Honeywell TH8000 Series Operating Manual page 22

Operating Manual
Battery replacement About your new thermostat
Grasp thermostat and pull to remove
fom wallplate
Insert 3 fresh AAA alkaline batteries
Batteries are optional (to provide backup
power) if your thermostat was wired to run on
AC power when installed.
Install fresh batteries immediately when the
LO BATT warning begins flashing. The warn-
ing flashes about 30 days before batteries 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.
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