Last Updated on May 3, 2023 by Barry Gray
If you live in a part of the world where heat is an issue, then having a ceiling fan in a room makes a lot of sense. However, have you ever sat there and thought more about the way in which a fan operates?
You see, a ceiling fan does sort of cool a room, but it doesn’t do it in the way people expect. Instead, it takes a different approach that still results in us feeling that the temperature in the room is significantly cooler than it was before we switched on the fan. Instead, it moves the air around while our body experiences something called wind chill resulting in us feeling cooler.
Yet, the reality is that a fan is not doing what we think it’s really doing, which is confusing when you dive into what’s going on. So, I’m going to spend just a short time explaining how a fan works and how it manages to make a room feel so much more comfortable than before you switched it on.
I promise it’s not going to end up working the way you anticipated.
But first, let me answer the question that makes the topic of this post.
Does a Ceiling Fan Cool a Room?
You see, the answer here is both yes and no, and I’ll explain why I’ve had to answer in that manner. After all, it turns out a fan is more complex than people realize.
In a sense, a ceiling fan does cool a room, but the “no” part of this answer is because some of it is connected to our body and the way we react to what’s going on. Yes, we play a significant role in all of this and are not simply innocent bystanders just waiting for the fan to work its magic and get us cool.
Think about a fan in your kitchen. You know it makes the room feel cooler, but do you know how it manages to do this?
To get to the bottom of this, I need to talk you through what goes on with heat, cool air, and the fan’s role in it all. You see, there are certain things about the heat that occurs in a room that a fan will then, in a sense, manipulate to make the room feel better.
Once you gain an understanding of that, then the way a fan works will become much more apparent.
So, that’s what I will focus on because a ceiling fan is way more interesting in its approach than people realize.
But first, let me clear up something that may lead to some confusion for some people, and it’s the difference between a ceiling fan and an air-con.
It’s Not An Air-Conditioner
I must also mention that a ceiling fan is entirely different from an air-conditioner unit. You may have thought that both are doing the same things, but that’s certainly not the case.
Your air-con will actually lower the temperature in the room. That’s what it’s designed to do. However, a ceiling fan works via something called the wind chill, and it’s this wind chill that does the apparent job of making the room cool.
But don’t make the mistake of believing that even the best ceiling fan will work the same way. It’s impossible.
Yet there’s another thing I must mention. A ceiling fan can also not do the same job as a window fan.
With a window fan, it pulls cool air through the fan and into the room while also helping hot air to move out of the room. This does actually help reduce the overall temperature in the room.
A ceiling fan does not do that. It simply moves the air that’s already in the room around to create the wind chill, which is something I’ll discuss next.
The Concept of Wind Chill
When talking about a ceiling fan, one thing that will come up time and time again is the idea of wind chill. You see, a ceiling fan uses this to create the impression that the room is cooler than it was before, and that’s vital to understanding its effectiveness.
The wind chill is something we experience with the weather. It’s when the movement of air across the body makes the body itself feel cooler, reducing the temperature of the skin and body in the process. A ceiling fan, or any fan for that matter, will use the same principles to make us feel more comfortable.
Think about the impact that even an outdoor fan can have. You are warm, stand under the fan and feel cooler. The air around you is still the same temperature, and yet the fan has managed to do something quite amazing, it has created that wind chill effect in the same way the natural wind will do to get you cool.
But to better understand that, we need to become aware of the concept of the actual movement of air. That’s because the way in which hot air and cold air act will differ from how it acts, and a fan uses this difference to its advantage.
The Movement of Air
So, I need to talk about the physics of air and what happens between hot and cold. This is crucial as it then helps better explain the way in which a fan works, and it will make sense of why a fan will do certain things.
The key thing a fan will do is to move the air that is immediately around it. That is primarily the only way it can operate, but it’s pretty darn good at what it does.
Now, the air that is around us is warmer than the air up by the ceiling. Hot air sinks lower down, while the cool air that is up by the fan can be a few degrees cooler than we are experiencing.
For that reason, a fan needs to work by pushing the cooler air down and allowing it to replace the warm air that is making us overheat. That is the way in which the room will, in effect, feel cooler to us as we are experiencing a different type of air from what we were used to.
But to do this, the fan needs to use force to push that air down and get the effect we are looking for. That is where the blades’ rotation and the motor’s power in the ceiling fan will play a significant role.
The Direction of the Fan is Crucial
So far, I’ve spoken about how a fan can make a room cool, but this is also thanks to the direction in which the blades on the fan are rotating. When they are spun the wrong way, a fan has the potential to also warm up a room, and if you are already feeling the heat, then that’s something you clearly need to avoid.
