There are three common styles of ice maker; modular, flex-tray and component (aka compact). The flex-tray uses a twisting force to free the ice from the flexible tray. This style of ice maker is not found as often anymore and is not covered specifically in this site, although some of our articles are relevant to this style. The other two styles use a metal ice mold with an electric heater to loosen the ice and both are substantially similar in operation.
Water travels from a tap, usually under the kitchen sink or behind the refrigerator, to the back of the fridge. Water lines are commonly copper or plastic tubing. The water line connects to the water inlet valve, which controls the flow of water. When the inlet valve receives electrical current from the ice maker, the solenoid on the valve is triggered and allows water to flow. Water travels through the outbound water line into the freezer and into the ice mold.
The cycling of most ice makers is initiated by a thermostat attached to the ice mold. It monitors the temperature of the mold and when it drops to a preset temperature, the thermostat signals the ice maker to begin an ice making cycle.
The motor turns the ejector blades which rotate until they contact the ice. Because the ice is frozen to the mold, it cannot be pushed out and the motor stalls. As the blades continue to press on the ice, the ice mold heater begins heating the mold. Once the ice loosens the ejector motor turns, the mold heater shuts off and the ice is pushed out.