Honeywell CT3500 Owner's Manual - Page 10

q If the thermostat is already mounted on the wall, remove the thermostat by placing your thumb between the thermostat and wallplate and pulling the thermostat up and away as shown. 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 thermostat 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 M16424 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 60 70 80 90 the system from shutting down due to lack of power. Always use fresh alkaline batteries. Nonalkaline 60 70 80 90 batteries do not last as long. They also can leak, causing damage to the thermostat and the wall surface. STEP 6. SET FAN OPERATION SWITCH The thermostat fan operation switch, labeled FUEL SWITCH is factory set in the F position. This is the correct setting for most systems. If your system is an electric heat system, set the switch to E. The E setting allows the fan to turn on immediately with the heating or cooling in a system where the G terminal is connected. 69-1199-4 10 FUEL SWITCH M12676