R290 Refrigerant is a natural refrigerant.
Nowadays, people are paying more and more attention to the environment protection, and the refrigeration industry is no exception. Refrigerant gases have become a concern for the air conditioning and refrigeration industry because of their impact on the environment and climate change. In Europe, all newly installed plug-in refrigerated cabinets in supermarkets are cooled with natural refrigerant propane.
What is R290 Refrigerant?
R290 refrigerant gas, commonly known as propane, is a natural refrigerant. It used for low-to-medium temperature refrigeration and air conditioning applications in both commercial and domestic systems. It has no harmful to the ozone layer. Now R290 propane refrigerant is used as a low global warming potential(GWP) replacement for refrigerants R22, R404A & R134A and many other refrigerants.
What’s The R290 Refrigerant Properties?
The R290 refrigerant gas, is also called propane. It has long been known for its good refrigerating performance, excellent environmental and thermos-physical properties. However, it is a highly flammable refrigerant. Due to its flammable and explosive properties, the R290 charge is limited and the safety group is A3. Please find R290 properties table below.
| Formula | C3H8 |
| Molecular weight (g/mol) | 44.1 |
| Boiling temperature °F (°C) | -42°C |
| Critical temperature | 96.7°C |
| Latent heat (-10°C) | 375 kJ/kg |
| Density saturated liquid (-10°C) | 542 kg/m³ |
| Volume capacity (-10°C) | 1846 kg/m³ |
| COP (-10+45°C) | 3.7 |
| GWP | 3 |
| Class | A3 |
| Lower flammability limit | 0.038 kg/m³ |
| Combustion heat | 2200 kJ/mol |
| Auto-ignition temperature | 470°C |
| Practical limit | 8 gr/m³ |
From the perspective of environmental protection and performance, it is a perfect solution of R290 refrigerant replacement of R134A and R404A. But the R290 refrigerant biggest problems are the flammability and explosion, which requires increased safety measures during use.
Compared with R32, the flammability of R32 refrigerant is A2, it is mildly flammable refrigerant, while the flammability of R290 is A3, which is a highly flammable refrigerant. So many people will be afraid that R290 is dangerous. Please see the flammability comparison below of R22 vs. R410A vs. R32 vs. R290.
| Type | Class |
| R22 | Non-flammable |
| R410A | Non-flammable |
| R32 | Mildly flammable |
| R290 | Highly flammable |
Precautions
- It is strictly prohibited to install without vacuuming: If there is no vacuuming, there will be air and oxygen in the refrigeration system. It is strictly prohibited. It must be evacuated (to avoid leakage or air entering the system) after the pipeline connection and pressure maintenance and circuit work are completed.
- It is strictly forbidden to shorten the vacuuming time to prevent the system from containing air. The vacuuming time should not less than 1 hour.
- Smoking is strictly prohibited during installation and maintenance, and fire or heat sources are strictly prohibited in the operating area.
- It is strictly forbidden to purchase low-quality refrigerants. Using low-quality refrigerants may increase the possibility of combustion and explosion in systems.
- It is strictly prohibited to weld if there is refrigerant in the system.
- It is strictly forbidden to use an open flame to heat the refrigerant tank and fill it with refrigerant.
