but basically you should have fans that blow cool air in and fans that blow hot air out. report. Try to keep the air flow in your case going in one general direction, with more fans blowing in that blowing out. The unobstructed side, where you can see the whole fan blade and logo in the center, is the intake side. Although your comment was rude and misplaced I’d like to respond in order to clear up your misconceptions. If you’re lucky enough to find that on one, it makes it even easier to tell! If the fan is not OEM, the air volume may be off and the electrical characteristics could be different. Now obvious, winds don’t blow from both directions right? Airflow through the case is important, so yes, it matters. I have replaced the evaporator fan of my refrigerator (Chinese generic brand). some of the best box fans for white noise you can buy. I thought laptops had that type fan. Not only that, I’ll help you better understand how fans work along with sharing some helpful facts to know. You cannot reverse the direction of the fan externally by simply reversing the polarity of the power. As the fan spins, it can be thought as chopping at the air. Models that produce a very high airflow rate and introduce a lot of turbulence near them as a side effect can produce a large amount of soothing white noise. Hello Tony. In simple terms, a computer case can either have: Positive pressure – The case fans push more air into the case than then pull out, so there is more air pressure inside of the case. I asked the same question of myself when I wanted to mount an additional fan inside a side vent on the PC case to blow air on the nearby graphics card. A heat sink that is both active and passive blows air through the finned radiator to help the heat escape faster.. Case fans. But....I have rotated the fans now roughly 20 times, but nowhere does it show arrows indicating the airflow. Air will blow in the other direction (towards the back). Coming home to fresh, clean air is fantastic and I want to help you enjoy the same. I tried looking at it upon startup, but it spins so fast, so qucikly, that I cannot honestly tell which direction it's going. Some fans will have arrows on the side pointing in the direction that air flows through them when turned on. Be sure you’re using fans to improve your quality of life (and save money) as much as possible! The wisest course is to remove the fan and install a GM supplied part. If a fan has its voltage reversed or is designed to rotate in the other direction then yes, the airflow can be reversed. Stand directly beneath the ceiling fan while it is running. I just came across your site and appreciate the site also and wanted to ask a question. AFresherHome.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com. AFAIK, most 80mm fans have an "arrow" imprinted somewhere on the fan housing which points the direction of airflow Quick rule of thumb: the fan will blow the air across the motor 'always'. A heat sink on the processor or any other internal cooling unit, can suck or blow depending on the make of the heat sink and configuration of the computer's interior components. Neutral pressure – Air pressure in the case is equal to air pressure outside of the case. Spinning this way the fan then pushes the air ahead of it. I apologize for some of the rude comments. The direction of rotation Which direction is the evaporator fan supposed to spin? If not, I’d love to show you how. A simple but classic box fan like this popular Lasko 3720 model produces a soothing and calming “white noise” that can improve your quality of life. Air should travel in clear path through the case. Perry, To make it short, Yes, the evaporator fan should be blowing the air into the freezer compartment. Doing so allows you to reinstall it facing the opposite direction, thus changing whether it is "sucking" or "blowing." Note: Some older and cheaper Power Supplies come with an 80mm fan at the rear. They’re helpful for many common uses and problems, but there are some things you might not know about them. Would it pull the air from the back or from the front? They work off of the principle known as forced convection. I can’t stop laughing, an article which trying to teach other people, had it wrong itself. If you look at a PC fan case with directional arrows you’ll see it matches what I’m describing. If that doesn't work, try holding a tissue paper or something else breezy up to the fan - If it gets sucked towards the fan, it shows you that the fan is intaking from that direction, and if it blows outward, then it's exhausting air. However the NH-D15S mounts the fan in the middle. Fans are also very helpful in some cases for blocking outside noises that cause us stress and interrupt sleep, studying, or working. If you can get in there, you can probably reverse the direction by flipping two of the three sensors and two of the three windings. Here’s a great example of how to decide which way a fan blows. Close. It is an Akasa fan. It’s a great and cost-effective way to help you focus, relax, or sleep better. In this video, I explain how to setup your cooling fans to create neutral movement air flow. You will also be able to identify the Exhaust side as you will see power wires entering the fan motor. That’s because DC power can change the operation of the electric motor inside the fan, causing the blades to spin in the opposite direction and force air to the rear. Likewise, if the blade is angled down and the fan turns the opposite direction, the reverse is true. Here’s an animated image I’ve put together to help show this. In this image you can see exactly what I’m describing: the fan is rotating in the same direction as its blades which are angled downwards. The fan at the bottom of most laptops blow air out, so wouldn't a cooler that blows air onto the laptop work against the laptop fans? Determine where the PSU is intended to fit; this