| 165 / | HD | HEAT EXCHANGE |
| 200 | DF | WITH TIMER, PROGRAMMER, TIME DELAY, OR CONDITION RESPONSIVE CONTROL {14} |
| 201 | DF | .~ Having heating and cooling capability {13} |
| 222 | DF | .~.~ Humidity control {2} |
| 230 | ![]() | .~.~.~ Dewpoint controlled (e.g., control of cooling means by downstream temperature sensor to maintain controlled dewpoint of downstream air, etc.) |