To change a water filter cartridge: Turn off the water supply to the filter system. Release any pressure in the system by opening a faucet. Remove the housing or cartridge holder containing the old filter cartridge. Dispose of the old filter cartridge properly. Insert the new filter cartridge into the housing, following the manufacturer's instructions. Reattach the housing or cartridge holder securely. Turn on the water supply and flush the system according to the manufacturer's instructions. Check for any leaks and tighten connections if necessary. Reset the filter change indicator, if applicable. Your water filter cartridge has been successfully changed.