Carrier Debonair 2 Owner's Manual page 8

Selecting the Heat or Cool Mode
Cool Only
Step #4 = 2 in the Advanced Setup section, page 11.
Cooling Only
The COOL setting indicates the temperature
that the room has to rise to before the cooling
source will turn on to cool the room.
OFF
OFF indicates both heating and cooling
are turned off.
2-Pipe Operation
Fan
7
Press
MODE