What should a technician ensure when selecting wire for a heating system?

When selecting wire for a heating system, ensuring that it meets NEC (National Electrical Code) class ratings is crucial for compliance and safety. The NEC provides guidelines on the types of wires that can be used in various applications, ensuring they can handle the electrical loads and environmental conditions they will be exposed to. Proper ratings help prevent overheating, electrical shorts, and fire hazards, making this consideration essential for the safety and durability of the heating system.

Additionally, using the appropriate wire gauge, insulation type, and ensuring compatibility with the thermostat are also important factors for proper system function, but the primary focus of NEC compliance guarantees adherence to national safety standards, making it a critical aspect of wire selection in heating installations.