GE RAK148P1 Owner's Manual & Installation Instructions page 19

Combination failure (power failure & low battery).
The programmable thermostats with battery backup also
will indicate a combination failure; that is, both a low battery
condition as well as a power failure condition. After the power
is restored, the following may be indicated:
Combination failure, Off mode
The thermostat will display a low
battery indication, as well as a power
failure indication ("12:00"). The display
will toggle between the low battery
screen and the "12:00" screen.
Combination failure, Cool mode
The thermostat will display a low
battery indication, as well as a power
failure indication ("12:00"). The display
will toggle between the low battery
screen and the "12:00" screen
(Non-Program Cool Mode Shown).
Combination failure, Heat mode
The thermostat will display a low
battery indication, as well as a power
failure indication ("12:00"). The display
will toggle between the low battery
screen and the "12:00" screen
(Non-Program Heat Mode Shown).
OFF
PM
OFF
COOL
COOL
PM
HEAT
PM
HEAT
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