The automatic dishwasher operates by forcing a high-velocity stream of hot water, mixed with a detergent solution, against dirty dishes. This jet action combined with the high water temperature provides a cleaning action that both scrubs the dishes and eliminates bacteria. The dishwasher then drains the dirty water away, rinses the dishes with fresh hot water, and dries the dishes with hot air.
Like most automatic appliances, the dishwasher is controlled by a timer. The timer is a clock-
Actuated switch which actually contains a number of switching contacts that can energize different cycles. The clock motor begins to run as soon as you start the machine, and it continues to run until the end of the wash cycle. At that point, a contact opens and breaks the circuit to the timer motor.
Some dishwasher functions are controlled by small electromagnetic devices called solenoids. Solenoids are coils of wire that concentrate the magnetic force surrounding any wire which has current flowing through it- When energized by the timer, a solenoid attracts a pole or armature; this movement in turn, carries out some mechanical work. In the dishwasher, for example, a solenoid located in a water valve allows water to flow into the machine; the solenoid opens the valve in much the same way that you would open a faucet. When the timer contacts to the solenoid circuit open, current ceases to flow, and the solenoid then shuts the water off.
In most dishwashers, the precise volume of water necessary for efficient operation is controlled by a small regulator in the water valve known as a flow washer. This regulator reduces flow within the line to approximately 20 pounds per square inch,

Much lower than the pressure found in most c-7* water mains. Since the flow washer- controls water pressure and the timer controls the length time that the water inlet is open, dishwasher can engineer machines that utilize a spec quantity of water every time they are operated.

Dishwashers use only hot water. Ideally, water temperature should be between 140 and 160 degrees for proper cleaning of your dishes. If the temperature is less than 140 degrees, the dishwashing detergent cannot dissolve properly and certain greases cannot emulsify entirely. The result of course, is poor cleaning performance. Consequently, the water temperature is one of the firs: things that you should check if your dishwasher ever fails to clean properly. You can use a candy or a meat thermometer in the dishwasher to measure the water temperature.

Always measure the water temperature during the second wash cycle. If the water temperature in your dishwasher is too low, then raise the thermostat setting on your water heater. The dish, washer heating element cannot compensate for are insufficiently heated water supply; the element's main responsibility is to maintain the water temperature during normal wash periods. If there were n-- heating element, the spraying action of the way-=-- against the cool sides of the cabinet could lower the water temperature substantially during the course of a single wash period.

Most dishwashers have detergent dispensers that permit the cleaning agent to enter the water at the proper time. Since there are usually two wash cycles, each must have its own charge o- detergent. Therefore, one side of the filled dispense-is usually open, while the other is latched shut. When- the dishwashing cycle begins, the hot water flushes the detergent from the open container; after the second wash cycle begins, a solenoid (or bimetal stir unlatches the second compartment, allowing the second charge of detergent to be discharged into the water.

After its wash cycle, the dishwasher goes through several rinse periods to remove any remaining detergent or food particles. In addition, some dishwashers provide two other actions during the final rinse period: one is a sanitizing treatment, and the other reduces spotting.

The sanitizing feature utilizes an electric heating element to raise the water temperature to at least 150 degrees to reduce the bacteria count. The sanitizing cycle turns the timer motor off and allows the heating element to remain on until a bimetal thermostat which senses the water temperature — closes, turning the timer motor on again. Since it takes about one minute to raise the dishwasher's water temperature one degree, it could take around 30 minutes to heat the water temperature up to the level required by the sanitizing cycle, if your home's hot water temperature is low (around 120 degrees, for instance). This is another good reason to be sure back into position and press the start switch. The ram will travel upward, at which point you can open the container drawer and rearrange the trash. Then, you can start the entire cycle all over again