At present, only R410A and R32 refrigerants are used to replace R22 refrigerants. Today, the characteristics of R22, R410A and R32 refrigerants in CRR intercooler are analyzed.

1. Thermophysical property: R32 refrigerant charge can be reduced, only 0.71 times of R410A. The working pressure of R32 system is higher than that of R410A, but the large increase is not more than 2.6%, which is equivalent to the pressure bearing requirement of R410A system. Meanwhile, the exhaust temperature of R32 system is greatly increased by 35.3 ℃ compared with R410A.

2. Environmental characteristics: ODP values (ozone depleting potential values) are all 0, but the GWP value (global warming potential value) of R32 is moderate. Compared with R22, the CO2 emission reduction ratio can reach 77.6%, while R410A is only 2.5%, which is obviously better than R410A in CO2 emission reduction.

3. Safety: both R32 refrigerant and R410A refrigerant are non-toxic, while R32 is flammable. However, among R32, R290, r161 and r1234yf, R32 has a high lower combustion limit (LFL), and R32 is the least flammable among these refrigerants.

4. Cycle performance: in terms of theoretical cycle performance, the refrigeration capacity of R32 system is 12.6% higher than that of R410A, the power consumption is increased by 8.1%, and the comprehensive energy saving is 4.3%. The experimental results also show that the energy efficiency ratio of R32 refrigeration system is slightly higher than that of R410A.

The following table compares some characteristics of three air conditioning refrigerants:

What are the common refrigerants?