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Operating and Maintenance Instructions – 10 Frequently asked questions (FAQ)
Rittal Liquid Cooling Package Plus
Can the Liquid Cooling
Package be operated when
the doors are opened?
The response of the Liquid Cooling Package upon operation with opened doors
depends chiefly upon the prevailing ambient conditions. If a front door is
opened, the cool air is mixed marginally with the ambient air. Thus, no cooling
problems are expected in air conditioned rooms. Overall, no heat is carried into
the room. The back door should only be opened for a short while during oper-
ation, since this breaks the cooling air circuit, resulting that the waste heat is
carried into the room. However, this does not influence the cooling of the units
in the enclosure.
Why is the Liquid Cooling
Package, as an air/water heat
exchanger, installed on the
side panel?
It was important to develop a high performance cooling system which would
also meet the requirements of the coming years. This could only be achieved
by routing the cooling air in a manner which was tailored to the needs of the
devices. The chief problem encountered when cooling with air from the raised
floor, or with roof or floor heat exchangers is the air flow. Cold air which is fed
into the enclosure from below or above changes its temperature greatly be-
cause of recirculation. Temperature differentials of up to 20 °C were measured
from "below" to "above" in enclosures found in data centres. Thus, a server in-
stalled "below" in an enclosure may have temperature conditions of up to 20 °C
"better" than one installed "above" in an enclosure. Because of this, in order to
achieve sufficient cooling of all systems in the enclosure when using this sort of
cooling, a significantly lower air temperature must be used. When cooling air is
provided from the side, this problem does not arise. Cooling is more effective
and more exact because the air supplied to the units can be held within 1-2 °C.
Because the system is built as its own enclosure, the system is protected
against the risk of leaks. All water-carrying parts are located outside the actual
server enclosure. Connection to the cooling water network is made in the floor.
Further, Rittal has many years of experience in the field of air/water heat ex-
changers. All of this experience is incorporated into the construction of the Liq-
uid Cooling Package. Because of these precautionary measures, even in the
very unlikely event of a leak, water cannot find its way into the area for electronic
components. Because of its "thin" profile of just 300 mm, the pattern achieved
in the data centre is not interrupted. Because the depth of the enclosures is not
increased, the full width of the walkways in the data centre is maintained.
How is water connected to the
Liquid Cooling Package?
For easy installation, connection to the building or recooling system is made, as
desired, from below or from the rear with 1" threaded connections. Of course,
these may be exchanged with quick-release couplings.
Can both air-cooled and water-
cooled server enclosures
operate side-by-side in a data
centre?
Of course. There must only be a water installation available for the water-cooled
enclosures. The advantage of this is that the existing room air conditioning is
not further burdened. Thereby, Liquid Cooling Package Systems can be used
to intercept "hotspots" in the data centre without requiring the expansion of the
air conditioning system.
Which dimensions are usable
for the Liquid Cooling
Package?
The Liquid Cooling Package itself has the dimensions W x H x D 300 x 2000 x
1200 mm. Every Rittal enclosure with the dimensions H x D 2000 x 1200 mm,
independent of width, can be bayed. Other sizes available on request.
Does the Liquid Cooling
Package require
maintenance?
The Liquid Cooling Package is maintenance free. All components are designed
with an extremely long lifespan. In case of a malfunction a message is gener-
ated through the alarm output of the control unit or through the Basic CMC.
What advantages does a
water-cooled solution have
over an air-cooled solution in a
data centre?
The use of water-cooled enclosures allows for controlled, efficient and cost-
saving cooling of heat losses, which was not possible with conventional air con-
ditioning. Thus, it is possible to fully use the space, which is physically available
in the enclosures, instead of being forced to erect half-empty enclosures be-
cause of air conditioning problems. This achieves considerable savings in the
investment and operating costs of a data centre.
