How do I change the carbonation level for sparkling water?

When the Sparkling Water Icon is turned on, you can change the carbonation level by pressing the Sparkling Water button. The carbonation level will cycle through: Medium (Level-2) → Strong (Level-3) → Weak (Level-1) → Medium (Level-2). The new carbonation level is applied the next time the refrigerator makes sparkling water. Production times vary: Level 1 takes about 10 minutes, Level 2 about 20 minutes, and Level 3 about 30 minutes. (Page 23, 32-33)