Accessing the cartridge
1 - Using a flat-head screwdriver, remove the plastic cover, then remove the screw with a 3 mm Allen key.
2 - Dismantle the lever by pulling upwards, then remove the cap.
3 - Unscrew the nut with a large, 32 mm socket wrench and pull the cartridge firmly towards yourself. If necessary, replace the lever to make this easier.
4 - Make sure there are no seals or foreign objects in the mixer body.
5 - Then install the new cartridge into the mixer body, positioning the two tabs on the cartridge into place.
6 - Screw the large nut back with moderate pressure using the 32 mm socket wrench. Replace the cap.
7 - Replace the lever and tighten the screw with the hex key.Finally refit the plastic cover.