Final answer:
The Thermostatic expansion valve (TXV) can respond to changes in system conditions by adjusting the flow of refrigerant based on temperature and pressure variations.
Step-by-step explanation:
Among the listed metering devices, the Thermostatic expansion valve (TXV) is designed to respond to changes in system conditions such as temperature and pressure. Fixed orifice and capillary tube metering devices are generally not responsive to changing conditions but instead provide a constant flow rate. The float valve is used in some refrigeration systems to maintain a constant level of liquid refrigerant, but it does not respond dynamically to system conditions like a TXV does.
The TXV works by using a sensing bulb filled with a charge that reacts to the temperature of the refrigerant, controlling the flow of the refrigerant through the valve. As system conditions fluctuate, the pressure within the sensing bulb changes, causing the valve to adjust and maintain optimal refrigeration system performance.