What is an electric heating element enclosed in a heat- and corrosion-resistant steel tube called?

The term for an electric heating element enclosed in a heat- and corrosion-resistant steel tube is "encapsulated heater." This type of heater is designed to effectively protect the heating element from harsh environments, including moisture and corrosive substances, which can significantly extend its lifespan and ensure safer operation. The encapsulation provides insulation properties and helps maintain the efficiency of the heating element, allowing for better heat transfer.

In contrast, tubular cased wire, while it may refer to a method of enclosing wire, does not specifically denote a heating element within a protective tube designed for heating applications. Other options like sealed element and protected coil refer to different forms of heating devices but do not capture the specific characteristics of an encapsulated heater. Understanding the correct terminology is essential for HVACR professionals, as it aids in identifying the right equipment for specific applications.