Troubleshooting
SiBE811001EB
327
CONVENI-PACK
9.2
Precautions for Electronic Expansion Valve Selection
This model has a larger degree of subcooling (subcooling ratio = condensing temperature - liquid refrigerant
temperature) for the liquid refrigerant of a refrigerator than that of refrigerators without a subcooling mechanism as it
cools the liquid refrigerant with a plate type heat exchanger. The electronic expansion valves feature adjustable
capacity depending on the subcooling ratio for the liquid refrigerant.
When selecting a thermal expansion valve for the load, select one based on the selection method by expansion
manufacturers after checking the subcooling ratio for the liquid refrigerant in the following table.
(A correction value may be added to the electronic expansion valve capability depending on the subcooling ratio.)
Calculated example: The subcooling ratio with evaporative temperature at -10°C and condensing temperature at
45°C becoming 19K (liquid refrigerant temperature at 26°C).
The liquid temperature in the booster unit is further decreased.
The liquid temperature of the refrigeration showcase inlet is approxi10 degrees of the target evaporating
temperature of the outdoor unit.
Subcooling ratio (K) (subcooling ratio = condensing temperature - liquid refrigerant temperature)
Evaporative temperature
-45°C -40°C -35°C -30°C -25°C -20°C -15°C -10°C
-5°C
0°C
5°C
10°C
Condensing temperature
20°C
31K
28K
26K
23K
20K
18K
15K
13K
11K
9K
6K
4K
25°C
31K
29K
26K
24K
21K
19K
16K
14K
12K
10K
8K
6K
30°C
32K
29K
27K
24K
22K
19K
17K
15K
13K
11K
9K
7K
35°C
32K
30K
27K
25K
23K
20K
18K
16K
14K
12K
10K
9K
40°C
32K
30K
28K
26K
23K
21K
19K
17K
16K
14K
13K
10K
45°C
33K
31K
29K
26K
24K
22K
21K
19K
17K
15K
14K
12K
50°C
34K
31K
29K
27K
25K
24K
22K
20K
18K
17K
15K
14K
55°C
34K
32K
30K
28K
27K
25K
23K
22K
20K
18K
17K
16K