Precautions for using refrigerant r404a

The domestic research and development and use of environmentally friendly refrigerants continue to accelerate the pace, some environmentally friendly refrigerants have gradually appeared in the refrigeration market, R404a refrigerant is an environmentally friendly refrigerant, environmentally friendly refrigerant R404A as a substitute for R22 First, the refrigeration performance of the two is relatively similar, but there are several issues that need to be paid attention to in the replacement process.

The physical characteristics of R404A instead of R22 need to be noted: 1. The problem of using R404A refrigerant to replace R22 refrigerant is the problem of lubricating oil, and it must be matched with PVE ester oil to replace R22 Use mineral lubricants. 2. The exhaust pressure of R404A refrigerant is about 1.2 times that of R22, and the mass flow rate is about 1.5 times that of R22. The exhaust flow rate increases and the resistance increases. Generally speaking, the heat exchange capacity of the condenser is 20% to 30% larger than that of R22. DuPont R404A refrigerant and R22 refrigerant have different saturation pressures at the same temperature, so the operating mechanism of R404A thermal expansion valve is different from that of R22. 3. Since the saturation pressure of the refrigerant R404A is higher than that of R22, the design pressure of the pressure vessel in the system needs to be changed. 4. R404A is a non-azeotropic mixture working fluid. The component concentration of the non-azeotropic mixture changes with temperature and pressure. This brings certain difficulties to the production, debugging and maintenance of the refrigeration system, and also affects the heat transfer performance of the system. In particular, when the refrigerant leaks, the system refrigerant needs to be completely emptied and replaced, so as to ensure the proportion of each mixed component and achieve the designed refrigeration effect, otherwise it will get worse. 5. Because R404A refrigerant and lubricating oil have good compatibility with water, the requirements of the system for moisture, residues, and cleanliness are improved compared with R22 refrigerant. R404A system moisture control and impurity control It is a relatively important indicator, and the corresponding filtering device in the system needs to be changed.

This is the end of the above related introduction of R404A refrigerant, I hope it can bring you some help.