White Paper

8
Hot-aisle containment
In a hot-aisle containment system, two ITE rows are positioned back-to-back. As illustrated in Figure 7,
the warm air exhausts into a common aisle area that is isolated from the rest of the room by doors
and vertical ducts. The warm exhaust air is directed up to a dropped ceiling plenum and back to the
CRAH.
Figure 7: Hot-aisle containment with dedicated ductwork
A variation of hot-aisle containment uses a
vertical air duct that vents exhaust air from
the rear area of an ITE rack to a dropped
ceiling air plenum. The HP 10K-G2 Series
42U Rack Air Duct Kit (Figure 8) can be
the answer for an individual rack or in
environments where full hot-aisle
containment is not practical from a
maintenance perspective.
Hot-aisle containment eliminates the
mixing of hot and cold air, thus ensuring
that only exhaust air returns to the CRAH.
This allows the air conditioning system to
operate more efficiently than cold-aisle
containment systems.
The disadvantage of hot-aisle contain-
ment, particularly in facilities without
raised flooring, is the lack of cold air
pressurization that helps direct air to the
front of the IT racks.
Basic room requirement:
Dropped ceiling
CRAH
ITE racks
Figure 8: Hot-aisle containment with the HP 10K-G2 Series
42U Rack Air Duct Kit
Air duct
Rack with
rear
extension kit
installed
Ceiling
Grid
Floor
Grid