Name: Fans for Rear Door Heat Exchangers: Extending Air Cooling for AI-Era Data Centers | Presented by Sager
Uploaded: 2026-10-14T15:15:40.271Z
Duration: 39 min 36 s
Description: Fans for Rear Door Heat Exchangers: Extending Air Cooling for AI-Era Data Centers | Presented by Sager

Transcript for "Fans for Rear Door Heat Exchangers: Extending Air Cooling for AI-Era Data Centers | Presented by Sager": Hello, and welcome to Thermal Live Fall twenty twenty six. I'm Curtis Honeycutt, your host for this packed two day event brought to you by Electronics Cooling. Today and tomorrow, we're bringing together thermal management professionals from all over the world to explore the latest developments and and to connect with peers. We have a packed agenda of technical sessions, product demos, and expert insights. And we had a great response for our data center cooling days event back in July, and many of the sessions over the next two days will tackle thermal management challenges in the data center industry. These conversations are crucial and they are as timely as ever right now. Now real quickly, a few notes about the chat area. We want you to use it. For general chatting, use the chat tab. Go ahead and give it a try. Let us know where in the world you're joining us from today. And as your questions come up during sessions, please type them into the q and a tab to the right of the chat tab. This will allow presenters to address questions during the q and a at the end of their sessions. Now let's get things started. Our first session will explore how rear door heat exchangers can remove excess heat at the rack level to extend the viability of air cooled data centers. Drawing on real world design considerations, this presentation offers engineers practical guidance on fan selection and thermal management for next generation facilities. Our first presenter, Vineet, is the technical support manager for thermal products at Sager Electronics, bringing over fifteen years of design experience and two patents to his role. And our second presenter, Steven Baristecki, is the director of information technology and cleanroom air technologies at EBM Pabst Americas, where he leverages over thirty five years of experience in electronics cooling to develop solutions for ever evolving markets. Sager Electronics provides engineers with practical guidance and advanced air cooling solutions designed specifically for the rapidly growing data center market, and EBM Papst is the global leader in heating and air movement technology, developing solutions for the IT, telecom, clean room, and air purification markets. Now get your questions ready, and please welcome Vineet and Steven to Thermal Live fall 2026. Take it away, guys. Hi, everyone. Thank you for joining our webinar. Today, Steve and I are gonna be talking about fans for rear door heat exchangers. So I'll tell you a little bit about SEGGER Electronics, and then Steve will tell you about EVM PAPS. And then I'll dive into data center cooling generally, and specifically how we get to the rear door heat exchanger as one of the solutions for data center cooling. And then Steve will tell you all about the EVM PAPS solutions that go into your door heat exchangers. A little bit about myself. I've been in the thermal management industry for fifteen years doing design work for heat sinks and cold plates. And then I've been at Sager for about five years helping customers find the right components. So whether those are the heat sinks, thermal interface materials, or air moving products like fans and blowers. Sager is one of the oldest distributors in North America. We were founded in 1887. And, through recent acquisitions, we've grown to a company of 422 employees with 10 service centers across North America and over 90 authorized suppliers. We have a large facility in Lewisville, Texas. It's a 175,000 square foot building that houses both a distribution center and our custom solution center. We use the custom solution center to do value added services for power supplies, batteries, and for thermal solutions where we do cutting of thermal interface materials, so heat sinks, cold plates. And then, of course, for fans, we add connectors, put it into fan trays, and do other value added services. Thank you, Vineet, and thank you to all of you joining us here today for the fall session of ThermoLife. A quick background, on myself. I've been with EBM Paps now for just over eighteen years. I've been in the EBM and electronics cooling universe, though, for just over thirty five years. After graduating from Northeastern University in Boston, I worked as a thermal engineer for a handful of IT telecom OEMs. During those years, one of my primary responsibilities was to qualify heat sink and fan suppliers. So this is how I got to know EBM, their people, and their products so well. I feel like I've been in their universe basically my entire adult life because I have. In my current role, I work with our customers, our sales team, our applications engineers, and the r and d team in Germany on finding best thermal solutions and developing new products that meet our customers' needs, most of