Battery Replacement - Honeywell RTH8500 Operating Manual

Operating Manual

Battery replacement

About your new thermostat
Grasp thermostat and pull to remove
fom wallplate
Insert 3 fresh AAA alkaline batteries
69-1901EF—02
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 warning flash-
es 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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