8402.90.00 - Parts

This HTS category, 8402.90.00, encompasses "Parts" specifically for steam or other vapor generating boilers (excluding central heating hot water boilers capable of producing low pressure steam) and super-heated water boilers. This includes any component, piece, or accessory that is designed and intended for incorporation into, or use with, these types of boilers. The classification is determined by the part's essential character and function in relation to the complete boiler unit.

It is crucial to distinguish this category from its siblings. While the broader heading 8402 covers the complete boilers themselves (8402.11 through 8402.19 for steam boilers and 8402.20 for super-heated water boilers), this subheading is exclusively for the individual components and not the finished boiler units. Therefore, classification under 8402.90.00 requires that the item be a distinct part, rather than a fully assembled boiler.

Within this "Parts" category, further distinctions are made to refine classification. The subcategories include "Heat exchangers" (8402.90.00.10), which are components designed to transfer heat between fluids, and "Other" (8402.90.00.90) for all remaining parts not specifically enumerated. This breakdown allows for more precise identification of components like tubes, furnaces, safety valves, control mechanisms, and insulation, ensuring they are correctly categorized based on their specific function and design within the boiler system.