The Fan will remain OFF if a thermostat’s System is set to OFF and Fan is set to AUTO.
This also means no heating or cooling will be active.
If Fan is set to AUTO and System is set to AUTO, HEAT, or COOL: the fan will only run during a Heating or Cooling cycle.
The fan must run during a heating or cooling cycle to properly heat or cool the room.
- When will a thermostat run the fan?