If you've spent some time in data centres before you may recognise the black cabinets in these photos. If you haven't you're probably wondering what is so interesting about black cabinets.

These are our super efficient CRAC units down at M1. We’ve finished the plumbing and they are currently being wired ready for commissioning.

There are a total of 16 CRACs in each data hall at M1 to keep all 500 odd racks at an optimal temperature. The CRACs are positioned in the service corridors which run around the perimeter of each hall.

The main CRAC housings (which you can see in these photos) contain an air chamber and a device that works similarly to your car radiator. Cold water is pumped through the device, which in turn cools the air running through it.

The way this system works is pretty incredible. The air is pulled in through the top of the units to pass through the main air chamber and "radiator". Once it is cooled, it goes through the fans under the raised floor and is blown under the data hall and up through vents that sit underneath each of the racks. As the air warms from the hardware in the racks it rises up and in to the hot air contained isles, once it makes it's way here it is taken up through the ceiling and makes it's way back to the top of the CRACs.

The photo below shows the fans that sit underneath each CRAC unit. This was taken a few months ago before the raised floors were installed.