Cooling a Small Server Room

If you are like most small businesses you most likely are running your servers out of a small closet room. This presents a problem for adequately cooling all your servers that you may have crammed in that room. Fortunately for you, I have found the best solution to overcome this dilemma, and it was worked great for over a year for us.  Our server temperatures now stay an almost constant 69 degrees F.

Picture of our small server room closet with portable air conditioner

Here's a rack of servers in our closet room. Notice the servers are positioned directly in front of the doorway.  This is done on purpose to let the servers pull as much air as possible through the doorway. The room temperature air, about 73 degrees F, is normally too warm for the servers to use to cool themselves so you need to mix it with cooler air. This is where a portable air conditioner comes into play that will blow cooler air in front of your servers. You will need a 14,000 BTU unit to adequately cool a small server room like this and you must get a unit with dual hoses. A quick search on Amazon will find you a unit like this which is exactly what you will need:

Whynter 14,000 BTU Dual Hose Portable Air Conditioner with 3M Antimicrobial Filter

The dual hoses are important because you will need to exhaust the hot air from the unit up into your attic or ceiling. I recommend a heat insulated foil tube to direct the hot air upwards. The intake hose will need to pull from an adjacent room for fresh air. You may be tempted to also close the closet door but you shouldn't. There is a certain amount of air flow you need for the servers and you can't achieve that with the door closed.

Also, a little fan behind the servers directing hot air upwards to the ceiling is very helpful. What we have done is to also remove the ceiling panel directly above this fan to help exhaust more of the hot air from behind the servers. It also helps pull cool air through the servers and out the back.

This setup has worked really great for us and has been in place cooling our server room for over a year now with zero problems. I can highly recommend it to anyone needing to cool their small server rooms.