Computer Room Temperature

Over the past ten years computers have increased their heat output considerably. Even a cursory glance at a modern server reveals the huge amount of effort that the designers had to go to in order to keep the computer cool. Not only do the processor(s) have massive heat sinks, but the server will also come fully loaded with fans. In extreme cases liquid cooling is necessary.

Hot Computers, Getting Hotter...

The bad news is that things are getting worse, a lot worse. Processor speeds are going up, heat generation is climbing too.

Once complex water cooling systems were strictly the preserve of the supercomputer user. A supercomputer 15 years ago generated sufficient heat to warm the whole building in which it was housed.

Where does the Heat come from in your Computer Room?

You will not be surprised to hear that most heat comes from the computer’s CPU. But, there are other sources. The power supply itself generates heat. The power supply required a fan long before the CPU required it’s own fan.

Anybody who has seen any modern games will know that computer graphics have come a long way. There is unfortunately a price for the increased performance. Modern graphics cards produce prodigious amounts of heat. Few servers are required to produce high performance graphics, so why buy servers with power hungry graphics cards?

Servers are of very little use unless they are networked to their users. Routers and switches produce large amounts of heat, in some case more than the servers. The large Foundry & Cisco switches are extremely powerful computers with heat generation to match.

Whilst the computer room is rarely a pleasant environment in which to work, sometimes it is necessary to carry out essential maintenance. People generate heat albeit in relatively small quantities (relative to the computers anyway).

Leaving the door open of your computer room can allow heat to enter. Generally speaking, people work in temperatures that are higher than your computer room. Therefore, when the computer room door is opened hotter air will move from the outside into the computer room. Whilst opening the door for short periods may not have a significant impact, leaving it permanently open will make the air conditioner’s job substantially harder.

How can I manage my computer room heat?

Few people have the luxury of designing a computer room from scratch. More usually, requirements evolve over time, and so does the computer room. Things may start off simple but they rarely stay that way. Change is often anything but gradual, a new requirement is identified and the computer room changes quickly to accommodate. Often the changes are done in such a rush that there is no time to take into account the environmental requirements of the new servers. So, the old air conditioning unit is expected to cope with a much increased heat load.

Whilst the temperature of your computer room is important, the temperature that really matters is inside the computer case where all of the electrical components reside. It is possible to have a temperature within the operating range of the computers in most of the computer room but still have one or more computers operating outside of their recommended temperature range.

Placement is absolutely critical in ensuring that your computers stay within their operating temperature range. If the hot exhaust from one computer is being used as the intake into another then the air intake temperature will be substantially higher than the ambient temperature of the computer room as a whole. Using server cabinets with air flow fans installed can help in creating the correct air flow for your computers.

Constant monitoring is the only way to stay on top of things. You wouldn’t dream of not having some kind of monitoring on your servers, so why not monitor the computer room environment too? There are plenty of high quality, modestly priced computer room environmental monitoring solutions around. They won’t cost as much as you think and one serious problem avoided may well justify the entire cost.

Having an environmental monitoring system alert you to extreme environmental conditions in your computer room might mean the difference between you catching a situation before it goes critical, and one that causes you downtime.


If you don’t take temperature into account when designing & then re-designing your computer room you will one day walk inside and find it like an oven. This won’t do you much good, and it certainly won’t do the computers any good either.

Categories: Environment Monitors