If a low temperature ammonia booster compressor's discharge temperature drops suddenly from 120°F to 80°F, what is indicated?

When the discharge temperature of a low temperature ammonia booster compressor drops suddenly from 120°F to 80°F, it indicates that there may be liquid refrigerant present in the suction line. Compressors are designed to compress vapor, and the presence of liquid can cause issues such as flooding or slugging within the compressor. This can lead to a drop in discharge temperature because liquids do not compress like gases, and their presence can disrupt the normal operation of the system.

The drop in temperature points to the possibility of liquid refrigerant not fully evaporating before it reaches the compressor suction. When a compressor ingests liquid refrigerant, it may not produce the expected discharge temperature, as the compressor will struggle to operate efficiently under those conditions. Identifying the presence of liquid refrigerant in the suction line is critical as it can protect the integrity of the compressor and optimize the system’s overall performance.