1. Remove the 4 screws underneath the doser (use a T10 Torx screwdriver) and carefully lift the top cover; watch out for the wires which are connected to the LED indicator and mainboard

2. Carefully disconnect the wires connected to the mainboard from the pump motors and ribbon cable

3. Lift the whole front face with the pump heads and remove the 4 screws which hold the pumps in-place; use the same T10 screwdriver

4. Rotate the heads, put the screws back on, connect the ribbon cable and re-install front face plate

5. Reconnect the remaining cables to the mainboard, put the cover back on with the screws.