A ceramic mixer tap cartridge is a cylindrical component located at the centre of the tap and is responsible for regulating water flow and temperature. It consists of a pair of discs that sit atop one another – the bottom disc remains fixed while the upper disc rotates when the handle is operated.
Ceramic Disc Cartridges will Last a lifetime. But it depends on the hardness of your water, and the quality of the tap itself. A cheap tap, even with ceramic discs, will wear down over time.
Mixer tap cartridges fail by leaking. Mixer tap cartridges use ceramic discs to control the water flow and these can sometimes get full of limescale and dirt which can cause them to leak. When this happens you will need to replace the mixer tap cartridge.
The two mainsizes for cartridges are 35mm and 40mm, which relates to the size of the cartridge.