News Flash: computers – server computers especially – don't like heat. It's no surprise that if you've ever seen a rack server with its service lid removed, there is a phalanx of fans positioned to cool the system components.
Now you're probably wondering how to cool a server rack. Here are some relatively simple tips & tricks to keep your server cool – especially if you run it in a home or small office environment where a climate-controlled network room isn't an option. We'll also provide some formulas and server maintenance resources if you want to figure out exactly what your server's heat output is (or any appliance for that matter).
But what exactly should the room temperature be?
Most Technology and Environmental experts will tell you that the server room's optimal temperature is between 70 and 81, and relative humidity should be between 45 and 50%. Humidity can be an over-looked factor – too much can lead to condensation on equipment (this could be a consideration for end-users who plan to run their server out of a basement); too little and there is a risk of static electricity shorting out equipment.
Remember, servers can run well outside of these recommended parameters – this is for achieving the optimum performance and life out of your device.
How Much Heat, Exactly, does a Server Give Off?
If you've ever bought an air conditioner, you've probably heard of the energy measurement unit, BTUs (British Thermal Unit). Technically speaking, it measures how much energy is needed to increase a pound of water's temperature by a single degree Fahrenheit while at sea level. When you calculate BTUs on a server, you are determining how much energy the device emits to heat the space.
There are some handy calculators online here if you want to drill down decimal-wise, but the basic formula to calculate the BTU's is to take the total watts and multiply by 3.41.
There are several options to calculate the watts of your server. Often, server manufacturers will list the wattage parameters in the spec sheet – this will give you a ballpark idea. You can also utilize an online power supply calculator – such as the one here. The catch is you need to know all of your server's components for the tool to calculate an accurate number. Lastly, you can make a high-end estimate from the maximum wattage from your PSU (Power Supply Unit). For example, if you have one 750W PSU, the server's max wattage will be 750W. Multiply that by 3.41, and you have an estimate of the server's max BTU (750 x 3.14 = 2,355 BTUs).
For context, a small space heater usually runs about 6,000 BTUs, and a human gives off approximately 400 BTUs. 2,355 BTU's may seem like a high number – but keep in mind, this is calculated with the server running on absolute max.
NOTE: If you have any other networking equipment in the room, e.g., UPS units, switches, etc., you'll want to include their wattage in the total BTU calculation.
Some Simple Tricks if You Notice Your Server is Running Hot
Limit Excessive Light - Add shades for windows to minimize natural light and turn off lights when the room is un-used. Light – especially sunlight – is a significant contributor to adding heat to a room.
Airflow, Airflow, Airflow - There is a reason computers come with multiple internal fans – moving the hot air is half the battle. Make sure your device placement is allowing for proper airflow. You can always check this by measuring the temperature immediately around the server and comparing it to the room's general ambient temperature. If it is significantly higher near the server, you may want to reconsider the placement.
Remember, Heat Rises – If you happen to have hung ceiling tiles above your server, remove them! Heat rises, and the more space that hot air is given to move upward, the less it interacts with your server. The same principle applies to rooms with high ceilings.
Server Maintenance and Environment – Dust is a major enemy of electronics, especially when it comes to heat. Dust collection in the equipment reduces airflow, and dust on the on fans makes them less efficient. We'll cover server cleaning on another blog post in this series, but for now, make sure your server lives in a clean, dust-free (as possible) environment.
Final Thoughts
The short answer: for a single server – rack or tower – most likely, you don't need to make any significant environmental changes to the space. That said, like so many things in life, it can depend. The server's usage and what other network equipment you are using can be impacting factors, as well as the environment of the space you keep it in.
Remember, if you ever have any questions on your planned configuration, reach out to us at TechMikeNY – our Tech's live for this stuff!