White Rodgers 1F90-51 Operation Manual page 7

Other than and , the buttons are
Batteries
6-pin connector
located behind the thermostat door. To open the
door, put your fingernail in the indentation at the
top of the door, then pull the door out from the top
and swing it down on its hinges.
On the following pages there are brief descrip-
tions of the display and the thermostat buttons.
2-pin connector
BACK OF THERMOSTAT BODY
7