which are in the IT telecom and data center space. At least for me, they are. Engineering a better life. This is our this is our corporate branding, with our brand claim, we express how important it is to us to implement sustainable and intelligent solutions that create a better climate for people, their applications, and our environment. Okay. Some specifics on the company. This is our global footprint. You can see three main areas, The Americas, Europe, and APAC. As you can see on the upper right, we have, 27 different, manufacturing production sites around the world, close to 50 sales offices in over 40 countries. A closer look into The Americas shows our manufacturing, presence in The US. We have two manufacturing facilities. One is at our primary headquarters in Connecticut. The other is in Telford, Tennessee, which has now been open for just about, I want to say, six or six years or so. We also have sales offices in Mexico, Brazil, and Argentina. Forward to some financials and metrics on EBM Papst. Last year, our sales were just over $2,500,000,000. Of that, 126,000,000 go back into investments in the company. Another 163,000,000 go back into R and D investments, which is very important because it helps us in our development. We're constantly developing new products, and that's why. We've had steady growth, over the past several years. Last year, it was 12%. Globally, we employed just over 13,000 people, and last year, we had 28 patents, which were, issued. Back to Vineet. Yeah. And so I'm I'm proud to say that Sager Electronics and EBM Pap have been partners for many, many years. We are EBM Pap's largest distributor in North America, and we were their first certified value added reseller for the custom solutions facility that I talked about earlier. We hold $3,000,000 of, EBM Pap's inventory that service 500 different OEM and CEM accounts. Okay. So let's get into data centers. So everybody knows about data centers, and we've known about them for many years. But a simple chat GPT query, so this is when people talk about inference for AI, uses 10 times as much power as an old school simple Google search used to. And by 2030, we're expecting exponential growth of AI data centers, and it's estimated to increase data center power by a 160%. Now, what happens to all that power? Of course, it's used to give you the chat GPT answers, but a lot of that physically gets converted into waste heat. So now we need strategies for cooling them. But like I said, we've had data centers for many, many decades, and we've gotten better over time about how to cool it. So we have a lot of different strategies on cooling these. Well, when they were at three kilowatts and five kilowatts per cabinet, you know, we knew how to cool them. We're getting to really, really high, almost absurd levels of power at 50, 75, 100 kilowatts of power. And for a lot of that type of power, you do need to go to liquid cooling or somewhat hybrid cooling, where your CPUs and GPU's are being cooled directly by liquid cold plates. And some of your smaller components maybe are cooled by air. But, not everybody's ready to switch fully to liquid cooling. There's a lot of complications that come from that. And so that's why we're... Today we're gonna talk about, active and passive rear door heat exchangers. So what is that? If you're somebody who has a data center and you're finding, okay, the next one that you're building has a really high density rack, I can't copy and paste the thermal cooling strategies that I used to use into the new one. Well, if you can go to fully liquid cooled and you have facility water, then you get a liquid to, air type CDU, or liquid to liquid if you have facility water. And then you go... Your server is, using cold plates. And if you don't have one, maybe you get a chiller. But if you're not ready to fully switch over to liquid cooling with all of its complications, you can use a rear door heat exchanger. And why might you use that? So let's talk about how a rear door heat exchanger works. It's a device that mounts to the back of your rack, and its job is to take the hot air that's being exhausted, from the back of your of your, cabinet and cool it back down to as close to the initial ambient temperature as possible. And the reason for that is, you saw the charts that I was look... I was showing you before. When you have a room HVAC system at three kilowatts or five kilowatts, maybe you can handle it. But when you start getting into 30, 40, 50 kilowatts, well, your room facility can't... Just can't handle that much heat being dumped. So, yeah, you might have the appropriate fans on your servers, and it'll give you the CFM, and it'll pull all the air through. But once the hot air is being dumped into the room over time, the ambient temperature will increase as a a track can't keep up with it. So the rear door heat heat exchanger uses liquid, whether that's from a coolant distribution unit that has a facility water on one side or a chiller, and then it works as a standard liquid to air heat exchanger or radiator to cool that hot air back down towards the ambient temperature. Steve? Okay. Get queued up