GCAP Industrial Ammonia Refrigeration Training 2025 – 400 Free Practice Questions to Pass the Exam

A sudden drop in the discharge vapor temperature of a low-temperature ammonia booster compressor to 80°F is typically indicative of possible liquid present in the suction line. This can occur if liquid refrigerant is being drawn into the compressor, which can lead to flooding. In a refrigeration system, the compressor is designed to compress vapor, and the presence of liquid can disrupt this process.

When liquid enters the compressor, it can cause significant mechanical issues and inefficiencies, such as reduced capacity and potential damage to the compressor components. Therefore, a drop in the discharge temperature warrants investigation into the state of refrigerant in the suction line.

This scenario highlights the importance of maintaining proper conditions in the refrigeration system to prevent liquid carryover into the compressor, which can adversely affect the system's performance and reliability. Other scenarios, such as a decrease in ambient temperature or changes in efficiency, would not directly explain this specific and crucial drop in discharge vapor temperature as effectively as the presence of liquid in the suction line.