York LX series Owner's Manual page 40

Installer Setup
Locking/Unlocking the Keypad
To prevent unauthorized use of the thermostat, the front panel buttons may be
disabled. To disable, or 'lock' the keypad, press and hold the MODE button.
While holding the MODE button, press the WARMER and COOLER buttons
together. The icon will appear on the display, then release the buttons.
Press all three
buttons in the order
outlined above for
keypad lockout
To unlock the keypad, press and hold the MODE button. While holding
the MODE button, press the WARMER and COOLER buttons together.
The icon will disappear from the display, then release the buttons.
I
Am
2:00 74
MO
C L S
OO ET
78
H S
Outdoor EAT ET
85 68
MODE
Page 32