16
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Piping installation
Installer and user reference guide
70
LRYELRNUN5A7Y1
CO₂ Conveni-Pack outdoor unit
4P605460-1 – 2020.08
16.1.6 To select expansion valves for refrigeration
The system controls liquid temperature and liquid pressure. Select the expansion
valves as indicated according to nominal conditions and design pressure.
Nominal conditions
The following nominal conditions are valid for the liquid piping at the outlet of the
outdoor unit. They are based on an ambient temperature of 32°C and an evaporate
temperature of –10°C.
If showcases or blower coils are connected directly
Liquid temperature
23°C
Liquid pressure
6.8 MPaG
Refrigerant condition
Subcooled liquid
If
capacity up
unit is connected between outdoor unit and showcases or blower
coils
Liquid temperature (at outlet of capacity up unit)
3°C
Liquid pressure (at outlet of capacity up unit)
6.8 MPaG
Refrigerant condition (at outlet of capacity up unit)
Subcooled liquid
(optional) If a pressure reduction kit is connected between outdoor unit and
showcases or blower coils
Liquid temperature (at outlet of pressure reduction
kit)
3°C
Liquid pressure (at outlet of pressure reduction kit)
4.8~5.6 MPaG
Refrigerant condition
Subcooled liquid
Design pressure
Make sure all parts comply to the following design pressure:
2
A
C
A
A
B
C
C
1
5
3
4
A
B
B
A
Liquid piping (refrigeration side): 90 bar
B
Gas piping (refrigeration side): depends on design pressure of showcase and blower coil. For example,
60 bar
C
Gas and liquid piping (air conditioning side): 120 bar
1
Capacity up unit (LRNUN5*)
2
Outdoor unit (LRYEN10*)
3
Indoor unit (showcase)
4
Indoor unit (blower coil)
5
Indoor unit (air conditioning)
