MackFri® - 10a
MackFri® - 10a
ASHRAE Name : R410a
(50% HFC-32/50% HFC-125)
The Blends for replacement of HCFC's.
MackFri®-10a refrigerant. It is a double azeotrope blend of hydrofluorocarbons R32 and R125 with equal mass proportions of the components (50 and 50 %). Ozone depletion potential ODP = 0. Global warming potential HGWP = 0,45. It serves as a refrigerant alternative to R22, and it is intended for charging of the new air-conditioning systems of high pressure. Specific cold-productivity of MackFri®-10a is approximately 50 % higher than that of R22 (at condensation point 54 oС), and working pressure in the cycle is 35...45 % higher than that of R22, which causes the necessity to introduce structural alterations into the compressor and heat exchangers, and consequently, increase of capital costs. Physical qualities of MackFri®-10a refrigerant are given down.
Since the density of MackFri®-10a is higher than that of R22, compressors, communication lines and heat exchangers should have smaller size.
In the refrigeration systems operating on MackFri®-10a, it is recommended to use polyester oils.
Packing: 11.0 Kg. (25 lb.) Net nonrefillable Steel cylinders and individual neutral carton outside.
- Acceptable Substitutes for Class II (HCFCs) Substances in Air Conditioning and Refrigeration under the Significant New Alternatives Policy (SNAP) Program as of December 18, 2000 as:
 a) replacement for HCFC's in the Household and Light Commercial AC (N)
b) replacement for HCFC's in the Commercial Comfort Air Conditioning (N)
c) replacement for HCFC's in the Industrial Process Refrigeration (N)
d) replacement for HCFC's in the Industrial Process Air Conditioning (N)
f) replacement for HCFC's in the Cold Storage Warehouse Systems (N)
g) replacement for HCFC's in the Ice scating Rinks (N)
i) replacement for HCFC's in the Refrigerated Transport (N)
j) replacement for HCFC's in the Retail Food Refrigeration (N)
k) replacement for HCFC's in the Ice Machines (N)
l) replacement for HCFC's in the Household and other Refrigerated Appliances (N)
(R) = Retrofit Uses
(N) = New Uses
Similar : SUVA 9100, AZ 20, Forane 410a, Solkane 410
Physical properties:
| Parametr |
|
| Molecular mass, gm/mole |
72,58 |
| Boiling point at 1,0325-105 Па, 0C |
-51,58 |
| Freezing point, 0C |
-- |
| Thermal critical point, 0C |
72,1 |
| Critical pressure, 105Pa |
49,2 |
| Critical density, kg/m3 |
488,9 |
| Liquid density at 25 0С, kg/m3 |
1062 |
| Heat of vaporization at boiling point, kilojoule/kg |
264,3 |
| Saturated vapor density at -25 0C, kg/m3 |
18,5 |
| Vapor pressure at 25 0C, 105 Pa |
1,653 |
| Limiting inflammability in the air, % of the volume |
No |
| Self-ignition temperature, 0C |
- |
| Ozone depletion potential ODP |
0 |
| Global warming potential HGPW |
0,45 |
| Global warming potential for 100 years GWP |
1890 |
| Maximum allowable concentration on a working place, ppm |
1000 |
|
 How to work with R410a refrigerating medium?
R410A is meant to be used in new R22 and R13B1 plants. It constitutes of mixed in equal mass portions refrigerating mediums R32 and R125. Neither of forming components contains chlorine, because of this mix is characterized by zero ozone destroying potential (ODP) value. Due to the increased specific cold-productivity, it is possible to reduce the size of main elements of hydraulic contour: heat exchangers, pipelines are possible. In addition R410A is an pseudoazeotropic mix, in other words its temperature during phase transition is virtually stable. Therefore upon leakage ratio of mixture in contour is virtually unchanged, what allows adding the required amount of mixture after leakage without the complete refrigerating medium regeneration. In addition this new refrigerating medium has considerably higher working pressure value. For example at the dew point 43°С R22 has the pressure 15,8 atm, and R410A - nearly 26 atm. Therefore, a simple replacement of R22 with the new refrigerating mediums is impossible and the modernization of equipment demands structural modifications to be made to the hydraulic contour elements in order to increase their strength. The same way as the R407C refrigerating medium, it is not dissoluble in coal oil and presumes the use of synthetic polyester oil.
During installation of the equipment on R410A it is necessary to adhere to the following basic reference, already known by the R407C refrigerating medium:
- do not allow the soiling to get into the hydraulic contour;
- during pipe soldering, the pipes must be filled with inert gas, e.g. nitrogen with low water temper;
- the vacuumization must be done especially carefully;
- topping-up of the refrigerating medium must be done only in liquid phase.
Here are several recommendations on the complete air and moisture vacuumization of the contour. In order to vapor out water into gaseous form without heating, it is necessary to lower the pressure in the contour. The lower the temperature in contour (outdoor air), the less is the pressure of water evaporation. Corresponding data is given in the table. Therefore during vacuumization the residual pressure in contour must be so, that the evaporation temperature for this pressure will be lower than the outdoor air temperature.
| The water evaporation pressure given different air temperatures. |
| Temperature, °С |
Pressure, millibar |
| 5 |
9 |
| 10 |
12 |
| 15 |
17 |
| 20 |
23 |
| 25 |
42 |
|
Special attention should be paid to instrument selection. Vacuum pump can be both single-stage and double-stage, but its output should be no less than 4-8 m3/hr for systems with cold-productivity up to 11 kilowatt and 8-15 m3/hr for more high-powered systems.
Manometric manifold should be appropriate for R410A, it must have the pressure-temperature gauge that corresponds to this specific refrigerating medium and enlarged diameter of ports for flexible hoses connectors (considering the substantial differences of thermodynamic characteristic of R410A and R22, R407C).
Very important! Vacuum measurement with low pressure manometer (up to 17 bar) on manometric manifold is inadmissible, since it does not provide the necessary precision. The special manometer for vacuum measurement is a must, only using this special manometer can the residual pressure be measured and the absence of moisture in contour measured in the approved manner.
If you follow this simple recommendations and use the professional instruments, applying it as it is designated, the installation and after-sales service of the equipment, working on R410A will not cause any trouble. And the users will benefit from the reliability and high energy efficiency of the new conditioning systems.
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