What Are the Causes of a Dishwasher Making Dishes Chalky on the Surface?

Hard Water

• One of the causes of chalky residue on dishes is hard water. It can leave mineral deposits on the dishes, or it may prevent the detergent from properly dissolving. A liquid detergent may dissolve better in hard water than a powder detergent. In addition, a film or spot remover, white vinegar or citric acid can be added to the rinse agent receptacle and is effective in preventing the chalky residue. If your water is extremely hard, install a water softener to completely resolve the issue.

Water Temperature

• Water temperature may affect the dishwasher's ability to dissolve the detergent, resulting in a chalky residue left on the dishes. Some dishwashers have a heat booster setting to warm the water, but if yours does not, run the hot water on the kitchen faucet for a few minutes before starting the dishwasher cycle. Turning the hot water heater's temperature up is also helpful in increasing the dishwasher's water temperature. The temperature of the water in the dishwasher should be at least 140 degrees Fahrenheit, according to the California Energy Commission.

Water Level

• A low water fill level can prevent dishwasher detergent from properly dissolving and cleaning the dishes adequately, which can leave white film on the dishes. This can happen if the water pressure is too low. Additionally, a clogged or improperly working inlet valve, sump or screen may prevent the dishwasher from filling properly, as well. When the dishwasher doesn't have an appropriate amount of water flowing through it during any cycle, it is unable to effectively clean the dishes, resulting in film or other residue on the dishes.

Washing the Dishwasher

• If the chalky deposits have accumulated in the dishwasher, clean out the dishwasher to remove any traces of the residue. Do not use additional detergent, but instead run several loads with at least 1 cup of white vinegar added to the tub each time. Several cycles of the vinegar wash should effectively remove any mineral or detergent deposits.