How do I clean my Hach CL-17 chlorine analyser

Hach CL17 Chlorine analysers are in use 24 hours a day, providing vital data about drinking water quality. The coloured reagent can deposit in the cell and affect the performance of the analyser in the long term and give high readings.
A recommneded solution is to clean the cell with sulphuric acid in a dropper bottle, which cleans and de-colours the cell to ensure quality results. This is available from Camlab Part code HH/02038-32 1132348