Honeywell CHRONOTHERM IV T8665A - Manual (Page 21)

21 69-1536–3
Replacing the Batteries
This thermostat uses three AA alkaline batteries. Batteries must be installed for programming and operation of
the thermostat and heating (cooling system).
The batteries are located in the wallplate. See illustration.
M10622
INSTALL 3 AA ALKALINE BATTERIES
AS SHOWN, POSITIVE (+) TERMINALS
TOWARD TOP.
WALLPLATE
B
R RC O W Y G
IMPORTANT
Although the thermostat has a low battery
indicator, replace the batteries once a year to
prevent leakage and to prevent the thermostat
and heating/cooling system from shutting down
due to lack of battery power in the thermostat.
1. When the batteries are running low, a REPL BAT
message flashes from one to two months before
the batteries run out completely. Replace the
batteries as soon as possible when the message
flashes.