If you want your room to feel cooler, you must have the blades on your fan spinning in a counterclockwise direction. This then allows the fan to push the cooler air down, so the cool air then effectively sits around where you are rather than being pressed up against the ceiling.
But be aware that making your fan blades rotate in the other direction will result in it pulling up the cool air and, as a result, making the air feel warmer. You can see how that can prove to be problematic during the summer months.
This is where the concept of either an updraft or downdraft comes into play. You can see how the way in which the fan moves air around will play such an important role in how the entire room then feels.
But the direction of movement is not the only thing you need to think about when it comes to a ceiling fan. The size of the blades will also play an integral role in how effective it is at making you feel more comfortable in a room.
The Size of the Fan Also Makes a Difference
But here’s another critical point to consider: the size of the fan in relation to the size of the room.
It makes sense that a larger room will require a larger ceiling fan to get the same results as a smaller room. After all, it needs to contend with a lot more air, so it needs that blade size and power to even stand a chance of doing a good job.
The important part is the blade size and to also know the size of the room. This is something you can quickly calculate, and it’s an important step in being able to feel more comfortable. Let’s face it, you need a different size fan for your bedroom compared to a large open-plan living area simply due to the sheer size of the space.
For example, a ceiling fan with a blade size of up to 36 inches will be perfect for a room covering some 100 square feet. However, it won’t have the same impact if you try to use a fan with 36-inch blades in a room that even covers 150 square feet.
But don’t worry too much. Blade sizes do increase in size quite considerably. Actually, you can reach a blade size of 60 inches, but the most common large size is 52 inches. However, those blades are only to be used in rooms larger than 400 square feet in size.
Yet there’s another thing I need to mention.
If you have a room of 400 square feet in size or larger, you should look at installing more than one fan with 52-inch blades. That’s the best way to get that particular room feeling significantly cooler without putting the fan under too much pressure. Actually, it’s the only way you can achieve this.
To ensure you have the correct size of fan for a room, consider these measurements.
- A room up to 100 square feet – blade size from 29″ to 36″
- A room 100 to 200 square feet – blade size from 36″ to 42″
- A room 200 to 400 square feet – blade size from 42″ to 54″
- A room over 400 square feet – blade size of 60″ or 2 fans at 52″ each
The Role Your Body Plays in All of This
I’ve mentioned how a ceiling fan does not actually lower the room’s temperature, so how do you feel cooler? It feels so obvious that you are no longer as uncomfortable when the fan is in action, so clearly, something is going on that will make a difference.
Earlier, I spoke about wind chill, and this is also where your own body plays a significant role. Actually, it plays the main role in all of this.
The fan pushes the cooler air down to where we are in a room, and the movement of that colder air, which is the wind chill, but it’s also the speed of the air that plays a role.
You see, one way in which our body cools down is clearly through sweat. It’s the primary way in which we do it, but the movement of air against our skin also helps determine how much we then sweat.
As our skin encounters faster moving air, it speeds up the sweating process and allows more heat to evaporate from us. That’s why we actually feel as if the room is cooler, and it’s not because the temperature has actually dropped because of the fan. Instead, it’s because our body is reacting how it’s designed to when dealing with that faster moving air.
How Big a Difference Can a Fan Make?
It has actually been shown through various tests the difference a fan can potentially make to the temperature of a room. Well, it’s also partly built into our own perception of the change in temperature, so we need to take some of the credit as well.
Basically, a fan will reduce the temperature in a room by around 4C, and that’s a huge difference even though, for some people, it may not sound like much. Also, keep in mind it does help with humidity as well thanks to removing the excess moisture from the air.
At that change, you will notice that a room is distinctly cooler than it was before, and it shows how it doesn’t even have to be too big a difference for things to become significantly more comfortable than they were before.
The Advantages of Running a Ceiling Fan
So, I’ve already ascertained how a ceiling fan does make you feel cooler, but not via actually reducing the temperature in the room. However, there are a number of clear advantages of running a ceiling fan, and I think some may come as a bit of a surprise to some people.
It’s a Less Expensive “Cooling” Option
I know a fan doesn’t cool the room as such, but it gives you the feeling of being cooler, which counts for a lot. But do you know what else counts for a lot? The cost.
A ceiling fan is less expensive to run when compared to air con. So, if you do not live in a high humidity area, as humidity can change everything, then using a ceiling fan to make a room feel more comfortable makes more sense from a money perspective.
