Dear Tamer, you are not ...
Published by Jitendra Kumar
Dear Tamer, you are not specified MOC of heat exchanger and applicable Temp.
you can use NaOH as scale softener before Descaling with 10% solution for 4-6 hrs as volume of system then use Sulfamic acid with 10% solution maintain pH 2-3 for cleaning till max. 4-6hr.