Which type of refrigerant would typically be used with a TXV?

A thermal expansion valve (TXV) is a type of metering device used in refrigerant systems to control the flow of refrigerant into the evaporator. It adjusts the flow based on the cooling demand and the temperature of the refrigerant leaving the evaporator, ensuring optimal efficiency and performance of the system.

All types of refrigerants, including hydrofluorocarbons (HFCs), chlorofluorocarbons (CFCs), and natural refrigerants like ammonia, can be compatible with a TXV. HFCs are commonly used in modern refrigeration applications due to their lower ozone-depletion potential compared to CFCs. While CFCs have largely been phased out due to their environmental impact, they can still be used in older systems that might have originally been designed with TXVs. Similarly, natural refrigerants like ammonia are prevalent in industrial refrigeration, where their efficiency and low environmental impact make them suitable for systems utilizing TXVs.

Therefore, all the mentioned refrigerants can effectively work with thermal expansion valves in their respective systems, which validates the choice of "All of the above."