Step 6. Mount The Thermostat - Honeywell CT3650 Owner's Manual

When the batteries are running low, a REPL BAT message flashes for one to
two months before the batteries run out completely. Replace the batteries as
soon as possible once the message flashes.
IMPORTANT
Although the thermostat has a low battery indicator, replace the
batteries once per year to prevent leakage and to prevent the ther-
mostat and heating/cooling system from shutting down due to lack
of battery power in the thermostat.
If you insert new batteries within 20 to 30 seconds of removing the old
batteries, the system retains the current time and day. If the display is blank,
the batteries are dead or installed incorrectly. You must reset the time and
day. Refer to Set the Clock for instructions.
As a precaution when leaving home for longer than a month, change batteries before leaving to prevent
the system from shutting down due to lack of power. Always use fresh alkaline batteries. Nonalkaline
batteries do not last as long. They also can leak, causing damage to the thermostat and the wall surface.
Honeywell recommends Energizer® batteries.

STEP 6. MOUNT THE THERMOSTAT

A.
ENGAGE TABS AT TOP
OF THERMOSTAT
AND WALLPLATE.
69-1285—2
B.
PRESS LOWER
EDGE OF CASE
TO LATCH.
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M12703