Hierarchy classification:

1. top of the aat hierarchies
2. Objects Facet
3. Visual and Verbal Communication (hierarchy name)
4. Visual Works (hierarchy name)
5. visual works (works)
6. [visual works by form]
7. [visual works by form of image]
8. [images by method of representation]
9. [images by method of projection]
10. orthographic projections (images)
11. plans (orthographic projections)
12. building plans
13. utility plans
14. HVAC plans

Anotations

Scope note:

Refers to plans representing the layout and configuration of heating facilities in a structure. They typically include the position of boilers, radiators, or other heating sources, pipes, air conduits, and the number of rooms and desired temperatures. They may include specialized symbols and conventions, such as the flow of steam or heated air depicted in red, and the return in blue.