Many HVAC manufacturers, distributors and contractors may not
realize that hundreds of thousands of coil failures have
occurred during the last decade from corrosion. The cause is
most typically environmental pollutants, which range anywhere
from salt-air, to household cleaning agents, pesticides,
formaldehydes, building materials, and even off-gassing of food.
Each of these contaminant sources can initiate corrosion in coil
tubing in a year or less when the conditions are right. For
example, refrigeration coils were continually failing in a South
American fruit processing plant’s banana room that used fruit-
ripening ethylene gas generators. Gaseous by-products from the
catalytic generator combined with the moisture in the ripening
area formed a weak acid that resulted in pinhole leaks in the
coil tubing after a year or less. Aside from fruit processing
plants, most coastal area HVAC equipment – whether it’s
commercial or residential – is also bombarded with corrosion
from ocean salt. Two Common Types of Coil