This twisty part which is found in an A/C unit regulates the refrigerant flow for the indoor coil. It is called a thermostatic expansion valve, or TXV, for short. The TXV makes sure the A/C unit maintains maximum efficiency by allowing only a certain amount of refrigerant to flow into the evaporator. This control over the flow of refrigerant is necessary to make the evaporator as efficient as possible. It also prevents refrigerant from
