What is the purpose of the metal plates installed around an uncased evaporator coil?

The purpose of the metal plates installed around an uncased evaporator coil is primarily to force air flow through the coil. These plates are designed to direct and manage the air that passes over the coil, ensuring that a sufficient amount of air is circulated through it for effective heat exchange. This is essential because the efficiency of the cooling system relies heavily on optimal air flow, which allows the evaporator coil to absorb heat from the air effectively, thereby cooling the surrounding environment.

While the other options may seem plausible, they do not capture this function accurately. Protecting the coil or supporting its weight could be secondary functions depending on the design and installation, but the primary role of those metal plates is to enhance the application of air flow. Enhancing aesthetic appeal is typically not a priority in the functional design of refrigeration systems; the focus is primarily on performance and efficiency.