Characteristics Of The Conventional And The New Refrigerants - Mitsubishi Electric PUHY-P200 Service Handbook

[12] Characteristics of the Conventional and the New Refrigerants

1. Chemical property
As with R22, the new refrigerant (R410A) is low in toxicity and a chemically stable non-flammable refrigerant.
However, because the specific gravity of steam is greater than that of air, leaked refrigerant in a closed room will
accumulate at the bottom of the room and may cause hypoxia. Also, leaked refrigerant exposed directly to an
open flame will generate noxious gasses. Use the unit in a well-ventilated room.
Composition (wt%)
Type of refrigerant
Chloride
Safety Class
Molecular Weight
Boiling Point
Steam Pressure (25˚C,MPa)(gauge)
Saturated Steam Density (25˚C,kg/m
Flammability
Ozone Depletion Coefficient (ODP)✻1
Global Warming Coefficient (GWP)✻2
Refrigerant charging method
Addition of refrigerant in case of a leak
2. Refrigerant Composition
Because R410A is a simulated azeotropic refrigerant, it can be handled in almost the same manner as a single
refrigerant such as R22. However, if the refrigerant is removed in the vapor phase, the composition of the refriger
ant in the cylinder will somewhat change.
Remove the refrigerant in the liquid phase. Additional refrigerant may be added in case of a refrigerant leak.
3. Pressure Characteristics
The pressure in the units that use R410A is 1.6 times as great as that in the units that use R22.
Pressure (gauge)
Temperature (˚C)
-20
0
20
40
60
65
New Refrigerant
(HFC system)
R410A
R32/R125
(50/50)
Simulated azeotropic
refrigerant
Not contained
A1/A1
72.6
-51.4
1.557
3 ) 64.0
Non-flammable
0
1730
Liquid charging
Possible
✻1: When CFC11 is used as a reference
R410A
MPa
0.30
0.70
1.34
2.31
3.73
4.17
- 16 -
Conventional Refrigerant
R407C
R32/R125/R134a
(23/25/52)
Non-azeotropic Single refrigerant
refrigerant
Not contained
A1/A1
86.2
-43.6
0.9177
42.5
Non-flammable
0
1530
Liquid charging
Possible
✻2: When CO
is used as a reference
2
R407C
MPa
0.18
0.47
0.94
1.44
2.44
2.75
(HCFC system)
R22
R22
(100)
Contained
A1
86.5
-40.8
0.94
44.4
Non-flammable
0.055
1700
Gas charging
Possible
R22
MPa
0.14
0.40
0.81
1.44
2.33
2.60