How do I adjust the speed of the fan on my Air Purifier?

For AP models:  If you want to adjust the fan manually as opposed to allowing it to adjust automatically based on the quality of the air, then you can press the "+" or the "-" key to increase (+) or decrease (-) the speed of the fan.

For AeraMax models: If you want to adjust the fan manually as opposed to allowing it to adjust automatically based on the quality of the air, you can press the Fan icon to increase or decrease the speed of the fan.  When in Turbo setting, pressing the fan icon will return the air purifier to the lowest fan speed setting.