What is the purpose of a fan interlock in electric duct heaters?

A fan interlock in electric duct heaters is a safety feature designed to prevent the heater from operating when the fan is not running. This is crucial because electric duct heaters generate heat that must be distributed through the air system; without airflow, the heat can accumulate and lead to overheating or even damage to the heater itself.

By ensuring that the heater cannot operate unless the fan is functioning, the interlock protects both the equipment and enhances the safety of the system. This integration prevents hazardous conditions and ensures that the system only operates effectively in delivering heated air throughout the ducts.

While regulating airflow, enhancing heating efficiency, and conserving energy are important functions in HVAC systems, they do not specifically address the critical safety concern that the fan interlock is designed to resolve. Therefore, recognizing the primary role of the fan interlock is essential for understanding its importance in maintaining safe and efficient heater operation.