Carrier 33CS420-01 Owner's Manual page 39

Locking/Unlocking theX ad
To prevent unauthorized use of the thermostat, the front panel
buttons may be disabled. To disable, or 'lock' the keypad, press
and hold the M©DE button, While holding the M©DE button,
press the UP and DOWN buttons together. The _ icon will
appear on the display, then release the buttons.
Press all three /
buttons in the order ,L_
--->
outlined above for \ ?
keypad lockout \
To unlock the keypad, press and hold the M©DE button, While
holding the MODE button, press the UP and DOWN buttons
The ,_ icon will disappear from the display, then together.
release the buttons.
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