**Refrigerant Gas R407C:
The capacity and pressure of refrigerant R407C are close to those of Freon R22. Therefore, the system design can be adjusted to make the original R22 system suitable for the R407C refrigeration system. Of course, the mineral refrigeration oil in the original system should be replaced with a lubricant (POE oil) that is compatible with HFC-407C.
Compared with the original system, the energy efficiency ratio of the R22 hvacr system is about 5% lower. This is due to the fact that Refrigerant R407C has a temperature drift of up to 6 degrees relative to other refrigerants. Therefore, the R407C system reduces heat transfer in the same standard condenser and evaporator, affecting the system energy efficiency ratio.
Since R407C is a mixed non-azeotropic working medium, R407C must be liquidly filled in order to ensure that the mixed components do not change. If refrigerant leakage occurs in the system of R407C and the performance of the system changes significantly, the remaining R407C in the system cannot be recycled. The remaining R407C refrigerant in the system must be vented and the new R407C refrigerant refilled.
Refrigerant R407c temperature and pressure comparison table
**Green Refrigerant R290 with LOW ODP:
Hydrocarbon R290 (propane), also known as cold coal, is a new type of environmentally friendly refrigerant, mainly used in central air conditioning, heat pump air conditioning, household air conditioning and other small refrigeration equipment. However, due to its flammable and explosive properties, Freon R290 has a limited amount of perfusion and a safety rating of A3.
High-purity grade Refrigerant R290 is used as a temperature-sensitive working fluid; superior grade and primary grade R290 can be used as a refrigerant substitute for R22 and R502, compatible with the original system and lubricating oil, for central air conditioning, heat pump air conditioning, household air conditioning and other small refrigeration equipment. It can also be used for metal oxygen cutting.
As a hydrocarbon refrigerant, R290 has an ODP value of 0 and a GWP value of less than 20, and has outstanding advantages in refrigeration performance compared with R600a and R134a & R404A. R290 meets the current international and domestic environmental protection requirements, and its performance is suitable for large-volume refrigeration equipment. With the liberalization of follow-up policies, there will be broader development prospects.
Temperature and pressure comparison table of Green Refrigerant R290 with LOW ODP
**Refrigerant Gas R717 (Ammonia):
Green Refrigerant R717 (ammonia), ammonia is a medium temperature refrigerant, the chemical formula is NH3, the boiling point temperature is -33.4 ° C, the freezing point is -77.7 ° C, the critical temperature is 133 ° C, and the critical pressure is 11.417 MPa. Pure ammonia has no adverse effect on the lubricating oil, but when there is moisture, it will reduce the lubricating effect of the frozen oil. In the ammonia refrigeration system, copper and copper alloy are not used for the pipeline and the valve parts.
The R717 (ammonia) synthesis process is mature, easy to prepare, low in price, does not destroy the ozone layer, and has no greenhouse effect. The pressure of the ammonia refrigerant in the condenser and the evaporator is moderate (the condensation pressure is generally 0.981 MPa, the evaporation pressure is generally 0.098-0.49 MPa); the refrigeration capacity per unit volume is larger than that of R22; the latent heat of vaporization is large, and the refrigeration and heat release coefficient are high. . Ammonia refrigerants are widely used in large cold storage and supermarket food display cabinets.
The vapor of ammonia is colorless and has a strong irritating odor. Ammonia is highly toxic to humans and can cause frostbite when it splashes onto the skin. When the volume of ammonia vapor in the air reaches 0.5-0.6%, it can cause an explosion. Therefore, the concentration of ammonia in the air in the equipment room must not exceed 0.02mg/L. Ammonia is not easy to burn at normal temperature, but when heated to 350 ° C, it is decomposed into nitrogen and hydrogen. When hydrogen is mixed with oxygen in the air, it will explode.
Temperature and pressure comparison table of R717 (ammonia) refrigerant