Which gas is used in AC?

The gases primarily used in air conditioning (AC) units as refrigerants are R-290 (Propane) and R-32 (Difluoromethane). These are favored for their improved environmental performance compared to older refrigerants.

Refrigerants in Air Conditioners Explained

Air conditioners utilize a refrigerant to cool air. The refrigerant cycles through the AC unit, absorbing heat from inside the space and releasing it outside. The refrigerant undergoes phase changes from liquid to gas and back again during this process.

Common Refrigerants

• R-290 (Propane): A natural refrigerant with a low Global Warming Potential (GWP). It's flammable, requiring safety precautions in its use.
• R-32 (Difluoromethane): A synthetic refrigerant with a lower GWP than many older refrigerants like R-22 and R-410A. It's also more energy-efficient.
• R-410A: Previously a very common refrigerant, but it is being phased out due to its high GWP. It is a blend of R-32 and R-125.
• R-22 (Freon): An older refrigerant that has been phased out in many countries due to its ozone depletion potential.

Why the Shift to Newer Refrigerants?

Older refrigerants like R-22 contribute to ozone depletion and have high Global Warming Potentials (GWP). Newer refrigerants like R-290 and R-32 are more environmentally friendly, with lower GWPs and, in the case of R-290, zero Ozone Depletion Potential (ODP). This shift aligns with global efforts to reduce greenhouse gas emissions and protect the ozone layer.

Table Comparing Refrigerants

Note: GWP values are relative to CO2, which has a GWP of 1.

In summary, while older refrigerants were common in the past, the trend is towards using more environmentally friendly options like R-290 and R-32 in air conditioning systems.