What is the likely issue if an SB-210 without ETV has a "Not Cooling" complaint and a box temperature of 64°F?

When evaluating a "Not Cooling" complaint with a box temperature of 64°F in an SB-210 without an Electronic Throttle Valve (ETV), the focus should be on the specific symptoms and potential causes of cooling system failures.

A restricted liquid line drier can lead to inadequate refrigerant flow to the evaporator coil. If the refrigerant flow is obstructed, the system may fail to cool the air effectively, resulting in higher than desired temperatures inside the box. Since the box has reached 64°F, which is above typical operational temperatures, this suggests that cooling is insufficient. The liquid line drier is a critical component that removes moisture and contaminants from the refrigerant; if it becomes clogged, it restricts the refrigerant from circulating properly, leading to reduced cooling performance.

The presence of air in the system can indeed cause cooling issues, but it typically manifests in different ways, such as fluctuating pressures and reduced efficiency over time rather than an immediate "Not Cooling" scenario. Similarly, restricted airflow through the evaporator can cause cooling problems by affecting the heat exchange process, but considering the steady state of the temperature at 64°F, the more immediate issue is likely to be the restricted flow of refrigerant caused by the drier