Refrigerant Properties Overview
Basic properties of common refrigerants and their significance in HVAC systems.
Refrigerants are the working fluids in air conditioning and refrigeration systems, undergoing phase changes (liquid to gas and back) to absorb and release heat. Their thermodynamic and physical properties are critical for system design, performance, and environmental impact.
Key properties include boiling point (determines operating pressures), critical temperature and pressure (limits of operation), latent heat of vaporization (heat absorbed/released during phase change), specific heat, density, and viscosity. Environmental properties like Ozone Depletion Potential (ODP) and Global Warming Potential (GWP) are also vital due to regulations.
Common Refrigerants and Selected Properties
This table shows illustrative properties. Values can vary slightly by source and specific conditions. Always consult manufacturer data sheets and pressure-temperature (P-T) charts for design and service.
| Refrigerant | ASHRAE # | Type | Boiling Pt (°F at 1 atm) | ODP | GWP (100yr, AR5) |
|---|---|---|---|---|---|
| R-410A | R-410A | HFC Blend | -61.5 | 0 | 2088 |
| R-134a | R-134a | HFC | -14.9 | 0 | 1430 |
| R-22 (Phasing Out) | R-22 | HCFC | -41.4 | 0.055 | 1810 |
| R-32 | R-32 | HFC (A2L) | -61.5 | 0 | 675 |
| R-454B (Opteon XL41) | R-454B | HFO Blend (A2L) | -57.5 | 0 | 466 |
| R-717 (Ammonia) | R-717 | Natural (B2L) | -28.0 | 0 | 0 |
| R-290 (Propane) | R-290 | Natural (A3) | -43.7 | 0 | ~3 |
Notes: HFC = Hydrofluorocarbon, HCFC = Hydrochlorofluorocarbon, HFO = Hydrofluoroolefin. A2L and A3 refer to flammability classifications. The refrigerant landscape is evolving due to regulations phasing down high-GWP refrigerants.