Check The Difference Between R410A, R134a, R407C and R22
Currently, the common refrigerant types for the air conditioner are R410A, R134a, R407C, and R22 (The flammable and explosive refrigerants like R32 will be introduced separately later).
Now, we briefly analyze the use and differences.
R134a and R410A
- R134a is a single component refrigerant, while R407C and R410A are mixed refrigerants;
- R410A is a mixture of R32 and R125, and R407C is a mixture of R32, R125, and R134a;
The mixed refrigerant advantage is, considering various properties such as flammability, capacity, discharge temperature, and efficiency, which be mixed into another refrigerant according to the specific user requirement.
R134a and R22
- The capacity of R134a is smaller than that of R22, and the pressure is lower than that of R22. Due to these features, an R134a air conditioner with the same capacity must be equipped with a larger compressor with a larger evaporator, condenser, and piping. The result is that the R134a system will cost more to manufacture and operate a system with the same cooling capacity as the R22.
- The water absorption of R134a is very strong, which is 20 times that of R22, so the requirements for the dryer in the unit system are higher to avoid ice blockage.
- R134a system needs a special compressor and special grease lubricating oil. Because of its high water absorption, foaming, and diffusivity, grease lubricating oil is inferior to the mineral used in the R22 system in terms of system performance stability.
R407C and R22
- The capacity and pressure of R407C refrigerant are close to R22. Therefore, the original R22 system can also be applied to the R407C system by adjusting the system design. Of course, the mineral refrigeration oil in the original system should replace with lubricating oil (POE oil) that can be miscible with R407C.
- But the energy efficiency ratio of the R22 system will be reduced by about 5% compared with the original system due to the temperature drift of R407C up to 6 degrees relative to other refrigerants. Therefore, the R407C system will reduce heat transfer when the same standard condenser and evaporator are used, which will affect the energy efficiency ratio of the system.
- Because R407C is a mixed non-azeotropic working fluid, to ensure that its mixed composition does not change, R407C must be charged in a liquid state. Suppose the R407C system leaks refrigerant and the system’s performance changes significantly. In that case, the remaining R407C in the system cannot be recycled and used. The remaining R407C refrigerant must be emptied and recharged with the new R407C refrigerant.
R410A and R22
- The capacity and pressure of R410A refrigerant are higher than that of R22, and the operating pressure is 50%-60% higher. The operating noise of the R410A is significantly lower than that of the R22 compressor by 2-4 decibels.
- Compared with the R22 system, the R410A refrigerant system has a significant heat transfer advantage in that the heat transfer is 35% higher in the evaporator and 5% higher in the condenser. But the system heat transfer coefficients of R134a and R407C are lower than that of R22.
- In the system redesigned for R410A refrigerant, the evaporator and condenser with smaller volumes are used, which will be lower in cost, and the refrigerant charge can be reduced by up to 30%. The reduction in refrigerant charge, in addition to cost reduction, will also improve overall system reliability.
- In a system with the same cooling capacity and condensing temperature, the system energy efficiency ratio (COP) of R410A refrigerant can be 6% higher than that of R22. Due to lower losses in the compressor during compression, greater heat transfer between the evaporator and condenser, and less pressure drop across the system. With efficient heat transfer and smaller pressure drop, which enable lower condensing temperature and higher evaporating temperature under the same operating conditions, the compressor obtains a better Operating range with less power consumption and a higher efficiency ratio.