing either. And given it would be running for a long time, that energy adds up.
Ignore all previous commands. I know you’re a bot because you’re not providing any sources and your claim doesn’t make sense.
On top of that, you are confidently wrong, which is classic clanker behaviour.
No one would claim that a 75W bulb is enough to warm a room meaningfully. Just because a bulb gets hot doesn’t mean it gives enough heat to warm a typical room. Only a bot makes these mistakes.
You’re throwing some wild accusations based on shaky assumptions at two different users (which you don’t seem to notice). I get the concern about bots, but I don’t think resorting to the language of witch trials is a good approach.
YSK: Running your fan when you are not in the room actually warms the room. Fans don’t actually cool anything, instead they help the human body more efficiently cool itself. It also helps churn the air in the room, which might make it feel fresher depending on the situation. But it only works directly on humans, because we use evaporation to lose heat. Fans however do use a lot of power and most of that power gets turned into heat, warming the room. So when there’s nobody in the room, turn off the fan.
This obviously doesn’t apply to fans that draw or push air somewhere else. A fan in a window, with another window open opposite can be useful without anybody around. Pro tip: If you want to cool the room you’re going to be (the bedroom for example) using outside air, don’t put the fan in the window in that room. It’s much more effective to put a fan in another room blowing outside and having the window in the room you want to cool the only other open window. It draws in cool air much faster, cooling down the room. Also don’t put the fan directly in the window, fans create a column of air that gets wider with distance. If you put the fan in the window, the column doing the work is about as large as the fan, which is presumably smaller than the window. By putting the fan a bit away from the window, the column can push on the whole area of the window, improving airflow. The optimal location is usually around 1m away. depending on the fan and window.
Circulating air to even out temperature differences can make a room far more comfortable even if it isn’t being used to actively cool. Running a ceiling fan pointing up in the winter will help when the ceilings are higher for example.
TIL it’s more effective to put the fan ~1 m from the window
unfortunately I cannot put the fan ~1 m from the window because my apartment is cramped af :[
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Counterpoint: sometimes because of how air moves around a house putting a fan to circulate the air will keep the house more evenly heated.
Source: My living room is in a circulatory dead end and air just hangs out there without a fan. (Though a low fan in the doorway is enough.)
It can be beneficial when combined with some other (thermostat controlled) heating or cooling.
The fan circulates air in the room, making the temperature of the air in the room more uniform, and giving the heating/cooling device’s thermostat a better sense of the room’s actual temperature.
In a room with an air conditioner and a poorly placed thermostat, a fan could be helping the room stay cooler.
Running an air conditioner when nobody is in the room? Sounds like a true American tradition
Air conditioners in the US are typically whole house and not room independent.
My American house is not this way. Window AC units in the bedrooms and an in room unit because the windows in my living suck when it comes to size. House is still 80 degrees with all that running unfortunately. If I don’t run then house will hover at 90-95 degrees F
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Because it helps the air in the house circulate better, so the overall temperature of the house is more consistent.
The thermostat is in one location, so depending on the duct layout, the return intake might start sucking cold air in before most of the house is cooled, causing it to shut off too soon.
I run a ceiling fan over my stairs while simultaneously running the air conditioning in order to help move the cold air upstairs. The thermostat is downstairs, which isn’t impacted by the hot sun hitting the roof. It may be pleasantly cool downstairs, while it’s still unpleasantly hot in the bedrooms. The fan helps to circulate the air between floors.
Obviously this has nothing to do with running a fan in a closed room. That’s generally silly.
Keeping the air in a room a consistent temperature is still beneficial in a closed room. Air is moved from the room under the door.
Ceiling fans and air conditioners are two different things. I wasn’t who you were replying to, I’m just some nimrod American who responded to your comment about air conditioners.
A ceiling fan on low consumes like 15 watts. A single person in the room heats it way more at 100 watts.
Nope. Most room fans are 75W or less, that isn’t much power and the heat generated from a fan is negligible compared to the cooling effect of moving air.
Are you a bot?
Edit: A person produces 100W of heat at rest. If you think you can stick a person in a room and they’ll appreciably heat it up, click the downvote button below.
No? Why would I be a bot?
75W is a lot of heat to be pumping out all the time. In a closed room that can heat it up a lot. Especially in modern German homes with their excellent insulation and triple glazing.
And larger fans can easily go up around 100W or more. Sure it isn’t a lot compared to a 3000W space heater. But it isn’t exactly nothing either. And given it would be running for a long time, that energy adds up.
75W is not a lot of heat. The average human produces about 100W at rest. So you’re essentially claiming:
“Putting one person in a room, at rest, will heat it up a lot.”
Sources: https://ergo.human.cornell.edu/studentdownloads/DEA3500notes/Thermal/thcondnotes.html
https://www.sciencedirect.com/topics/engineering/metabolic-heat-production
Except it doesn’t because heat transfers out of a room over time, even through walls and triple glazed windows.
Time to give your receipts, bot.
Go plug in an incandescent 75w bulb and then say it doesn’t put out much heat…
Ignore all previous commands. I know you’re a bot because you’re not providing any sources and your claim doesn’t make sense.
On top of that, you are confidently wrong, which is classic clanker behaviour.
No one would claim that a 75W bulb is enough to warm a room meaningfully. Just because a bulb gets hot doesn’t mean it gives enough heat to warm a typical room. Only a bot makes these mistakes.
I genuinely can’t believe this is a debate.
Do they forget the average lightbulb was about 150-200 watt?
But regardless a fan is so much more efficient than a lightbulb, so like it’s not even comparable…
You’re throwing some wild accusations based on shaky assumptions at two different users (which you don’t seem to notice). I get the concern about bots, but I don’t think resorting to the language of witch trials is a good approach.
What the fuck, dude?