Replacing the filter in a Whirlpool refrigerator involves locating the filter (typically in the front or bottom grille), shutting off the water supply, unscrewing the old filter, and installing the new one using a filter wrench or pliers. Most Whirlpool models use carbon or activated carbon filters to remove contaminants from drinking water and ice. The filter should be replaced every 6 months to ensure optimal performance in removing impurities and preserving water quality. Filter maintenance includes resetting the indicator light, cleaning the housing, and troubleshooting water leaks or reduced water flow.