There are quite a few self contained rack suppliers with various solutions from direct expansion solutions to central chilled water solutions.
While these solutions can be very good if used in the right situation they can be expensive and have a short life if used in the incorrect application.
I have nicked named these solutions as a box in a fridge.
They are very suitable for small server rooms where you only have one or two racks, but far to expensive, not efficient (environmentally) and difficult to install & maintain/manage for medium to larger data rooms.
You need to be very careful the load (kw & number of servers) do not out strip the capacity of the fridge in a box. If this happens you do not have natural convection in the surrounding areas to assist and you cant just blow the surrounding air into the rack as a temporary solution.
One of the unseen problems that I have found occurring on a regular basis is that either the door to the box in a fridge is left open to long or just forgotten
• Fixing of servers and re-cabling can be an issue as the door needs to be opened.
• Computer techs are the hardest to train and constantly leave the door open ( I just walked away for 5 minutes to get something or why cant I leave the door open to temporally run a cable to another Rack. It’s to hard to run the cable though the correct sealed space that prevents the cold air being lost.
• Threat of death helps
These units generally do not cater for redundancy if a cooling system fails and they do not cater for maintenance as the cooling units do need to be shut down for service. If you turn your IT systems off they may be suitable.
Maintenance cost is also a very important consideration. If you have over a few units it becomes very expansive compared to a central system (some Box in a fridge and chilled water from a central system)
If you just want a couple of racks in a server room they are can certainly be a good solution if redundant cooling is not required.
If redundant cooling is required duel 100% (N+1) traditional cooling is more suitable and don’t overload the racks (an additional rack is not really all that expensive compared to failure & down time.
If you are using 5 or more racks it is better to use the hot/cold isle solutions from either Liebert or APC or similar as these are more flexible, reliable, can have redundancy and cheaper in the long run.
You should also consider the central plant type direct chilled water/fluid cooling options as these are up to 4000times more effective on removing heat, less energy losses with Air to air heat exchange and can handle higher KW per rack. These are more energy efficient and these systems are certainly becoming more freely available and better placed for the future.
In summary it horses for courses and their is not one solution that fits all facilities, user requirements and cost.
Please feel free to contact me if any one wants a non supplier opinion.