Using Fans

iStat Menus can help control the speed of fans in your Mac. iStat Menus can’t lower fans below the speed the System Management Controller (SMC) would normally use, but it can raise the fan speeds.

There are four main modes of fan control in iStat Menus.

  1. Let the system control fan speeds.
  2. Fan sets.
  3. Automatic fan set switching.
  4. Manual fan speed sliders in the Fan menu in the sensor menubar item.

System Controlled fan speeds

With the fan control set to System Controlled from the Sensor menu, iStat Menus will not control fans at all — your Mac’s fans will act as if iStat Menus is not installed.

Fan sets

If you’d like to create a set of fan speeds that can be recalled at any time, this can be done with fan set. To create a fan set:

This will create a fan set. You can now edit the various fan speeds you’d like for this set. To recall the set, choose it from the Fans menu in the sensor menubar item.

Automatic fan set switching

iStat Menus can switch to a different fan set, based on rules you provide. That will let you create a set for normal operation, and also create fan sets to be used under different circumstances. To use automatic fan set switching, choose Automatic from the Fans menu in the sensor menubar item.

To create rules for automatic fan set switching:

In the example above, iStat Menus will use “My Fan Set” when any sensor is above 80ºC. Using automatic fan set rules, you can increase the speed of fans when certain events are triggered. This means it is possible to do many things, including:

The Default Fan Set popup button chooses which fan set will be used normally (when none of the automatic fan set rules are met).

Manual fan speed sliders

Fan speeds can be set directly via the sliders in the Fans menu in the sensor menubar item. If the manual fan speed sliders are edited, those speeds will be used.

Please note that manual fan speed slider settings are not saved across reboots. For more permanent settings, please use fan sets.

Fan control issues

If you’re experiencing issues with fans, Resetting your SMC may fix the problem.