Air Conditioning Repair Certification (ETI) Practice Exam 2026 - Free Air Conditioning Repair Practice Questions and Study Guide

When an evaporator is starved for refrigerant, one of the commonly observable indications is sweating at the liquid line filter drier. This occurs because starving the evaporator leads to a lack of sufficient refrigerant, which causes the temperature of the refrigerant in the line to drop significantly. As the refrigerant temperature decreases, humidity in the air condenses on surfaces, leading to sweating or moisture accumulation.

The presence of moisture or sweating at the liquid line filter drier suggests that the refrigerant is not being adequately utilized in the evaporator, causing abnormal temperature differences throughout the system. This moisture accumulation is a clear sign of issues with refrigerant flow, highlighting the system's inefficiency in transferring heat.

Observing sweating on the compressor, excessive airflow across the evaporator, or low energy consumption would not typically indicate an issue specific to refrigerant starvation in the same direct way as sweating at the filter drier does. Instead, each of these could signify other operational problems of the air conditioning system but not directly point to a refrigerant starvation condition.