here. Alright, so I really like this slide, very much. It's kind of the the inside view of a typical data center. And as you can see in all these simple box callouts, every single one of those boxes is a place where an EVM PAPS product could be used, which is... It's staggering when you think of it. I I recently did a a GROC search on how many fans are used in a typical data center, and it's anywhere from 500 to 700,000 fans, which is amazing. This particular Thermolive discussion today is gonna focus on rear door heat exchangers, which you can see circled there in the lower left. But if we had to talk about all these other segments, we would be here for probably the good part of a day. So, on to rear door heat exchangers. How about the market? According to the Insight Analytics, this chart shows steady and healthy growth of the rear door heat exchanger market for at least the next ten years. I can tell you personally this this data is backed up based on my own personal experience and involvement with the multiple railroad heat exchanger projects we are currently working on now here at eMAM Pabst in The US, and I know our colleagues around the world are as well. Vineet? Yeah. Thanks, Steve. So I wanted to tell you guys generally about... Now that we know rear door heat exchangers and we know about the market, you know, we get a lot of customers asking us about upstream decision making. So what kind of fans should we choose? How do we even start about this process? So fans fairly, commonly are divided into axial and radial, and I'll tell you nine times out of 10 for rear door heat exchangers, you're gonna be using an axial fan. It's the simplest. It's easy to mount. It's easy to understand. It's great for straight through airflow from the front to the back. But there's one small downside, which is it doesn't have the same static pressure capability as a radial fan. And a radial fan is one, as you can see in this photos, where the air comes in through, the center and goes out radially. And that does tend to have a higher static pressure and a higher PQ curve. But like I said, it's a lot harder to implement. So you want to make sure that all the fans are arranged in a way that, the airflow is efficiently coming in from the front and going out the back. And that's the reason why, like I said, nine times out of 10, axial fans are used for rear door heat exchangers. So the next question is, okay, I'm gonna use an axial fan, but what kind of fan size should I choose? Well, a lot of these applications, redundancy is super important because you wanna make sure your data center does not go down for service, if there's some small component failures. So if redundancy is the most important thing for you, and, you know what level of redundancy you want based on the life cycle of the fan and how long you want your data center to be operational for, then you may go with smaller fans so you can get more of those fans into your system. But, smaller fans also create a lot of noise. And so you may wanna go with a larger fan, that just reduces the noise. A lot of this does end up back into what is your system impedance? What is your requirement? And you end up down selecting from there. One of the other other things to talk about, obviously, is what is your input voltage? So a lot of these fans are available in both AC and DC input voltage. Twenty four and forty eight volt DC are the most common ones, so I'd recommend choosing one of those because you'll have the widest option, and widest selection to choose from. As you know, data centers, a lot of them are going to higher DC voltage architecture so that it reduces the power loss. And, some of those higher voltage ones are coming out in the market, and they are under evaluation by the EBM PAPs team. So looking at some of the other functions and features, what's common is modbus protocol for communication, hot swappability, and PWM fan speed. So if you want those things, those are included in most EBM paths fans. Something that's less common is ingress protection. Now ingress protection, when I think about that, I'm usually thinking of an outdoor application where you have to make sure things are still running or at least not breaking down because of the weather. While many of these fans are available in the higher IP ratings, so that's IP 54, IP 68, I wouldn't recommend necessarily choosing it just as a nice to have. And a big reason for that is because ingress protection in fans is done by encapsulating the motor, and that prevents dust and liquid from going in... Inside there. It's great, but that does generate more heat in the motor and, will either reduce the lifetime of your fan or you have to run it at a lower RPM in order to not reduce the lifetime of the fan. One other feature I wanted to mention. There's a lot of other features depending on the fan that you find, but but one feature I wanted to mention was fan check, which is available on select models for EBM PAPs fans. And what it does is it calculates the statistical service life of any given fan. So if you have a large data center, and you have lots of fans, thousands of thousands of fans like