Once you've removed the kitchen tap ireland cartridge, you can clean and replace the cartridge and replace the screw and handle with a new one. To do this, you'll need an Allen wrench and pliers. If the screw is stubborn, you'll need a special tool to get it off. You'll need to remove the decorative cap and remove the handle screw before you can get to the cartridge. After the cartridge has been replaced, make sure to clean the nut and the handle connector.