Characteristics Of The Conventional And The New Refrigerants - Mitsubishi Electric CMB-WM108V-AA Service Handbook

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[11] Characteristics of the Conventional and the New Refrigerants

1. Chemical property
As with R22, the new refrigerant (R410A) is low in toxicity and chemically stable nonflammable refrigerant.
The new refrigerant R32 is low in toxicity and slightly flammable refrigerant.
However, because the specific gravity of vapor refrigerant is greater than that of air, leaked refrigerant in a closed room will
accumulate at the bottom of the room and may cause hypoxia.
If exposed to an open flame, refrigerant will generate poisonous gases. Do not perform installation or service work in a con-
fined area.
Because R32 is slightly flammable, do not perform installation or service work in a confined area.
Composition (wt%)
Type of Refrigerant
Chloride
Safety Class
Molecular Weight
Boiling Point (°C/°F)
Steam Pressure
(25°C,MPa/77°F,psi) (gauge)
Saturated Steam Density
3
(25°C,kg/m /77°F,psi)
Flammability
Ozone Depletion Coefficient (ODP)
Global Warming Coefficient (GWP)
Refrigerant Charging Method
Replenishment of Refrigerant
after a Refrigerant Leak
*1 When CFC11 is used as a reference
*2 When CO is used as a reference
2
These GWP values are based on Regulation (EU) No.517/2014 from IPCC 4th edition.
2. Refrigerant composition
R410A is a pseudo-azeotropic HFC blend and can almost be handled the same way as a single refrigerant, such as R22. To
be safe, however, draw out the refrigerant from the cylinder in the liquid phase. If the refrigerant in the gaseous phase is drawn
out, the composition of the remaining refrigerant will change and become unsuitable for use.
If the refrigerant leaks out, it may be replenished. The entire refrigerant does not need to be replaced.
3. Pressure characteristics
The pressure in the system using R32 is 1.6 times as great as that in the system using R22.
Temperature (°C/°F)
-20/-4
0/32
20/68
40/104
60/140
65/149
HWE1708A
New Refrigerant (HFC type)
R32
R32
(100)
Single Refrigerant
Not included
A2L
52.0
-51.7/-61.0
1.690/245
47.4
flammable
*1
0
*2
675
Refrigerant
charging in the liq-
uid state
Available
R32 R410A
MPa/psi MPa/psi
0.30/44 0.30/44
0.71/103 0.70/102
1.37/199 1.34/194
2.38/345 2.31/335
3.83/621 3.73/541
4.28/621 4.17/605
- 13 -
R410A
R32/R125 R32/R125/R134a
(50/50) (23/25/52)
Pseudo-azeotropic Non-azeotropic
Refrigerant Refrigerant
Not included Not included
A1/A1
72.6
-51.4/-60.5 -43.6/-46.4
1.557/226 0.9177/133
64.0
Nonflammable Nonflammable
0
2088
Refrigerant Refrigerant
charging in the liq- charging in the liq-
uid state
Available Available
Pressure (gauge)
R407C
MPa/psi
0.18/26
0.47/68
0.94/136
1.44/209
2.44/354
2.75/399
Conventional
Refrigerant
(HCFC type)
R407C R22
R22
(100)
Single Refrigerant
Included
A1/A1 A1
86.2 86.5
-40.8/-41.4
0.94/136
42.5 44.4
Nonflammable
0 0.055
1774 1810
Refrigerant
charging in the
uid state gaseous state
Available
R22
MPa/psi
0.14/20
0.40/58
0.81/117
1.44/209
2.33/338
2.60/377
GB