| 126 / | HD | STOVES AND FURNACES |
| 569 | DF | SOLAR HEAT COLLECTOR {18} |
| 634 | DF | .~ With means to convey fluent medium through collector {7} |
| 651 | DF | .~.~ Conduit absorber structure {9} |
| 668 | ![]() | .~.~.~ Rectangular nonmetallic conduit {1} |
| 669 | DF | .~.~.~.~> Having internal partition |