ESCO Light Commercial Refrigeration Practice Exam 2025 - Free Refrigeration Practice Questions and Study Guide

In low-temperature refrigeration systems, the proper operation of the evaporator is critical for efficient cooling and preventing system failures. Periodic defrosting is essential because frost can accumulate on the evaporator coils, insulating the coils and preventing them from effectively transferring heat. When frost builds up, it decreases the heat exchange efficiency, which can lead to higher energy consumption, reduced cooling performance, and potential damage to the evaporator.

Defrosting helps maintain optimal airflow across the coils and ensures that the refrigerant can evaporate properly within the evaporator, thereby maintaining the desired low temperatures effectively. A properly functioning defrost cycle will optimize the overall performance of the refrigeration system, prolong its lifespan, and maintain safety standards.

Other methods such as adjusting fan speed or using higher pressure may impact the operation but are not focused specifically on addressing frost buildup. Frosting periodically does not facilitate proper functioning; instead, it would exacerbate the issues related to frost accumulation. Thus, the best practice for ensuring the proper operation of a low-temperature evaporator is to incorporate a regular defrosting schedule.