When bending flexible duct, a minimum radius of which dimension is recommended?

When bending flexible duct, the recommended minimum radius is typically based on the diameter of the duct. This is because the diameter determines how tightly the duct can be curved without compromising its structural integrity or airflow characteristics. A minimum bend radius that is too tight can lead to kinks or constrictions, which can impede airflow and result in increased pressure losses, noise, and potential damage to the duct material.

Maintaining a bend radius that is at least equivalent to the diameter helps ensure that the flexible duct remains functional, allowing air to flow freely and reducing the risk of restricted airflow due to sharp turns. This principle is particularly critical to uphold efficiency in heating, ventilation, and air conditioning (HVAC) systems.

Opting for any other dimension such as length, width, or height does not accurately address the physical characteristics and operational needs of flexible ducting. Those dimensions would not provide the necessary context for ensuring proper airflow or duct longevity when installed in HVAC systems.