What is the maximum length for listed air duct connectors?

The maximum length for listed air duct connectors is set at 14 feet according to the North Carolina Mechanical Code. This limit is established to ensure optimal airflow and system efficiency in HVAC installations. Longer connectors can lead to increased friction loss, reducing the overall effectiveness of the air distribution system. By adhering to this maximum length, practitioners can ensure that the system operates within safe and efficient parameters, minimizing potential issues such as reduced airflow and increased noise levels.

In practical terms, maintaining the specified length helps ensure the connectors function as intended, reduce strain on the entire duct system, and prevent thermal losses. When choosing to implement air duct connectors, it's important to consider both the length limitation and the type of material used to maintain compliance with code and ensure a functional and effective HVAC system.