Select Fan Setting (Auto/On) - Honeywell RTH2310 Operating Manual

RTH2310 Programmable Thermostat
Select the fan setting
Aulo On
Fan
Use the Fan switch to select the fan mode of operation.
Auto * The fan runs only when heating or cooling is activated. However, if you have a gas or
fuel oil furnace, when heating is activated, the fan will start only when the air coming out
of the vents is warm enough. The fan will keep on running after heating stops until the
air is no longer warm enough.
On The fan is always running. Use this setting for improved air circulation or for more efficient
air cleaning.
NOTE: The Fan switch is not used if the fan is not connected to the thermostat.