What is often the primary cause of a flooded evaporator?

The primary cause of a flooded evaporator is typically an overcharged system. In refrigeration systems, overcharging occurs when there is an excess of refrigerant within the system, which leads to higher pressures than the system is designed to handle. This can result in liquid refrigerant entering the evaporator instead of just vapor.

In an ideal functioning system, the refrigerant evaporates within the evaporator coil, absorbing heat and cooling the air around it. However, when the volume of refrigerant is too high, there is insufficient space and conditions for the refrigerant to fully vaporize, which causes liquid refrigerant to accumulate, leading to flooding of the evaporator. This flooding can hinder the system's ability to cool effectively and may result in compressor damage over time due to liquid slugging.

In contrast, other potential causes like a blocked suction line, inadequate airflow, or a stuck expansion valve do play roles in system performance, but the typical direct cause of flooded evaporators is more closely associated with overcharging the system. Each of these scenarios can lead to the inefficiency of the system but does not directly cause a flooded evaporator in the same way that an overcharged system does.