Could I have prevented my HVAC unit from corroding?
Coil corrosion is an expensive problem in the HVAC industry, leading to coil replacement or entire system replacement. Corrosion results in failure, and is responsible for about 40% of equipment failures in industrial applications, according to CED Engineering
As the authors of an article in Reliable Plant explain, coil corrosion comes in the form of either pitting or formicary deterioration. Corrosion may occur as quickly as a few weeks after an installation or it may take up to four years to present itself.
Pitting corrosion is most often caused by exposure to fluoride or chloride. Fluoride is present in municipal water supplies, while chloride is found in a variety of products including snow melt, detergents, cleaners, carpeting and fabrics. Pitting occurs when chloride or fluoride ions are transported to the metal via condensate. The ions attack the metal, forming pits that form pinholes, causing the coils to leak refrigerant.