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Set Fan and System SwitchesThe switches on the bottom of the thermostat faceplate control the operation of your fan and the heating and cooling
system. Set the Fan switch first and then set the System switch.
Replace BatteriesAs the batteries run low, your thermostat shows the following in the digital display:
a. Make sure that the System switch is set to the OFF position.
b. Open the battery door.
c. Press on the left side of the batteries to remove them.
NOTE: If new batteries are inserted within 20-30 seconds of removing old ones, reprogramming is not
needed. If display is blank, batteries are dead or incorrectly installed and reprogramming is needed.
Switch Setting Result
Fan Auto A single-speed fan turns on automatically with the air conditioner or furnace.
A two-speed fan usually runs on high with the air conditioner and on low with the furnace.
Auto is the normal setting for most homes.
On The fan runs continuously. Use this setting for improved air circulation during special
occasions or for more efficient air cleaning.
NOTE: In a heat-only system, the fan runs continuously only if the fan wire has been con-
nected to the G terminal on the back of the thermostat.
System Cool The thermostat controls your air conditioning system.
Off Both the heating and air conditioning systems are off.
Heat The thermostat controls your heating system.
If you see: Batteries are: You should:
Flashing “bAt Lo” Low Replace the batteries as soon as possible, within the month.
Blank display Dead Replace the batteries immediately. Your heating/cooling system is not
operating.