Refrigerant piping can be protected from corrosion through the use of corrosion-resistant materials, such as copper or stainless steel, and applying a corrosion-inhibiting coating to the piping and fittings. Additionally, ensuring proper drainage and drying of the piping system, as well as minimizing moisture exposure, can help prevent corrosion. Regular cleaning and inspection of the piping system can also help identify and address corrosion issues before they become major problems.