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EN/06.2018/G42 © STULZ GmbH – all rights reserved
cybercool 2 scroll original insTrUcTions
Refrigerant circuit
The chiller contains two separated refrigerant circuits which are identically composed. Both refrigerant cir-
cuits can be individually operated, which offers the possibility of a capacity grading and which increases the
reliability. The operating hours record of the compressors enables equal utilization of both refrigerant circuits
by sequencing.
An electronic expansion valve is also part of the standard equipment as a filter dryer with replaceable car-
tridge and a sight glass with humidity indication.
Each refrigerant circuit disposes of the following safety devices:
- low pressure switch
- high pressure limiter with reset button
- safety valve
Versions
The standard version for water chillers with scroll compressors has a unit designation, which takes the follow-
ing pattern: CSO _ _ _ _ ASN. There are two more versions which can be combined among each other in
any way.
1. Free cooling version CSO/CQO _ _ _ _ AS
F
This version additionally contains a free cooling coil for each refrigerant circuit. The free cooling coils are con-
nected in parallel in the water-side circuit. During free cooling mode, two motor-driven 2-way valves (size 3
and 4: one 3-way valve) direct the water volume flow completely through the free cooling coils, before it flows
through the evaporator. If free cooling is not possible due to a high outside temperature, the water volume flow
is directed to the evaporator via a bypass line parallel to the free cooling coils.
A control valve is installed in the liquid line and ensures in mixed operation to maintain the condensation pres-
sure, independent of the fan speed.
2. Low noise version C
Q
O _ _ _ _ ASN/ASF
In contrast to the standard chillers of the same construction size, these units work with a reduced air flow.
At approximately the same cooling capacity, a reduction of roughly 10% in sound pressure level is achieved
compared to the standard chillers.
Top view:
Component
location of :
circuit 1
circuit 2
The components of the first refrigerant circuit are mainly located on the left side of the chiller, the components
of the second refrigerant circuit mainly on the right side.
