Definition:The temperature above which a gas cannot be liquefied regardless of pressure applied. Each refrigerant has a specific critical temperature.
Why It Matters:: Determines refrigerant selection for specific applications. CO₂ (R744) has a critical temperature of 31.1°C, making it challenging for use in high-ambient South African summers but excellent for cold storage.
Common Refrigerant Critical Temperatures::
- R134a: 101.1°C
- R404A: 72.1°C
- R744 (CO₂): 31.1°C
- Ammonia (R717): 132.3°C
Related Terms:: Refrigerant, Subcooling, Superheat