Steve was saying, and you wanna make sure that, understand the life cycle of those, then, FanCheck is a great feature to have. Steve? Okay. Okay. So this this slide nicely shows the EBM PAPs fan portfolio, for data centers. You'll note the highlighted RDHX column, second one in from the left, which emphasizes several different fans, many of which we're going to review in more detail in the next few minutes. The reason I like to show this, portfolio slide is because it nicely demonstrates the many solutions EVM offers for all data center cooling needs. We will start with our most popular fan, for this market segment. We call it Axie ECO 200. Axie ECO 200 was specifically designed for rear door heat exchanger market, as well as in row cooling sidecars and, cooling distribution units, otherwise known as CDUs. A few, highlights in the motor, high speed, low vibration, three phase. You'll note on the image on the left left some of the holes on the hub of the fan. Those are designed to aid in cooling of both the, the motor itself as well as the bearing system. Looking further into the Axio 200, you'll note the fan has both PWM speed control, moisture protection. Vineet just talked about fan check, which is a diagnostic tool, as Vineet said, for predicting service life as well as alarm and temperature sensor functions as well. There's also a nice visual on the right hand side of, the fan's motor PCB. And on to the meat and potatoes slide for the Axie 200, Axie ECO 200, the PQ curve. As you can see, it has a shutoff pressure of just over five inches of water and a free air delivery of close to 1,100 CFM. As you can see, the knee of the curve is just below four inches of water, so overall an impressive PQ curve. This curve shown here is for the 48 volt solution, but the Axi Eco 200 is also available in 24 volts. Standard operating, temperature range for this fan is minus 20 to plus 60 degrees, centigrade. But this can be adjusted if necessary by using different, grease for the bearing systems. This is something we do often for different customers. Just out of curiosity, if you're wondering how how bulky this thing is, it weighs just over three pounds. Now a nice exploded, view of the Axie Echo 200, which shows some of the engineering magic, specifically an enclosed wall ring which rotates with the impeller as one. What this does is it eliminates blade tip turbulence, which helps to reduce reduce overall noise and improve what is known as perceived tonality. This results in a smoother sound to the human ear. As you can see here on the mechanicals, the size of this fan is it's 200 millimeters in diameter, 70 millimeters thick. And now, we move on to AXI ECO's big brother, which is the 2,200 series line. I use the term big brother because the 2,200 F series has been a workhorse fan in multiple industries and applications for over a decade decade right now, whereas the AXI ECO 200 is a relatively newer product to the EDM EBM, fan portfolio. Like its big brother, the 2,200 f series has been successfully deployed in multiple applications, which include in row cooling, CDUs, fan grids, and, of course, rear door heat exchangers. 2,200 f has a shutoff pressure of just under five inches of water and a max free flow delivery of just over 700 CFM. Also, like its big brother, the 2,200 f is available in both twenty four and forty eight volts. And a note on service life, for both of these fans, the 2,200 f and the AXI Eco 200, They have service lights... L 10 service lights that exceed fifteen years at elevated temperature, specifically, at 40 degrees centigrade. Okay. Moving on to the the the less common, but they're they're definitely worth mention mentioning because there sometimes are applications for them, which are the radio blower solutions. These can also be used in here radio or heater changer applications, although they're used to a much lesser, degree because of the difficulties with flow flow geometries. Deneet spoke about that earlier, but that is absolutely the case. Most common frame sizes for these radio blowers that would fit within this market segment would be 190 millimeter to 225. These radio solutions offer max airflow range from anywhere from 530 to 650 CFM, which shut up pressures just short of four to five inches of water. All three sizes shown here are available in twenty four and forty eight volts. Radical two this is the newer, version of the radio solutions with a newer impeller. This particular impeller was designed to improve acoustics. RetiCal two comes in frame sizes of anywhere from 175 millimeters all the way up to 280. You'll also notice a feature here we call flow grid, which is shown in the picture. Flow grid is designed to help, minimize noise, and we've been using this in multiple markets with multiple fans. We already have flow grids made for many, many different, fan series in our portfolio. So if it's something you'd be interested in, we're more than happy to sample it. You can test it. And a lot of people have had very pleasant... Pleasantly surprising results. And last but not least, we're going to go to the w three g 300 series. This would be what I would consider