Rheem Comfort Control2 Installer's Manual page 8

The display will change to Start-up, Hold screen showing
the actual temperature, SYSTEM position (HEAT)
mode, FAN setting (AUTO), HOLD AT with the setpoint
temperature 62 for heat or 85 for cool and real time clock
(hour, minute, AM or PM, day).
Communications Systems
The ClimateTalk protocol will set the identification of the individual nodes connected
TM
to the thermostat. The Network Device display will appear during initial power up and
when a new device is found on the network.
8  Installer's Guide