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RTH4300B Programmable Thermostat
About your new thermostat
Select the fan setting
Set the
FAN
switch to Auto or On.
In “Auto” mode (the most commonly used
setting), the fan runs only when the heat-
ing or cooling system is on.
If set to “On,” the fan runs continuously.
Use this setting for improved air circula-
tion, or for more efficient air cleaning.
Set
FAN
switch to choose whether the fan
runs continuously or only as needed.