As the load decreases on a flooded evaporator, what happens to the amount of liquid refrigerant by volume in the evaporator?

When the load decreases on a flooded evaporator, the amount of liquid refrigerant present in the evaporator actually increases. This occurs because a flooded evaporator is designed to maintain a constant level of refrigerant in the evaporator where it is concentrated in liquid form, ready to absorb heat.

As the load decreases, the heat absorption capacity of the evaporator also diminishes. However, the higher liquid refrigerant level ensures that there is sufficient refrigerant available to absorb any remaining heat. Therefore, the refrigerant does not evaporate completely as it would under a heavier load, and instead, it may lead to an increase in liquid refrigerant volume within the evaporator.

Other options incorrectly suggest that the liquid refrigerant volume would decrease or change by a certain fraction. However, in a flooded evaporator scenario, as the load decreases, the tendency is to maintain or even slightly increase the volume of liquid refrigerant to optimize efficiency and heat exchange. Thus, understanding this principle is crucial for effective operation of refrigeration systems.