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Hot and Cold Aisle Containment in Data Centers

Feature Hot and Cold Aisle Containment in Data Centers - AnD Cable Management Blog

Data centers are often made up of hot and cold aisles, and the design of the hot / cold aisle data center is far from new. However, the traditional setup causes warm air exhaust from one aisle to flow into the air intake of the next, meaning that the overall efficiency of the data center is impacted. And really, that’s what hot and cool aisle containment is all about.

Hot and Cold Aisle Containment in Data Centers - AnD Cable Management Blog
Balancing hot and cold aisles is more important than ever to running an efficient data center

As rack density increases, especially in edge data centers and hyperscale data centers, the need for efficiency increases. This is also impacted by the fact that there are more green data centers, who may be generating their own energy using solar or other renewable resources. 

How does containment work and how does it impact your data center?

Remote Monitoring and Temperature Control

Of course, before we get to containment itself, it’s a good reminder to revisit physical layer monitoring. To know how effective any containment effort is, it’s necessary to monitor temperatures. This is most often done with temperature indicating panels, three per rack at the top, middle, and bottom, so that intake temperatures can be monitored regularly.

Of course, someone entering the area to manually check temperatures is yet another disruption to airflow, so remote monitoring as a part of physical network security is essential. This allows managers not only to monitor these temperatures, but receive alerts and take action if something goes wrong. 

A150 Remote Physical Layer Network Security Monitoring Elements
The A150 Remote Physical Layer Remote Monitoring system tracks temperature among many other elements that reduce risk and increase efficiency in data centers

But the most important fact for this discussion is to know what temperatures are so that efficiency and the effectiveness of containment can be monitored.

What is Aisle Containment?

Aisle containment is essentially isolating aisles by relative temperature. Essentially it means placing doors at the end of each aisle, and then adding panels, or barriers, from the top of the cabinet upwards. 

The more airtight this containment is, the more efficient cooling can be, and the easier it is to manage airflow. It’s pretty simple, but there are a couple of different approaches, each with its own pros and cons.

Hot vs. Cold Aisle Containment

There are two ways to manage aisle containment: hot and cold aisle containment. And they work exactly the way they sound.

  • Hot Aisle Containment: Hot aisles are contained, leaving the rest of the room at a more comfortable cool aisle temperature. It’s also easier to manage in many cases.
  • Cold Aisle Containment: Cold aisles are isolated or contained, which means the rest of the room stays at the warmer hot aisle temperature. This can also make getting the right amount of airflow tricky due to pressure changes, but managed properly it can deliver the most uniform temperature air to servers.. 

Choosing the right type of aisle containment for your data center depends on your situation, but there are some differences between new data center construction and retrofitting an existing data center.

Retrofitting vs. New Data Center Construction

In the case of a new data center, most of the time hot aisle containment is the method of choice. This is easier to set up in a new data center, as that allows you to start with the type of containment you need, and to set up HVAC systems and sensors to accommodate that. 

This creates an easier environment for technicians to work in when necessary, and is overall a more efficient choice. However, things are different when it comes to existing data centers

Existing data centers are easier to retrofit with cool aisle containment. While there is some additional monitoring, the way cooling systems work simply means this process is simpler in a currently operating system without creating expensive downtime for making moves and changes and installing containment. 

That doesn’t mean that no new data center will be built with cool aisle containment. It simply means that hot aisle containment is a more frequent choice. 

Partial Containment Solutions

When it comes to retrofitting, sometimes full aisle containment in either format is not possible. In those cases, partial containment is a solution. How is this achieved?

Often plastic strips can be used, similar to those you would go through walking into an industrial freezer or even certain restaurant kitchens. These can be hung at the end of aisles and from the tops of servers to the ceiling, just like other containment methods.

While not as effective, partial containment can be easy to retrofit and implement, and in some cases is about 75% as effective as full containment. For existing data centers looking for a quick and inexpensive efficiency solution, partial containment is a viable option. 

But containment is just a part of rack cooling solutions, and there are some new and exciting ones. 

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Optimizing Server Cabinet Rack Space to Maximize Efficiency and Reduce Costs FREE Guide - AnD Cable Products

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  • How Much Rack Space You Could Save
  • How to Optimize for Maximum Efficiency
  • Savings for New and Retrofit Installations
  • Overall Cost and Space Savings Post-Optimization

The Addition of Liquid Cooling

Data center cooling has evolved from older, inefficient systems to more contemporary ones in a relatively short period of time. However, one thing that has been around for a while but is experiencing a boom in denser, modern data centers is liquid cooling. 

Why? Well, in most cases liquid cooling is more efficient than air cooling in data centers, and when the two are used in conjunction, generally the best results can be achieved. The larger data centers get, the more power they consume, the greater the push towards a blended approach to cooling that not only saves power and is better for the environment, but prolongs the life of equipment and saves space as well. 

But even with the addition of liquid cooling, it’s all about efficient use of rack space and the airflow around them. 

It’s All About Airflow

No matter what kind of aisle containment is used, and no matter how efficient the cooling system, saving space, improving efficiency, and keeping things organized, maximizing rack space efficiency and airflow is vital.

That’s why data centers choose ZeroU racks and cable management systems. They not only help avoid the spaghetti mess and all the cable issues that can arise from it, but also help maximize airflow and save significant rack space in any system.

Whether you are retrofitting a data center or engaged in new construction, we have the rack system that’s right for you. 

Contact AnD Cable Products today for all of your cable, rack, and physical network security needs. We’d love to start a conversation about the right solution for you. 

About the Author

Louis Chompff - Founder, AnD Cable Products, Rack and Cable ManagementLouis Chompff – Founder & Managing Director, AnD Cable Products
Louis established AnD Cable Products – Intelligently Designed Cable Management in 1989. Prior to this he enjoyed a 20+ year career with a leading global telecommunications company in a variety of senior data management positions. Louis is an enthusiastic inventor who designed, patented and brought to market his innovative Zero U cable management racks and Unitag cable labels, both of which have become industry-leading network cable management products. AnD Cable Products only offer products that are intelligently designed, increase efficiency, are durable and reliable, re-usable, easy to use or reduce equipment costs. He is the principal author of the Cable Management Blog, where you can find network cable management ideas, server rack cabling techniques and rack space saving tips, data center trends, latest innovations and more.
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1 thought on “Hot and Cold Aisle Containment in Data Centers

  1. Very informative read, Louis! A hot or cold aisle containment arrangement is a configuration for server racks or other IT equipment in a data center. The purpose of cold or hot aisle containment is to provide more efficient cooling, resulting in lower energy consumption and cooling costs through airflow management. A hot or cold aisle containment design incorporates alternating rows of server racks. To prevent cold and hot air from mingling, cold air intakes are on one side, and hot air exhausts are on the other.

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