Proper Operation
Learn how your appliance is supposed to operate so you can determine if it is malfunctioning.


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Filling

Two-Coil Inlet Water Mixing Valve

The washer tub is filled with water prior to the wash and rinse functions. If the cycle control is rotated to the wash function at the start of a cycle and pulled out, the wash function cannot begin until the tub has filled. The fill function is implemented by configuring the water level switch, the water temperature switch and the water inlet valves in a sequential string. As long as there is not enough water in the tub to satisfy the water level switch, the control voltage is presented to the water temperature switch. The water temperature switch selects the combination necessary to satisfy the wash temperature selection; hot only, cold only or both hot and cold. The control voltage is passed on to the solenoid coils of the water inlet mixing valves to allow the water to flow through the inlet water hoses and into the tub.

Fill Control Diagram

There is a solenoid coil and a water valve for both the hot and cold water. This two-solenoid mixing valve has a body made of nylon with the two solenoid coils and valves mounted on it. The mixing valve body has two standard threaded hose fittings to accept the water inlet hoses. Metal filter screens are located in both inlets to prevent dirt, sand and other foreign particles from jamming the valve seats. The valve contains a rubber diaphragm with a tiny hole in the center. A metal spring-loaded stem (armature) with a cone-shaped tip fits into the crater and hole in the middle of the diaphragm. The spring keeps the tip seated in the hole at the center of the diaphragm and prevents the passage of water through the valve. When the solenoid coil is energized, the coil becomes an electromagnet which pulls the metal stem up into the coil (the stem is inside a water-tight guide) and allows water to flow through the valve.

As the water fills the tub, some of it flows into the water level switch air dome and compresses the air there (See Water Level Control Switch). When the selected water level has been satisfied, the air pressure will have deflected the diaphragm in the water level control enough to switch from "fill" to "wash".

The tub is also filled during the rinse cycle to help remove the wash detergent. The water temperature is determined by the temperature selection for rinse. Most washers also spray water in during the spin function of a rinse sequence.