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. both directions. 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. Centrifugal fans normally only blow in the direction of the outlet as shown, while axial fans may be reversible in some cases. First I wanted to buy a new computer case fan in eBay. A heat sink that is both active and passive blows air through the finned radiator to help the heat escape faster.. Case fans. However, I am unsure as to what the air flow direction should be. 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? Fans generally only come in a few basic designs, most of which are axial or centrifugal types. The example is correct because the air moves forward if the fan blades rotate clockwise with the blade angle downward (moving from the front of the fan towards the rear). You can also look at the curve of the fan’s blades to determine how it’s carving the air, or spin by hand and feel for airflow. Likewise, if the blade is angled down and the fan turns the opposite direction, the reverse is true. Ordinarily, you’ll most likely find this on general-purpose fans like small DC powered fans for electronics cooling. You’ll need to rotate the fan 180° to change the air direction. It should draw air through the radiator from front to back. in this way, you'll achieve … I have 5 enormous fans constantly blowing away on my unit. Depending on the time of year, you'll want to change the direction of your ceiling fan so that it blows cool air around the room on a hot day, or distributes warm air on a cool day. It is an Akasa fan. 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. If the fan is not OEM, the air volume may be off and the electrical characteristics could be different. Right now, they are set as intake fans, so they blow air in, and not out. 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. Suck into the case, blow out. It’s really handy to remember method #1 above. Find out how much electricity an air conditioner uses vs a fan here. 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. I recently got a Cryo LX and it blows air onto the laptop, I want to try to mod it to have the fans spin in opposite direction. Though you might not expect to need to change a vent fan's direction, this could become a necessity. 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. Note: Some older and cheaper Power Supplies come with an 80mm fan at the rear. However, from time to time it can be found on others. You will also be able to identify the Exhaust side as you will see power wires entering the fan motor. 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. That just means that fans cool your body and your room by forcing air across surfaces, removing heat from you into the nearby air. I'm a do-it-yourself fanatic from Atlanta, Georgia. Yes, there are some fanless PSUs available too but they … 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). So, with that said, does anyone know if the direction the fan spins is a standard? They’re critical for everything from cooling a computer’s CPU to keeping us comfortable or even helping with plant grow rooms. In this video, I explain how to setup your cooling fans to create neutral movement air flow. Fans powered by alternating current (AC) such as common household 120V or 220V fans typically can only blow forward. I have replaced the evaporator fan of my refrigerator (Chinese generic brand). Air should travel in clear path through the case. Doing so allows you to reinstall it facing the opposite direction, thus changing whether it is "sucking" or "blowing." The clearance between the ceiling fan blades and the ceiling should be a minimum of 10 inches. Fans have a convex side and a concave side. How to determine the airflow direction of your case fans. You can test this easily enough with pretty much any fan. The direction of the PSU fan is crucial for airflow. If a blade is angled down and the fan turns in the same direction as the blade angle, it will blow forward. However the NH-D15S mounts the fan in the middle. As I'm sure any rockstar could tell you - the bigger the fan, the better the blow. To figure out whether your PSU fan needs to point up or down, start by looking over your PC case. Although your comment was rude and misplaced I’d like to respond in order to clear up your misconceptions. share. A fan blade is designed to run in one direction, otherwise it only moves about half of the air it should be. Remember to keep the blades nice and clean to keep the fan working at its best! save. This type of fan can rotate in both directions, without any change in fan power consumption and air volume. Since you only supply power, there is a controller in the fan that senses rotor position and commutates the motor accordingly. 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). Should the fans be set to blow air through the radiatior and out to the top of the case? Conversely, run a fan clockwise to amplify the heat from a fireplace or any other heat source in a room. Feel free to drop a comment below or reach out to me. I thought laptops had that type fan. In both cases, there are 2 arrows: one to show the direction of rotation, and one to show the airflow direction. If the direction was counter-clockwise, then yes it would be the opposite. Even tiny PC fans are optimized for aerodynamics and quietness. 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. Keep the fan direction in mind when you’re looking to cool down or warm up a room. I appreciate this site, but in the “every day example” you have of a PC case fan, isn’t that reversed? The way I think of this is to ask the question as to what is the leading edge of the blade as it rotates? Airflow through the case is important, so yes, it matters. I think the type of fan called a “centrifugal inline duct fan” would be the closest to what you’re describing. I often find that people don't explain how a fan works, and instead they just go off how fans are assembled, so I figured I'd add this: case fans will usually have a side shaped like the inside of a scoop. High heat build up, high head pressures, inefficient is an understatement. I currently have my swifttech 220 radiator with Yate loom Mediums sucking behind the radiator in to the case. Since the old fan was broken, I couldn't know on which direction it was set to run. It also depends strongly on the fan’s intended use as well. If you look at a PC fan case with directional arrows you’ll see it matches what I’m describing. 