What happens if I set the Fan switch to 'Auto'?
When the **Fan** switch is set to 'Auto', the fan only runs when the heating or cooling system is actively operating. If you want continuous fan operation, set it to 'On'.
From the official Honeywell TH3210D1004 Thermostat manual, page 4
Have a follow-up question?
Answers from the official manual.
Common questions