What component ensures the correct amount of refrigerant flows in a heat pump system?

The thermostatic expansion valve (TXV) plays a crucial role in regulating the flow of refrigerant within a heat pump system. Its primary function is to control the amount of refrigerant that enters the evaporator coil, which is essential for maintaining the system's efficiency and performance.

The TXV does this by responding to the temperature and pressure of the refrigerant in the evaporator. By modulating the flow based on these parameters, it ensures that the evaporator is supplied with the optimal amount of refrigerant needed for heat absorption. This precise control helps prevent conditions like flooding or starvation in the evaporator, which could impair the overall performance of the heat pump.

Other components, such as the compressor and accumulator, play vital roles in the overall operation of the system but do not directly control the flow of refrigerant in the same manner. The compressor circulates the refrigerant and increases its pressure, while the accumulator helps manage excess refrigerant and prevent liquid refrigerant from reaching the compressor. The liquid line filter dryer serves to filter out debris and moisture but does not regulate flow. Thus, the TXV is the key component responsible for ensuring the correct amount of refrigerant flows in a heat pump system, making it the correct choice.