is typically at the bottom of the case in most modern chassis designs. Therefore, unless the power polarity is reversed, it will blow air forward. This is a common small fan powered by direct current (DC) and used for many electronics cooling applications. some of the best tower fans you’ll find today. The fan’s purpose is to give additional airflow when the vehicle is moving slowly- at high speed, the forward motion of the vehicle pushes enough air through. Determine where the PSU is intended to fit; this is typically at the bottom of the case in most modern chassis designs. This forced the fan to "suck" air through the radiator. Does It Matter Which Room You’re In? Before the advent of electrical fans for cooling radiators, the mechanical fan was exclusively driven by a fan belt attached to the front of the engine. You want both fans on the radiator going the same direction. Want to know how much energy a fan can save? A fan that blows air out of the case will blow the paper away from case. This causes air to blow upwards (to the front of it). Even tiny PC fans are optimized for aerodynamics and quietness. 2. Common PC case (and other) fans are not standardized. In arrow located on the side of the fan indicates the direction of air flow. Centrifugal fans can only blow air radially outwards. Or, you could watch the fan as your computer is powering off (the fan accelerates too fast due to electricity as it's starting up which makes it impossible to tell unless you're Ted Williams, but when it's slowing down, it's just friction and some magnets). An overhead fan can create a relieving breeze or recirculate heat during cooler months—if you know how to change the ceiling fan direction. When looking at the fan so that the circular sticker with the Noctua logo is facing you, the direction of airflow is towards you and the sense of rotation is clockwise: . I currently have my swifttech 220 radiator with Yate loom Mediums sucking behind the radiator in to the case. You will also be able to identify the Exhaust side as you will see power wires entering the fan motor. Keep the fan direction in mind when you’re looking to cool down or warm up a room. Front fans should be sucking cool air in (arrow towards MOBO), rear fans are obviously exhaust (blowing out, arrow facing the back of case), and side panel fans are dependent upon location. No. Box fans are especially helpful for this. Here’s a helpful post with some of the best tower fans you’ll find today. Heat sink and CPU fan. Making assumptions based on which side of the fan has plastic bars on it isn’t the right way to determine it, but is instead, guessing. both directions. Right now, they are set as intake fans, so they blow air in, and not out. Perhaps you're in the middle of renovations and need to change the flow of air or the motor to the fan broke and the replacement arrived rotating in the wrong direction. (the side with the guard/motor support) Lastly, the fan airflow can be identified by the arrow markings on the fan housing. However, direct current (DC) fans are often reversible. However, from time to time it can be found on others. They’re different from other types as they produce a tall, vertical area of air and often oscillate (move side to side) to cool a room. hide. You can test this easily enough with pretty much any fan. If if higher on the side it's probably meant to exhaust while a low side fan is probably meant to suck in cool air and blow it on the MOBO. share. One set of twin fans sucks while another other set of twins blows. The direction of the PSU fan is crucial for airflow. Using the fan angle and rotation direction, Airplane propellers and jet engines always force air from the front to the rear, Ceiling fans are normally used for blowing air downwards into the room but can be reversed to force air to the ceiling, High-speed cooling fans of the centrifugal type blow forward, Home cooling fans normally blow forward and can’t be changed, Ventilation fans are mounted in a wall, window, or other assembly and spin to blow air out of a building, The power source type (AC or DC) and intended use. Hi Bobby and thanks for dropping by. Need to cool out? However, I am unsure as to what the air flow direction should be. Changing the direction of your ceiling fan in the summer and winter not only makes you feel comfy, but it also allows you to adjust the thermostat and give your AC or heating unit a much needed break (your wallet will also get some much-needed rest, trust us). Then I thought of putting a computer fan on the desk for hot summer days but I couldn't tell from the picture in which direction the fan would rotate. The other side will be doing the opposite and will suck your hand in. Alternatively, you can plug the fan in and place a tissue on a side of the fan to determine the direction of air flow. How can I tell which sides expelling air? Works a treat with fan pulling air into case onto graphics card. The side of the fan that has the support structure to hold the motor and wires going to it is the output side. The example shown most certainly is correct. Airflow will always flow from leading edge to trailing, just like the wing on an airplane. Once you’ve got the basics down it’s not hard at all! This type of fan can rotate in both directions, without any change in fan power consumption and air volume. If not, I’m thoroughly confused. Everyone deserves a healthy and enjoyable home environment. 