| 165 / | HD | HEAT EXCHANGE |
| 120 | DF | WITH IMPELLER OR CONVEYOR MOVING EXCHANGE MATERIAL {1} |
| 121 | DF | .~ Mechanical gas pump {1} |
| 122 | | .~.~ Heating or cooling means and gas pump in housing {2} |
| 123 | DF | .~.~.~> With injector-type gas pump |
| 124 | DF | .~.~.~> Verging gas flow {2} |