According to a recent survey, 73% of U.S. households have a dishwasher, even though another survey reveals this convenient appliance often goes unused by 20% of those who own one. Okay, so perhaps one in five of us prefer to wash and dry dishes by hand. But is there comfort in knowing that the dishwasher is standing by, ready to do the dishes for those times when we have better things to do? If your malfunctioning dishwasher forces us to clean the dishes ourselves, does it make the chore that much more unpleasant? Let's agree it's better to have a choice and obtain that dishwasher back in good working order. Before you can diagnose why a dishwasher stops working properly, you need to know how it works.
How a dishwasher works
When you select a wash cycle in your dishwasher, the control sends 120 volts of alternating electric current to the water inlet valve solenoid which opens the valve and permits the proper amount of water into the tub. This process will take between 90 seconds to two minutes and will usually allow around two gallons of water to fill the tub.
Once the fill cycle has completed, the control sends voltage towards the circulation pump motor which uses an impeller to force water through the dishwasher's wash arms. As the food debris is cleaned in the dishware, it collects in the sump which filters and retains the larger food particles, preventing the particles from circulating in to the wash arms and, potentially, clogging them. Because the water circulates through the arms, a wax motor or solenoid causes the dispenser to open and release detergent to mix with the water. Depending on the setting, the control may send voltage to a heating element periodically during the wash cycle to keep a water temperature between 120-degrees and 160-degrees Fahrenheit.
After the completion of each wash cycle, the control sends voltage towards the drain pump that uses an impeller to force the water through a drain hose to some garbage disposer or standpipe. The dishwasher will then go through several rinse cycles which are similar to the wash cycles and may introduce rinse aid to water to help with drying and also to reduce streaking if your home uses calcium in the water. Following the rinse cycles, there is a final drain cycle, even though some water will be left in the tub to help preserve the seals and stop cracking. Finally, the drying cycle begins. Some models use a heating element to heat the air inside the tub while other models will depend on the heat generated by the final rinse cycle. The hot moist air will exit through a permanent vent or through a vent in the door which is opened with a wax motor or solenoid. With the drying cycle completed, the dishware is ready to be removed from the dishracks.
Top 5 reasons your dishwasher is not cleaning
So, what causes a dishwasher to prevent cleaning? Here are the top five reasons:
- Defective Water Inlet Valve – A clogged or defective water inlet valve won't allow enough water in to the tub to clean the dishware properly. To assist determine this, pour one to two quarts of water into the bottom of the tub and run the dishwasher. When the wash performance improves, the valve is most likely restricted and should be replaced. Attempting to clean out an old valve isn't recommended since the damage brought on by the initial restriction puts the part in a greater risk for failure in the future.
- Clogged Wash Arm – With time, food particles can clog the small holes in the wash arm, obstructing the water flow. You should use a small brush or pipe cleaner to clean out the debris as part of your regular dishwasher maintenance.
- Damaged Wash Arm Support – On most dishwasher models, the water reaches the wash arms via a support tube. A damaged support may be unable to mate properly with the supply tube nozzle, obstructing water. For some models, the support could be replaced separately from the arm, but you may need to purchase an entire wash arm assembly to fix the problem.
- Broken Impeller – A broken circulation pump impeller might not be able to generate enough pressure to drive the water. Depending on the model, you may be able to replace the impeller independently of the circulation pump motor.
- Faulty Circulation Pump Motor – When the circulation pump motor doesn't make any noise during operation, or just hums after the tub has been filled with water, then the component has probably burned out. You will need to replace the pump motor with a new one before your dishwasher will be able to start cleaning again.
Find the right dishwasher parts with Repair Clinic
Repair Clinic stocks all of the replacement parts you need to repair or keep your dishwasher, including drain hoses, water inlet valves, drain pumps, circulation pump motors, wash arms, dishracks, heating elements, plus much more. To get started, you'll need to identify the dishwasher's model no . which can be found on a label attached to the top or side from the dishwasher door. Enter the full model number of the appliance in the Repair Clinic website search bar for an entire list of compatible parts. Repair Clinic carries parts for all the top brand dishwashers including Bosch, KitchenAid, Kenmore, Maytag, Samsung, GE, Frigidaire, LG, and Whirlpool, but you'll need to make sure you're purchasing the right part for this to work with your model.
