Specifications

3-2
Site Preparation Guide
Air-Conditioning System Specifications
Warning:
If the air-conditioning system is shut down, "operational" conditions must be re-established, in
compliance with temperature and hygrometry gradients, AT LEAST ONE HOUR before
powering up the server.
To optimize the air duct network, air-conditioning cabinet(s) must be installed in the Computer
Room or in an adjacent room. Filters must be easily accessible for regular checks and easy
cleaning.
All materials liable to fragment, disintegrate, or crumble through ageing, handling or when
subjected to conditioned air flows are prohibited. If the use of such materials cannot be
avoided, they must be coated with anti-rust paint. Ventilation ducts must be made of a
non-combustible, non-pulverulent material. Glass or mineral fibers must not be used in the
conditioned air distribution or recycling circuit, unless packed in seal-tight bags.
The effectiveness of air-conditioning unit filters must comply with the "A.S.H.R.A.E" test, >
36% (to be checked with manufacturers).
Air Renewal, Distribution, Circulation, Pollution, and Filtering
Renewal
A fresh air supply is mandatory for the comfort and health of personnel. The fresh air supply
must be directly input at air-conditioning unit level and must be filtered in compliance with
local health authority regulations (D.D.A.S.S. Regulations in France).
The Data Processing Center is over-pressurized via the fresh air supply which must be strictly
limited to 1 - 1.5 times room air per hour. Over-pressurization presents the advantage of
moving air outwards, thereby preventing dust from entering the premises.
Distribution
Bull NovaScale Servers release high levels of heat and require the installation of a high
airflow air-conditioning system.
Delivery of air through the raised floor plenum is the most appropriate solution. The
air-conditioning specialist must define the number and location of the perforated and / or
damper slabs required for correct air distribution.
Advantages:
• absence of constant draughts,
• airflow directed from the bottom up, from cold to hot,
• good air distribution through perforated or damper slabs,
• easy layout changes.
Note:
It is mandatory not to install hardware or furniture on one or more perforated / damper
slabs in the Computer Room.