In our NHT unit of isomerization plant we are frequently facing issues of reactor effluent air fin coolers tube leak. It has happened twice in 6 months and this time around afc inlet line developed leak as well. Feed composition total Sulphur is 140ppm and chloride is 2ppm. Our wash water injection is continuous and injection rate has been increased to twice the design flow as recommended by licensor. In recent shutdown salt deposit was also observed before water injection point in last 2 effluent exchangers. Boot sample result is having pH :5.7, cl : 70ppm & iron content : 50 ppm. Our unit is designed for handling 17ppm chloride impurities in feed but still the corrosion rate is higher. Please suggest any solutions.