How does Control Setting work?

This advanced setting is for users who deal with severe air pollution. The default setting for the unit is moderate and should meet the needs of most people. The moderate setting displays as four bars on the right-hand side of LCD control panel. System Setting: To access High standby mode, press and hold the “Auto” button for more than 5 seconds. You will hear a “ding” sound, and see the Control Setting bars go from High, to Low, to Moderate, then repeat the sequence and start blinking. If you release the “Auto” button when “High” is blinking, the system is set to High Mode (6 bars) and so on.