This is all because a ceiling fan requires significantly less energy to run compared to an air-con unit. This is obvious because you only need a small amount of energy to rotate a small motor, as it’s the blades that do the hard work. Air conditioning requires far more parts for it to work, and it all costs money.
It Does Help with Humidity
This point is similar to the temperature point in that a ceiling fan will not directly lower the humidity. Still, it will certainly make it significantly easier for you to be able to cope with the humidity.
This is because the ceiling fan will work the same way with humidity as with warmer air. It will help your body to sweat and cope with the humidity with this then making you feel less uncomfortable.
But if you checked the humidity in the room, chances are there would be little difference from before. However, that’s not what your body feels, and that’s the most important part.
Maintaining Your Ceiling Fan
Finally, you do need to consider maintaining your fan if it’s to continue to help you feel cooler. The main issue is dust gathering on the blades, and then the rotation will disperse that dust through the air. You can imagine how that’s not a good idea for anyone with allergies.
Long-handled dusters will at least help with the entire dust issue, and it’s something you should really look at doing weekly.
But if you are able to get up to the blades, then I also suggest wiping them down with a damp cloth several times a year. This will help keep the blades clean and stop any potential problems. Also, consider checking if any mechanism requires oiling to ensure it runs smoothly.
The only other piece of maintenance I would carry out, and I would only do this perhaps once a year, is to check the screws and bolts that hold the housing together, as well as the blades onto the fan. Over time, they can become loose, and you don’t want to run into those sorts of problems as it can damage the fan in the process.
Also, if any screws are not as tight as they should be, it will often lead to your fan making a lot of noise, and that will become very annoying in next to no time.
While checking the screws, I would also suggest adding some oil to the motor. This can be done via the oil hole in the housing, and it will just help keep everything moving smoothly and prolong the motor’s lifespan.
Aside from those few things, which do not take long to complete, there’s little else for you to do when it comes to your fan. Look after it correctly, and your fan should last a number of years without running into problems.
Some Facts Regarding Ceiling Fans
To round things off, I will sum up certain facts regarding ceiling fans that you may be unaware of. In the process, it may make it easier for you to gain a better understanding of how they work.
They Add Heat to a Room
This is a surprising thing, but a ceiling fan does actually add some heat to the room. Don’t worry, though, because it’s not really something you will feel unless you run the blades in the wrong direction to push the warm air around you.
But what I’m talking about is what a thermal image will show when it comes to a ceiling fan. The blades remain cool, but the thermal shot will show the motor and housing as glowing to indicate it’s emitting heat.
This is not really a surprise considering it’s something mechanical that is also rotating, so it will almost always conjure up heat. However, it does mean that, technically, at least, fans add some heat to the room when you simply want them to cool you down.
The Efficacy of a Fan is Important
If you are in the market for a new ceiling fan or any type of fan actually, then the efficacy of the fan is important.
The efficacy relates to how efficient the fan is at doing its job. It makes sense that you want a fan that’s as efficient as possible. With a fan, you should be looking at how high the figure is regarding the cubic feet per minute and per watt. This lets you know how much air is pulled through the fan in a minute, and ideally, it should be a minimum of 100 and nothing less.
But here’s an issue. Generally speaking, larger fans have better ratings which is an issue if you have a small room.
So, if you need to purchase the smallest ceiling fans around, then don’t drop below 30 because, at that point, it means the fans are just incapable of really doing anything positive for you.
Speed isn’t Important
If you thought that speed would significantly contribute to how effective a fan is at cooling a room, then you would be right. However, it’s perhaps not in the way you would expect.
Instead, a lower speed works best. Actually, a mid-range speed strikes quite a good balance between power usage and efficacy, so try to aim for that with your fan as the maximum speed. The higher the speed, the poorer the fan will then work, and you are simply wasting energy in the process as well.
A good fan will focus on pulling through a high volume of air but do so at a low speed resulting in a far more comfortable environment.
Basically, a fan is going to work better when you are aware of the sheer volume of air it can work with rather than raw power. If you have ever wondered why you see some ceiling fans in different establishments looking as if they are hardly moving, then this is the reason why. They basically understand exactly what’s going on and are getting the most out of the fan with the least amount of effort.
So, a ceiling fan will indeed cool a room but don’t forget the role your own body will play in making the room feel better than it did before.
A ceiling fan is clever in the way it tackles this issue, and if you do live in a part of the world where heat is an issue, then I would certainly have a ceiling fan installed. It’s a surefire way of making it cooler, but it does come with several issues that I mentioned earlier.
But there’s a whole lot more for you to learn regarding a ceiling fan, and I have a number of articles posted on this website all about this subject.