We recommend regular cleaning of the Steam Tank to prevent damage to the machine from mineral deposits. The frequency of cleaning will depend on the type of water you are using and how much mineral deposit build up forms. Always unplug before cleaning. Put 1/3 cup white vinegar and 1/3 cup distilled water in machine and let sit overnight. Pour out vinegar and water solution (refer to user manual for proper emptying instructions). Refill Steam Tank with purified water, plug in machine and run “Steam” cycle for 10 minutes. Let Steam Tank cool and scrub with a cleaning brush if necessary. Rinse with purified water to eliminate any remaining vinegar taste. Empty tank and fill with clean water before cooking