Dishwasher Not Cleaning Dishes Properly: Causes and Solutions

A dishwasher that doesn't clean properly defeats its purpose. Before assuming a major repair is needed, consider these common causes and solutions.

Water temperature is critical for proper cleaning. Your dishwasher needs water at 120-140 degrees Fahrenheit. Run the kitchen faucet until hot before starting the dishwasher to ensure hot water reaches it immediately.

Spray arm clogs are extremely common. Remove the spray arms and clear any debris from the small holes. In Arizona's hard water areas, mineral deposits frequently block these openings.

Detergent matters more than many people realize. Using too much, too little, or the wrong type affects cleaning performance. Premium dishwashers like Miele and Bosch often work best with specific detergent formulations.

Loading technique impacts cleaning effectiveness. Overloading prevents water and detergent from reaching all surfaces. Follow the manufacturer's loading guidelines for optimal results.

The wash impeller (in applicable models) circulates water throughout the dishwasher. A worn or damaged impeller reduces water pressure and cleaning power.

Check that the detergent dispenser opens properly during the wash cycle. A faulty dispenser latch leaves dishes cleaning with only the prewash amount of detergent.

Water inlet valve problems can reduce water pressure inside the dishwasher. Listen for the dishwasher filling at the beginning of the cycle. Slow filling indicates a possible valve issue.

For spotty dishes specifically, the rinse aid dispenser may be empty or malfunctioning. In hard water areas like Gilbert and Chandler, rinse aid is essential for spot-free results.