2 Observe the direction the fan blades are turning. How can I know on which direction should I set the new one to run. If a blade is angled down and the fan turns in the same direction as the blade angle, it will blow forward. The image above is a great example of a common fan you might run across. It’s best to run the fan on a low speed so that it doesn’t create too much of a cooling breeze. That’s because fans don’t need nearly as much electric current to work. Do they make a fan (like the Centrifugal) that blows downward and the intake is from the side, not the top? Here are some great fan facts to know. It is an Akasa fan. To figure out whether your PSU fan needs to point up or down, start by looking over your PC case. You can see the blade shape in the picture which gives a clue about this as well. Since you only supply power, there is a controller in the fan that senses rotor position and commutates the motor accordingly. Thread starter devilchrist; Start date May 9, 2008; May 9, 2008 #1 D. devilchrist Weaksauce. As I'm sure any rockstar could tell you - the bigger the fan, the better the blow. Air conditioning (AC) units not only have to power an electric fan but also an energy-thirsty refrigerant compressor motor. if i reverse them, will it change direction? Iamanerd2 02-14-2013 01:08 AM Reversing the direction of rotation will be difficult. Remember to keep the blades nice and clean to keep the fan working at its best! That’s because a fan always has the same basic design in one form or another: fans use angled and slightly curved blades to cut through the air and force it forward or backward depending on the direction of rotation. Joined Jan 13, 2008 Messages 74. If you want the fan to cool the liquid running through the system the fan pulls (sucks) air through the surface area fins to dissipate heat. PSU or Power Supply Unit is one of the most important components of a PC because it is the only component that provides power to all your internal computer components that include a processor, motherboard, hard drive, SSD, graphics card, case fans, etc.It can get hot during load and for this, it comes equipped with a fan for cooling. Grab a small piece of paper and lay it across the fan when PC is on. Bi-directional fans A “bi-directional fan” has straight blades, perpendicular to the shaft, which may or may not extend to the boss (inside section of the fan that holds the fan on the shaft). (can't test as waiting for motherboard). You can see the PSU airflow in the diagram given below. Generally, you want the case fans in front of the case drawing in air while the fans at the rear blow air out. The built-in electronic circuit manages "commuting" the magnetic field that causes the rotor to turn. While many variations of fans exist, nearly all fall into just a few basic categories as the most important design principles are the same. Ideally, your computer should suck and blow at the same time. Wanted to connect it only in hot weather. Do not mount exhaust fans on the bottom of the case; since hot air rises, a bottom-firing exhaust fan will be working against physics by expelling slightly cooler air instead of warmer air. Archived. As I have also advised many times. How to tell which direction fans are blowing. If it’s moving clockwise, wouldn’t the air move from the front of the fan to the back (in this picture) since the blades would “‘scoop” the air from the front? Of course, if for some reason the fan rotates in the opposite direction (unbeknownst to me) the air would be blown the other way. Even tiny PC fans are optimized for aerodynamics and quietness. The fan should blow air toward the engine (i.e., same direction as the air flow when the vehicle is in motion). alot of times it doesnt matter which way the fan goes, but just put it to blow air towards the heatsink if you're not sure. How to determine the airflow direction of your case fans. I used an Universal Evaporator Fan that can run both in a clockwise or anticlockwise direction. Fortunately, it's usually possible to reverse the direction of a vent fan using some basic tools. A fan blade is designed to run in one direction, otherwise it only moves about half of the air it should be. Great article. A fan in the front should generally blow air into the case, while a fan in the back. I mounted the fans now, but have no idea whether it is exhaust or intake. The direction of air movement for a fitted fan can easily be confirmed with a slither of paper. Air conditioning units do so by removing heat from the air. Standing alone, the blow side of a fan does produce a more concentrated, faster moving, and more turbulent "river" of air compared to the intake side where air is drawn almost equally from all directions. Conversely, run a fan clockwise to amplify the heat from a fireplace or any other heat source in a room. I'm debating flipping the exhaust or CPU fan, but like I said, I cannot tell which direction it's spinning. Question- I have the corsair H110 mounted EXACTLY as shown in the picture, (top-mounted) with the fans mounted to the bottom of the radiator. Tower fans are specially designed to produce a comfortable airflow. The way I think of this is to ask the question as to what is the leading edge of the blade as it rotates? Should the fans be set to blow air through the radiatior and out to the top of the case? In fact, I personally verified the information and examples in this article with actual fans rather than make assumptions as you did in your comment. For instance, run the fan counterclockwise if an oven heats up your kitchen beyond what’s comfortable, or body heat from a gathering of people makes a room too toasty. The Rear or Exhaust side (the side that the air comes out of) of our fans will always be the side that houses the fan motor. Here are 3 ways to tell which way a fan blows: The direction a fan blows air is always determined by (A) the shape of the blades (sometimes called propellers) and (B) the direction they turn. It also depends strongly on the fan’s intended use as well. Copyright © Copyright © 2017-2021 AFresherHome.com. By looking at the fan and knowing which way the blades are angled, and knowing that it normally turns clockwise, I can see that it will blow air forward. Firstly, the wind normally blows only in one direction IF you’ve noticed. Question- I have the corsair H110 mounted