White Rodgers 1F91W-71 - Manual (Page 7)

7
line battery. The battery will provide power
for all functions except the display light and
audio prompting, which work only on 24 VAC
power. If the word BAT is displayed con-
tinuously (non-flashing), the thermostat is
not being supplied with 24 VAC power and
is being powered by the battery alone.
Before removing thermostat from the
wall to replace the battery, remove
24 VAC power from the thermostat at the
breaker/fuse box.
2. You may adjust option switch #4 for auto-
matic changeover from heating to cooling
(see OPERATING FEATURES).
CAUTION !