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} |
658 | DF | .~.~.~ Having heat-absorbing fin or plate {4} |
661 | .~.~.~.~ Plate surface with conduit secured thereto |