126 / | HD | STOVES AND FURNACES |
99 R | DF | HOT-AIR FURNACES {24} |
110 R | .~ Compressed air {6} | |
110 A | DF | .~.~> Blower and air damper |
110 AA | DF | .~.~> Downflow of air being heated |
110 B | DF | .~.~> Unit heaters |
110 C | DF | .~.~> Gas and air mixing |
110 D | DF | .~.~> Unitary fan and heater |
110 E | DF | .~.~> Thermally actuated air-propelling means |