How do I operate the one-button control panel on the OxyPure?

Plug in the unit (it will beep once), then press the Power icon to cycle through fan speeds: first press activates low speed (400 RPM), second press increases to medium speed (800 RPM), third press increases to high speed (2450 RPM), and fourth press turns the unit off. The LED lights indicate which speed level is active. (Page 8)