Refrigerants: A Liquid-Gas Affair

The purpose of a refrigerant is to shift between gaseous and liquid states to absorb and release heat. In its liquid state, the refrigerant can absorb heat better; when it turns to gas, the refrigerant releases the heat into the atmosphere. To better explain the cycle, here's a comparison between two known refrigerants.

The new R-410A, slated to replace the R-22 as the prime refrigerant for future air conditioning units, has a thermal conductivity of 0.054 Btu/hr.-ft. under 60 degrees Fahrenheit. Under the same conditions, the R-22, still being used by older air conditioners, has a thermal conductivity of 0.0515 Btu/hr.-ft.

In its gaseous state, the R-410A's thermal conductivity drops to 0.00805 Btu/hr.-ft., also under 60 degrees Fahrenheit, while that of R-22 also drops to 0.0061 Btu/hr.-ft. Gas doesn't store heat as well as liquid, which explains the drop in thermal conductivity. However, the refrigerant needs this to release the heat into the environment during the refrigeration cycle.

Advances in cooling technology will yield more efficient refrigerants for more efficient units. Despite its enhanced performance, the new refrigerant, R-410A, will continue to work just like the ones that came before it. It would continue to shift between states for a long time to bring comfort at home or in the workplace.