Hi Oliver, first of all you ...

Hi Oliver,

first of all you have to remove the scale from your cooling system than you have to clean up with a disinfection with bio dispersant and chlorine (the cheapest way).

the first step: Depend on how much is havy the problem, but normally I suggest to use sulphamic or formic acid (with corrosion inhibitor), you could use a blending ready to use (2-5% of concentration should be enough)....keep the system under treatment controlling the pH value ...

second step: you must use chloride (keep 1 ppm of free chlorine inside the system for 5-8 hours) with 50 ppm of bio dispersant ( if you don't use it, you won't be able to remove biofilm) ....than you have to discharge the cleaning solution 

I can send you the procedure ...write me on m.testoni@ncr-biochemical.it