
Instructions
118A5495A - AN405821998738en-000102 | 57
© Danfoss | Climate Solutions | 2023.02 | LCA012A024
Use condensing unit oils recommended by Danfoss.
Synthetic oil (ester oil) compatible with R744 is used.
Table 1 - Physical properties and saturated vapor pressure of R744
Item
CO
2
(R744)
R410A
Composition
CO
2
R32/R125 (50/50) Pseudo azeotropic refrigerant mixture
Ozone depleting coefficient
0
0
Global warming potential
1
2090
Saturated vapor pressure
(bar, absolute pressure)
-20°C
1.97
0.04
0°C
3.49
0.80
20°C
5.73
1.44
25°C
6.4
1.65
30°C
7.21
1.88
Boiling point (°C)
-78.5
-51.4
Critical temperature (°C)
31.0
71.4
Critical pressure (bar, absolute)
73.8
49.0
Source: NIST Refprop9.0, 4th IPCC Report 2007
Annex E - Outline of refrigerant
Outline of the refrigerant R744
R744 is an environmentally friendly refrigerant with the ozone depleting coefficient at “0” and a smaller global warming potential. Refrigerant R410A is
comparable with this in terms of the ozone depleting coefficient but has a higher global warming potential. R744 has a higher pressure of 64 bar under
ordinary temperature, which is approx. 4 times higher than 16.5 bar of R410A.
Following shows physical properties and saturated vapor pressure of R744. It should be noted that products using R744 refrigerant are not compatible
with those using Freon gas. When installing a product, check the equipment nameplate, or the like, for applicable kind of refrigerant.
Note on R744
Judgment of R744 application products
R744 application products are notified so on their nameplates.
It should be remembered that they are not compatible with products that use Freon gas.
Characteristics of R744 refrigerant
Physical properties and saturated vapor pressure of R744 are as shown in Table 1.