A dishwasher features an electro-mechanical control mechanism, a water intake valve, an electrically powered water pump, and a direct-drive motor. These dishwasher parts function together to clean and rinse dirty dishes and eating utensils in either hot or cold water. Many dishwashers also have a heating element, detergent dispenser, racks, and both upper and lower spray arms.
The control mechanism is a control panel which users operate to start or adjust a cycle. Traditional dishwashers used an electro-mechanical system with a turning knob. These were eventually upgraded to computerized control mechanisms that allow users to adjust the cycle time, spray intensity, and draining functions. Due to its complexity, if a control panel goes bad the only way to repair it is to buy a spare one and have it professionally installed.
Both the intake valve and the pump function to supply the dishwasher with water, and then later direct that water into a drainage hose. An electric motor drives the pump, and it can be reversible. A reversible pump is able to supply water to the spray arms while simultaneously draining water out of the pump. Repairing a dishwasher pump or intake valve can be done manually, but it requires carefully disassembling the parts and locating the problem area.
The most important dishwasher part is the motor. It powers the pump and is driven entirely by electrical energy. Since the motor is an extremely complex electrical device, it shouldn’t be tampered with by non-professionals. A repairman should be called if the motor stops running because some of the parts have worn down and become faulty.
Most dishwashers also include a heating element to dry dishes, a detergent dispenser to more evenly distribute soap, and upper and lower spray arms. The spray arms feature holes from which water jets upward or downward at a high velocity. Dishwashers originally only featured bottom-placed spray arms, but more premium models were eventually released. These offer both upper and lower sprays so that dishes can be better cleaned.
The most expensive models include premium dishwasher parts, such as child safety locks for added safety, a door latch to prevent water leakage, and sound-absorbing panels that reduce the dishwasher’s total noise output. Since many of these dishwasher parts aren't needed for basic dish-washing, they aren't typically included in a standard home unit. Instead, the homeowner is given the option to upgrade if so desired.