Replace Batteries; Accessories/Replacement Parts - Honeywell RTH3100C Owner's Manual

Battery replacement
Batteries are optional if your thermostat
was wired for AC power when installed.
Install fresh batteries immediately when
the REPLACE BATT warning begins flashing.
Even if the warning does not appear, you
should replace batteries once a year,
or before leaving home for more than a
month.
Batteries provide backup power to the
display during power interruptions.
All settings are permanently stored in
memory, and do not require battery power.

Accessories/replacement parts

To order, please call Honeywell Customer Care toll-free at 1-800-468-1502.
Cover plate*....................Part No. 50002883-001
*Use to cover marks left by old thermostats.
Turn thermostat over,
insert fresh AA alkaline
batteries, then reinstall
thermostat.
11
Pull at bottom to remove
thermostat from wallplate.
M28331
M28332