CYBERHANDLER 2 INSTALLATION, OPERATION AND MAINTENANCE MANUAL
EN/05.2019 © STULZ GmbH – all rights reserved
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The pipe diameter must be chosen according to the following diagrams:
Liquid lines
depending on the overall pipe lengths and
refrigeration outputs with a permissible
pressure loss of: 15 kPa
Pressure lines
depending on the overall pipe lengths and
refrigeration outputs with a permissible
pressure loss of: 30 kPa
Further conditions:
tc = 45°C
to = 3°C
Subcooling: 3K
Superheating: 7K
This cooling capacity is at least required for oil transportation in rising pipes of pressure lines at
tc (dew point) 45 °C, to 10 °C and hot gas temperature 70 °C.
R410A
Pipe diameter
mm
15
18
22
28
35
42
Refrig. capacity
kW
1.48
2.47
4.32
7.56
14.04
22,92
The units contain an oil separator which is installed at the hot gas side of the compressor and
serves to recuperate oil in all operating states. The separated oil is injected on the suction side
of the compressor.
For the liquid line we recommend to install a non-return valve near the condenser, this avoids
the return flow of refrigerant in to the condenser and a possible low pressure error at the unit
start.
For the hot gas line we recommend to install a non-return valve as close as possible to the Air
Handling Unit. The non-return valve avoids the return flow of liquid refrigerant from the con-
denser when the AHU is not in operation.
