Direct Free Cooling and Water Cooling: which method to choose for TLC rooms and Data Centres?

 

There are various methods for preventing overheating and keeping technical premises such as data centres and telecommunications rooms cool. The key elements in these processes are air and water.

 

In general, all IT equipment is air-cooled: all parts of the equipment take in air from the environment and expel heat at the exhaust end. Since, for example, a data centre may contain thousands of devices, the result is that there are numerous paths of hot air flows within it, which together account for the total waste heat production of the data centre. Heat that, as we said, must be removed.

 

Let’s take a closer look at the various cooling methods: first of all, it should be noted that many people in the industry do not like the water-cooling solution so much that they oppose its implementation.

The risks of water cooling

The greatest fear is that a server will ‘fry’ due to water infiltration. Water-cooling systems can leak profusely if the design is poorly executed, causing a water disaster in the technical rooms.

 

On the other hand, the possibility of human error is not to be underestimated: statistics on the causes of downtime in a data centre indicate that in 80% of cases it is due to human error. Water is a universal solvent. Given a period of time, it is capable of altering the state of any type of surface, including metal parts.

 

Suffice it to say that fire suppression systems in most technical rooms do not contain water; in many cases the damage caused by this element can be greater than the damage caused by fire.

 

In addition, a water cooling system involves a number of other installations such as pipes, cooling blocks (cold plates) connected to each component to be cooled, a tank, a pump and a filter.

 

It is not difficult to imagine what it means to regularly clean a water-cooling system (which perhaps uses water from a river, and therefore requires specific, complicated and expensive filtration). In addition, the maintenance of such a system is complex as it will be necessary to periodically remove the liquid.

 

Another disadvantage is that very often the design of motherboards, desktops and servers is not adapted to liquid-based systems, but is based on air systems with cooling fans.

 

In short, this is a much more expensive process in many respects than, for example, simply vacuum cleaning the fans.

The use of water in Indirect Free Cooling

In indirect free cooling, cold water is also used to disperse the heat in the technical rooms, channelling it into the AHU (central air handling unit).

 

And even in this solution, one of the disadvantages arises from the fact that, as the room temperature falls, the humidity in the air rises. Condensation can then form on cold surfaces, with the possibility of corrosion and dripping.

 

A scenario that can be avoided by (partially) dehumidifying the air before it is supplied. However, dehumidification requires lower water temperatures than are normally possible. It may therefore also be necessary to switch on the air conditioning or mechanical ventilation. This results in additional costs and higher consumption.

The best solution: Direct Free Cooling

We are talking about the most intelligent and least expensive system for cooling rooms such as telecommunications and data centres. It collects cold air from outside and channels it into the technical rooms, completely free of charge and environmentally friendly.

 

What does Direct Free Cooling consist of and how does it work? You can find out more in this article.

 

In short, outside air with a lower temperature replaces warm indoor air.

 

It is easy to see how this can have a positive effect on the economy. By only using air from outside, there are no additional costs due to the use of systems that consume electricity.

 

In addition to not affecting the environment, compared to a water cooling system, Direct Free Cooling requires extremely low maintenance, and the system itself manages the activity of the heat exchanger according to the outside air temperature.

 

In addition to this, problems with humidity, corrosion and the danger of large leaks or drips are totally eliminated.

 

If you have any questions or would like more information about our services, please contact us!