Focus on Two Sources
Dual circuit system A safe, flexible system
Some critical applications often require safety devices that prevent
discontinuity of operation due to system failure. To allow for such an
eventuality, YORK can offer “Two Source” systems provided with
two totally independent cooling sources. The Two Sources system is very flexible and allows three different
types of systems:
High operational safety The chilled water primary
source of the unit is connected
to a building chiller or to
District Cooling, whereas
the secondary, emergency,
and direct expansion one is
connected to remote air or in-
built water condensers.
Chilled water + direct expansion Two Sources
In an air conditioning system, the main cooling source may be
insufficient to guarantee suitable environmental conditions. This may
be due to an overload of the system, maintenance, possible seasonal
closures or any type of emergency that may arise.
A reduction in the machine cooling capacity can lead to great instability
in the system, reducing the ability to control the system thermo-
hygrometric conditions.
So as to avoid these problems, specific TWO SOURCES (TS) units have
been developed providing a second source of cooling, complete with its
own control valve and totally independent from the primary one.
Direct expansion + chilled water Two Sources
The direct expansion primary
source of the unit is connected
to remote air or in-built
water condensers, whereas
the secondary, emergency,
and water one is connected
to a dedicated chiller, to a
groundwater/aqueduct water
distribution network or to
District Cooling.
Chilled water + chilled water Two Sources
Both sources of the unit are
chilled water coils. The primary
one is normally connected to
a building chiller or to District
Cooling.
The emergency source can
be connected to a dedicated
chiller or a groundwater/
aqueduct water distribution
network.
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