Honeywell RTH6400 Operating Manual page 20

Operating Manual
Battery replacement About your new thermostat
Press down and pull to remove.
Replace Battery
Insert fresh AA alkaline
batteries, then reinstall
battery holder.
69-2211EF—05
Install fresh batteries immediately when the
REPLACE BATTERY warning begins flashing. The
warning flashes about two months before the bat-
teries are depleted.
Even if the warning does not appear, you should
replace batteries once a year, or before leaving
home for more than a month.
If batteries are inserted within two minutes, the
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time and day will not have to be reset. All other
settings are permanently stored in memory and
do not require battery power.
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