RTH7400/RTH7500 Series
19 69-2744ES—01
MCR28101
M28103
Battery replacement
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 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.
Grasp thermostat and pull to
remove from wallplate
Insert 2 fresh AA alkaline batteries