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. My goal is to help you enjoy a fresher home! Wanted to connect it only in hot weather. Here’s a helpful post with some of the best tower fans you’ll find today. Grab a small piece of paper and lay it across the fan when PC is on. It’s a great and cost-effective way to help you focus, relax, or sleep better. Secondly, the windmills take the direction of the wind no matter which side. This guide will teach you how to select the correct ceiling fan direction … A fan that blows air out of the case will blow the paper away from case. These two characteristics of a fan are probably the easiest and most common way to tell which way it blows. You want both fans on the radiator going the same direction. Want to know how much energy a fan can save? Some fans will have arrows on the side pointing in the direction that air flows through them when turned on. A fan that blows air out of the case will blow the paper away from case. A side effect of how they work, the noise “masks” (covers up) outside noises like your neighbors, traffic, people talking, and more. Be sure you’re using fans to improve your quality of life (and save money) as much as possible! https://www.maketecheasier.com/intake-exhaust-fans-airflow-desktop-pc The direction of air movement for a fitted fan can easily be confirmed with a slither of paper. Determine where the PSU is intended to fit; this is typically at the bottom of the case in most modern chassis designs. They work off of the principle known as forced convection. posted 2007-Jul-24, 8:24 pm AEST They spin with the pointy end of the blade cutting the air first. 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'. Do they make a fan (like the Centrifugal) that blows downward and the intake is from the side, not the top? 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. Airflow will always flow from leading edge to trailing, just like the wing on an airplane. I just came across your site and appreciate the site also and wanted to ask a question. The instruction manual of the fan will also tell you how to change the ceiling fan direction for that model. 23 posts - 20 authors - Last post: 24 Jul 2007How do you tell which way a fan blows?. Once you’ve located where the PSU will sit, check the case for any grills or vents directly beneath this location. Fans are also very helpful in some cases for blocking outside noises that cause us stress and interrupt sleep, studying, or working. 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. Therefore, unless the power polarity is reversed, it will blow air forward. Close. 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. Left: This fan is the most common type, as it can be mounted backward if you need to reverse airflow. However, I am unsure as to what the air flow direction should be. Spinning this way the fan then pushes the air ahead of it. A ceiling fan that spins clockwise will draw cooler air up and force warmer air near the ceiling down and out toward walls. How can I change a fan from suck to blow? 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. 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. This causes air to blow upwards (to the front of it). Being able to tell which way a fan blows isn’t difficult in most cases. To figure out whether your PSU fan needs to point up or down, start by looking over your PC case. Once you’ve got the basics down it’s not hard at all! The unobstructed side, where you can see the whole fan blade and logo in the center, is the intake side. (can't test as waiting for motherboard). 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. 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? If a blade is angled down and the fan turns in the same direction as the blade angle, it will blow forward. Not only that, I’ll help you better understand how fans work along with sharing some helpful facts to know. If the fan has a sticker, the airflow probably goes from the other side to the side with the sticker. Hello Tony. Box fans are especially helpful for this. I can’t stop laughing, an article which trying to teach other people, had it wrong itself. I'm debating flipping the exhaust or CPU fan, but like I said, I cannot tell which direction it's spinning. While it’s not as common, some fans do have a marking indicating which way they blow. So you mount the fan in the direction you want the air to go. How can I know on which direction should I set the new one to run. The direction of the PSU fan is crucial for airflow. Here are some great fan facts to know. If not, or if you want to be sure, turn the computer on with the fan connected, and put a piece of paper against it to see if it blows away or gets pulled to it. There are several options for how a CPU cooler can exhaust heat from the CPU. Archived. So on a 3 pin connector, do I just switch the places of the left and the right pin? It should draw air through the radiator from front to back. The side of the fan that has the support structure to hold the motor and wires going to it is the output side. Heat sink and CPU fan. When looking at our fans, the Front or Intake side of the fan will always be the side that has the Cooler Master Logo in the center of the blades. Generally, you want the case fans in front of the case drawing in air while the fans at the rear blow air out. 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. hide. Further queries wind Curve at Amazon are an excellent example of some common fans with markings to show direction. That blows air through the finned radiator to help you better understand how fans work with... The manufacturer to decide which way it blows from the front of it ) in my should! Continual effect that makes you more comfortable the evaporator fan that has the structure... Yate loom Mediums sucking behind the radiator come with an 80mm fan the! 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