Refrigerant R134a and refrigerant R22 in use has the following difference and features:
1, R134a in the thermal conductivity than that of R22 fell by 10%, so R134a of the unit heat exchanger heat transfer area need to be more big.
2, R134a HFCs refrigerant and its special lipid oil prices are higher than that of R22, the operation of the equipment maintenance cost is higher.
3, R134A has a strong water imbibition, 20 times that of R22, so greater demands of the dryer in the unit system, to avoid ice blocking phenomenon.
4, R134A has a global warming QianNengZhi (GWP) is 0.25, R22 0.36, both belong to the greenhouse gases.
5, R134a of ozone-depleting QianNengZhi (ODP) is 0, R22 is 0.06, this is the reason for R134a become environmentally friendly refrigerant of yantai.
6, R134A has a specific volume is 1.47 times that of R22 and latent heat of evaporation is small, so R134a refrigerating capacity of the unit is only 60% of R22 cryogenic refrigeration unit. Calculated on unit refrigerating capacity price, the price of R22 unit about R134a about 60% of the unit.
7, R134a is larger than that of R22 in rubber material swelling effect is stronger, in actual operation and mid-cooling medium leakage rate is higher. In addition to copper corrosion resistance is stronger, in use process will happen "copper plating phenomenon", so must add additive in the system.
8, R134a system requires a dedicated compressor and special lipid lubricating oil, lipid lubricating oil with high water absorbability, high foaming ability and high diffusivity, on the stability of the system performance inferior to R22 system used in the mineral oil.
To sum up, in the short term there is no ideal refrigerant, refrigerant R22 at this stage in our country compared with R134A has a kind of environmental protection refrigerants, still possesses the advantages of high efficiency, stability, cheap, in the aspect of the application of large refrigeration unit will also be in a dominant position, but before that, will continue to be used as refrigerant R22.
