| 126 / | HD | STOVES AND FURNACES | 
| 569 | DF | SOLAR HEAT COLLECTOR {18} | 
| 572 | DF | .~ With control means energized in response to actuator stimulated by condition sensor {3} | 
| 573 | DF | .~.~ Including sun position tracking sensor {7} | 
| 576 |  | .~.~.~ With motor {1} | 
| 577 | DF | .~.~.~.~> With gear |