Nu-Calgon Nickel-Safe Ice Machine Cleaner. Nu-Calgon nickel-safe ice machine cleaner (part number WX08X42870) is a food-grade solution that works for under counter ice makers with lead and nickel plated evaporators.Follow the instructions on the label when using Nu-Calgon nickel-safe ice machine cleaner WX08X42870.Not for use on models UNC15NJII or UNN15NJII.- Nu-Calgon Nickel-Safe Ice Machine Cleaner.