Calcium Buildup in a Dishwasher

Citric Acid Powder

• Citric acid, a white crystal powder, breaks down hard water deposits from dishwashers. You can find citric acid powder at your local supermarket in the dish detergent aisle. Pour 1/2 cup of citric acid powder into the bottom of an empty dishwasher. Run the dishwasher through a complete cycle to allow the citric acid to dissolve the calcium buildup. When you handle citric acid, wear gloves to prevent irritation or burns to your skin.

White Vinegar

• Acidic distilled white vinegar breaks down built-up calcium. Vinegar also neutralizes odors. Empty the dishwasher before running a cycle with vinegar so the vinegar can reach all of the calcium buildup. Pour 1 cup of white vinegar into the bottom of the dishwasher and run it through a complete cycle. After the dishwasher completes a cycle, return the dishes to the appliance. Fill the rinse reservoir with white vinegar each time you clean dishes to prevent a buildup from occurring.

Baking Soda

• Sometimes a thick buildup of calcium or other minerals forms in different locations inside the dishwasher. Thicker areas of calcium may not dissolve completely. Apply a paste that consists of an equal amount of baking soda and white vinegar to problem areas. Spread the baking soda paste over the buildup and allow it to remain for 30 minutes to 1 hour. After the paste sits, scrub the area with a soft-bristled brush to loosen the buildup. Rinse the dishwasher with clean water to remove the paste.

Lemon Juice

• Lemon juice works as effectively as citric acid powder and white vinegar, due to the acid content in the juice. You can pour 1 cup of lemon juice into the dishwasher, or fill a spray bottle with the liquid. Spray the entire interior surface of the dishwasher and let the juice rest for up to 1 hour. Run the dishwasher through one complete cycle after applying the lemon juice to rinse it off thoroughly. Lemon juice also leaves behind a slight lemon scent.