What could cause a vapor-cycle cooling system to freeze up?

A vapor-cycle cooling system can freeze up primarily due to the presence of excessive water in the system. When water accumulates, it can lead to the formation of ice, particularly around the evaporator coils. This occurs because the chilled air causes the moisture in the air to condense and freeze, creating a barrier that hampers the airflow and further disrupts the cooling cycle.

In a functioning vapor-cycle system, the refrigerant absorbs heat and evaporates, but when there is excessive water, the system can struggle to maintain the necessary heat exchange processes, leading to freezing conditions. Therefore, while low refrigerant levels, high ambient temperatures, or poor airflow can contribute to cooling inefficiencies, it is the excessive water in the system that directly leads to freezing issues within the vapor-cycle cooling system.