Carrier TC-PHP01-BLK Installation Manual page 20

Option 18 - Backlight Configuration
Default: OF
Options: On (ON), Off (OF)
Description: When ON is selected and the thermostat is not battery operated,
a low level continuous display backlight is always on. With OF selected, the
backlight is only on for a short time after the door is opened or a key is
pressed. Continuous backlight is not available with battery operation.
Option 21 - Keypad Lockout
Default: Off (OF)
Options: On (ON), Off (OF)
Description: With OF selected, the keypad cannot be locked. With ON
selected the keypad will be locked and can be unlocked by simultaneously
pressing the UP and DOWN keys for 5 seconds. Once unlocked, it will re lock
2 minutes after the last keypad press. A "lock" icon is displayed while it is
locked.
Option 24 - Programmable/Non-Programmable
Default: Programmable (P)
Options: Programmable (P), Non-programmable (nP)
Description: Enabling nP mode disables programming. The clock is displayed,
but the program schedule, the HOLD and TEMPORARY HOLD functions are
disabled.
Option 25 - Number of Programmable Periods
Default: 4
Options: 2, 4
Description: The number of programmable periods available in your schedule
per day.
SSelecting 2 allows 2 programming periods per day, P1 and P2. For
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