White Rodgers 1F91W-71 Thermostat User Manual


 
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4. What happens if the electricity goes off
or is manually shut off?
If you have not installed a 9 volt alkaline
battery, the display will go blank and the
program will be lost in approximately one
minute. When electricity is restored, the
thermostat will maintain a heating tempera-
ture of 64°F and a cooling temperature of
82°F until you reenter your program. Set-
point temperature will not be displayed.
If a fresh 9 volt Energizer
®
alkaline battery is
installed, the program will be maintained for
about one week with no 24 VAC power
present to the thermostat. See OPERAT-
ING YOUR THERMOSTAT.
5. Why can’t I program the thermostat in
the AUTO mode?
The thermostat can only be programmed in
the HEAT and COOL modes. See PRO-
GRAMMING YOUR THERMOSTAT.
6. What can cause the thermostat display
to freeze or go blank?
A completely blank display may indicate
that power has been lost to the thermostat
and the backup battery is also dead. How-
ever, if there is power to the thermostat and
the display is blank or frozen, static dis-
charge is probably the cause.
During periods of low humidity (especially
during cold weather), you may feel or see a
spark discharge when you touch the ther-
mostat. This may cause the program to be
lost or the thermostat to display incorrectly.