A.O. Smith CAHP-MC-38 Installation, Operation And Maintenance Instructions page 27

Area① Time
Information
Area① Function
Buttons
Display
TIME Display the current day of the week and the clock time ( hour & minute).
The icon indication of the timer status. The timer is ON if the icon is
displayed and is off otherwise.
Communication error alarm. If the central controller could not get the
timing information from the heat pump units, this icon will be displayed
diamatically (size change), and the timer function will be disabled.
Display "ON" when the system is off. To turn on the system, press the
ON
button below this icon.
Display "OFF" when the system is on. To turn off the system, press the
button below this icon.
Press the button below this icon to enter the related function ineterfaces.
FUNC
Press the button below this icon to enter the "HELP" interface.
HELP