Carrier Debonair 2 Owner's Manual page 23

About Advanced Features & Operation
LOCKING COVER w/Tamper Proof Screws
COOL
AUTO
HEAT
OUTSIDE SENSOR - To view an Outside Sensor (step #10, page 13), press
and hold the FAN button for two seconds until the Outside icon appears.
If an optional outside sensor is connected, the outside temperature will
appear on the display. To exit the outside temperature display, press any
button.
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