Given you have a multi-group commercial espresso machine, the descaling process could be anywhere from "preventative maintenance" with mild citric acid solution to a full teardown with acid soaks. It can get rather ugly:



You could fumble your way through by piecing together advice from searching on how to descale a commercial espresso machine. It's not rocket science for the modestly handy, but it's not a beginner project either. I recommend contacting a local espresso repair technician.