What size duct work is run to the returns at Wendy's?

The correct answer is based on common practices in commercial HVAC system design, particularly in fast-food restaurants like Wendy's. Typically, the size of ductwork in return air systems is determined by the volume of air that needs to be moved, the size of the space, and the specific requirements of the HVAC system to maintain comfort and efficiency.

In many cases, 16-inch ductwork is often sufficient to handle the airflow requirements for the return vents in a restaurant setting. This size allows for efficient air circulation, which is particularly important in environments with higher heat loads from cooking equipment. Additionally, this diameter balances airflow with noise considerations, ensuring that the system operates quietly and effectively.

Choosing a smaller size might not provide adequate airflow, while a larger size may lead to unnecessary costs and increased installation complexity. Thus, 16-inch ductwork is generally the standard choice that meets both performance and installation criteria for a restaurant like Wendy's.