The concept of separating the cool supply air and the hot air exhaust return air. When implemented properly, energy saving are possible, cooling capacity may be increased, densities per rack can increase, longer life span of the equipment and more resilient to mechanical system failures. There are three basic kinds of containment
- Hot Aisle containment: Encapsulating the rack hot aisle and returning the exhaust to the CRAC/CRAH with no to minimal mixing with the supply air.
- Cold Aisle containment: Encapsulating the rack cold aisle to ensure the supply air is delivered to the equipment inlets without mixing with the hot air exhaust. Partial containment can be done by simply installing end of row doors with no ceiling.
- Rack based chimney. Racks with solid rear doors and chimney collared to a ceiling plenum or duct work to deliver the hot air exhaust to the CRAC/AH without mixing with the supply air.
Each has many variations and advantages over each, but is far superior than the traditional flooded air approach. Containment costs can be recovered quickly through lower mechanical capital costs and lower operating and maintenance costs.Because of the energy savings, containment can contribute to a lower carbon footprint.