Is their gas in home air conditioners?

Yes, most home air conditioners use a type of refrigerant gas, which is a chemical compound used to transfer heat from one place to another. In the case of air conditioners, the refrigerant helps to cool the air by absorbing heat from inside the home and releasing it outside.

The refrigerant gas is contained within the air conditioner's cooling system and circulates through a closed loop. It starts as a high-pressure liquid, but as it passes through the expansion valve it converts into a low-pressure gas. This expansion causes the refrigerant to cool down, and as it passes through the evaporator coils it absorbs heat from the air inside the home. The refrigerant gas then passes through the compressor, which increases its pressure and temperature, before flowing through the condenser coils where it releases the absorbed heat to the outside air. The refrigerant then cycles back to the expansion valve, and the process repeats.