Cooling Options? Would love some advice here.
 

Hi all, i'm new here and was wondering if I could get some new opinions. I've been researching in row cooling and was wondering if anyone here knew anything about the technology behind it? Obviously APC is most well known for In Row Cooling. What other brands do in row cooling and what are the differences? For what size data centers is In Row Cooling a good solution? What is the cost of In Row Cooling units? What is better in the long term (10 year life cycle) In Row Cooling units or CRAC units?

Thanks in advance.

Hi and welcome to the forums. Most manufacturers of data center cooling equipment now make in-row units. Liebert, Rittal and now Stulz have rack-sized units designed to co-exist with rows of server racks on the data center floor.

When combined with hot or cold air containment, these closed designs are much more efficient than traditional CRAC cooling. This increased efficiency is due to closer coupling of the heat exchange process and better control of the hot and cold air streams. Additional advantages over CRACS are scalability (unit capacities allow finer incremental scale-up or -down), increased density and easier zoning (grouping equipment with similar densities). Small unit capacities allow precise treatment of hot spots as well as the economical addition of redundancy. Read the vendors' web sites for other advantages of in-row technology.

On the down side, this is not cheap technology. Also, it's usually proprietary and does not play well with others. Compared to traditional CRAC units, in-row units have more sophisticated sensor and control systems, more complicated electronics (network interfaces, internal diagnostics, software to coordinate with other units), the same or higher airflow in a much smaller footprint and shorter service intervals -- all of which may lead to decreased availability of individual units.

Overall, the good probably outweighs the bad. But, it's best to know the pros and cons before making a major design or renovation.

Hope that helps.

Ken

Just to add to Ken good advice, In-row & In-Rack systems work best when containment is implemented. This allows the cooling units to operate with a higher Delta T, meaning far higher efficiency than most floor based systems.

The one down side of containment is that you will loose the thermal reserve that a big open space provides. This means that you need to spend more money on redundancy both in IT and cooling.

Just to follow up, because of the lack of "thermal ballast" raid mentions, it is a good idea to seek out DX in-row cooling units that can be dual-wired: fans and controls connected to UPS and compressors, humidifiers and reheats wired to generator only. This way, UPS capacities need not be sized for huge loads. If your vendor doesn't support this, ask them to!


Ken

im not entirely certain and please correct me if i am wrong but isn't modular cooling a better option? i checked some videos on youtube (rittal actually) and they seem more energy efficient..they might be a tad bit on the expensive end but what's a little extra investment if they are cutting down your cooling expenses every month?

Exactly right. Rittal's LCP modular cooling is one example of the in-row cooling we've been discussing. Other companies offer similar products, but all describe them a bit differently.

Ken