an, per use in a niche application where very high airflow is needed. This series comes in frame sizes anywhere from three to 400 millimeter, and it's offered in 12, 24, and 48 volts. Back to the, portfolio slide. This is worth talking about again. I just want to reemphasize that when I showed you that image of the inside look at the data center earlier, every single one of those market segment boxes can be serviced by any of these different fan families. And, our discussion today was on RDX, and I'm hoping that, you found this both informative and helpful. Moving forward, both SEGGER and EBM PAPS would be happy to work with you on any rear door, heat exchanger and data center cooling needs that you may have. Thank you again for your time and participating in Therm Alive, and with that, I'm going to send it back to Vineet. Yeah, thank you, everyone. Like Steve said, this last, we'll open it up for questions soon. If you scan this QR code, it does take you to the SEGA website on the EBM PAPs product pages. We're gonna do some Q and A now with myself and, application engineer from EBM Papst. Thank you very much. Thanks, Vineet and Steven, for that presentation. Now I'd like to welcome Vineet as well as Steven's colleague Chris Clef Siegel from EBM Papst to answer your questions. Hey Vineet. Hello. Hello. Hi, Chris. Hi. How you doing? Doing well. Are you guys ready to tackle the questions? Yeah. Definitely. Okay. Hey. I will. put them on put them on the screen. Let's see. First one, let's put this up. Why is the housing material metal? I'm assuming that means on the 2,200 f series, housing material is metal likely due to, rigid, making sure that the housing's rigid enough for the application. If you're looking, for more specifics, you can feel free to contact us, later if there's a specific product line you wanna look into. Great. K. Let's move on to the next one. Is noise a concern for RDHX applications? What about data center noise management generally? Not normally with rear to rear heat exchangers, but if it is, let us know what your, sound requirements are for the project, and we can work to make sure we select the right fan for you. Excuse me. We may need to look into other fans that were not presented earlier, like our DIAforce fan, which is, designed for, higher pressure situations while trying to maintain lower noise. Yeah. Just because we had a chance to talk about the presentation that we did at thermal live last year, Curtis, which was the... About the EBM PAP's Diaforce. Yeah. And, I was, a big fan of that one. when... Sorry. I had to say it. Okay. Good. Yeah. So that that one, you know, we talked extensively about tonality. And the application there was more for edge servers, the servers that are located closer to where people are living and working. And, well, not that data centers aren't located close to where people are living anywhere, but, you know, right in the building, for example. And for that, the power tends to be lower, and also noise is more acute of a concern. Whereas for when we're talking about these large data centers and rear door heat exchangers, they're pretty loud. You have lots and lots of fans in them, so, not really a concern for that type of application. Great. I'm going to move on, and here's the next question. What's technology, adopt... Which, what's technology adopted for lower noise in Radical two? Specifically, it's the design of the impeller. It was modified to allow for a more smooth distribution of air through the impeller, so you didn't have any turbulences going through it, which could cause increased noise. So it's really just the, design of the impeller that allowed it to decrease the noise. Okay. Makes sense. Next question asks, having fans in series can be tricky. How do you handle server fans and rear door heat exchanger fans together? Reviewing the standard PQ curves, will be a great start, but, traditionally, you'd wanna look into doing a CFD simulation, as well as testing of the unit to ensure that it is operating the way that you intended. EBM paths, we can do both. We have a team of aerodynamic engineers that can run through CFD simulations for you, and we also have a lab capable of testing, both sound and air performance of your unit. Great. Okay. Here is a temperature question. Do you have motors that can run over, minus 40 to 85 Celsius temperature range? I would have to look specifically to see if we have any products that cover that large range. It... As Steve had mentioned in the presentation earlier that it really depends on the bearing grease that's used. So we would just need to see if there's any existing product that currently uses the correct grease type for that. And if not, what we can do to get, to your temperature range, if not as close as possible to it. Great. Y'all answer it. Y'all are asking some good questions, so, keep it up. It's not too late to... wanted one more thing on the temperature. there, which is, you know, higher temperatures, I mean, fans can always work in the higher temperatures. The question is, what does it do for... To the lifetime? Right, Chris? Like, at 85 c, the bearings are gonna start wearing