The Water Inlet Valve Washer is an OEM part for Whirlpool refrigerators. It seals the connection between the water inlet valve and the water supply line, preventing leaks and ensuring a secure connection for the water flow into the refrigerator. You should replace this water inlet valve washer if it becomes worn out or damaged. Causes of a bad washer can include prolonged exposure to water, mineral buildup, or general wear and tear. A faulty washer can lead to water leaks, reduced water pressure, or issues with the ice maker and water dispenser.