EXACTLY as shown in the picture, (top-mounted) with the fans mounted to the bottom of the radiator. So on a 3 pin connector, do I just switch the places of the left and the right pin? By simply adjusting your ceiling fan direction, you can warm your home in those frigid winter months. A fan’s direction is often fixed and largely determined by what it was designed to do: Most common home fans used for cooling like this Lasko 3720 window box fan are designed to blow only one direction: forward. The fans that I’ve seen in laptops so far resemble a traditional centrifugal fan. The direction of air movement for a fitted fan can easily be confirmed with a slither of paper. Likewise, if the blade is angled down and the fan turns the opposite direction, the reverse is true. posted 2007-Jul-24, 8:24 pm AEST They spin with the pointy end of the blade cutting the air first. Infographic – Fan facts and airflow basics, How to tell which way a fan blows – 3 basic methods. By changing the direction a fan is mounted, it can act as either an intake or exhaust. Exhaust fans go on the rear or the top. Once you’ve located where the PSU will sit, check the case for any grills or vents directly beneath this location. should the fan blow air into the freezer or draw air into the coils? To determine which is the correct orientation for the fan, observe the location of the manufacturer’s sticker on said fan – that’s the direction into which the air is blowing. Left: This fan is the most common type, as it can be mounted backward if you need to reverse airflow. From further up in my article you can see that it’s because fan blades “push” air upward when they rotate in the direction the lower end of the blade is facing. I see air filters all that time that have been installed backwards. If you’re interested in finding out more, here’s a great post with some of the best box fans for white noise you can buy. They’re critical for everything from cooling a computer’s CPU to keeping us comfortable or even helping with plant grow rooms. Of course, be careful not to allow your fingers to snag in the fan … A fan that blows air out of the case will blow the paper away from case. https://www.maketecheasier.com/intake-exhaust-fans-airflow-desktop-pc Keep the fan direction in mind when you’re looking to cool down or warm up a room. Ceiling fans are the must-have home appliance for summer, but did you know that ceiling fans are also handy in the fall and winter? The direction a fan blows air is always determined by (A) the shape of the blades (sometimes called propellers) and (B) the direction they turn. The Rear or Exhaust side (the side that the air comes out of) of our fans will always be the side that houses the fan motor. First I wanted to buy a new computer case fan in eBay. Fans powered by alternating current (AC) such as common household 120V or 220V fans typically can only blow forward. Ceiling fans should hang between seven and nine feet from the floor. save. it does matter. Lastly, the fan airflow can be identified by the arrow markings on the fan housing. You can expect that side of the fan to be the exhaust side. Fans can make you feel cool and comfortable as well as cycling the room’s air to prevent heat from building up. If a blade is angled down and the fan turns in the same direction as the blade angle, it will blow forward. High heat build up, high head pressures, inefficient is an understatement. A heat sink that is both active and passive blows air through the finned radiator to help the heat escape. 8 comments. But do you know how to tell which way a fan blows? Fans have a convex side and a concave side. you can have the front end blow cool air in, while the back fans blow hot air out. It’s really handy to remember method #1 above. It should draw air through the radiator from front to back. Ceiling fans help cool people in summer by producing a wind-chill effect as the fans circulate air downward. The Intake-exhaust direction should go front-to-back and bottom-to-top. If the fan has a sticker, the airflow probably goes from the other side to the side with the sticker. There’s no kind of assumption to be made in many cases like “the side with plastic bars connecting the motor to the frame” as this is incorrect. How do most people have it? The angle of the fan blades. Secondly, the windmills take the direction of the wind no matter which side. That way you can tell which way a fan blows nearly 100% of the time and especially if one isn’t marked with arrows or a label to tell you. Fans are typically not very expensive but can be very cost-effective in many applications. Just remember these basic tips: Do you have suggestions, more questions, or wish I covered some topics in more detail? If the fan’s direction is reversed, the air will go the opposite direction as it would be forced downward (towards the rear) instead of the front. Because of how they work (and how most are designed) there are great clues to help. Ceiling fans help circulate cool air and cut energy costs during the summer, but they are also helpful during winter months. Here the rear 80mm fan works as an exhaust fan for the PSU. The only problem is i cant remember which way the rear case fan was facing. Yes it would be the opposite direction, suck or blow, in out! I think of this those frigid winter months find today fans powered alternating. Air pressure outside of the fan airflow can be identified by the principle known as forced convection post... Will suck your hand how to tell which direction a pc fan blows front of it by producing a wind-chill effect the... Should generally blow air in, and not out fans to create neutral movement air flow direction should.... While another other set of twin fans sucks while another other set of twins blows most chassis. Case is important, so yes, the fan indicates the direction of case. 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