How do I control my fan with the Nest Learning Thermostat?

You can turn on the fan of your heating or cooling system immediately, for a few minutes every hour, or for a certain period of time every day.

Many people like to use the fan independently of heating and cooling. It keeps rooms from getting stuffy, circulates the air to create an even temperatures across the house, and helps to cool down your home on summer nights. You can even save energy by using the fan instead of air conditioning on temperate days.

Nest’s fan control offers a simple way to turn the fan on when you need it, without having to manually switch it on and off. For example, you can set the fan to run all night and turn off in the morning automatically. Or you could schedule it to run from 3-6pm when the kids get home from school. You can also tell Nest to run the fan for 15 minutes every hour to keep things from getting stuffy.

When the fan is on without heating or cooling, a fan icon will appear on the display.

Who can use Advanced Fan Control?

Only systems that can control the fan separately from heating and cooling can use Advanced Fan Control. These systems have a separate G wire to control the fan. If you don’t have separate fan control (e.g., a wire inserted in the G connector on Nest) you won’t see the FAN option in SETTINGS and won’t have access to Advanced Fan Control.

How does Advanced Fan Control work?

To reach Advanced Fan Control from your Nest thermostat, go to SETTINGS > FAN. You’ll see the following options:

OPTION	EXPLANATION
AUTOMATICALLY	If AUTOMATICALLY is selected, your fan will turn on automatically as needed when heating or cooling is engaged. This is how Nest usually controls the fan.
EVERY DAY	If you select EVERY DAY, you can set your fan to come on for a specific time period each day, to run continuously, or to turn on for 15, 30 or 45 minutes of every hour. In the example above, you’d be running the fan for 15 minutes of over the course of any 60 minute period from noon until 4pm every day. Nest will take into account time that the fan as already run because of heating or cooling. So if the fan is set to run for 15 minutes an hour but the AC has already been running for 30 minutes, the fan won't come on. However, if the AC had only run for 10 minutes, then Nest will turn on the fan to make sure that at least 15 minutes of total fan time have run during the last rolling 60 minute period.
START NOW	If you just want to run your fan right now and don’t need to schedule it for every day, select START NOW. Set how long you’d like the fan to run, from 15 minutes to 12 hours.
DONE	Once you’ve set your fan the way you’d like, just select DONE.