What temperature triggers the DUCT TEMP annunciator?

The correct temperature that triggers the DUCT TEMP annunciator is 300 ºF. This threshold is significant as it indicates a potentially unsafe condition where the temperature within the ductwork could lead to equipment or fire hazards if not addressed.

Operating temperatures above this level necessitate immediate attention to prevent damage to the system or to ensure the safety of personnel. Thus, the choice of 300 ºF aligns with safety protocols established in aviation and maintenance practices, aimed at preventing overheating and maintaining proper operational conditions within the aircraft.

Choosing a lower temperature, such as 250 ºF, 275 ºF, or 325 ºF, would not align with the established safety parameters for duct temperature monitoring, as they either do not provide adequate warning for overheating or set an unnecessary alarm at too high of a temperature. Therefore, the 300 ºF figure not only serves as a critical operational benchmark but also plays a vital role in safety management within the aircraft systems.