454 / | HD | VENTILATION |
69 | DF | VEHICLE (E.G., AUTOMOBILE, ETC.) {15} |
143 | DF | .~ Having inlet airway {7} |
156 | DF | .~.~ With air treatment means {3} |
159 | .~.~.~ Heating {2} | |
160 | DF | .~.~.~.~> Having means for combining heated and unheated air |
161 | DF | .~.~.~.~> Having heat exchange core |