down pretty quickly, and I don't think, most companies and definitely not EBM paths that prides themselves on good quality and and fans that'll last a long time. They're probably not gonna wanna rate a lot of fans at 85 c because it's just the life cycle would be pretty low. But if you have a type of application where you care about temperature and you don't care as much about life cycle, then you can likely use a fan rated for a lower temperature and, you know, and and get away with it. The other thing is usually if you're talking about 85 c, my guess... I could be wrong, but my guess is you're thinking about it as an outdoor type application, in which case you're also thinking about it being IP rated. So if you have... Now if you have an IP 68 rated fan, encapsulated motor running at 85 c, oh, boy. Your bearings are gonna wear out really fast. So that's where, you know, yeah, it's... This gets nuanced when you really wanna think about the application. Sure. Yeah. As long as you provide us with all all the detailed information about your application, we can review and test as needed to ensure it's the right fan for what your needs are. Great. Next question says, do radial blowers evenly distribute flow in every direction or is there a flow favored side? It is evenly distributed, across... All around the fan. Great. Next question asks, is is a fan still relevant in 2026? Why are we not highly lean towards liquid cooling? Good question. Yeah. I mean, I I think we answered that a little bit in the beginning of the presentation, which is that, yeah, a lot of stuff is moving to liquid cooling, but not everybody is ready to completely jump jump ship and go straight to liquid cooling for everything. It... It's a whole other setup. Right? But the second thing is even for, let's say, a liquid cooled setup where you don't have a rear door heat exchanger, you still have non, like, power hungry components. You still have your memory and, like, your Ethernet chip or whatever that needs a little bit of airflow. So, there's not a lot of, like... Unless you're talking immersion cooling, you're not talking about anything that's, like, completely liquid cooled. Usually, there's some fans in there. So, thankfully for us, yes, fans are still relevant and will be for a long time. Yeah. I'll be using fans for a while, although other technologies out there, it's just, you know, adoption period and whatever. There's plenty of applications for fans. This question says, please give the example and working principle in liquid cooling technologies and electronic for thermal management. Who wants to tackle that. one? I mean, yeah, I mean, I think if you wanna maybe specify that, the person who asked the question, I can... We can answer a more specific one, but I think, generally, when we're talking about liquid cooling, we mean, like, a pump, a CDU, and you're pumping the liquid into, like, a cold plate that's sitting on a CPU or GPU. Sure. I see, one more question for now that just came in. Like I said, guys, it's not not too late to ask your question. But you guy... Vineet and Chris, you guys are doing an excellent job. So this question says, how does vibration affect fan life? It'll have an effect on the Excuse me. Have an effect on the bearing life specifically, as well as the structural integrity of the blades could be in question depending on what your airflow situation is. So it will be good to make sure that, you do the thorough testing needed to prevent any of those issues. Yeah. And this is where, Chris, you know, as you were talking about, like, hey. We wanna know everything about your application. Right? Because if someone says, I need a long life fan. Well, someone might think, okay. Well, let's see. We could switch your bearings to, like, a ceramic bearing. That'll give you a longer life. Oh, you have vibration? Oh, this is a horrible idea. The ceramic bearings are gonna break. Like, if you didn't tell us about the vibration. Right? So if you have external vibration, then that's a different way of looking at the fan than if you're have a hot environment or something like that. Yeah. Makes sense. Well, guys, what, what do you want to leave us with today? If if you asked a question or if we answered your question, we'll make sure, regardless, those questions get sent along to Vineet and Chris and Steven. But, yeah, Vineet and Chris, what what are your parting words? What do you wanna leave us with today? Chris, go ahead. All yours. Well, we... Here at EBM Paths, we have a great team of engineers that are dedicated to looking into all of your application needs. So anything big or small, complicated or simple, we are prepared to assist you in anything for your application. And I'll just say I do air cooling and liquid cooling and interface materials, so give me a call for any of those. Fantastic. Well, thanks, guys. That's gonna do it for the session. Thank you to Vineet and Steven and Chris. Thank you. Thank you. I think this was a great way to get Thermolive started today, and we will be back at the top of the hour at 11AM eastern for our next presentation. So see you in about twenty minutes. Thanks.